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University of Montana ScholarWorks at University of Montana Theses, Dissertations, Professional Papers Graduate School 1984 Electromagnetic characteristics of the Staggered Spondaic Word Test Holli J. Bell The University of Montana Follow this and additional works at: http://scholarworks.umt.edu/etd Recommended Citation Bell, Holli J., "Electromagnetic characteristics of the Staggered Spondaic Word Test" (1984). Theses, Dissertations, Professional Papers. Paper 2204. This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Theses, Dissertations, Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. COPYRIGHT ACT OF 1976 THIS IS AN UNPUBLISHED MANUSCRIPT IN WHICH COPYRIGHT SUB SISTS. ANY FURTHER REPRINTING OF ITS CONTENTS MUST BE APPROVED BY THE AUTHOR. MANSFIELD LIBRARY UNIVERSITY^OE IJQNJANA DATE ELECTROMAGNETIC CHARACTERISTICS OF THE STAGGERED SPONDAIC WORD TEST by Holli J. Bell B.A., Communication Sciences and Disorders University of Montana, 1981 A thesis submitted in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Communication Sciences and Disorders in the Graduate School of the University of Montana November, 1984 Approved by: , - desn, Graduate Sdnool UMI Number: EP34660 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent on the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMT Dimw^dlkm MMhg UMI EP34660 Copyright 2012 by ProQuest LLC. All rights reserved. This edition of the work is protected against unauthorized copying under Title 17, United States Code. ProQuesf ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 -1346 ELECTROMAGNETIC CHARACTERISTICS OF THE STAGGERED SPONDAIC WORD TEST by Holli J. Bell B.A., Communication Sciences and Disorders University of Montana, 1981 An Abstract Of a thesis submitted in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Communication Sciences and Disorders in the Graduate School of the University of Montana November, 1984 Thesis Director: Charles D. Parker, Ph.D. ABSTRACT Bell, Holli J., M.A., November, 1984 Communication Disorders Electromagnetic characteristics of Test (81 pp.) Director: the Staggered Sciences and Spondaic Word Charles D. Parker, Ph.D. Thesis approved; The Staggered Spondaic Word (SSW) test, which is comprised of pairs of spondees recorded in a partially dichotic manner, was developed for the purpose of assessing the integrity of the central auditory system. Various response patterns have been outlined and are considered to be indicative of sites or general areas of dysfunction. Scores and response patterns are used in making diagnoses as well as in intervention planning in various populations. Upon analyses of 10 reel-to-reel recordings of the SSW, discrepancies as large as 10.5 dB among recording levels of syllables were found. Not only is it impossible to accurately predict the effects of recording level differences on various populations, but the random nature of the differences makes prediction of individual performance on more than one recording impossible, as well. ii TABLE OF CONTENTS page LIST OF TABLES v LIST OF FIGURES vi INTRODUCTION 1 METHOD Test Materials Apparatus and Calibration Procedure 6 5 6 7 RESULTS Recording Levels of Syllables Channel Effects Measurement Reliability and Validity Harmonic Distortion 16 17 27 28 28 DISCUSSION 34 CONCLUSION 41 REFERENCES 42 APPENDIX A: Central Auditory Function: The Process and Tests Designed to Evaluate It 49 APPENDIX B: The Staggered Spondaic Word Test Scoring Interpretation 53 57 58 APPENDIX C: The Association Between Learning Disabilities and Central Auditory Processing Disorders 62 APPENDIX D1: List C-EC 69 APPENDIX D2: List EC 70 APPENDIX D3: List EE 71 iii TABLE OF CONTENTS (continued) APPENDIX E: Playback Calibration of the Akai Tape Recorder Head Alignment Tape Speed Frequency Response 72 72 72 72 APPENDIX F1: 75 Syllable Ranges per Item — List EC APPENDIX F2: Syllable Ranges per Item — List C-EC .... 77 APPENDIX F3: Syllable Ranges per Item — List EE 78 APPENDIX G: Instrument Settings 80 iv LIST OF TABLES Table 1 page Description of Tape Sample 9 2 Differences between Conditions — Tape #1 18 3 Differences between Conditions — Tape #4 19 4 Differences between Conditions — Tape #7 20 5 Differences between Conditions — Tape #8 21 6 Differences between Conditions — Tape #10 22 7 F Values for Scheffe Test for Right-Competing Condition Between Tape Differences 23 8 F Values for Scheffe Test for Left-Competing Condition Between Tape Differences 24 9 F Values for Scheffe Test for Right-MonCompeting Condition Between Tape Differences 25 F Values for Scheffe Test for Left-NonCompeting Condition Between Tape Differences 26 Recording-Level Ranges of Individual Test Items for Each Condition by List 29 12 Inter-Channel Differences for Competing Syllables ... 30 13 Differences Between Syllable Recording Levels for Conditions by Tape 31 14 Harmonic Distortion 33 B1 SSW Scoring Symbols 59 CI Auditory Abilities Important to the Learning Process 67 El Frequency Response of Akai Recorder Upon Initial Optimalization 73 10 11 E2 Frequency Response Upon Final Characterization of Akai Tape Recorder V 74 LIST OF FIGURES Figure 1 page Recording Level Measurements; Equipment Arrangement 2 Harmonic Distortion Measurements: Arrangement 3 B1 10 Equipment 12 Example of a Tracing 14 Example of Two Test Items 56 B2 SSW-Gram 61 vi Page 1 INTRODUCTION The Staggered Spondaic Mord test (SSW) was developed by in the early I960's to difficult speech central auditory material in order processing to bypass peripheral auditory mechanism and heavily stress the CANS (Katz, (An explanation of this function, due primarily existing especially those 1963). tests with of to the prevalent use of monosyllabic words. Performance on monosyllabic word tests by listeners with CANS, the phenomenon may be found in Appendix A.) Katz (1962) cited lack of specificity and reliability in central Katz assess the integrity of the central auditory nervous system (CANS). Existing tests of (CAP) utilized Jack peripheral impairment, indistinguishable from the performance of those with central intact may be pathology (Speaks & Jerger, 1965). The prevented lack the populations. to so, reliability inherent in monosyllabic word introduced which tests establishment of normative data for particular tests and Examiners were forced to carry out lengthy test compensate fatigue of batteries for reliability and specificity weaknesses, but in doing the could possibility conceivably of psychological and physiological cause deleterious effects on patient Page 2 performance (Katz, 1962). Katz developed the SSW to provide a more valid and reliable measurement tool to evaluate the integrity of the CANS without artifact, even in the presence of peripheral impairment (Katz, 1962). He employed spondees, "...those (words) composed of two monosyllabic words which are spoken with equal stress" (Katz, Basil & Smith, 1963) as test items. (A description of the SSW may be found in Appendix B.) In support of his choice of stimuli, Katz cited the work of Calearo and and Bocca (1961) who demonstrated a tendency Lazzaroni (1957) for improved test reliability when utilizing Italian trisyllabic words and short sentences in a group of normal-hearing individuals with a broad range of abilities on tests of intelligence, vocabulary and memory. three variables (1963) stressed thresholds for did not that English affect the test reliable spondees They found that scores. these Katz, Basil and Smith relationship between reception and thresholds for pure-tones in the speech frequencies, for hearing-impaired and normal-hearing individuals further supports the use of spondees. Since its inception, over 20 years widely-used diagnostic tool. In ago, 1972, the Auditec SSW has foreign them throughout countries (Carver, the United 1983). In a a of St. Louis began reproducing the SSW at a rate of approximately 175 tapes distributing become States as per year and well as several questionnaire survey of audiometric practice, Martin & Forbis (1978) found that in 1977, the SSW was one of the three most frequently used tests for the diagnosis of central auditory disorders among the audiologists surveyed in the United Page 3 States. Upon examination of the literature one finds that the SSW has used clinically and experimentally to assess central auditory function in various populations including learning Enfield & Sherman, 1981; disabled children (Johnson, Dempsey, 1977) (see Appendix C), stutterers (Hall & Jerger, 1978), a vasculitis patient (Musiek & patients with been temporal lobe Morgan, 1981), lesions (Balas, 1971; Jerger & Jerger, 1975), patients with cortical lesions and temporal lobe seizures (Balas, 1971), 1980; children with auditory processing problems (Musiek & Geurkink, Dempsey, 1977), autistic children and adults (Wetherby, Koegel & Mendel, 1981), children with previous middle ear effusion (Hoffman-Lawless, Keith & Cotton, 1981), chronic alcoholics (Spitzer Ventry, 1979; Welsh& 180), patients & with corpus callosum lesions (Musiek & Wilson, Katz, Avellanosa & Aguilar-Markulis, 1980), dyslexies (Welsh, Healy, 1980), normal adult listeners (Arnst, 1981), older adults (Amerman & Parnell, patients with 1980), adolescents (Otto & Johnson, penetrating head 1983) and injury (Mueller, Sedge and Salazar, 1983). Several investigators have been concerned with the of competing syllables on the SSW (Rudmin & Katz, 1982; Mathies & Garstecki, 1980; Beasley, onset-alignment Katz, Habner & Lohnes, 1977; Rudmin, 1981; and Freeman 1976). They have employed oscilloscopic studies using as many as six different reference points from which to measure the onset single & monosyllable, as of a well as an "auditory-manual" method (Rudmin & Katz, 1982) in which the tape was marked (by hand) at the point where Page 4 the listener judged the onset to occur. Upon reviewing these studies, the most significant feature which emerges is results. Considerable debate among these inconsistencies has ensued. results include procedural the inconsistency investigators over the cause of Explanations offered error among for discrepant and inaccurate data reporting. example, Katz and Rudmin (1982) compared their oscilloscopic tracing the competing syllables "shore" (1976) tracing of the same. and "out" of to Freeman and Beasley's Katz and Rudmin found that "shore" preceded "out", while Freeman and Beasley obtained the opposite result. Rudmin concluded from their comparison that Freeman and reversed For Katz and Beasley simply all positive and negative signs when reporting their data. It is unclear, however, how they arrived at this conclusion. In addition to onset-alignment discrepancies, inconsistencies exist among normative data generated 1983; Mueller, Sedge & and Schultz, Freed, Fournier by different authors (Otto & Johnson, Salazar, 1983; & Hughes, 1984). and Berrick, Shubow, It has been suggested that the use of different forms or lists of the SSW could account for these differences. Another possible explanation which which could account for both has not been addressed, but onset-alignment differences as well as inconsistencies among normative data is differences characteristics among individual tapes. Shea and Baffin (1983) analyzed the recording characteristics of tapes Auditory Processing Test intra-tape, but inter-tape Battery. in the recording of Willeford's (1976) Central They were interested not only in reliability, as well. They found large Page 5 discrepancies in the recording levels between tapes, tests and channels and concluded that use of the Willeford Test measurement tool is Battery as a diagnostic inappropriate until standard recordings and norms are developed. The purpose of this recording levels of study test is to determine items, within when a sample of recordings distortion levels items on the tapes calibration tone); are are tone. insignificant (re: recorded in a of harmonic distortion are generated through a clinic audiometer at levels above the calibration that reliability and among recordings of the Staggered Spondaic Word test and measure levels of present the like The hypotheses are N.A.B.) and that all manner (re: reference and if not, that deviance from the calibration tone is uniform across tapes in both magnitude and direction. Page 6 METHOD Test Materials. totalling 10, clinics in the Recordings were of obtained United the from States. Staggered Auditec (see Table Spondaic Word test, of St. Louis and various 1 for a more complete description of the tapes used.) Apparatus and four-track with Calibration. tape For intensity promulgated Broadcasters (NAB) Standard by Magnetic the National Tape (1965), was used as the playback instrument for E measurements, a recorder (Akai, model 1722), calibrated in accordance specifications Appendix level Association of Recording and Reproducing the recordings. (see for a description of equipment calibration procedures.) The output of the tape recorder was fed to a microphone amplifier Kjaer, Type 2112). (Bruel & Output of the microphone amplifier was connected to the input of a continuously recording graphic-level recorder (Bruel & Kjaer, Type 2305). For distortion four-track tape level recorder measurements, a Sony (model TC-377), calibrated in accordance with specifications set forth by the NAB Standard Tape Recording and Reproducing (1965), was used as the playback instrument. The output of the taperecorder was fed Page 7 to a Grason Stadler audiometer (model GSI-10), calibrated in a manner compliant with requirements specified by the American National Standards Institute (ANSI-S3.5-1978), via the left earphone (Telephonies TDH-50P, held in a Telephonies MX 41 AR cushion). The earphone was coupled to a sound level meter (Bruel & Kjaer, Type 2603) via coupler. (Figures 1 and 2 provide block a 2-cubic-centimeter diagrams arrangements). Tape recorder heads were cleaned and begining of each of equipment degaussed at the measurement session and each track was then recorded graphically (see Figure 3). Procedure. Prior to intensity level measurements, both channels of tape recorder the were set to a convenient reference point relative to the 1000-Hertz (Hz) calibration tone present at the beginning of both tracks of each tape. The calibration tone from each track was then recorded graphically (see Figure 3)levels of Following the calibration intensity each monosyllable were also recorded (graphically) and their maximum root-mean-square (RMS) values were measured respective tone, calibration session, one of the tone tapes tracings. was At re-analyzed the to with reference to end of a measurement determine measurement reliability. Levels of harmonics of harmonic the distortion so determined by summing the 1000-Hz calibration tone on one channel of each tape when played at 70 dB HL, with the adjusted were audiometer volume unit (VU) meter that the SLM reading reflected the energy generated by the calibration tone plus 10 dB. This level was chosen as it is one of the Page 8 highest recording levels (re: the reference calibration tone). The output level of 70. dB (HL) was chosen arbitrarily and would simulate the presentation of the test to a patient with speech thresholds of 20 dB (HL) as the test is to be presented at 50 dB (SL). Page 9 Table 1 Description of Tape Sample A = Tape purchased directly from Auditec 0 = Tape dubbed by amateur List A 1 EC X 2 EC 3 EE 4 D Age Use 1 ÏR. Research Only 5 YRS. Clinical & Research X 1 YR. Research Only C-EC X 1 YR. Research Only 5 EC X 2 Mos. Research Only 6 C-EC X 2 Mos. Research Only 7 EE X 2 Mos. Research Only 8 EC X 8--10 Yrs. Clinical & Research 9 EC X 5-•6 Yrs. Clinical & Research 10 EC 5--6 Yrs. Clinical & Research X X Page 10 Figure 1 Recording Level Measurements: Equipment Arrangement Tape Recorder (Akai) Microphone Amplifier Graphic Level Recorder Figure 1 Page 12 Figure 2 Harmonic Distortion Measurements: Equipment Arrangement Tape Recorder (Sony) Audiometer Sound level PhOr : Coupler Meter I Figure 2 Figure 3 Example of a Tracing Bruel & Kjaar Tbr "1 rx i -rfSi-tï=t i—h iti < I il'H -U• I \ "!| ' ^ 'II * vvT 1 44^ -i !'-TT'• n TTi tt HM Calibration i'u!: ' Tone OP 1102 Figure 3 -1 nr 1,1*! v;'t tt±i m: Carrier Phrase "Are you ready?" m -TT-t- S m Practice Item "North-West" Page 16 Results In nearly all cases, Deviance from direction; the monosyllables calibration however, the were not recorded at 0-VU. tone was nearly always in the positive magnitude of the discrepancies varied at random. Analyses of variance (ANOVA) performed on intensity levels revealed a significant difference 1430; f= 12.691; among separate among monosyllables on the 10 tapes (df= 9, p < 0.001) Significant differences listening conditions - (RC), Left-noncompeting p < 0.001) such recording levels vary as a function of listening condition and the degree to which they fluctuate varies as a function tape found A two-way ANOVA revealed an interaction between tape and listening condition (df= 27,1400; f= 3-369; that also Right-competing Left-competing (LC), Right-noncompeting (RNC) and (LNC) - within 5 tapes. were being examined. Scheffe follow-up determine the source of the interactions. tests of were the particular undertaken to The results are summarized in Tables 2 - 10. Significant inter-channel differences were noted on tape numbers 8 and 10 (see Tables 5 & 6). Page 17 Recording Levels of Syllables. The highest intensity level (re: calibration tone) of an individual syllable across the 10 tapes is 10.0 dB and lowest the is -0.5 dB. individual syllable levels for tapes The overall 1 through intensity 10 are: ranges of 8.5, 6.5, 9.5, 6.5, 8.5, 5.0, 9.5, 7.5, 6.5 and 9.5 respectively (see Appendix F). Page 18 Table 2 F Values for Scheffe Test for Differences Between Conditions Tape LeftCompeting (LC) RightCompeting (RC) LeftCompeting RightNoncompeting 0.850 1** RightNoncompeting (RNC) LeftNoncorapeting (LNC) 0.238 0.688 1.088* 0.163 0.925 *significant at the .05 level of confidence **purchased from Auditec and used for research only played less than 6 times Page 19 Table 3 F Values for Scheffe Test for Differences Between Conditions Tape LeftCompeting (LC) RightCompeting (RC) LeftCompeting RightMoncompeting 1.000* 4** RightNoncorapeting (RNC) LeftMoncompeting (LNC) 0.225 0.975 0.775 0.025 0.750 *signifleant at the .05 level of confidence **purchased from Auditec and used for research only played less that 6 times Page 20 Table 4 F Values for Scheffe Test for Differences Between Conditions Tape LeftCompeting (LC) RightCompeting (RC) LeftCompeting RightNoncompeting 1.050* 7** RightNoncorapeting (RNC) LeftNoncompeting (LNC) 0.375 1.063* 0.675 0.013 0.688 «significant at the .05 level of confidence ««purchased from Auditec and used for research only played less than 3 times Page 21 Table 5 F Values for Scheffe Test for Differences Between Conditions Tape 8** Left— Competing (LC) RightCompeting (RC) LeftCompeting RightNoncompeting 1.200* Right— Noncompeting (RNC) LeftNoncompeting (LNC) 0.413 1.300* 0.788 0.100 0.888 •significant at the .05 level of confidence ••purchased from auditec and used for research only played less than 3 times Table 6 F Values for Scheffe Test for Differences Between Conditions Tape LeftCompeting (LC) RightCompeting (RC) LeftCompeting 1.175* 10** RightNoncompeting (RNC) LeftNoncompeting (LNC) 0.300 1.288* 0.875 0.113 RightNoncompeting *significant at the .05 level of confidence **borrowed from private practice 5-6 years old at time of analysis 0.988 Page Table 7 F Values for Scheffe Test for Right-Competing Condition Between Tape Differences 1 2 3 4 5 6 7 8 2 3 4 0.41 0.68 0.27 5 6 7 8 9 1.22 0.03 0.95 0.95 2.09* 1.45* 1.89* 0.21 0.81 0.44 0.54 1.68* 1.04* 1.48* 0. 4 8 0.54 0.71 0.27 0.68 0.34 0.52 1.02* 0.23 0.75 1.89* 1.25* 1.69* 1.25* 0.27 0.87 0.23 0.67 0.98 2.12* 1.48* 1.92* 1.14* 0.50 0.94 0.64 0.20 9 1 0 0.44 *significant at the .05 level of confidence Page Table 8 F Values for Scheffe Test for Left-Competing Condition Between Tape Differences 2 3 4 5 6 7 8 9 10 0.52 0.77 0.35 0.59 0.05 0.95 0.04 0.01 0.14 0.25 0.87 1.11* 0.57 0.43 0.56 0.51 0.38 1.12* 1.36* 0.82 0.18 0.81 0.76 0.63 0.24 0.30 1.30* 0.31 0.36 0.49 0.54 1.54* 0.55 0.60 0.73 6 1.00* 0.01 0.06 0.19 7 0.99 0.94 0.81 0.09 0.18 1 2 3 4 5 8 9 0.13 •significant at the .05 level of confidence Page Table 9 F Values for Scheffe Test for Right-Noncompeting Condition Between Tape Differences 2 1 3 4 5 6 7 8 9 1.05* 0.67 1.30* 0.54 0.82 1.92* 0.62 0. 2 4 0.87 0.11 0.39 1.49* 0.87 0.38 0.25 0.51 0.23 0.87 0.63 0.13 0.15 1.25* 0.63 1.16* 0.76 0.48 0.62 0.00 0.53 0.28 0.28 0.76 1.29* 7 1.10* 0.48 1.01* 8 0.62 2 3 4 5 6 0.43 I. 3 0 * 1 0 0.25 9 1.83* 1 .40* 0.78 0.09 0.53 •significant at the .05 level of confidence Page Table 10 F Values for Scheffe Test for Left-Noncompeting Condition Between Tape Differences 1 2 3 4 5 6 7 8 2 3 4 5 6 7 8 9 10 0.43 0.59 0.49 0.64 0.16 0.80 0.10 0.03 0.09 0.16 0.92 1.07* 0.79 0.37 0.53 0.46 0.34 1.08* 1.23* 0.85 0.21 0.69 0.62 0.50 0.15 0.33 1.29* 0.39 0.46 0.58 0.48 1.44* 0.54 0.62 0.73 0.96 0.06 0.13 0.25 0.90 0.83 0.71 0.07 0.19 0.12 9 •significant at the .05 level of confidence Page 27 Compiled ranges per item of each condition by list (see Table 11) reveal that in this sample, the largest ranges exist on List EC, while the smallest can be found on List C-EC. there are 6 It should be noted, however, that tapes of List EC and 2 tapes of Lists EE and C-EC in this study. Channel Effects. Differences between syllables recorded on Channel 1 and Channel 2 result in an ear bias, as all syllables presented to the right ear have been recorded on Channel 1 and all syllables presented to the left ear have been recorded on Channel 2. Channel 1 (right ear) has the greatest bias on 6 tapes while Channel 2 (left ear) has the greatest bias on 4 tapes (see Table 12). Tape #8 shows the greatest percentage of bias with the right ear being favored in nearly 80% of pairs (see Table 12). Overall ranges of the dichotic the (10) tapes for the conditions RC, LC, RNC and LNC are 8.5, 9.0, 10.5 and 9.0 respectively (see Appendix F). The maximum difference between the conditions RC and LC is 7.0 Between RC and RNC conditions, the maximum difference is 8.5 dB and the maximum difference between the conditions LC and LNC is 8.5 dB minimum dB. is 0.0 dB (see Table 13). and the In each of the cases, the minimum difference found among this sample is 0.0 dB. Page 28 Measurement Reliability and Validity. The maximum each syllable measured were RMS values clearly visible. Signal-to-noise ratios present on the recording with the most tape noise, Tape #2, were 2:1 the very of least (see Figure 3)» at Re-analysis of a tape at the end of a measurement session revealed a maximum error of 1.5 dB. In the vast majority of cases, however, readings were off by 0.0 to 0.5 dB. Harmonic Distortion. audiometer Harmonic distortion levels, obtained with the VU meter adjusted so that the output of the calibration tone at the earphone was 10 dB above the intensity level 0-VU meter setting (see generated using a "Procedure" section of this document), range from 155 to lOyt in this sample (see Table 14) Page 29 Table 11 Recording-Level Ranges* of Individual Test Items for Each Condition** by List COND LIST EC (6 Tapes) LIST EE (2 Tapes) LIST C-EC (2 Tapes) RC 0.5 - 5.0 0.0 - 3.0 0.0 - 0.5 LC 0.5 - 3.5 0.0 - 3.0 0.0 - 1.0 RNC 0.5 - 6.5 0.0 - 2.5 0.0 - 0.5 LNC 1.0 - 3.5 0.0 - 1.5 0.0 - 0.5 *Ranges in dB re: reference calibration tone **RC = Right-Competing LC = Left Competing RNC = Right-Noncompeting LNC = Left-Moncompeting Page 30 TABLE 12 Inter-Channel Differences* for Competing Syllables for Individual Tapes (#'s 1-10) Tape Channel 1>Channel 2 Channel 2>Channel 1 Equal 1 7 24 9 2 17 16 7 3 21 15 2 4 5 14 1 5 15 19 5 6 4 12 4 7 24 13 3 8 31 4 5 9 22 11 7 10 26 5 9 *represented by numbers of items Page 31 TABLE 13 Differences Between Syllable Recording Levels* for Conditions** by Tape TAPE #1 RC-LC RC-RNC LC-LNC TAPE #2 RC-LC RC-RNC LC-LNC TAPE #3 RC-LC RC-RNC LC-LNC TAPE #4 RC-LC RC-RNC LC-LNC TAPE #5 RC-LC RC-RNC LC-LNC TAPE #6 RC-LC RC-RNC LC-LNC LOW HIGH MAX. DIFF -4.5 -4.5 -2.5 +2.0 +5.0 +5.0 4.5 5.0 5.0 -3.5 -4.0 -2.5 +3.0 +4.0 +4.5 3.5 4.0 4.5 -4.0 -6.5 -8.0 +7.0 +7.5 +7.0 7.0 7.5 8.0 -3.5 -3.5 -3.0 +1.0 +4.5 +3.0 3.5 4.5 3.0 -3.5 -5.0 -2.5 +2.5 +5.0 +5.0 3.5 5.0 5.0 -4.0 -2.5 -3.0 +0.5 +4.5 +2.5 4.0 4.5 3.0 Page TABLE 13 (continued) TAPE #7 RC-LC RC-RNC LC-LNC TAPE #8 RC-LC RC-RNC LC-LNC TAPE #9 RC-LC RC-RNC LC-LNC TAPE #10 RC-LC RC-RNC LC-LNC -3.5 -5.5 -8.0 +6.5 +8.5 +6.0 6.5 8.5 8.0 -1.5 -2.5 -4.0 +4.0 +5.0 +4.0 4.0 5.0 4.0 -2.0 -4.0 -3.5 +3.0 +5.5 +4.0 3.0 5.0 4.0 — 1.0 -4.5 -4.0 +4.0 +6.5 +4.5 4.0 6.5 4.5 *Levels in dB re: reference calibration tone **Conditions: RC-LC = Right-Competing minus Left-Competing; RC-RNC = Right-Competing minus Right-NonCompeting LC-LNC = Left-Competing minus Left-Noncompeting Page 33 Table 14 Harmonic Distortion HARMONIC DISTORTION TAPE #1 < n TAPE #2 10% TAPE #3 2% TAPE #4 2.2% TAPE #5 2$ TAPE #6 2% TAPE #7 2% TAPE #8 1.8% TAPE #9 TAPE #10 < 1% 2% Page 34 Discussion The purpose of this study was to determine the reliability of recording levels of test items and measure levels of harmonic distortion on a sample of 10 recordings of the Staggered Spondaic Word results indicate that the null Levels of harmonic distortion violate tapes in a in this sample which were random specified tolerance limits (N.A.B.) on Tape #2, only. This particular tape was one two The hypothesis cannot be accepted as the recording levels vary both within and among the 10 manner. Test. of the dubbed by amateurs following unknown procedures. Since distortion levels on the rest of the tapes of this sample not even approach the level of distortion present on Tape #2, it seems safe to assume that the source of distortion in this case unique to Tape #2, Tape #2. therefore, remaining 9 distortion. by do tapes is a factor Any further discussion of harmonic distortion on is irrelevant demonstrate and will not between less than 1% and 2% harmonic Although these levels comply with the 3% be pursued. limit The stipulated N.A.B., the affects of 2% distortion on a dichotic task among normal listeners or listeners with damaged auditory systems is not known. Page 35 Bode and Kasten (1971) demonstrated normally-hearing subjects on a that of performance speech-discrimination significantly when 5% distortion was present. performance the normally-hearing of test decreased In a similar study of the listeners, Gionnini and Frazen (1978) found that the addition of less than 1% harmonic distortion to a test of speech discrimination reduced listener-scores by 10%. If all items in this sample were recorded 10 dB above the calibration tone effects of and if the distortion on speech recognition were the same for spondees presented in a partially-dichotic manner as they are for monosyllabic words, then one might conclude that low levels of distortion will reduce scores by at least 10%. tape are recorded at 10 dB above the calibration tone; up to 2.2% distortion. harmonic In this case, however, no more than 2 items per In view of that fact, the affects of low-level distortion on spondees recorded in a partially dichotic manner is not an issue in this question thus producing of study. distortion In affects, order however, to completely it would actually test subjects of various populations with a answer any be necessary to recording of the reliability and SSW whose electromagnetic characteristics are known. Katz's major concerns in developing the SSW validity. He reasoned that by employing were more reliable material, he could develop a test sensitive to central auditory which would be existing tests. more reliable and stimulus lesions would require less test time than Page 36 It is conceivable that when a test is produced in recorded form and utilizes relatively reliable stimulus material, there will be consistent test, re-test results. That is an assumption which is commonly held and it has been the assumption of Katz and others who have generated normative data for performance of various populations on the SSW. assumption, however, is valid only variables associated with the test. that in the That absence of uncontrolled The results of this study indicate a source of variability which has not been carefully controlled is in the reproduction of the SSW. Recording levels of monosyllables vary across tapes by as 10.5 dB, so that much on a given test tape, one syllable may be presented 10.5 dB higher than a syllable on another tape. Once the test has administered, the the listening as scorer been computes the percentage of error for each of conditions i.e., Right-competing, Left-competing, Right-noncompeting and Left-noncorapeting and adjusts them for peripheral hearing loss when appropriate. ear (RE), the Scores are then averaged for the right left ear (LE) and finally RE and LE scores are averaged together for total percentage of error. In addition to comparing the overall percentage of error against ranges for "normal, mildly abnormal, moderately abnormal" and "severely abnormal", the scorer also totals the number of errors when the right ear is stimulated first (REF) and compares them to the number of errors when the left ear is stimulated first (LEF) to determine if an order effect exists. Finally, the scorer compares the overall performance of the two ears, i.e., RC & RNC vs LC & LNC, to determine if an "ear effect" is present. Page 37 In the event of inter-channel recording-level discrepancies such as those found in this study (see Table 12), interaural differences are effected. The degree of channel/ear bias random manner varies in a from item to item within a tape as well as between tapes as does the magnitude of the effect. conditions intensity on Tape #8, For example, for the competing the right ear is favored in nearly 80% of the items while on Tape #1, the right ear is favored only 18% of the time in the competing This constitutes a 12% difference between RC condition. conditions on the two tapes. percentage of error for Not only could these differences alter the each ear, but they could greatly affect the outcomes of other scoring procedures, as well. Since all for the left advantage or ear and the disadvantage disadvantage for the right for one corresponding ear are channel ear. presentations on separate channels, an is In an the advantage case of Tape #8, inter-channel differences could be responsible for a false RE effect mask a true could occur. focus on conditions, complex and LE effect. the of effects highly or In the case of Tape #1, however, the opposite Because of the rather involved performance or individual of scoring ears recording-level unpredictable; under procedures various discrepancies especially which listening are very since the patterns of these discrepancies vary from tape to tape. Of this sample of 10, 6 tapes were purchased new from this study and 4 others were borrowed from Auditec for clinics and a private practice. Comparison among tapes obtained directly from Auditec reveals significant differences among that group (see Tables 2,3 & 4) as well as Page 38 a main effect for individual listening conditions, while the condition responsible for the particular main effect varies by tape (see Tables 2-6 ). As decibel values of the interaural intensity levels vary, one wonders at what level differences affect listener performance, and how. The actual effects of roughly-controlled dichotic been In documented. interaural intensity differences on speech tasks, such as in the SSW, have not dichotic tasks utilizing carefully-controlled speech (e.g., consonant-vowel syllables), however, a 5-dB attenuation is sufficient to reduce Bissonette, 1975; RE performance in normals by 14% (Speaks & Berlin, Lowe-Bell, Cullen & Thompson, 1973). Results of other studies utilizing carefully controlled dichotic shown differences are highly by interaural that dependent affects upon such of interaural factors as intensity the method stimuli which have differences are accomplished (i.e., RE attenuation, RE amplification, LE attenuation and LE amplification) as the methods do not yield complimentary results (Speaks & Bissonette, 1975). In light of this information, it is clear that it is very difficult to accurately predict exactly how discrepancies sample of 10 tapes will affect listener performance. interaural intensity differences even as much identified in this It is likely as 10.5 dB, will not affect the performance of normal listeners, but it is unknown how differences systems. may affect abnormal listeners that these who have damaged auditory Page 39 Traditionally, based on a sample size of attempt to make 10, researchers generalizations about a much However, upon speculation, it seems likely that observed larger given do not population. the variability here, a larger sample might yield even greater discrepancies. It has been the case in this study that the larger the sample the larger the range of recording levels (see Table 11). that this study happened to which, for some obtain six reason, demonstrate It seems highly unlikely tapes random directly from Auditec variablity in recording levels which is not present on other tapes. Users of the SSW may be well-advised of normative data. Researchers who have argued about competing tapes they are determine characteristics of the to the recording using and generate their own the onset-alignment syllables may also wish to consider the possibility that, while the differences among results which they have observed may be result of different measurement procedures or measurement error, they may also be reflecting a difference among the producer of the SSW the tapes, themselves. has made no claim to the contrary. The In fact, the only claim which Auditec makes about their recordings is that they are violated any dubbed from "high-quality" recordings. Although Auditec has apparently broken no laws, regulations Association; adopted they by are the American distributing nor Speech, Hearing a product with and Language demonstrated quality-control problems which is used as a diagnostic tool. In view of that fact, it is essential that specific information about the recording characteristics of the tapes be made available to the diagnostician. In Page 40 addition, information recording in order concerning the proper care and usage of a to maintain the specified characteristics could be very helpful to the consumer. Page 41 Conclusion In conclusion the findings of this study levels of individual indicate that recording monosyllables on the SSW (lists EC, C-EC and EE) vary by as much as 10.5 dB with no discernable patterns in the direction or magnitude of intensity differences. The random nature discrepancies between tapes, items and listening conditions make it very difficult accurately predict listener performance patterns. Close adherence to recommended scoring procedures and available normative data in mis-diagnoses to may result or different diagnoses, depending on the tape used to evaluate the patient. Page 42 REFERENCES AMERICAN NATIONAL STANDARDS INSTITUTE. Specifications for audiometers (S3.6-1978). New York, New York: Acoustical Society of America, 1978. AMERMAN, J. and PARNELL, M. The staggered spondaic word test: a Normative investigation of older adults. Ear and Hearing, 1980, 2? 42-45. ARCISZEWSKI, R. The effects of visual perception training on the perception ability and reading achievement of first grade students. Dissertation Abstracts, 29 (12 A), 4174, 1969 In J. Northern and M.Downs (eds.) Hearing iji children. 2nd ed. Baltimore: The Williams & Wilkins Company, 197^1 ARNST, D. Overview of the staggered spondaic word test and the competing environmental sounds test. In D. Arnst and J. Katz (eds.) Central auditory assessment ; The SSW test, development and clinical use. 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AND HUGHES, G., Auditory processing tests for children: Normative and clinical results on the SSW test. Journal of Speech and Hearing Disorders. 1984. 49, 318-325. Page 43 BOCCA, E. Factors influencing binaural integration of periodically switched messages. Acta Otolaryngologica, 1961, 5^, 142-144. BOCCA E., CALEARO, C., CASSIMARI, V. and "cortical" hearing in temporal Otolaryngologica, 1955, 45, 289-304. MIGLIAVACCA, F. Testing lobe tumours. Acta BODE, D. AND KASTEN, R. Hearing and distortion and consonant identification. Journal of Speech and Hearing Research, 1981, j4, 323-331. BRUNT, M. The staggered spondaic word test. In J. Katz (ed.) Handbook of clinical audiology (2nd ed.) Baltimore: The Williams & Wilkins Co., 1978. BYRNE, P. and LESTER, L. Psychoeducational correlates of central auditory processing dysfunction. In E. Lasky and J. Katz (eds.) Central auditory processing disorders. Baltimore: University Park Press, 1 9 8 3 . CARVER, W. 1983. 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Kauffman and D. Hallahan (eds.) Handbook of special education. Englewood Cliffs, N.J.: Prentice-Hall, Inc., 1981. HODGSON, W. Basic audiologlc Wilkins Co., 1980 evaluation. Baltimore: Williams & JACOBS, J. et aJL. A followup evaluation of the frostig visual perception training program. Education Leadership Research Supplement. 169-175, November, 19681 In J. Northern and M. Downs Hearing in children. (2nd ed.) Baltimore: The Williams & Wilkins Co., 197S~ JERGER, J. and JERGER S. Clinical validity of central auditory Scandinavian Audiology, 1975, 4,147-163- tests. JERGER, S. and JERGER, J. Diagnostic value of crossed versus uncrossed acoustic reflexes. Archives of Otolaryngology, 1977, 103, 445-453JOHNSON, D. Preliminary analysis of ssw test and ces test data in 7 normal and 13 learning disabled school children 6-9 years old. In D. Arnst and J. Katz (eds.) Central auditory assessment; The ssw test, development and clinical use. San Diego: College Hill Press, 1 9 8 2 , KATZ, J. 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Speech, language and hearing Vol. Ill (Hearing Disorders) Philadelphia: W.B. Saunders, Co., 1982. . Central auditory dysfunction. New York: Grune & Stratton, 1977. KEITH, R. Tests of central auditory function. In R. Roeser and M. Downs (eds.) Auditory disorders in school children. New York: Thieme-Stratton, Inc., 1981. KUSHNER, D., JOHNSON, D. and STEVENS, J. Use of ssw/ces tests for identifying children with learning disabilities. Paper presented at the annual Convention of the American Speech and Hearing Association, 1977, Chicago, Illinois. In D. Arnst and J. Katz (eds.) Central auditory assessment: The SSW test, development and clinical use. San Diego: College Hill Press, 1982. LARSON, C. and PFINGST, B. Neuroanatomic basis of hearing and speech. In N. Lass, L. McReynolds, J. Northern and D. Yoder (eds.) Speech, language and hearing. Vol 1 (Normal Processes) Philadelphia: W.B. Saunders, Co., 1982. LASKY, E. Parameters affecting auditory processing. In E. J. Katz (eds.) Central auditory processing disorders. University Park Press, 1983. Lasky and Baltimore: LASKY, E. and KATZ, J. Perspectives on central auditory processing. In E. Lasky and J. Katz (eds.) Central auditory Processing disorders.. Baltimore: University Park Press, 1983. LEWIS, T. and WINKELAAR, R. Identification of central auditory dysfunction in children with learning disabilities. In D. Arnst and J. Katz (eds.) Central auditory assessment: The SSW test, development and clinical use. San Diego; College Hill Press, 1982. Page 46 LEHISTE, I. Suprasegmental features of speech. In N. Lass (ed.) Contemporary issues in experimental phonetics. Mew York: Academic Press, 1976. LIDEN, G. and KORSAM-BEMGSTON, W. Audiometric manifestations retrocochlear lesions. Scandinavian Audiology, 1973» 2, 29. of LOWE, A. and CAMPBELL, R. Temporal discrimination in aphasoid and normal children. Journal of Speech and Hearing Research, 1965, 8, 313-314. In E. Lasky and J. Katz (eds.) Central auditory processing disorders. Baltimore: University Park Press, 1 9 8 3 . LUBERT, N. Auditory perceptual impairments in children with specific language disorders; A review of the literature. Journal of Speech and Hearing Disorders, 1981, 3-9. LUDLOW, C., CUDAHY, E., BASSICH, C. and BROWN, G. Auditory processing skills of hyperactive, language-impaired and reading disabled boys. In E. Lasky and J. Katz (eds.) Central auditory processing disorders. Baltimore: University Park Press, I 9 8 3 . LUKUS, J. and ESCHENHEIMER, 0. Performance of learning disabled children " and language handicapped children on central auditory tests. Paper presented at the annual Convention of the American Speech, Hearing and Language Association, 1978, San Francisco. In D. Arnst and J. Katz (eds.) Central auditory assessment ; The SSW test, development and clinical use. San Diego; College Hill Press, 1 9 8 2 . MARTIN, L. and CLARK, J. Audiologic detection of auditory processing disorders in children. Journal of the American Audiologic Society, 1977, 2' 140-146. In J. Northern and M. Downs Hearing ^ children. (2nd ed.) Baltimore: The Williams & Wilkins Co., 1978. MARTIN, F. and FORBIS, N. The present status of audiometric practice: A follow-up study. American Speech and Hearing Association, 1978, 22. MATHIES, M. and GARSTECKI, D. Normal adult performance on a temporally modified staggered spondaic word test. Scandinavian Audiology , 1980, 9, 89-92. MILLER, G. The magical number seven plus or minus two: Some limits on our capacity for processing information. Psychological Review, 1956, 6^, 81-96. MUELLER, G., SEDGE, R. and SALAZAR, A. SSW results in head injury: Preliminary report of 200 cases. Paper presented at the annual convention of the American Speech-Language-Hearing Association, Cleveland, Ohio, November, I 9 8 3 . Page 47 MUSIEK, F. and GEURKINK, M. Auditory perceptual problems in children: Considerations for the otolaryngologist and audiologist. Laryngoscope, 1980, 90, 962-971. MUSIEK, R. and MORGAN, G. The use of central auditory tests in a of vasculitis. Ear and Hearing, 1981, 2, 100-102. case MUSIEK, R. and WILSON, D. SSW and dichotic digits results pre- and post-commissurotomy: A case report. Journal of Speech and Hearing Disorders, 1979, M. N.A.B. Standard magnetic tape recording and reproducing (reel-to-reel). Washington, D.C.: National Association of Broadcasters, Engineering Dept., 1965. NOFFSINGER, P. and KURDZIEL, S. Assessment of central auditory lesions. In W. Rintelmann (ed.) Hearing assessment. Baltimore: University Park Press, 1979. NORTHERN, J. and DOWNS, M. Hearing in children. (2nd ed.) Baltimore: The Williams & Wilkins Co., 1978. OTTO, W. and JOHNSON, M. Central auditory function, language/learning disabilities and the adolescent male. Paper presented at the annual convention of the American Speech-Language-Hearing Association, Cleveland, Ohio, November, 1983 REES, N. Auditory processing factors in language disorders: the view from procrustes bed. Journal of Speech and Hearing Disorders, 1973, M, 304-315. RUDMIN, F. SSW study alignment weaknesses. (letter Scandinavian Audlology, 1981, jO, 269-270. to the editor) RUDMIN, F. and KATZ, J. Dichotic onset and offset parameter n the ssw test. In D. Arnst and J. Katz (eds.) Central auditory assessment: The SSW test, development and clinical use. San Diego: College Hill Press, 1982. SHEA, S. and RAFFIN, M. Assessment of electromagnetic characteristics of the willeford central auditory processing test battery. Journal of Speech and Hearing Research, 1983, 26, 18-21. SPEAKS, C. and BISSONETTE, L. Interaural-intensive differences and dichotic listening. Journal of the Auditory Society of America 1975, 58, 893-898. SPEAKS, C. and JERGER, G. identification. Journal 185-194. Method for measurement of speech of Speech and Hearing Research, 1965. 8, Page 48 SPITZER, J. and ÏENTRY, I. Central auditory dysfunction among chronic alcoholics. Archives of Otolaryngology, 1980, 106, 224-229. TALLAL, P. Auditory processing disorders in children. In P. Lewiston and C. Sloan (eds.) Auditory processing and language-Clinical and research prospectives. Grune & Stratton, New York, 1980 In J. Duchan & J. Katz Language and auditory processing. In E. Lasky & J. Katz (eds.) Centralauditory processing disorders. Baltimore: University Park Press, 1983. TALLAL, P. and NEWCOMBE, F. Impairment of auditory perception and language comprehension in dysphasia. Brain and language, 1978, 5, 3-24 In Lasky, E. Parameters affecting auditory processing. In E. Lasky and J. Katz (eds.) Central auditory processing disorders. Baltimore: University Park Press, 1933% TALLAL, P. and PIERCY, M. Developmental aphasia, rate of auditory processing and selective impairment of consonant perception. Neuropsychologica, 1974, _12, 83-93, In E. Lasky and J. Katz (eds.) Central Auditory Processing Disorders. Baltimore: University Park Press, 1983. WELSH, L., WELSH, J. and HEALY, M. Central auditory dyslexia. Laryngoscope, 1980, 90, 972-984. testing and WETHERBY, A., KOEGEL, R. and MENDEL, M. Central auditory nervous system dysfunction in echolalic autistic individuals. Journal of Speech and Hearing Research, 1981, 420-429. WILLEFORD, J. Central auditory function in children with learning disabilities. Audiology and Hearing Education , 1976, 2, 12-20. WILLEFORD, J. Assessing central auditory behavior in children wslh learning disabilities: A test battery approach. In Keith, R. (ed.) Central auditory dysfunction. New York: Grune& Stratton, Inc., 1977, 43-72 YOUNG, E. and TRACY, J. An experimental short form of the staggered spondaic word list for learning disabled children. Audiology and Hearing Education, 1977, 3, 7, December/January. ZACK, L. and KAUFMAN, J. How adequate is the concept of perceptual deficit for education. Journal of Learning Disabilities, 5, 351-356, 1972, In J. Northern and M. Downs, Hearing in children. (2nd ed.) Baltimore: The Williams & Wilkins Co., 1978. ZIGMUND, N. Maturation of auditory processes in children with learning disabilities. In L. Tarnpol (ed.) Introduction to learning disabilities. Springfield Illinois: Charles C." Thomas, 1973 In J. Northern & M. Downs (eds.) Hearing in children. (2nd ed.) Baltimore: The Williams & Wilkins Co., 1978. Page 49 APPENDIX A Central Auditory Function: The Process and Tests Designed to Evaluate It The terms "central auditory function" as well as "central auditory ability, central auditory perception" and "central auditory processing" are used interchangeably in the literature to refer to particular and functions involved in hearing (Keith, auditory signal travels through the middle- and the haircells of the organ of Corti, 1982). is described as When an incoming inner-ear and reaches the mechanical nature of the signal, thus far, gives way to an electrical impulse. hearing sites Up to this point, "peripheral" and beyond it as "central." The signal leaves the inner-ear via the cochlear branch of cranial nerve VIII and enters the brainstem, where it arrives first at the cell bodies of the cochlear nuclei (Goldstein, 1982; The physiology operates in a of the highly auditory fairly simple fashion; does not (Goldstein, 1982). a central Larson & Pfingst, 1982). nervous system (CANS) a nerve cell either fires or it Anatomically, however, the system complex, intricate presents pathway of contralateral and ipsilateral ascending and descending fibers, some of which sysnapse early (Beasley & Page 50 Rintelmann, 1979) or leave the auditory pathway to travel in another sensory or motor pathway (Beasley & Rintelmann,1979; Goldstein, Other fibers share Pfingst, 1982; information 1982). with contralateral pathways (Larson & Goldstein) and still others are purported to act as "rapid transporters" between integrating centers (Goldstein, 1982) after they leave the superior olivary complex. Traditional psycholinguistic measures used in assessing hearing are network of redundancy insensitive neural of to central auditory disorders due to the vast intercommunication (Katz, 1962). The intrinsic the CANS which makes a breakdown less likely, also makes discrete testing of the system more difficult. assessing peripheral central auditory function Therefore, lies in the reducing key to extrinsic redundancy present in the stimulus itself (Beasley & Rintelmann, 1979), thereby placing greater stress upon the CANS. In the 1950's, researchers began developing techniques for reducing extrinsic redundancy normally order to challenge the (Keith, 1982). In involved in the processing of speech in system 1955, to to limits of normal functioning Bocca and his associates first demonstrated this phenomenon by administering speech the a test of sensitized or difficult a group of patients with temporal lobe tumors, and also to a control group. The control group experienced little difficulty with the test, while and others difficult the tumor group performed poorly. provided speech the ground tests and work their for The early work of Bocca further usefulness auditory dysfunction (Katz, Basil & Smith, 1963). in investigation detecting of central Page 51 Reduction of stimulus redundancy may be accomplished by introducing a competing stimulus or by altering the message itself (Miller, 1956; Moffsinger & Kurdziel, 1979). auditory function in There are numerous tests of central use today which utilize monosyllables, spondees, sentences, nonsense sentences, consonant-vowel syllables as pure-tones as stimuli. well as These stimuli may be altered by increasing or decreasing content length, filtering or reducing the frequency spectrum, introducing interruptions, or temporally manipulating the message. While the primary message is intact, competition may be in the forms of white noise, narrow-band noise, cafeteria noise and sentences (Noffsinger & Kurdziel, 1979; be presented monotically (one dichotically (both independent ears introduced ear receiving Keith, 1982). receiving different one Test stimuli may or more signals), signals generated from delivery channels) or binaurally (the same stimulus to both ears, simultaneously) (Noffsinger & Kurdziel, 1979). The listener is required to repeat or indicate (by pointing to a picture) the primary or altered stimulus. make judgments Most tasks involving tones require about perceived location of the the emergence tone or the listener to and disappearance of a tone, the relative loudness of two tones (Noffsinger & Kurdziel, 1979). Objective tests of central auditory function or those which do require listener thresholds and participation, decay and include tests electrophysiologic of Stapedial assessment. not reflex Stapedial reflex tests are very sensitive to lesions of cranial nerve VIII and are useful in differentiating between peripheral and central pathology Page 52 (Liden & Korsan-Bengston, 1973» Johnson, 1977; Jerger & Jerger, 1977; Moffsinger & Kurdzlel, 1979). Electrophysiologic neuroelectric potentials using electrodes placed electrical assessment potentials also on is carried out by measuring called auditory evoked potentials (AEP) the head. The AEP consists of minute which are generated by activity of cranial nerve VIII and the brainstem in response to click stimuli (Keith, 1982). Responses to multiple stimuli are amplified and averaged by a computer. Results analyzing are the interpreted latency of by the comparing AEP's between ears averaged response (Keith, 1982). and Most authors recommend administering subjective as well as objective tests of CANS integrity as diagnostic measure. part of a battery of tests, rather than as a single Page 53 APPENDIX B The Staggered Spondaic Word Test The SSW is a recorded test designed to measure the integrity of the CANS. Recordings are produced by Auditec of St. Louis and are available commercially. Numerous versions of the SSW, utilizing different word lists, have been produced. Auditec catalog. by Presently there are three test forms listed in the They are lists EC, C-EC and EE. List EC was described Katz (1968) as the most useful clinical tape because of its "clear speech" and "good signal-to-noise ratio." List C-EC is comprised of 20 items of list EC which are to have the simplest vocabulary and is therefore considered to be more appropriate for small children (Katz, dubbed considered 1968). List EC and C-EC are by Auditec from originals which were produced by Katz in his own facility. He has commented that although many different tapes have been Page 54 produced, using different equipment, techniques and speakers, "there is considerable similarity among the various recordings" (Katz, 1968). List EE is reportedly considered very similar to list 1984). EC (Carver, Its original, however was produced by Auditec in their studios. When asked to compare EC to EE, Carver (1984) described tapes of test EC as "very noisy" and "full of thumps;" and tapes of EE as having "less noise." He reported that Katz still advocates use of list EC over EE. The test consists of either recorded on one portion a of twenty or forty pairs of spondees two-track tape in a partially-competing manner, so that each test item is presented dichotically or with different monosyllables arriving at each ear, simultaneously (see Figure B1). In the first example in Figure I, the listener is presented "up" in the right ear, then "stairs" in the right ear and "down" in the left ear, simultaneously; and finally, "town" in the left ear. with In this example, the right ear receives the leading spondee, while in the second example, the left ear receives the alternate throughout leading spondee. These sequences the test and are referred to as "right-ear-first" (REF) and "left-ear-first" (LEF) conditions. The items are further referring ear only; presented to the designated as "right-noncompeting" (RNC), monosyllables presented monotically, or to the right "left-competing" (LC), referring dichotically to the left referring to the monosyllable presented ear; to the monosyllable "right-competing" (RC), Page 55 dichoticâlly to the right ear; and "left-noncompeting" (LNC), referring to the syllable presented monotlcally to the left ear. Figure B1 Example of Two Test Items 1. Right Ear Left 2. up stairs Ear down town Right Ear in law Left Ear out Time side Page 57 The listener is instructed as follows; 1. "Groups of words will be presented to one or both ears. 2. Respond by repeating the entire group of words presented. 3. Guessing is permitted."* Listeners are given four practice items at the beginning of the test. Scoring A response form is provided on which the forty paired items are listed with space provided for the scorer to evaluate each response (see Table B1). analyzed SSW scores are based on in terms of the number two response patterns: of errors which "ear effect" and "order effect." Ear effect reflects errors made in the REF compared to the sequences. Significant ear of errors lagging spondee. errors on the LEF effect exists when the difference between REF and LEF errors equals or exceeds five. number are Order effect refers to the made on the leading spondee compared to those on the Significant order effect is present when the number of leading compared to number of errors on the lagging spondee equals or exceeds five. * reprinted from D. and Arnst, Overview of the staggered spondaic word test the competing environmental sounds test. (eds.).Central auditory clinical use. assessment; San Diego; In: The SSW D. Arnst & J. Katz test, development College Hill Press, 1982. and Page 58 The scorer also notes the order in repeated; although sequences which other "reversals," are not considered errors. the than monosyllables those were presented, or A test item with two or more errors, despite sequence change, cannot be counted as a reversal. The three response patterns - ear effect, order effect and reversals known collectively - are as "response bias." Scores are plotted on the graph to form an "SSW-gram" which illustrates response bias (see Figure B2). Interpretation All aspects of the SSW are to be evaluated together and interpreted in the context of a complete audiometric test battery. stressed that SSW test results reflect an than lesion-specific pathology. area of Arnst (1982) dysfunction rather Page TABLE B1 SSW Scoring Symbols* Response 1. 2. No error on any word All mistakes (except word order) 3 . Word omission 4. Substitution 5. Distortion 6. Patient indicates the presence of a word but cannot repeat the stimulus 7 . Addition or omission of a final "s" 8. Different word order 9. Reversal 10. Intrusive word (patient adds extra word to stimulus sequence) 11. Need to replay stimulus item Marking Dot (.) in error column Draw a horizontal line through word Dash above word omitted Write in substitution above stimulus word Write in distortion above stimulus word Enter DK above stimulus word No error; diagonal mark (/) through sound omitted or at place where sound added No error; enter numbers (1-2-3-4) indicating order in which patient repeated stimuli below stimulus words No error; abnormal word sequence and no more than one error in the stimulus sequence: indicate reversal in REV column on score sheet No error; insert a caret where the word was added and write word above symbol (e.g., "cat") No error; enter R in stimulus I.D. number box Page 60 Table B1 (continued) 12. Fast start; quick response 13. Delay in response Mo error; enter Q in stimulus I.O. number box occurred Mo error; insert X to indicate where delay occurred If an item was scored correctly, circle the word and indicate "OK." •reprinted from D. and the competing Arnst, Overview of the staggered spondaic word environmental sounds test. (eds.) Central auditory assessment; clinical use. San Diego: The SSW In D. Arnst & J. test, development College Hill Press, 1982, p. 13 test Katz and Page 61 FIGURE B2 SSW-Gram* 100 75 100 I I I I I I I I + + + + I I I I I I X ^0 25 75 5^ +————— + — X I -+ 25 I 0 X + + Right NC C C Left NC X = R-SSW 0 = C-SSW A = A-SSW •reprinted from D. Arnst, Overview of the staggered spondaic word test and the competing environmental sounds test. In D. Arnst & J. Katz (eds.) Central auditory assessment; The SSW test, development and clinical use. San Diego: College Hill Press, 1982, p. 29- Page 62 APPENDIX C The Association Between Learning Disabilities and Central Auditory Processing Disorders A child who possesses average or above average been exposed to appropriate intellect and has learning experiences for his/her age and ability, but fails to achieve commensurate with his/her age and ability, often is labelled as "learning disabled, language disordered, dyslexic" or as having a "central auditory processing problem (Hallahan & 1981). seems The to particular depend a label great Bryan, which is applied to an individual child deal upon the bias of the examiner (psychologists, special education teachers, speech-language pathologists or audiologists) and the measurement tool(s) with the child (Duchan & Katz, 1983). which they The labels mentioned are the most current in use today and comprise only a few of a long list been evaluate which have used and rejected by investigators striving to accurately describe behaviors or define symptoms which are observed in children experiencing Page 63 learning difficulties. The incidence, or perhaps the identification of these behaviors and symptoms has been increasing among with learning problems, although they (Ludlow, Cudahy, Bassich & Brown, 1983; are school children not unique to this group Johnson, 1982; Keith, 1981). Many authors stress that the increase in learning disorders has grown in direct proportion to the growth of knowledge and technology as increased 1978; emphasis Keith, Disabilities well as on "keeping-up-with-one's-peers" (Northern & Downs, 1981). The Association for Children with Learning estimated in 1981 that there were between 8 and 12 million children in the United States who are "learning disabled" (Keith, 1981). The terra "learning disability" generally refers to a which one or more understanding or in manifest itself of using the "disorder in basic psychological processes involved in language; spoken or written, which may in an imperfect ability to listen, think, speak, read, write, spell or do mathematical calculations" (Hallahan & Bryan, 1981). Page 64 This includes conditions which handicaps, brain injury, have minimal developmental aphasia and excludes result of visual, hearing environmental, cultural or been or referred brain problems motor economic to as perceptual dysfunction,, dyslexia and which are handicaps; primarily the mental retardation disadvantage (Hallahan & Bryan, 1981). The terms "central perception, central auditory auditory refer to the "manipulation and central processing, central auditory ability" and "central auditory function" utilization nervous system..." (Lasky & of sound Katz). signals by the (see also Appendix A). Various authors have broken down the process into specific subprocesses or "auditory abilities" which they have determined to be necessary for a child to learn auditorily, including those listed 1981). A child who experiences difficulty in diminished learning hearing, even though peripheral auditory sensitivity is normal, is said to have a perceptual central disorder, auditory nonsensory processing auditory dysfunction, auditory deficit, auditory language disorder or an auditory processing problem (Keith, 1981). refer 4 (Keith, in one or more of these areas, and the difficulty (purportedly) results in through Table This does not to children with peripheral impairment who have failed to develop language or communication skills, but rather, to difficulties when they begin to use children who exhibit language for learning, despite normal intelligence (Lasky, 1983; Keith, 1981). Page 65 Often children who have been labelled "learning disabled" specifically, "dyslexic," characteristics. perform poorly Many on or "language investigators tests Newcombe, 1978; that some children 1981; Tallal, 1980; Tallal & Piercy, 1971; Lukas & Eschenheimer, 1978), Welsh, Welsh & Healy, and "learning disabled" (Byrne & Lester, 1983; Kuchner, Johnson & Stevens, 1977; 1981; found of central auditory processing who have been "dyslexic" (Cohen, 1980; Zigmund, 1973; 1980); more disordered" share similar have termed "language disordered" (Lubert, Tallal & or Young & Tracy, Dybka & Sansone, 1977; 1982; and Johnson, Enfield & Sherman, Lewis & Winkelaar, 1982 and Dempsey, 1977). Although cognitive the relationship processes in unclear, poorly when tested in one or interest among the more of linguistic, and fact that many children perform these areas has invited much on the part of investigators attempting to more clearly define the behaviors and characteristics of children problems (Lasky, 1983; Rees, 1973). have served as the basis upon which devised perceptual, demonstrating scholastic Often the results of these studies therapeutic procedures and implemented (Northern & Downs, 1978). have been This has taken place in the midst of much controversy concerning the inability of researchers to identify a disease scholastic failure, cognitive and the site-of-lesion questionable which is responsible for relationship among linguistic, perceptual abilities evaluated and their relationship to behaviors observed, as consequences or of well as intervention the reliability (Arciszewski, of 1969; tests and Jacobs, the 1968; Page 66 Northern & Downs, 1978; & Bell, 1982; Shea & Raffin, 1983; Rees, 1973; Bell & Raffin, 1983 Cohen, 1970; and Keith, 1981). Raffin, Shea Zack & Kaufman, 1972; Page TABLE CI Auditory Abilities Important to the Learning Process* Descriptive Term Discrimination Ability To differentiate among sounds of different frequency, duration or intensity Localization To localize the source of sound Auditory Attention To pay attention to auditory signals, especially speech, for an extended time Page 68 Table CI (continued) Auditory Figure To identify a primary speaker Ground from a background of noise Auditory Discrimination To discriminate among words and sounds that are acoustically similar Auditory Closure To understand the whole word or message when part is missing To synthesize isolated Auditory Blending phonemes into words Auditory Analysis To identify phonemes or morphemes Auditory Association To identify a sound with its source Auditory Memory; To store and recall auditory sequential memory stimuli of different length or number in exact order *from R. Keith, Tests of central auditory function. Downs (eds.) Auditory Thieme-Stratton, Inc. disorders 1981, p. 160 in In R.Roeser and M. school children. New York; Page 69 Appendix D1 List C-EC 1. day light lunch time 11. back door play ground 2. wash tub black board 12. school boy church bell 3. corn bread oat meal 13. snow white foot ball 4. bed spread mush room 14. ice land sweet cream 5. meat sauce base ball 15. hair net 6. black board air mail 16. fruit juice 7. house fly wood work 17. ash tray 8. green bean home land 18. nite light 9. sun day shoe shine 19. key chain suit case 10. white walls dog house tooth brush cup cake tin can yard stick 20. play ground bat boy Page 70 Appendix 02 List EC 1. up stairs down town 1 5 . back door 2. out side in law 1 6 . school boy 3 . day light 1 7 . snow white lunch time play ground church bell foot ball 4. wash tub black board 1 8 . band saw 5 . corn bread 1 9 . blue jay oat meal first aid black bird 29. day break lamp light 3 0 . door knob milk man 3 1 . bird cage crow's nest 3 2 . book shelf work day 33- book shelf drug store 6. bed spread mush room 20. ice land sweet cream 34. wood work beach craft 7 . flood gate 21. hair net tooth brush 35. hand ball milk shake 8. sea shore out side 22. fruit juice cup cake 3 6 . fish net 9 . meat sauce 2 3 . ash tray 3 7 . for give flash light base ball tin can sky line milk man 10. black board air mail 24. night light yard stick 3 8 . sheep skin 11. house fly wood work 2 5 . key chain 39. race horse street car 12. green bean home land 2 6 . play ground 13. sun day shoe shine 2 7 . corn starch 14. white house dog house 2 8 . birth day suit case bat boy soap flakes first place bull dog 40. green house string bean Page 71 Appendix D3 List EE 1. up stairs down town 1 5 . black board 2. work day church bell 1 6 . flood gate 3 . air port 1 7 . school boy jet plane air mail flash light church bell 4. play mate white house 1 8 . week end 5 . oil well 1 9 . cream pie mail man red cross work day 29. race horse street car 3 0 . day light lunch time 3 1 . snow white foot ball 32. white walls dog house 33" door knob cow bell 6. blue jay black bird 20. red cross street light 34. bird cage crows nest 7 . back door 21. out side in law 35. corn bread oat meal 8. mail man phone call 22. book shelf drug store 3 6 . back door 9 . meat sauce 2 3 . freight train 37. wood work beach craft wish bone base ball street car play ground 10. floor plan chalk board 24. fruit juice cup cake 3 8 . sun day 11. sea shore out side 2 5 . rail road 39. key chain suit case 12. night light yard stick 2 6 . wash tub 13. house fly wood work 2 7 . dish pan 14. corn starch soap flakes 2 8 . stop light hall way black board wet rag road sign shoe shine 40. head line watch band Page 72 Appendix E Playback Calibration of the Akai Tape Recorder HEAD ALIGNMENT Prior to output-level adjustments, the playback and reproduce heads of the tape recorder were aligned to allow maximum voltage in compliance with the National Association for Broadcasters (N.A.B., 1965) standard. This was accomplished using a Magnetic Reference Laboratory (M.R.L.) full-track, reproducer calibration tape (type #21T104) with a reference fluxivity of 200 nW/m. TAPE SPEED Tape speed was timed at 7.5 in/s with less than 0.3% which conforms with N.A.B. (1965) specifications. fluctuation FREQUENCY RESPONSE Frequency response of the tape recorder was optimezed using the M.R.L. calibration tape. The output of the tape recorder was fed to the input of an analyzer (Tektronix, type AA501, PC 984071) and the reproducer gain was adjusted at spot frequencies so that the output at frequencies measured fell within specified allowable limits (N.A.B., 1965) (see Table El). After the data were gathered, the frequency response of the tape recorder was characterized and output-level values obtained were found to be compliant with N.A.B. (1965) specifications. Comparison of tape recorder-output levels, before and after data acquisition, results in differences of no greater than +/- 0.5 dB at any reference frequency (see table E2). Page 73 Table El Frequency Response of Akai Tape Recorder Upon Intial Optimalization. FREQUENCY (Hz) 31.5 63 125 250 500 1000 2000 4000 8000 10,000 12,500 16,000 20,000 CHANNEL 1 (dB) + + + + + - 0.1 2.9 0.4 0.3 0.0 0.6 0.0 0.9 0.3 0.0 0.4 0.7 1.4 CHANNEL 2 (dB) + + + + + + - 0.3 3.7 0.2 0.4 0.0 0.5 0.1 1.1 0.6 0.1 0.0 0.3 0.4 Page 74 Table E2 Frequency Response Upon Final Characterization of Akai Tape Recorder. FREQUENCY (Hz) 31.5 63 125 250 500 1000 2000 4000 8000 10,000 12,500 16,000 20,000 CHANNEL 1 (dB) + + + + + + - 0.5 2.5 0.7 0.8 0.0 0.6 0.0 1.1 0.5 0.2 0.0 0.3 1.2 CHANNEL 2 (dB) + + + + + + + + - 0.4 3.7 0.2 0.4 0.0 0.5 0.2 1.1 0.7 0.2 0.3 0.4 0.4 Page 75 Appendix F1 Syllable Ranges per Item (in decibels) List EC (6 Tapes) *ranges in dB re: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 reference calibrations tone RC LC RNC LNC 5.0 1.5 3.0 3.5 2.5 5.0 3.0 4.0 3.0 4.5 3.0 3.0 4.0 3.0 2.0 4.0 5.0 2.5 1.0 2.0 2.0 2.0 2.5 1.0 2.5 1.5 2.0 2.0 1.0 1.5 1.5 2.0 1.0 2.0 1.5 2.0 2.0 3.5 1.5 2.0 1.0 1.5 1.0 1.0 1.5 2.0 1.5 1.5 1.0 2.0 2.5 1.5 1.5 1.0 1.5 1.5 1.0 1.5 1.5 1.0 1.5 0.5 4.0 1.5 3.5 1.0 1.0 2.5 3.5 2.5 2.0 2.5 3.0 2.5 1.5 4.0 2.0 3.5 5.0 3.0 5.0 4.5 2.5 2.5 2.5 6.5 0.5 3.5 3.5 3.5 2.0 2.5 2.0 5.5 2.5 2.0 1.0 1.5 1.5 1.5 1.0 2.0 1.5 2.5 3.5 2.5 2.0 1.0 2.0 1.5 2.0 1.0 2.0 1.5 1.5 1.5 2.5 1.5 1.0 2.0 1.5 1.0 1.0 1.5 1.0 1.5 1.0 2.0 2.0 1.0 1.5 2.0 0.5 0.5 2.0 1.0 Page Appendix F1 (continued) 35 36 37 38 39 40 1.0 2.0 0.5 1.0 1.5 1.5 1.5 0.5 1.0 1.0 1.5 1.5 2.0 2.0 1.0 1.5 1.0 1.0 1.0 1.5 2.0 2.0 1.0 1.5 Page 77 Appendix F2 Syllable Ranges per Item (in decibels) List C-EC (2 Tapes) •ranges in dB re: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 reference calibrations tone RC LC RNC LNC 0.0 0.5 0.5 0.5 0.0 0.5 0.0 0.5 0.0 0.5 0.5 0.0 0.0 0.0 0.5 0.5 0.0 0.0 0.5 0.5 0.5 1.0 0.5 0.5 0.0 0.5 0.0 0.5 0.0 0.5 0.0 0.5 0.0 0.5 0.0 0.0 0.5 0.5 0.5 0.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.5 0.0 0.0 0.0 0.0 0.0 0.5 0.5 0.0 0.5 0.5 0.5 0.5 0.5 0.0 0.5 0.5 0.5 0.0 0.5 0.5 1.0 1.0 0.0 0.5 0.5 0.4 0.5 0.5 0.0 0.5 0.5 Page 78 Appendix F3 Syllable Ranges per Item (in decibels) List EE (2 Tapes) *ranges in dB re: 1 2 3 4 5 6 J 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 reference calibrations tone RC LC RNC LNC 0.0 0.5 0.5 0.5 0.0 0.0 0.0 0.5 0.5 0.5 0.0 0.5 0.0 3.0 0.0 0.5 0.5 0.0 0.5 0.5 0.5 0.0 0.0 0.0 0.0 0.0 0.5 0.0 5.0 0.0 0.5 0,0 0.5 0.0 0.5 0.5 0.5 0.5 0.0 0.0 0.5 1.0 0.0 1.0 0.5 0.5 0.0 3.0 0.0 0.5 0.0 0.5 0.0 0.5 0.5 0.5 0.5 0.5 0.5 0.0 0.5 0.5 0.0 0.0 0.0 0.0 0.5 0.5 0.0 0.5 0.5 1.5 0.0 0.0 0.5 0.0 0.5 0.0 1.0 0.5 1.0 2.5 1.0 0.0 0.5 0.5 0.5 0.5 0.5 1.5 0.5 0.5 1.0 1.0 0.5 1.0 2.5 0.0 1.0 0.0 0.5 1.0 0.0 0.5 1.0 0.0 0.5 0.0 0.5 1.0 0.5 0.0 0.5 0.5 0.5 1.5 1.5 0.0 0.5 1.0 0.5 0.0 0.0 1.0 0.5 0.5 0.5 0.5 1.0 1.0 0.5 1.0 0.5 0.5 1.0 0.0 Page Appendix F3 (continued) 35 36 37 38 39 40 0.0 1.0 0.0 1.0 0.5 1.0 0.5 0.5 1.0 0.0 0.5 0.0 0.0 0.5 0.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.0 Page 80 APPENDIX G Instrument Settings When taking intensity level measurements, the tape recorder was set to "play-forward" and a speed of "7.5 cm/sec." The meter range of the beat frequency oscillator (BFO) was 80 dB set to SPL, the function selector to "1/3 octave", the range multiplier to "-30", the meter switch to "RMS", the input potentiometer at "9". On the graphic level recorder, the potentiometer range was "50 dB", the rectifier response was "100 mm/sec." and the to was on "RMS" and the lower limiting frequency was "20 Hz." The writing speed was "400 speed set mm/sec.", the paper drive shaft speed was set to "120 r.p.m." While recording, the input potentiometer setting ranged from "3" to "6" with an attenuator setting of "20." Page 81 When measuring harmonic distortion, the tape recorder was set to "play-forward" and a speed of "7.5 cm/sec." The audiometer was in "speech" mode, and set either on "channel 2" and "tape A" or "tape B". The attenuator dial was set to "70 dB HL" and the "interrupt" button was depressed. The meter function of the sound level meter (SLM, Bruel & type Kjaer, 2603) was set to "fast" with the weighting network at "linear" and the meter range from 25 to 105 dB. Output energy levels were noted recorded and by hand at the filter settings of "1000, 2000, 3100, 4000, and 5200." All instruments were set to power "on" at least 5 to gathering data. minutes prior