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Mr. Cain’s General Psychology Lecture Notes: Set #1 OVERVIEW: Psychology as a Science I. What is Psychology? Answered by looking at psychology’s history A. Historical Development: until the late 1800s psychology was a branch of philosophy. In philosophy, there were three major questions that had a significant affect on the development of psychology: 1. What is the Source of Knowledge? a. Rationalism: Reason is the source of knowledge and is superior to experience (Plato, Descarte) b. Empiricism: Knowledge is based on experience and observation (Locke, Hume) 2. What Process do we Obtain Knowledge? a. Rationalism believes in the doctrine of innate ideas. One needs to recover knowledge through logic and reason; senses fool us. b. Empiricist believe knowledge is obtained through the senses. When come into the world, the mind is a “tabula rosa”. Ideas enter the mind via the senses. Intellect functions by comparing ideas. Science developed out of the empirical tradition and psychology began using the scientific method. Therefore, psychology considers itself an empirical science. 3. What is the Nature of Man, the Knower? (Mind-Body problem):Introduced by the Greeks in the 6th-5th Century BC when they distinguished between the material and spiritual world. Plato solidified the split by claiming that man is made up of two parts (called dualism): a. Body- of this world b. Soul- supernatural part; lived before birth and knew Reality. In this life it is imprisoned in the body. In the 17th Century Descartes again firmly declared man had a dual nature. Body governed by the laws of mechanics; soul the source of life and independent of the body. Problem with Dualism: how do the body and soul/mind interact? British philosophy (Empiricism) emphasized experience as the source of knowledge. Although the basic sciences followed this route, psychology still a division of philosophy. B. Psychophysics Research in the mid-1800s: interested in sensation, stimulation, and perception such as vision, hearing and touch. Used measures to determine thresholds and “just noticeable differences”. C. Wundt: Is known as the father of psychology since, in 1879, he established the first psychology laboratory in Leipzig, Germany. He wanted to use the methods of psychophysics to study the mind. He intended to develop a new science which would discover the structure of the mind. 1. Asked the question “What is the Mind?”- what are its elements, parts. He attempted to apply the scientific method and attempted to be empirical. Used the method on introspection to study phenomena such as attention 2. Structuralism emerged from his approach. D. Functionalism developed in America in the 1890s and was a reaction against Structuralism. 1. Asked “What is the Mind For?”; interested in the function or purpose of the mind. 2. Behaviorism grew out of Functionalism E. Behaviorism (J. B. Watson): the most significant influence on American psychology and is reflected by the definition of psychology and the experimental orientation. 1. The only subject matter of psychology is behavior since only behavior can be observed and measured. 2. Denied mind since cannot be seen or measured. With B. F. Skinner, behaviorism evolved to S-R psychology. S-R psychology assumed that behavior starts with a stimulus and ends in a response; all behavior is in response to a stimulus. S-O-R psychology is a variation of S-R and considers the internal state of the organism is considered. The O refers to cognitive process- how persons think, understand and know about the world. A reaction to behaviorism is humanistic psychology. Emphasis on the whole person and argued against the analytic approach. Focus on human potential and personal development, free will or choice (vs. determinism) F. The Definition of Psychology: Out of this historical development, the definition of psychology emerges as: The scientific study of behavior and mental processes. The study of behavior and mental processes using the scientific method. 1. Behavior: activities of the individual intact organism that can be observed and measured. Since cannot deal with the totality of behavior, select out certain segments of behavior- called Responses 2. Behavior is in response to a Stimulus- environmental conditions That are present in any given behavioral situation. 3. Scientific Method is an approach to discover relationships between events; in psychology between environmental events and behavior. Steps of the method include: a. b. c. d. observe a chosen phenomena and collect certain facts note pattern among the facts find plausible explanations of the pattern- hypothesis make a prediction based on the hypothesis 2 e. check out the prediction experimentally. Experiment will either support or not support the hypothesis. EXAMPLE: At the beginning of the first therapy visit asked person what has improved between the phone call and the session. Therapist begins asking other clients and notes goals met in fewer sessions. Based on observations, designs a study comparing group asked the question vs. group that was not. Qualitative Research involves steps a-c above. Research methods include: 1. Naturalistic Observation: observe and measure in a naturalistic setting. Do not control or manipulate the situation. Does allow noting and descriptions of patterns. 2. Case Study: in depth study of a case or a few cases. May cite other reports of similar cases to generate an explanation or hypothesis. Archival methods may be used Quantitative Research conducts controlled observations or measures with larger groups of subjects. Quantitative procedures include: 1. Surveys, tests, and questionnaires 2. Experiment: conduct observations under conditions of stric control. a.Dependent Variable: what is observed or measured. In psychology, it is behavior; the R in S-R b. Independent Variable: what the experimenter controls or varies; the S in S-R. When conduct the experiment, need to describe the experimental procedure, including the experimenter’s behavior. Need to control for experimental bias. Methods include blinding the researcher. Random assignments of subjects to experimental and control groups: a.Control group is typically needed- a group that does not experience the experimental procedure. b.Placebo group may be necessary- subjects that receive an intervention that has no impact on what is being observed. c.Experimental group: receives the procedure EXAMPLE: The Hawthorne Study II. The Goals of Psychology A. To Understand Behavior: If have an adequate understanding then can put together a theory- a way of explaining the facts or observations. A theory is never true or false. Hypotheses are supported, not proven. B. To Predict Behavior: in science it is usually a probably statement (which explains the use of statistics). C. To Control Behavior 3 III. Current Key Issues A. B. C. Observable behavior Vs. Mental Processes Nature/Heredity vs. Nurture/Environment Individual Vs. Universal principles III. Fields of Psychology A. B. C. D. E. F. G. H. I. Experimental Psychology Comparative (animal) Physiological/Biopsychology (Brain, sensation and perception) Clinical and Counseling Psychology [Distinguish psychiatry and psychoanalysis] Developmental (includes child, adolescent, adult development) School and Educational Social and Ecological/Environmental Organizational and Industrial (Includes program evaluation) Health (Sports and Community) IV. Academic Preparation: Because of its academic tradition, Ph.D. or doctoral degree. V. The Bio Psycho Social Model: a perspective that is used in the social sciences: Bio: focus on biology, physiology, Psycho: internal psychological processes (cognitive, self/personality, motivation) Socio: environmental factors such as family, social systems, culture VII. Reading Psychology Research Articles: Because psychology assumes a research tradition, publications and presentations follow a standard format. Typically, a research article will be organized as follows: A.Introduction: Surveys the literature by covering previous findings and explanations about the findings. B.The question addressed: authors present why they are designing and conducting the study. Question comes out of the previous research. In this section the authors will present the hypothesis- a prediction of results based on the research literature. C.Participant/Subject selection and experimental procedures. Often will have a control and experimental group(s) and perhaps a placebo group. May describe how subjects were provided informed consent OR justification why subjects were not consented and perhaps deceived. D.Research design: explanation about the study design, including ethical considerations. May include “blinding” the participants and investigators. The design sets up the statistics used in analyzing data. 4 E Findings: Usually a statistical analysis. This analysis will statistically support or not support the hypothesis. (Most likely the criteria is a “p” value < .05: statistical significant in that chances are less than 5% that difference resulted by chance) F.Summary: usually of the statistical results and data analysis. Includes if the hypothesis was supported. G.Conclusions: how the findings fit into the existing literature. Also, may site limitations of the study and suggestions for future research. H.References: publications and presentations referenced in the article. When critiquing or evaluating a research study, ask the following questions: A.Who were the investigators? Also, does the study mention funding source or refer to conflict of interests. B.What is the aim or purpose of the study? Also, does the article say why the study is done- the question or hypothesis the study is to address. C.Who were the participants or subjects? Age or other exclusion criteria D.How did the investigator try to measure the topic of interest: by survey, questionnaires or tests. Or did they measure a specific behavior by counting (frequency) or measure duration, intensity or amount? Can you name the independent variable (what was manipulated by the researcher) and dependent variable (what was measured or observed)? E.What was the design of the study? What were the experimental groups (if any); was there a control or placebo group? F.What were the results and conclusions? G.Were there any ethical concerns? 5 BIOPSYCHOLOGY: The Biological Basis of Behavior Biopsychology and behavioral neuroscientists (including neurologists, biochemists, and pharmacists) study the relationships between physical structures and functions (such as the brain) and biochemistry on the one hand and behavior and experience on the other.Behavior and experience are biologically and physiologically based. I. The Neuron: nerve cells that are the basic unit of the nervous system. Dendrites Axon Cell body A. Teledendria (Terminal Buttons) Myelin Sheath Dendrites: are stimulated be neighboring neurons or physical stimuli. B. Axon: delivers nerve impulse to adjacent neurons or an effector (muscle). At the end of the axon are teledendria or terminal buttons. C. Myelin Sheath: specialized cells of fat and protein that surround the axon Information is sent via an electrical impulse that travels from the dendrites and through the axon. Same neuron can fire up to 1000 times/second. A. At its resting state, inside the cell is negatively charged; the outside positively charged- difference is approx -70 microvolts (mv). B. When stimulated, Na+ and K- ions permeate the membrane creating a positive charge of approx +30 mv. This change is called the Action Potential C. After firing, the charge goes below -70 microvolts before returning back to its resting state (or potential) D All-or-None Law: stimulus either causes the threshold to be reached or it does not. If threshold reached it fires. 1.firing depends on the characteristics of the neuron, not strength of the stimulus. 6 down 2.Absolute Refractory period: a period after the firing when it cannot fire. 3.Relative Refractory Period: can fire but only with a strong stimulation. II. The Synapse: a small gap (1 millionth an inch) between the teledendria and the next cell. dendrites of A. Neurotransmitters: When action potential reaches the end of the axon,chemicals called neurotransmitters are released that flow across the synapse and either excite or inhibit the next cell. If end result of these chemicals elevates the charge to -60mv, the cell will fire. Some neurotransmitters remain and either are washed away or return to the originating cell- reuptake. B. Types of Neurotransmitters 1. Acetylcholine (ACh): involved in muscle movement and cognitive functions, including memory. Alzheimer’s have a decrease in ACh. 2. Dopamine: Deficiency related to Parkinson’s; overproduction related with schizophrenia. 3. Serotonin: related to mood (depression), pain III. The Nervous System: the brain and neurons extending throughout the body. The components of the nervous system are as follows: The Nervous System Peripheral NS Somatic or Voluntary Sympathetic Central NS Autonomic or Involuntary Brain Spinal Cord Parasympathetic A. Peripheral: nerve cells outside the central nervous system (brain & spinal cord). Carries information to and from the Central Nervous System (CNS). 1. Sensory or afferent neurons carry input to the CNS 2. Motor or efferent neurons carry information out of the CNS 7 Two (functional) divisions of the peripheral NS: 1. Somatic (or voluntary): specializes in voluntary movement. Evaluates change in the external environment and carries sensory information and activates muscles. 2. Autonomic (or involuntary): movement outside our awareness; handles physiological processes inside the body (i.e. action of heart, lungs, blood vessels, glands, organs). Carries information about the internal environment. The autonomic is further divided into to divisions: 1. Sympathetic: mobilizes the body in stressful situations. 2. Parasympathetic: calms the body, slow responses down B.Central Nervous System: the brain and spinal cord OR all the nerve tissue enclosed by bone. Integrates information coming from the peripheral nervous system. 1. The Spinal Cord: if cut through the spinal cord would see columns of white matter nervous tissue which leave the cord at various points to form peripheral nerves. The reflect arc is the simplest behavioral sequence that is organized without direct participation of the brain. Sensory information is carried to the spinal cord. Stimulated neurons within the cord lead back and stimulate neurons that lead back to muscle cells. 2. The Brain: approx 3 lb; 10-14 billion cells. Have two hemispheres which explains the notion of Right-Brain/ Left Brain. It appears that the left side manages language and speech areas while the right handles non verbal processes such as pattern. If a person has damage to left side of brain, may be able to hum the tune (pattern) but won’t know the words. If damaged on right side, cannot hum tune but can say the words. Motor Strip Central Fissure Parietal lobe Frontal lobe Sensory Strip Occipital lobe Temporal lobe Lateral fissure THE CEREBRAL CORTEX 8 a. The Cerebral Cortex (“new brain”): Approx 6” thick covers most of the brain and related to higher mental abilities such as thinking, language, problem solving. The two sides (left-right) are connected by the corpus callosum. Cortex subdivided into lobes that have different functions: 1) Occipital: visual 2) Parietal: some speech areas and body sensations. For example, makes it possible to recognize an object by touch. Contains the “sensory strip” next to the central fissure 3) Temporal: auditory, memory of smell, visual processes. Damage can result in deficiency in processing visual information. 4) Frontal: mixture of functions involving higher mental processes- impulse control, time perception, problem solving. In front of the central fissure is the “motor strip” Associative Areas are across all areas of the cortex and combines processes across the various areas b.The Subcortex: below or underneath the cortex. Divided into several areas or structures: Limbic System Thalmus Hypothalmus Cerebellum Reticular Activating System Medulla Subcortical Mechanisms of the Brain 1.) The Central Core (“old brain”): controls basic functions a) The Hindbrain: medulla, cellebellum and reticular activating system (1) Medulla: vital functions- breathing, heartbeat, digestion (2) Cerebellum: posture, muscle coordination, muscle tone b) Reticular Activation System: central clearinghouse for coming to and from the brain. Gives priority for incoming information and excludes other information. Attention, sleep, arousal 9 c) Thalmus: Relay center to the cortex, especially sensory information (vision, auditory, taste, smell) d) Hypothalmus: maintains a steady bodily state or internal environment. Involved in survival (feeding / thirst, fight-flight, mating). Sensitive to changes in blood volume and concentration. Pleasure centers 2)Limbic System is above the central core and does involve the thalamus and hypothalamus. Various structures involved in emotions and motivation. Also, involved in learning and memory Sensation and Perception I. Basic Concepts and Principles: Psychophysics studies the relationship between physical aspects of the environment/stimuli and our experience of the stimuli. A.Sensation: sense organs receive information from the environment. B.Perception: “making sense of the senses”- sorting out, integrating, and interpreting sensory data. C.Absolute Threshold: stimulation must reach an absolute threshold for it to be detected. 1. Eye can detect a candle flame 30 miles away on a clear night 2. Ear can detect a ticking watch from 20 feet away. Determine the absolute threshold by using the method of Constant Stimulation: present the stimuli and determine the lowest magnitude person reports 50% of the time. D.Difference Threshold: the minimal difference in magnitude of two stimuli to tell apart 50% of the time- a just noticeable difference. 1. Varies between people 2. varies at different times during the day for the same person Although there are differences between individuals and intrasubject variations, there are so-called “laws” of psychophysics. Many of these “laws” were formulated by Weber so have Weber’s law or Weber’s Constant. 1.Weber’s Constant: difference of light intensity is 1/60th or approx. 2% - the amount of light must increase or decrease by 2% to note a difference 2.Weber’s Law: 1:50 ratio with weight. E.Signal Detection: depends on not only sensation, but also perception and other psychological processes. Detecting or noting signals depends on: 1. Quality of the sensory system 2. Noise: unwanted background signals that interfere 3. Learning, expectations, motivations F. Sensory Adaption: one adapts to the sensation 1 Become more sensitive to stimuli of low magnitude; for example in a dark room adjusting to the level of light. 2. Become less sensitive to constant stimuli. ; for example noise in the hall, smells. 10 II. Vision A.Light passes through the eye and eventually reaches the retina- a thin layer of nerve cells in the back of the eye. These cells convert light into information that enters the brain. Two types of receptors: 1. 2. Rods- very light sensitive; notes intensity (light-dark) Cones- responsible for color perception (red, green, blue) and focus B. Ganglion cells collect and summarize the information from the retina and move the information to the optic nerve. Optic nerve from each eye meet at the optic chiasm where the nerve splits: 1. 2. Impulses from the right side of EACH eye go to the right side of the brain Impulses from the left side of EACH eye go to the left side of each eye C.Feature Detection: as information is sent through the brain, certain neurons are triggered by certain features such as shape, width, pattern, movement. All this information is combined and processed and ends up as visual experience in the occipital lobe. III. Auditory/Hearing: Ear detects air wave patterns and this information is converted to neural information that spreads to auditory areas of the brain. Neurons in the cortex respond to specific aspects of sound- feature detection. IV. Perception: constructing and organizing the world; making sense of the senses. A.Gestalt psychology: Theories of perception influenced by Gestalt psychology- how information is organized into meaningful wholes. (Gestalt means pattern) B.Several Principles derived from the Gestalt tradition: (see Text, p. 114) 1. Closure: perceive whole figures when there are actually gaps 2. Similarly: group elements that are similar in appearance 3. Proximity: group elements that are close together. 4. Simplicity: tend to perceive pattern in a simple, straight forward manner. 5. Perceptual Constancy: objects perceived as constant or unchanging even though there is a change in stimulation: a. Size: see as the same size even though the retina image size changes according to distance. b.Color: seems the same even though light conditions change C.Feature analysis: although Gestalt psychologists emphasize pattern recognition, current research suggests that people do react to elements that make up the pattern; people engage in feature analysis. 1. Feature analysis theory claims people focus on parts first before create the whole pattern. 2. Feature analysis based on the fact that neurons detect specific features (feature diction). So the Part-Whole (Gestalt) argument continues as two different theories 11 1 Top-Down Processing: perception guided by higher-level knowledge. The role of experience, expectations, and motivation. 2.Bottom-Up Processing: perception guided by recognizing information about individual components of stimuli. Subliminal Perception and ESP: little research data to support these phenomena. Altered States of Consciousness I. Consciousness A. Issue of Measuring Consciousness- depends on how define consciousness B. How to Define Consciousness 1. Sensory Awareness: sensing allows us to be aware 2. Selective Attention: selecting stimulation that conscious of 3. Inner Awareness: conscious of thoughts, memories, emotions 4. Sense of Self: of being an individual 5. Waking State: so sleep and trance are altered states. C. Activation: our level of activation varies from extreme alertness and arousal to deep sleep. So in sleep one is still activated to some extent. II. Sleep: one is not unconscious since dreams are remembered and person is responsive to the environment. A. Brain Structures involved 1. RAS: RAS activates the cortex and controls pattern associated with level of arousal. So the RAS is involved in mechanisms of waking and sleeping. 2. Hypothalamus: lesions in the posterior (rear) of the hypothalamus cause sleep- monkeys will sleep continuously for 4-8 days and drowsy when awake. Anterior lesions prevent sleepmonkeys stay awake for several days, gradually become exhausted.Not a sleep area as much as involved in pathways of the RAS. B. Stages of Sleep: about 1/3 of life is spent sleeping. There appears to be four stages and people cycle 4-5 times throughout the night. First cycle is the longest but, as we go through the cycles, REM (Rapid Eye Movement ) lengthens (from 10 minutes in first cycle to 30 min during last). 1. Stage 1 (Light sleep; 30-40 min). Alpha waves on EEG. Will note REM. Little muscle movement. When enter stage 1 the first time (when falling asleep, do not dream) 2. Stage 2: deeper and have bursts of EEG activity 3. Stage 3: (approx 30 min) Delta waves appear.- one may talk in sleep and/or sleepwalk. 4. Stage 4: (Deep Sleep)- NREM; night terrors in this stage C. Dreaming: Usually dream 4-5 times a night with intervals about 90 min apart. Dreaming becomes longer as the night goes on. Again, associated with REM. Also, while dreaming, except for eyes, the body remains still. May have signs of sexual arousal. 12 1. Dream Deprivation: If people deprived of dreaming, they show memory lapses, difficulty concentrating, and anxiety may elevate. Also, when allowed to sleep, there is an increase in REM and dream activity. 2.Activation-Synthesis: theory that claims dreaming reflects a need for RAS activation and stimulation of sensory cortex. 3.Do Dreams have Meaning? Freud hypothesized the unconscious mind and thought that dreams reflected unconscious wishes and desires. However, minimal support for dreams reflecting unconscious desires. Instead, content like reflects current concerns and recent events. Consider dreaming as “thinking in pictures”. So translate feelings into a visual representationanxiety as falling; anger as a violent scene. III. Hypnotism/ Trance States: an altered state of consciousness. Although seen as unusual, trances states occur naturally, as in daydreaming or in an activity of intense attention so that are unaware of other events going on. A. Left Brain- Right Brain: some theorists conceptual trance/ hypnosis as a left-right brain functiondeactivating the left language/rational thinking while activating the right non language thinking pattern. Often involves visual suggestions. B. Although traditional concepts of hypnosis address a person’s personality characteristics or susceptibility, others see this formulation as outdated. Instead, recent approaches (Ericksonian) see hypnosis as an interactional phenomena- a specific way of structuring conversation. 1. Both are actually in trance and both have control; focused attention 2. Can be therapeutic in that persons can resolve problems (since trance allows people to experience or consider events in a different way). a. approach needs empirical studies on effectiveness with various conditions and problems. b. is useful in pain management and relaxation (anxiety reduction) C. Meditation and Biofeedback are also trance like; some claim these methods are distinct from hypnosis, others see these methods as involving trance. IV. A. Drug Altered Consciousness Psychoactive Drugs are drugs that have a significant effect on behavior. Target of psychoactive drugs is the neurons of the CNS. Effect of drug depends on: 1. The drug or substance 2. Individual’s past experience 3. the person’s expectations about the drug 4. situation in which the drug is taken (Schachter’s studies) 13 B. 1. Categories of Drugs Stimulants: makes neurons across the cortex more excitable-stimulates the cortex. a.caffeine b.amphetamines: resemble specific neurotransmitters and stimulate cells, especially in the ANS. Some medical use- ADHD and sleep disorders. c. cocaine- immediate stimulation followed by depressing effect of CNS activity 2. Depressants: depress or reduce brain activity. Result in a calming effect and induce sleep. Long use is gradual deterioration of the CNS. Various brain disorder result from long time use of alcohol, including psychotic a. Narcotics- opium, heroin, morphine b. Hypnotics/Sedatives- the barbiturates, including Phenobarbital. Main effect on the RAS c. Tranquilizers d. Alcohol: people report alcohol as stimulant , it is actually a depressant on CNS activity. 3. Hallucinogenic: perception distorting drugs; stimulate the CNS LEARNING and CONDITIONING Learning: a relatively permanent change in behavior which is a result of past experience or practice. This definition reflects the strong behavioral stance in psychology. A psychologists using this perspective would claim behavior is learned and takes a strong nurture (vs. nature) stance. Several researched procedures that show the connection between stimulus & response. I. Classical Conditioning B. Pavlov’s Experiments: Ivan Pavlov was a Russian physiologist interested in digestion. While feeding dogs he noticed that the dogs produced saliva in the mouth before the food was placed in the mouth. So he decided to study this reaction. Set up the following procedure: 1. Rang a bell- dog heard but did not salivate 2. While ringing the bell, delivered food in the dog’s mouth- produced the salivary reflex. [Note: reflex is an automatic reaction- not learned] 3. Pair Sound + Food 4. Sound only (no food)- saliva produced. Dog has been conditioned to associate sound with the presence of food. Acquisition: the initial learning of the response; acquiring the response C. Definition of Terms: In the above Pavlovian experiement 1.Food is the UNCONDITIONED STIMULUS (UCS)- the stimulus that automatically and naturally produces the reflex or response. 2. The UNCONDITIOED RESPONSE (UCR) is the response produced by the UCS. UCS (food) ---------------------------- UCR (salivating) 14 3.Sound is the CONDITIONED STIMULUS (CS)- a neutral stimulus that eventually produces a similar response as the UCR 4. The CONDITIONED RESPONSE (CR) is the response produced by the CS. It is similar to but not identical to the UCR. unlearned UCS Food UCR Salivating CR CS Sound Learned 5. CLASSICAL CONDITIONING: procedure of pairing CS + UCS CS must come before the UCS. Optimal interval is ½ second. a.Backward Conditioning: when place UCS before CS. Appears conditioning is impossible with this procedure. b. Trace Conditioning: a lengthy interval between terminating the CS and UCS onset. Conditioning can occur which implies that the subject maintains a representation of the absent CS. c. Temporal Conditioning: time is the CS- the UCS is a regular time interval (e.g. 3 min). A CR begins to occur prior to the onset of the UCS 6.Review: Eye Blink D. a. UCS: Puff of air to eye lid- produce an eyeblink UCS (air puff) --------- UCR (eye blink) b. c. d. e. UCR: Eye blink CS: sound – does not produce a response Pair CS with UCS (CS + UCS) Present CS only, elicits an eye blink CS (sound) -------- CR (eye blink) f. CR: the eye blink to the CS (sound) Other Concepts from Classical Conditioning 1. Extinction: if you continue to present the CS without the UCS the CR will weaken or decrease in strength and eventually stop. 15 2. Reinforcement: Pavlov found that if occasionally follow the Cs by the UCS the CR would strengthen and continue indefinitely. Because the UCS maintains and strengthens the CR, it is a reinforcer- a stimulus that strengthens a response. Note that can redefine extinction as weakening of a response by removing the reinforcer. 3.Spontaneous Recovery: During extinction, the CR tends to reappear after a rest period. This phenomena is called spontaneous recovery. REVIEW OF ACQUISITION AND EXTINCTION Spontaneous Recovery Acquisition Trials UCS UCR CS + CR Extinction Trials CS + 0 CR 1. Most improvement is during early trials 2. There is a limit Rest More Trials To Extinction During Extinction 1. Behavior becomes more varied 2. Extinction is not permanent since CR can be reinstated by reinforcement 4. Stimulus Generalization: Pavlov found that if a dog was conditioned to a specific bell, it would also salivate to a different bell or sound (such as a buzzer). However, as the sound became more different than the original, the amount of salivating decreased. Stimulus generalization when trained to one stimulus and respond to similar stimuli. 5. Stimulus Discrimination: the counterpart to stimulus generalization- can learn to discriminate one stimulus from another. For example, the subject can learn to respond to a specific stimulus, such as a bell. Subject has been conditioned to a specific stimulus- can distinguish (discriminate) between two similar stimuli. Desensitization: a therapy procedure used to reduce fears and anxiety. Can be done live (in actual situation) or with visualization. For example, if person afraid of dogs can either slowly introduce a dog while person comfortable OR have the person imagine/picture dogs while relaxed. 16 II. Operant (or Instrumental) Conditioning: In this conditioning procedure, what happens to the subject depends on its response- what the subject does is instrumental in determining what happens; the response operates to bring about a consequence. Response ------- Consequence A. Difference between Classical and Operant Conditioning 1. Classical: subject is passive- waits for the CS and UCS 2. Operant: subject is active- does something to bring about a consequence. B. Operant Conditioning follows the same principles of classical: 1. Reinforcement: If a response is followed by a reinforcer, it will be strengthened or reinforced. A reinforcer is a consequence that strengthens the behavior- increases the chances that the behavior will be occur. a.A Skinner Box Experiment: a device used by BF Skinner to establish conditioning. 1)When in the box, rat makes a series of random movements- sniffs, scratches, washes, walks. 2)Eventually, the rat presses a lever and a pellet of food drops into a dish. May or may not notice thisoccurred. 3) Again, pushes the lever and notices food. 4) Begins to learn that pushing lever produces food. Response (pushing lever) ---- Reinforcement (food) Response is called the operant response since it operates to bring about reinforcement. b. Child’s Behavior: if a child’s behavior results in a desirable consequence, then it is likely that behavior will increase or strengthen. For example: temper tantrum results in soothing/attention will likely increase the frequency of temper tantrums. 2. Extinction: if the reinforcement is taken away then the behavior will extinguish. 3. Spontaneous Recovery: after a rest period, the behavior will reappear. 4. Generalization: behavior will generalize to other stimuli. For example, if a pigeon is conditioned to peck at a blue button to receive food, it will peck at other color. 5. Stimulus Discrimination: can learn to discriminate one stimulus from others; the pigeon will peck only at the blue one and not other differently colored buttons. C. Other Training Procedures: Thus far have focused on reward training- subject receives a reward for making a response. However, have situation in which the subject escapes or avoids a noxious stimulus. 1. Escape Training: subject learns to escape a noxious stimulus. a. Maze: part has an electric grid- subject must escape the noxious stimulus b. Skinner Box: press bar to turn off shock c. Turning off the Alarm Clock In escape training the reinforcement is turning off the noxious stimulus: Negative Reinforcement is the strengthening of a response by removing a noxious or aversive stimulus. 17 2. Avoidance Training: similar to escape except that a signal is given before the onset of the noxious or aversive stimulus. The subject can make the appropriate response to avoid the aversive stimulus. a. Maze: a light comes on 5 seconds before the shock begins. b. Skinner Box: Buzzer sounds 2 seconds before shock. c. Alarm Clock “chirps” 5 times before sounding alarm. D. Operant Conditioning in Real Life 1. Reinforcement of Speech: baby babbling; “I feel statements” 2. Classroom Behavioral Management 4. a. Reward when good; perform well b. Time-Out: extinction in that the person is timed out from possible reinforcements. Couple Interaction in which both behaviors are strengthened Fussing/Nagging -- Gets result desired: positive reinforcement Doing what’s wanted -- stops fussing/nagging: negative reinforcement Summary: when a subject responds to a stimulus which before did not elicit that response, learning has taken place. From the behaviorist’s view, all behavior is learned- “good” and ‘bad”. III. Principles of Reinforcement: A. Types of Reinforcement: Reinforcer is any stimulus (event, consequence) the strengthens a response. There are two type of Reinforcement: 1. Positive: behavior produces a positive result, a reward. 2. Negative: behavior removes a noxious or aversive stimulus. B. Delay of Reinforcement: sooner the reinforcer is given the greater its effect. C. Schedules of Reinforcement 1. Continuous: Reinforcement occurs every time the response occurs (100%). 2. Partial: reinforcement does not occur every time (< 100%). In real life, this is the rule, not the exception. Several partial reinforcement schedules: a.Fixed Ratio: reinforcement at a fixed event- every 2nd, 3rd, 4th…nth time. Example is piecemeal work: pay for making certain number of items. Result is a fast rate of responding. b. Variable Ratio: instead of getting reinforced every 2nd, 3rd, 4th…nth time, get reinforced on the average every 2nd, 3rd, 4th…nth time. Know a reinforcement will come but don’t know when. Since reinforcement is less predictable, response rate is not as high. Behavior established by variable ratio very resistant to extinction (e.g. gambling). c.Fixed Interval: reinforced for the first correct response after a fixed amount of time. So if the fixed interval is 30” the first correct response after 30” is reinforced (correct responses within the 30” interval are not reinforced.) Results in moderate rates with periods of spurts and of inactivity. d. Variable Interval: average the time interval; e.g. reinforced on average every 30”. Produces slow, steady rates. 18 3. Comparing Continuous with Partial: Behavior is learned quicker with continuous but behavior persists longer under partial (partial more resistant to extinction than continuous). D. “Superstitious” Behavior: if a random behavior occurs immediately prior to the reinforcement, then that behavior may also increase in strength. 1. If rat scratched ear before pressing bar that produced food, the rat may scratch ear again before pressing bar. 2. If pigeon moved head to right prior to pecking button that produced food, pigeon may do this head turning again- as if its part of getting reinforced. 3. May be the basis for human superstitious behaviors. E. Secondary Reinforcement: a stimulus that is paired with a primary reinforcer. Primary reinforcers are “natural” or unlearned- usually biological in that they satisfy a biological need (e.g. water, food, sex) or end discomfort (pain, excess heat or cold). 1. In Classical Conditioning CS (Bell) + UCS (food) --- UCR (salivating) CS (Bell) --------------------- CR (salivating) 2nd CS (light) + CS (Bell) -- CR (salivating) 2. In Operant Conditioning a. R (bar press) -- light (2nd) + food (primary) If have two groups and begin extinction, the second group will extinguish slower: Gr 1: bar press --- nothing Gr 2: bar press -- light + 0 c. Money: secondary reinforcement to get primary rewards. d. Parents and teachers learn to pair social with primary rewards when teaching children. 3. “Clockwork Orange” Movie: when shocked while watching aggressive films, character also is conditioned to the sound track of a film F. Shaping Behavior: reinforce closer and closer approximations to the desired behavior. IV. Punishment: a stimulus produced by a response that weakens the probability of response. Opposite of reinforcement in that punishment weakens a response. that A. Types of Punishment 1. Positive: the behavior results in an aversive stimulus being delivered. 2. Negative: the behavior results in a stimulus being removed; the taking away is punishing. [Note: extinction is when the response has no consequence (R - 0) 19 B. Issues with Punishment: punishment is effective BUT: 1. Timing: most effective immediately after the response. 2. Consistency: most effective if delivered every time (100%) 3. Intensity: severe can stop; mild/moderate only suppressesbehavior. C. Negative Side-Effects of Punishment 1. The punisher is feared, disliked, resented. Increase aggression toward punisher. 2. Avoids the situation in which punishment occurs. Attempt to escape; tend to avoid situation and may lie to avoid punishment. 3. Punishment informs what Not to do; does not show what to do. Therefore, the suggested way to modify behavior is to reinforce positive behaviors, extinguish negative, and use punishment to suppress and allow reinforcement of desired behavior. V. Cognitive Learning: higher level of learning. Cognitive learning refers to understanding, knowing, and anticipating. Extends to memory, thinking, and use of language. A. Latent Learning: Shows that learning can take place without a primary reward; learning takes place (but lays latent) until reinforcement takes place. Cognitive Map: this study suggests that the subjects have formed a “cognitive map” or internal representation. Driving: you may ride to Baltimore with a friend. Later, you could drive based on your riding experience and not having driven yourself. B. Observational Learning: learning that takes place by watching behavior (and its consequences) of others. [The other is called the model so sometimes learning by observation is called modeling.] Best used when the behavior is new to the learner and when it involves a complex set of behaviors. 1.Process of Observational Learning a. Being motivated to learn and carry out the behavior b. Attending to the model- perceiving and attending to the critical features of the behavior. c. Remembering the behavior that was observed d. Reproducing the behavior. If reinforced ,there is a greater likelihood the action will be repeated. 2.Social Learning Theory of Aggression: aggressive behavior is learned through observation. Issue of violence on TV. 3. Applications of Observational Learning a. Fear reduction- observe model managing a fearful situation [Note: observing another react to situation in a fearful way may result in a similar fear response in the observer.] b. Assertiveness Training c. Communication Training VI Summary: The Classical and Operant procedures define behavior in S-R terms while the cognitive-social learning approach places an emphasis on cognitive processes- thinking, internal representations, memory, and language. 20 Memory and Verbal Learning Instead of extending basic learning theory to human learning, some researchers restrict their interest to the learning of verbal material and its retention. I. Memory: the process by which we encode, store and retrieve information. A. The Process of Memory: converting perceived information into a form that it can be remembered. 1. Encoding: changing information so it can be placed in memory. Converting sensory data into a psychological format that can be mentally represented. a. Visual (iconic) b. Auditory (echoic/acoustic): sequence of sounds. Longer than visual c. Semantic: involves language- meaning 2. Storage: maintaining information over time 3. Retrieval: locating the stored information and bringing it into consciousness. B. Stages of Memory 1. Sensory (super short-term memory): encounter a stimulus and “hold” a memory trace in a sensory register. Very brief and decays quickly. About ½ second or less. 2. Short Term (working memory): if focus attention on a stimulus in the sensory register, tend to retain it in short term memory. Tends to fade if not repeated or rehearsed. Last 15-25 seconds a. Serial Position Effect: tendency to recall the 1st and last items of a series. b. Chunks: grouping information into one chunk- treat several pieces as one discrete piece. c. Displacement: new information displaces the old. While trying to remember a phone number, someone asks a question or phone rings. Rehearse Sense Data Sensory Memory Short Term Memory Attention No Attd Not Coded Forgotten Forgotten Coded Long Term Memory 3. Long term (LTM): relatively permanent- develop schemas to organize information; ways of representing the world. Rehearsal: leads to long term memory. Structured and organized. 21 a. Constructive Processes in Memory: remembrances change or are revised as new information is added. b. Verbal meaning/language use has influence on LTM. Experiment of subjects shown a movie of an auto accident. Then asked to estimate how fast the cars were going when the cars “smashed” vs. “hit”. A week later, subjects were asked if there was broken glass.“ Smashed group said yes; “hit group “no. (There was no broken glass) C. Kinds of Long-Term Memory: different kinds (modules) of information stored 1. Declarative: memory of factual information such as names, faces, dates a. Episodic (“I remember…”): memory of experienced events; takes place in the person’s presence. b. Semantic (“I know…”): general knowledge 2. Procedural (or skill): involves memory of how to do things; how to proceed with an action. Riding a bike, typing. II. Forgetting A. The Forgetting Curve: first plotted by Hermann Ebbinghaus who began studying learning and memory in the 1870s. In his studies, he discovered that most forgetting occurs immediately after memorization. Also, nonsense material forgotten more rapidly than meaningful material. B. Interference: forgetting is not just a function of time. What the learner does during the time may interfere with retention. Activity can interfere with memory. 1. Experiment where two groups learn a list of words: Group 1: learn list then active 8 hours Group 2; learn list then sleep. When retested, Group 1 remembered more words 2. Retroactive Inhibition/Interference: tendency for new learning to interfere with old. Groups 1 and 2 both learn a list of SS # and words. But Group 1 must learn a list of phone # and another list of words Group 1 Group 2 Learn A Learn A Learn B Rest Test on A Test on A Group 1 had more difficulty recalling or relearning the lists of A Practical Example: Study French Study Spanish French Test 3. Proactive Inhibition/Interference: tendency for old learning to interfere with learning new. Design similar to the above: Group 1 Group 2 Learn A Rest Learn B Learn B Test on B Test on B Practical Example: Study French Study Spanish Spanish Test 4. Negative Transfer of Learning- when something previously learned hinders learning or performance in a new situation (e.g. backing a trailer to right requires turning the wheel left). 22 5. Positive Transfer of Learning: there are times when prior learning can benefit later learning. What one learns in one situation helps in another situation. Learning driving a car helps learning to dive a truck, video game Learning tennis may help with badminton, ping-pong. To summarize- long term memory needs time to consolidate information. During this time of consolidation, other information or activity interferes with the consolidation. [Metaphor of wet concrete: information written in wet concrete- if set written to last; if scribbled over (interfered) than can be lost.] III. Overcoming Forgetting A. B. C. D. E. Recite: repeat what you have learned Over-learning: after you have learned the material go over it again Spaced (vs. Mass) Learning: spread out the time periods. Four 15” periods produce more learning than one 1 hour period. Part vs. Whole Learning: depends on the nature of the material. If short and wellorganized, whole may be better. Part is likely better for long, complex material Active (vs. Passive learning): more active approach leads to better results. Group 1: Group 2: Group 3: Group 4: all reading ¾ reading, ¼ reciting ½ reading, ½ reciting ¼ reading, ¾ reciting Groups that recite the most retain the most. Also, if one group reads to self and another reads out loud, the group that read out loud has better recall. Thought, Language and Higher Mental Processes Challenges the strict behaviorist’s perspective since thought processes cannot be observed. Instead, thinking is inferred from observations. I.Thinking: the mental manipulation and combination of images, concepts, words, It is the basis of problem-solving and creativity. and symbols. A. Images: forming mental pictures (visual) or other sensory images (sound, kinesthetic, smell, taste). May have a preferred way of representing- visual, auditory, kinesthetic. B. Concepts: a word or idea that represents a class of objects. Categorizations of objects that share common properties. For example, cards can be sorted according to number or color. II. Problem-Solving: involves thinking and reasoning. 23 A. Seeing the problem and defining it B. Preparation: Understanding the kind of problem and organizing the problem. Obtaining the information and organizing the information available. Develop assumptions. May not realize making faulty assumption or oversimplifying. Way approaching the problem may in itself be the problem. C. Generating Solutions 1. Trial-and error 2. Insight: the “ah-ha” experience or sudden awareness D. Evaluating and testing the solution III. Language: language involves concepts and symbols whioch stand for objects and ideas. Lguage is structured and some say language structures experience since we tend to make sense of the world with language. A. Framing of Reality: how the person “frames” reality with words, concepts and labels will determine the person’s behavior, including emotions. B.Language influences what people attend to and what they see. Language helps determine how the person makes sense of the world. Intelligence Like thinking, intelligence cannot be directly observed. Yet we are certain it exists and that there are different levels or amounts. The concept is difficult to define and its definition will depend on how it is measured. I. Definition: the capacity to understand the world and the resourcefulness to deal with its challenges. A. Permits us to adapt to current and changing conditions B. The definition implies several factors: 1. General Factor (g- factor): 2. Special factors (s-factors) or primary mental abilities. C. Multiple Intelligence: Different Kinds of Intelligence? Kind of Intelligence General Factor Fluid and Crystallized Multiple Information processing Practical Emotional II. Characteristics Underlies all intelligence; Traditional IQ tests assume a g-factor Fluid: reasoning, memory, ability to process information Crystallized: information, skills, and thinking strategies gain via experience Different forms of intelligence that work together. Different degrees of each Ways people store and use information to solve problems. Ability to solve every day problems (vs. solving academic type problems) Inter and intra personal understanding; allows appropriate responding to others Measuring Intelligence: the Development of Intelligence Testing A. Alfred Binet: asked by the French Education Ministry to develop a way of distinguishing slow students from capable student. At first he used various measures, such as memory tests and head size, but these measures failed their purpose. 24 1. Binet’s definition of intelligence was the faculty of “ …judgment, otherwise called good sense, practical sense; … the faculty to adapting to circumstances.” The essential activities of intelligence were to judge well, reason well, and to comprehend well. 2. In 1905 tests were given that were considered successful. Continued to develop tests and in 1908 developed a scale that arranged and grouped items by “normal age”- later called mental age. 3. Mental Age (MA): Binet began averaging performance of each age group (for example, for 5, 6, 7, and 8 years of age). An item would be considered if failed by the earlier age group (for example 6 yrs.) but passed by 50%-75% of the next age (7 yr.olds). a. If a child can answer questions usually answered by the average 9 year old, the child has a mental age of 9 years. b. If an 8 year old answers questions typical of an 9 year old, the 8 year old would be above average. c.If an 11 year old answered only questions typical of 9 year olds, than the 11 year old id below average. 4. Intelligence Quotient (IQ): introduced by Stern who came up with: IQ= MA/CA * 100 a.If the CA=MA than IQ= 100. For example if the 11 year old child answers questions typically answered by 11 year olds then: 11 (MA)/11 (CA) * 100= 100 IQ b. If a child is 10 years old and scores like most 12 years old than the child’s IQ= 120 (12/10 * 100= 120). c.If the 10 year old only answers question typical of 8 year olds, than the mental age is 8 and the IQ is 80 (8/10 * 100= 80). d. The IQ score allows measure of relative brightness. For example, a 4 year old and an 8 year old answer items typically answered by the 6 year old group. Both the 4 and 8 year old have a mental age of 6 years but the IQs differ- 150 IQ for the 4 year old, 75 IQ for the 8 year old. 5. The Stanford-Binet: the test developed by Binet was developed in the US on children near Stanford, CA. First version in 1917 with several revisions, most recent in 2003. Although it provided only one score, the most recent version split up scores into verbal and performance as well as a full scale score. B. David Wechsler: the Binet tests only applied to child populations, in part because the mental age could only be determined to age 16-17. Therefore, Wechsler developed a test for adults- the Wechsler Adult Intelligence Scale (WAIS). Later, he developed the Wechsler Intelligence Scale for Children (WISC). Several revisions of both the WAIS and WISC 1. Wechsler’s definition of intelligence was global: “the global capacity of the individual to act purposely, to think rationally, and to deal effectively with the environment.” 2. Wechsler did not use the concept of MA, but did retained IQ. Also, his items were both verbal and non-verbal (performance) so would have a verbal IQ, performance IQ and a Full-Scale IQ. 25 Comparing the different subtest scores can provide evidence of learning difficulties and neurological problems C. Further Developments 1.Group Intelligence Tests: the Binet and Wechsler tests are administered individually. In order to test large populations, such as school children, group tests were developed. (Actually, the first attempt was by the military to screen recruits during World War I.) 2. Other Academic and Educational Tests a. Aptitude: designed to predict a person’s ability in a specific area. The SAT and ACT is an aptitude test in that it attempts to predict the person’s ability to succeed in college. b. Achievement: designed to determine a person’s level of knowledge in a specific areas 3. Issues of Reliability and Validity: numerous tests have been developed to measure intelligence, aptitude, and achievement. And most evidence: a. Reliability: similar scores are obtained on different occasions. Also, reliability increases as age increases- the young age range (2-5 years) has more variance than do older groups. b. Validity: the test appears to be measuring what it intends to measure. Scores also correlate with other behavioral or performance measures, such as academic success. III. Distribution of Scores and Classification of Intellectual Level: When evaluating a random sample, the distribution of IQ scores approximates a normal or bellshaped curve with most scores close to the average and few at the extremes. The average IQ score for the sample is defined as 100; the statistical procedure that calculates standard deviation sets the range. A. The Classification of Intelligence Scores: based on the test’s average (mean) and standard deviation. The above Wechsler classification is based on the standard deviation of 15. 1. The Average Range: Between 85-115 IQ. Approx. 68% of population falls in this range. 2. Bright-Average Range: between 115-130. 3. Superior/Gifted Range: above 130 4. Below Average Range: between 70- 85 IQ. 5. Mental Retardation Range: below 70 IQ score. However, note that IQ is not the only component; social adaptability must also be considered. B. Relation of IQ Scores with Other Variables 1. Sex: no significant difference between men and women. However, women tend to do better on items requiring verbal ability, men on items requiring arithmetic reasoning or visualization of spatial relationships. Difference likely a result of social conditioning. 2. Age: Difficult to determine since it depends on how sample the population (cross sectional vs. longitudinal studies). 26 a. Cross Sectional Studies (comparing performance of different age groups) shows some minimal decline in some specific areas-especially items that are scored with speed/time). b. Longitudinal studies do not show a decline. 3. Grades: strong correlation between IQ and grades. 4. Race/Ethnicity: comparison of ethic groups contaminated by class and other social factors. What differences that do occur appear to be a result of racism rather than of race. Also, the issue of cultural sensitivity- tests still tend to reflect White middle class standards despite effort to minimize these effects. In many studies that compare IQ scores, whites tend to score higher but larger overlap. Studies suggest that environmental factors are behind the differences- class, culture, language, motivation, quality of nutrition. a. Socio-Economic Class: correlation between class and IQ, the high the socio-economic class the higher the IQ. b. Urban populations score higher than rural populations c. Northern populations tend to score higher than Southern d. When children placed in an enriched environment, IQ scores tend to go up. IV. Genetics: The Heredity-Environment Issue A. Twin Studies: suggests a heredity influence Identical twins IQs highly correlate (.87-.92) Fraternal twins IQs moderately correlate (.50-.70) which is similar to siblings reared together. B. Differing Environments: suggests contribution of environment. Correlation is lower when twins are reared apart with the higher score for the twin raised in the better environment African-American Children adopted by White parents at 6 months; mother average IQ approx 85. (Fathers’ IQ not known but evidence suggests similar to mothers’.) When tested at age 13 years, children’s’ IQ approx 106. But other studies show child’s IQ correlates more with natural parents rather than adoptive. In cross-cultural studies, the economically disadvantaged group typically shows lower IQ scores. To summarize the Heredity-Environmental Debate, it appears that genetics may set to limit or potential but environment determines how much of the potential is reached. Tests only measure current intellectual functioning level and not capacity or potential. V. Mental Retardation: defined as an IQ score below 70 AND impairment in social adaptability (for example, level of community skills, safe-care, ability to live independently). A. Classification of Mental Retardation 1. Mild: IQ score 55-69. Typically can live independently, hold jobs, and raise a family. Approx 90% of people with MR fall in this range. Achieve a 5th -7th grade level. 27 2. Moderate: IQ score 40-54. Can hold simple jobs, such as in a sheltered employment setting and have some difficulty with independent living. Basic language skills and routine self-help. Therefore, typically need some supervision to manage daily living situations. 3. Severe and Profound: IQ below 40. significant impairment and often require institutional care. B. Causes (Etiology) of MR 1.Genetic: due to genetic abnormalities. No single gene that determines intelligence so MR results from combined effect of many genes and chromosomes. With the exception of Down’s syndrome, MR is typically severe when genetically based. 2. Metabolic: result of faulty enzyme system so metabolism is not performed correctly. PKU does not allow milk products to be metabolized properly- poisons the infant and results in MR. 3. Prenatal: damage caused before birth- such as alcohol or drug use. 4. Natal: events that occur during birth such as head injury or asphyxia. 5. Familial: no known biological cause exists but a history of limited intellectual functioning in the family. Difficult to determine if it is a result of genetic factors, poor nutrition, poverty, or impoverished environment. a. Majority of MR falls in this heading b.Enriched educational settings improve performance on IQ tests VI. The Intellectually Gifted: IQ scores greater than 130. Usually well adjusted socially and above average in height, weight, and physical ability. VII. Learning Disabled: people evidence learning differences and some people have problems in learning specific subject or areas that require specific abilities such as verbal reading or numerical reasoning. Not associated with IQ- in fact to qualify for LD service, learning problem cannot be due to MR. 28