Download Neurological assessment – part two

NEUROLOGICAL ASSESSMENT – PART TWO
Name of examiner: ______________________________________ Name of “patient”: _______________________________ Pts. Gender (M) (F)
More reflex assessment!
Today we will perform the patellar reflex assessment again with a slight variation. We will also look at the photopupil reflex.
Test
Observations
Patellar.
A. With the patient's legs dangling (if possible), place your
hand on one thigh and strike the leg just below the kneecap;
the leg should extend at the knee.
B. Now divert your patient’s attention by having him interlock
the fingers of both hands and having him pull his hands
against each other while you strike the patellar tendon again.
Is the response the same as before? If not, how do you
explain the difference?
Photopupil.
A. Have the patient sit with eyes closed, facing a darkened
part of the room for 1-2 minutes. When the patient opens his
eyes, note any change in pupil size.
B. While the patient is looking into the darkened area, shine a
penlight about 3 feet away from his eyes (but not directly into
them). Note any change in pupil size.
C.
While the patient is looking into the darkened area,
observe the patient’s right eye. While observing the right eye,
shine a penlight into the left eye. Repeat this on the other
side. What happens?
While part of the students do the above experiments, other students will perform the following experiment:
Reaction time:
The nervous system controls and coordinates our reactions to thousands of stimuli each day. Some of these reactions are reflexes, but many are
voluntary reactions, or responses that are consciously initiated. Reaction time is the time interval from the instant of stimulation to the instant of a
voluntary response. All responses result from the formation of impulses by stimulation and the transmission of these impulses along neurons to effectors
that bring about the response.
In reflexes, impulses flow over predetermined “automated” neural pathways involving very few neurons, and they do not require processing by the
cerebral cortex. In contrast, voluntary reactions involve a greater number of neurons and synapses, and require processing of impulses by the cerebral
cortex. Therefore, reflexes have much shorter response times than voluntary reactions.
The reaction time for a voluntary response is the sum of the times required for:
1. A receptor to form impulses in response to a stimulus
2. Transmission of impulses to an integration center of the cerebral cortex
3. Processing the impulses in the integration center
4. Transmission of impulses to effectors
5. Response by the effectors.
So…this all happens very quickly!
Here’s how to do the reaction time experiment:
One partner will be the “subject” and the other, the “experimenter.” You will use a ruler.
1. The subject sits on a chair with the experimenter standing facing the subject.
2. The experimenter holds the ruler with the higher numbers at the top between his or her thumb and forefinger near the subject’s eye level.
3. The subject places the thumb and forefinger of his or her dominant hand about an inch apart and on each side of the “0” at the lower end of
the ruler. The subject’s attention is focused on the ruler at the thumb line.
4. When the subject says he or she is ready, the experimenter, within 10 seconds, releases the ruler. The subject, seeing the falling ruler,
catches it between the thumb and the forefinger as quickly as possible.
5. The reaction time is read in centimeters at the upper edge of the thumb and recorded. To convert centimeters to milliseconds, use the chart
located below this data recording section.
6. This test is repeated 5 times and the average reaction time is calculated. If any reaction time is grossly different, discard it, and repeat the test
to obtain 5 results that are fairly consistent.
Do you think practice and learning will decrease your reaction time? Test this theory. Repeat the reaction time test 20 times without recording the
reaction time. Then repeat the test 5 times and record your reaction results.
Reaction times before practice:
In centimeters:
Reaction times after practice:
In milliseconds:
In centimeters:
In milliseconds:
Average reaction time in milliseconds:
Before practice:
After practice:
Converting centimeters to milliseconds:
Distance in
centimeters:
5
10
15
20
25
30
How many milliseconds are in one second??? Do you know???
Time in milliseconds:
100
140
180
200
230
250