Nervous Case Study 8*

“I Can See Clearly Now …”

 

Sandy is a right-handed man in his mid-twenties. During a mugging, he suffered a gunshot wound to the head. The bullet entered the back of his head, but did not kill him. After being transported to the ER, doctors assessed his condition. They found the bullet’s entry wound in his left occipital area, and a CT scan was ordered. The scan showed that the bullet had traveled horizontally through both occipital lobes, and that there were several small hemorrhagic foci and air bubbles in his right parieto-occipital region. What worried the doctors most was the presence of small metallic fragments in his parietal lobes, particularly on the right side.

 

Doctors operated immediately to remove the bone and metal fragments from Sandy’s right parietal lobe. His surgical recovery was without complication. Following physical therapy, he regained the majority of his movement and seemed to be relatively “normal” with one exception—his vision was impaired. Although he could still “see,” he had a variety of problems recognizing objects.

 

About 18 months later, Sandy was still having vision troubles and was admitted for a full workup. Standard neurological testing did not yield anything diagnostically relevant with regard to his visual troubles, and so Sandy was referred for a neuropsychological evaluation. Among other things, his neuropsychologist administered intelligence tests as well as a series of tests intended to evaluate Sandy’s visual perceptions.

 

In the initial interview with his evaluator, Sandy described some of his issues. One of his major complaints was that he didn’t seem to be able to “see the entire picture.” He claimed that he could see objects, but for some reason was unable to take a larger view. He over focused on one or two particular details of an object and couldn’t recognize the whole thing. Sandy also told the evaluator that he couldn’t “see” more than one object at a time; he was quoted as saying “… when two people are walking together I can’t see both of them at once.”

 

After an extensive battery of testing, the evaluator compiled Sandy’s results. Here are some of them:

 

Test

Administration

Sandy’s Performance

Wechsler Adult Intelligence Scale-Revised (WAIS-R)

The WAIS is a series of subtests intended to assess verbal abilities (such as Information, Comprehension, Arithmetic, etc.) and non-verbal abilities (such as Picture Completion, Picture Arrangement).

Normal on verbal portions, but unable to complete nonverbal portions; he was unable to complete any of the pictures or arrange them in the correct order.

Rey-Osterreith Complex Figure Test

Requires a patient to copy a complex figure while it is still in front of them, and then to reproduce it from memory after a delay.

Unable to copy any of the figures, either immediately or from memory.

 

 

                 

                                   

Along with the standardized neuropsychological tests, Sandy was asked to draw simple figures like a circle or a picture of a cat. Unfortunately, he was unable to imagine or describe these from memory.

Macintosh HD:Users:bernie:Desktop:figure1.jpg

 

Luckily, Sandy did not show any signs of significant motor problems (such as paresis, or weakness, in his limbs). However, when asked to perform complex motions, such as the sequence required to successfully complete a phone call from beginning to end, he failed to do so correctly.

 

Questions

 

1. Why is there electrical activity in the brain? Describe how nerve impulses are transmitted from neuron to neuron.

2. What is myelin? What is its function?  Explain.

3.Compare and contrast the structure and functions of the Central Nervous System and the Peripheral Nervous System.

4.What condition or conditions (there may be more than one possibility) are being described in this case?

5.What brain area or area(s) may be involved? Be sure to consider which visual stream is involved. Is there a specific hemisphere that is affected? How do you know?

6.How should these brain areas function normally? What could be causing this dysfunction?

7.What do the assessments and their results tell you about this person’s abilities and condition?

 

Remember to document your sources!

 

*Adapted from National Center for Case Study Teaching,

University of Buffalo, State University of New York

by Antoinette Miller