Class Discussion Information — Week 7

Facial Recognition

The Fusiform Face Area stretches across the temporal and occipital lobes of the cerebral cortex (see figure). When it is damaged, especially in the right hemisphere, people often suffer from prosopagnosia—an inability to recognize faces. These people can see all the parts of the face, they just are unable to put them together to form a whole.

Fusiform Face Area in the Temporal and Occipital Lobes of the Cortex

Language Areas in the Cerebral Cortex

Broca’s Area

Broca’s Area is most important for the production of language (whether it involves speaking or writing). When Broca’s Area is damaged, people suffer from Broca’s Aphasia, which typically includes difficulties with spontaneous speech, repeating words spoken by another, and comprehending “grammatical words” (the words that join nouns and verbs together to make a grammatically correct sentence). The man in the following video has an atypical case of Broca’s Aphasia. He can engage in spontaneous speech and has no trouble with repetition; but he is unable to comprehend grammatical words.

 

Wernicke’s Area

Wenicke’s Area is important for language comprehension (whether spoken or written). When Wernicke’s Area is damaged, people suffer from Wernicke’s Aphasia, which typically includes difficulties with comprehending nouns and verbs, naming objects (anomia), and even repeating the same word spoken by others. In fact, they often use neologisms–words that they make up–when they try to name objects or repeat words spoken by others (see the video at the end of Section 3-9 for examples). The man in the following video shows all of these problems.

 

The Frontal Lobes & Working Memory

Parts of the frontal lobes are very important for retaining information (i.e., mental representations of the world) at the conscious level for a short period of time (which we referred to in class as short-term memory) and using this information (processing it) to accomplish goals/tasks. This is referred to as working memory. For example, you would be using your working memory when calculating the following in your head: 2 x 6 x 4 is equal to what number? In this case, you would need to retain mental representations of the three numbers at the conscious level for a short period of time while you processed them (multiplied them) to come up with the correct answer: 2 x 6 x 4 = 48. If certain parts of the frontal lobes are damaged, working memory may be affected, as was the case with the man featured in the following video:

Study Questions for this video:

1. Bill’s wife stated that he was “still very intelligent.” What did she say was his major problem?
2. What did Bill’s former law colleague say was the major reason why Bill could no longer practice law?
3. Family and friends notice major changes in the functioning of “frontal-lobe patients.” Why is it so difficult for strangers to realize that frontal-lobe patients have severe problems in everyday functioning?
4. Why did the neuropsychologist use tinker toys to test the patient’s frontal-lobe functioning?
5. According to the brain researcher, Daniel Weinberger, what do the frontal lobes do?
6. According to the brain researcher, Patricia Goldmann-Rakic, what do the frontal lobes do?
7. What did the experiments with the galago and rhesus monkeys show? (Please relate this to the concept of “mental representation” in Section 3-11).
8. What did the narrator mean when he stated that the baby’s brain functioned more like that of a galago monkey than a rhesus monkey?

Capgras’ Delusion & Disconnection Syndromes

The different parts of the brain are highly interconnected. When connections are broken between brain areas, unusual behaviors and cognitions may develop. Capgras’ Delusion is one example of this: it seems to be due, in part, to a disconnection between areas for visual recognition of objects in the temporal cortex (perhaps especially the fusiform face area) and areas for emotional responses to these objects in the limbic system (perhaps the amygdala in David’s case). The hypothesis tested in this video clip is that the disconnection between the two areas causes people to develop the delusional belief that close friends, family members, etc., have been replaced by impostors who look exactly like them.

Source: BBC Documentary: Phantoms In The Brain

Thursday’s Test

Please bring a green Scantron form. And before you come to the test on Thursday, watch the video below. It will put you in the proper frame of mind (i.e., it’s only one test in a lifetime of evaluations, so put it in the proper perspective):

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