Class Notes (806,815)
Canada (492,451)
Psychology (7,610)
PSYB65H3 (519)
Ted Petit (310)
Lecture 9

Lecture 9.docx

7 Pages
Unlock Document

University of Toronto Scarborough
Ted Petit

Lecture 9 Leaving pharmacological behind Turning attention to lobes and how the lobes function Globalization in terms of specializations Much greater picture of right brain vs. left brain Much of what we will look it focuses upon language Historical Level: How do we start to get information one left and right brain having different functioning Adults Kids Historical Overview: Adults Early awareness of right and left - observations during periods of war Bullet wounds to the head Right hemisphere and left hemisphere damage would have different effect Right hemisphere damage in adults: Most patients showed few aphasic symptoms Rarely led to a complete aphasia Those people who did show an aphasic symptom were always left handed or ambidextrous Right handed people did not show any aphasic symptoms with right hemisphere damage Right handed individuals - only time they had a problem was if the damage had been on the left. Language is on the left Left handed: lose language from either side. Not really all that severe Recovery: L handed people showed excellent recovery from the damage L handed people would probably have language on both sides L handed people: either side will damage you, but you can recover R handed people: cannot recover as if the left handed side is damaged R handed people: the right hemisphere damaged, then language is fine Left hemisphere damage in adults: 100% of patients showed some aphasic symptoms (Problems in speech and language) Aphasia: would imply that they have no usage of language We do not usually use it that way We are using the word in an incorrect scientific way Mild aphasia Approximately 30%showed recovery All left handed or ambidextrous individuals: Ambidextrous may in fact just be left handed, but society has forced them to use the right hand Least amount of recovery was in right handed individuals These were the first indications that there was specializations in language Also indicated that language was predominantly in left hemisphere for right handed individuals Contralateral So if left handed or ambidextrous, then you would lose language but you would be able to learn it back again Some of the language is on the left but some of it is on the right Right is also capable of language in left handed people Left handed = left handed and ambidextrous Children Less than 5 years old Damage to either hemisphere will have an equal probability of producing aphasic symptoms In a child: language is on both sides Developing: language will be on both sides 100% of children who suffer brain damage would show recovery Many ways they are like left handed people Damage on either side can disrupt language but they will be able to recover Adult: Lateralized Child: Not so lateralized. Still pretty general Ambidextrous: Telescope: which eye they use Football: which arm you throw with Very hard to determine which you fall into If you use both hands for writing, you are probably ambidextrous 2-3 year old up to a 10 year old their brain does become more lateralized 5 or so: more lateralized Language moves more dominantly to the left Lateralization occurs primarily in right handed individuals Less lateralization in left handed individuals Less lateralization and more plasticity, can actually remove half of the brain and the child can recover and can actually do quite well Left with damage: lots of scar tissue - more likely to get epilepsy Better to go in and take it out Other hemisphere will take over and do the right work Acollosal People Born without a corpus callosum Families had a high percentage born without any corpus callosum - used to be the case in Quebec In adults: language exist on both sides of the brain No deficit in language - just like left handed individuals Children that have had early extensive brain damage Language is almost always on the opposite side of the brain For the most part, things are pretty good Shift: language will shift to the left only if you have a corpus callosum Left hemisphere is better at language Actively suppresses the right hemisphere as the individual matures Either side could do it, but left is just better at it If left cannot talk to right (no corpus) this lateralization does not happen There may be a better explanation, but this seems the most logical method put forth All of this of course has been shown in right handed individuals Some research is there that left handed people have had brain damage - not inhibiting the right anymore by the left Anatomical Research Again right handed individuals Why is it the left so much better? Planum Temporale - Primary language area in the temporal lobe In the left hemisphere: this PT is larger and is more convoluted It is heavier than the exact same area in the right hemisphere by a third Suggests why the left hemisphere is better Same across right handed and left handed and ambidextrous, and even different species Question: Is the usage why the PT is bigger (PT size is the result) OR has it always been like that Is it use or is it genetic? Research into great apes found that the PT size difference is also present in them Also true in other animals that use vocalization as a form of communication - e.g. birds Even there - birdsong will be located on the left Vocal communication is a primitive genetic phenomenon that has been preserved We have cellphones, books, - most evolved language Vocal communication - Left hemisphere will be larger and language located here Suggests a genetic basis. Anatomical component Newborns and left-handed individuals - PT is still larger in the left temporal lobe Still not a great explanation as to why left handers do NOT switch over 10th-31st week of gestation - already a PT size difference. Before any exposure to language Certain parts of the genome have been preserved very well Sodium Amytal Another approach that confirmed what we already know If a patient is up for surgery for epilepsy, we want to know where the epileptic focus is Usually at the hippocampus Very frequently at the hippocampus - just beneath the speech area Need to find out where the focus is Sodium Amytal is injected into the carotid artery Right or left Sit on hospital bed, hold up arms Anesthetize right
More Less

Related notes for PSYB65H3

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.