Class Notes (1,100,000)
CA (620,000)
UTSC (30,000)
Psychology (8,000)
PSYB65H3 (500)
Ted Petit (300)
Lecture

lecture notes 09 - brain damage(1)


Department
Psychology
Course Code
PSYB65H3
Professor
Ted Petit

This preview shows half of the first page. to view the full 2 pages of the document.
historical data about brain damage influence
adult--
(1) bullet damage in LH
-100% had aphasic symptoms
-30% showed SOME degree of recovery among left-handed or ambidextrous individual
s
-least recovery among right-handed people
(2) bullet damage in RH
-few language problems, relatively rare leading to aphasia
-those who showed aphasia were left-handed or ambidextrous people, right-handed
people had NO aphasic symptoms
-MOST patients showed recovery from language problems
*seem like: language center is located at LH for right-handed people
language is bileterally represented for left-handed and ambidextr
ous
children (under age 5)--
-damage on either side had equal probability of getting aphasic symptoms
-100% showed recovery
*seem like: language ability on both sides in children, not clearly leteralized
yet
functions will move to LH over development on right-handed people
(there will no language function among RH)
plasticity - each side is capable for the other, when early damag
e to one side, the other is easy to take over its function
people born without corpus callosum--
-language ability is locolized on both sides in adult
*seem like: when we are born, both sides are capable for language
as we matured, LH appears to dominant for language of individuals
(shift to the left during development)
LH seems to be better for language and automatically sepresses RH
; if two sides are not connected, some language will stay in RH
LANGUAGE & LEFT HEMISPHERE
planum temporale - primary language area in temporal lobe
-at LH side: 1/3 larger, more convoluted, heavier
(suggest that complex left side is more equiped for handling language)
-even in other species, LH is larger than right
(evolutionary predisposition of genes on vocal communicating between organisms)
-between week 10 and week 31 of gestation, humans already show larger anatomical
structures in LH
brain research on 'normal' people--
-using sodium amytal, inject from neck to the brain, asking subjects to count nu
mbers
-result: language ability in LH on right-handed, both sides on left-handed and a
mbidextrous (same as research on brain damage people)
-another research shows LH deals with verbal info 20ms faster than RH (appears t
hat RH takes 20ms to transmit infos to LH since RH can't solve by itself)
split brain syndrome--
-cut the corpus callosum to avoid seizure of whole body (grand mal epilepsy)
-patients appear normal in daily life but not normal during behavioural tests
-famous research:
*present infos to non-verbal hemisphere (RH) in right-handed split brain patient
s
(1) when projecting an object visually
-patient cannot describe the object verbally (because LH get no info about objec
t)
-cannot pick up object correctly using right hand (controled by LH)
-CAN pick up correct object using LEFT hand (controled by RH which has infos abo
ut object)
(2) when projecting an object verbally (words)
You're Reading a Preview

Unlock to view full version