lateralization of function function or behavior found in only one cerebral hemisphere why might there be lateralization? what are its advantages and disadvantages?

lateralized behaviors left hemisphere –analytical abilities –quantitative skills –language right hemisphere –music –spatial abilities –artistic abilities –emotions –facial recognition

Language most well studied lateralized behavior –95% of right handed have speech on left –70% of left handed have speech on left aphasia – language deficit that cannot be attributed to motor, motivational, sensory or other explanations

Broca’s Aphasia characterized by broken halted speech, absence of prosody comprehension – fairly good; ability to read – fairly good

Wernicke’s aphasia fluid aphasia, deficits appear to be in comprehension; words are nonsensical comprehension – poor reading ability - poor

Wada test injection of sodium amytal or sodium amobarbital – anesthetic used to determine hemisphere important for speech

Another way to study lateralized behaviors is via “split brain” patients split brain surgery

consequences of “split brain” initially – –“Breakdown of the Bicameral Mind” Julian Jaynes –subsequently – only can really tell by experimental manipulations in the lab

Emotions emotional facial expressions – evolutionary explanation

Emotions emotional facial expressions – evolutionary explanation role of right hemisphere –recognition of emotion –display of emotions –chimera brain damaged humans

brain regions involved in emotion limbic system- –components of limbic system- includes hypothalamus, hippocampus, amygdala, olfactory bulbs, septum sits within the temporal lobe –temporal lobe epilepsy

Kluver Bucy Syndrome Kluver Bucy syndrome –associated with temporal lobe damage characteristics:

Kluver Bucy Syndrome Kluver Bucy syndrome –associated with temporal lobe damage characteristics: 1. extraordinary tameness

Kluver Bucy Syndrome Kluver Bucy syndrome –associated with temporal lobe damage characteristics: 1. extraordinary tameness 2. lack of fear

Kluver Bucy Syndrome Kluver Bucy syndrome –associated with temporal lobe damage characteristics: 1. extraordinary tameness 2. lack of fear 3. put anything in the mouth

Kluver Bucy Syndrome Kluver Bucy syndrome –associated with temporal lobe damage characteristics: 1. extraordinary tameness 2. lack of fear 3. put anything in the mouth 4. mount anything