Split Brain
Research
Learning about
right brain/left brain
differences
Function of the corpus
callosum
• Seizure – period of
excessive neural activity in brain or
brain area
• Epilepsy - Recurring seizures; about 1-2 in 100
people has epilepsy; ccurs in many
forms
• May be inherited or or may
follow some injury to the brain
• In the latter case, seizures
usually begin at the injured spot (the “focus”) and it is called “focal or partial seizure”. Because the brain is so conductive, partial
seizures may spread
Visual Fields
• Each half of your brain sees
the opposite half of your visual world
• Similarly, each half of the
brain senses and moves the opposite half of the body.
Roger Sperry –
Testing of
Split Brain Patients
Left Brain Sees a Ball
• “I see a baseball”
Right Brain Sees a
Hammer
•
“I
see nothing”
•
But
left hand can select the hammer, indicating hammer was perceived but couldn’t
be verbally identified by right hemisphere.
• This is evidence for “lateralization
of function” – that is, one side of the brain having different
functions/abilities than the other side.
Left: Language, mathematics, analytical/detail
Right: Visual/spatial processing, interpreting nonverbal
sounds, voice intonation, music, recognizing and expressing emotion.
Left Hemisphere
Subjective Interpreter
• Gazzaniga proposes the LH
provides our inner voice narrative interpretation as we try to make sense of
the world, the verbal reconstruction of our memories.
Aphasia: language
problems due to brain damage
• The greater the damage in
the vicinity of Broca’s area, the greater the difficulty producing speech:
“Broca’s aphasia”
– Both spoken & signed;
affects writing & gesturing too
– Affects the use &
understanding of grammatical words, endings, & meaning conveyed by word
order
– Results in “telegraphic
speech” (nouns & verbs)
• Damage to Wernicke’s area
disrupts memory of words & speech comprehension/comprehensibility:
“Wernicke’s aphasia” Can talk but not make sense.