# Brain Lateralization ![[corpus-callosum.png]] - Epilepsy - _Petit mal seizure_ - electrical activity burst freezes one's action for a while - _Grand mal seizure_ - electrical surges in one hemisphere passes to another, and then back and forth to form a ==feedback loop==, literally short circuits the brain. [[brain-structure#Parietal Lobe|Motor cortex]] is stimulated randomly, hence convulsions. ## Contra-Lateralization ![[split-brain-experiment.png]] - What do you see? (Left brain answers) Ring. But key would be grabbed (right brain acts). - Presenting a sexually evoking picture to the right brain -> patients blush -> "Why do you blush?" -> (Left brain answers) "I just thought of an off-color joke." - Looks like left brain notices the blush, and ==made a theory around it== to explain. (The activation-synthesis hypothesis of [[dream]]?) --- - One eye for danger, the other for food/sexual objects. ## Left-Handedness - 12% in women, 8% in men. - Right brain for big picture, left for details. - Left-handers - Pay more attention to the left - Are less lateralized - Have denser corpus callosum - 6 months lower life expectancy - Genetic hypothesis - Two genes controlling handedness. - Handedness gene, and change gene (identical twins can have different handedness)