PSY318H5 Study Guide - Spatial Memory, Hemispherectomy, Epigenetics
Document Summary
Damage to the posterior part of the left temporal lobe. Little evidence of differences in anatomy in right and left-handers. Majority of left-handers have left lateralized speech (70%) Larger incidence of left-handedness among children with neurological disorders (dominant hemisphere) Little known about cerebral organization of those with right hemisphere speech. Proposes left hand is better for holding a shield or holding a baby. Right-handedness due to enhanced maturation and greater development of the left hemisphere. Most species have a left-sided developmental advantage/bias that is not genetically encoded. Different levels of testosterone influence cerebral asymmetry (geschwind-galaburda theory) Dominant gene rs+ for speech in the left hemisphere, which gives motor advantage to right hand. Recessive gene rs- that results in no systematic bias for speech or handedness. Men superior at mental rotation and in spatial navigation. Object location memory (females) vs. mental rotation (males) Women more sensitive to all sensory stimuli except vision. Effects are found in young children and adults.
