18 Connecting Link between Hemispheres Figure 14.1 Two views of the corpus callosum The corpus callosum is a large set of axons conveying information between the two hemispheres. (a) A sagittal section through the human brain. (b) A dissection (viewed from above) in which gray matter has been removed to expose the corpus callosum.
19 Visual Connections to the Hemispheres Visual Field-what is visible at any momentRight visual field-->left hemisphereLeft visual field-->right hemisphereCutting the Corpus CallosumSometimes done to treat severe epilepsyBehavior is abnormal only when sensory stimuli are limited to one side of the body
24 Split Hemispheres Competition Soon after surgery you may see competition between activities on the two sides of the bodyHemispheric SpecializationLeftSpeechMovement sequencingDetail-orientedRightEmotional content of speechRecognizes emotions in othersExpresses fear and angerSpatial RelationshipsMusic perceptionAnimation
25 Development of Lateralization and Handedness Anatomical Differences between the HemispheresPlenum temporale in left hemisphere largerCorpus Callosum is not fully developed at birthHandedness does not dramatically affect lateralizationMost left-handed people have left-hemisphere or mixed dominance for speech
26 Speech and Handedness First communication most likely hand signals Right hand preferred most humansRight hand controlled by left brainSignal language tied to spoken languageHand gestures to phonemesCommunication is left hemisphere task
27 Brain sculpted by experience Left hemisphere for speechRight for spatial tasksBoth hemispheres activeCan be resculpted if needed
28 Brain Science has come along way Still many mysteries to be solvedTreaments for brain diseasesUnderstanding the causesHope course has given you the knowledge to follow these developments