Damage to categorical hemisphere usually leads to
. *categorical hemisphere is for sequential analytic processes and concerned with language function. *lesion in it produce language disorders and it can be fluent,nonfluent and anomic aphasias.ASSOCIATION AREAS Association areas form the "Inter-junction" for various cerebral coex pas. They paicularly connect motor & sensory areas. Mainly are associated with higher mental functions. Higher mental functions include speech, learning & memory and intellectual functions (insight, imagination etc.,) SENSORY ASSOCIATION AREA: This area provides primary interpretation of perceived sensation. Area included: 1. Brodmann's area 3,1,2 - Includes somatosensory coex. Perceives sensation of an object. 2. Brodmann's area 5 - Referred as "Somatosensory association area". Interprets the shape, size, & texture of sensation. 3. Brodmann's area 17 & 18 - Includes primary visual coex. Colors are perceived. 4. Brodmann's area 19 - Referred as "Visual association area" Identification of visual objects. 5. Brodmann's area 42 - Referred as "Auditory association area". Interprets the meaning of heard sound. MOTOR ASSOCIATION AREA: Includes, Premotor area (premotor coex & supplementary motor area). INTERHEMISPHERICAL DIFFERENCES: Right & left hemispheres are homologous & symmetrical regions of cerebral coex on either side of brain. They are connected together by long association fibers carried by corpus callosum. FUNCTIONS OF HEMISPHERES: Functional asymmetry usually exists between hemispheres. Most impoant functional asymmetry is exhibited by "Language". 1. Left hemisphere: Referred as "Dominant/Categorical hemisphere" Functions: Mainly represents language areas (Wernicke's area & Broca's area) - Both spoken & written language. Visual processing of written language. Auditory processing of spoken language. Language-related motor functions like speech, reading & writing. Detailed analytical abilities. Mathematical & scientific skills with reasoning. Complex motor planning activities. Mainly involves sequential analytical process & language. 2. Right hemisphere: Referred as "Non-dominant/Representation hemisphere" Ref Harrison20th edition pg 2367
Normal speech
Increased speech
Decreased speech
Senseless, fluent speech
C.N.S