hemispheric lateralisation

• localisation of function:

  some functions such as vision and language are governed by specific areas in the brain. for some functions the localised areas appear in both hemispheres
• brocas area is in the left frontal lobe
• wernickes area left temporal lobe
• right hemisphere only produce rudimentary words and phrases but can contribute to emotional context
• left hemisphere analyser and right hemisphere synthesiser
• many functions are not lateralised such as vision and somatosensory areas
• motor area is lateral wiring right hemisphere left side of body left hemisphere right side of body
• vision highly complex as its contra and ipsi lateral left visual field both eyes on right hemisphere
• +research showing that even in connected brains hemispheres process info differently. fink 1996 pet scans identify which brain areas are active. when pps connected brains asked to attend global elements of an image regions rh more active. required focus on fine details lh hemisphere active. suggests hemispheric lateralisation feature of connected brain and split brain
• -idea lh analyuser rh synthesiser may be wrong. may be diff functions in rh and lh nut research suggests ppl dont have a dominant side of the brain which creastes a diff personality. nielsen 2013 analysed brain scans from 1000+ age 7-29 and found that ppl used certain hemispheres for diff functions but no evidence for dominant side. suggestion notion of left and right brained ppl wrong
• lateralisation is adaptive as enables two tasks to be performed simultaneously with greater efficiency. rogers 2004 showed that lateralised chickens could find food while watching for chicken but normal chickens couldnt . but neural plasticity seen as adaptive following damage due illnesses as some functions can be taken over by non-specialised areas in opposite areas