Hemispheric Lateralisation Flashcards
Lateralisation of function
The brain is split into two hemispheres which are connected by a bundle of nerve fibres called the corpus callosum. Psychologists look at the idea of lateralisation- the idea that the two halves of the brain are functionally different and certain mental processes are mainly controlled by one hemisphere over the other.
What does the left hemisphere deal with
Words and language as it contains wernickes and brocas area
The brain is contralateral - what does this mean?
The right side of the body is controlled by the left hemisphere and the left side of the body is controlled by the right hemisphere. The corpus callosum communicates the information to the other hemisphere to make us fully able to interact and deal with our surroundings.
What does the right hemisphere deal with
Objects and face recognition
Left and Right Visual Field
The right hemisphere controls the left visual field of both eyes
The left hemisphere controls the right visual field of both eyes
Sperry - split brain research
11 split brain and 11 non split brain patients - matched pairs on IQ and gender (male)
Lab + quasi experiment
Method - stare at screen and fixate on cross - flash word, object or face onto RVF or LVF of screen - participant had to say, draw or match
Controls included one eye blindfolded, hands in box, flash for 1/10 of second, fixate on cross
Language - RVF - LH - CAN SAY LVF - RH - CAN’T SAY
Object Recognition - RVF - LH - DRAW POORLY LVF - RH - DRAW WELL
Face recognition - RVF - LH - CAN’T MATCH. LVF - RH - CAN MATCH
LH - language RH - objects and faces
EVALUATION - Is the brain lateralised to specialise in specific functions for each hemisphere or do we use both hemispheres for all functions
STRENGTH - highly scientific research support - Sperry high controls - shows strong causation and also used matched pairs design so extraneous variables removed - sample however still had individual differences such as the extent of their surgery also doesn’t account for plasticity
STRENGTH - research from animal studies - Roger’s et al found in chickens brain lateralisation is associated with performing two tasks simultaneously finding food and being vigilant - evolutionary and necessary for survival in all mammals - however humans are predators so de lateralisation is more advantageous as we need to be able to use all of our brain for complex functions
LIMITATION - lateralisation changes with age - after 26 lateralisation decreased with each decade of life - too simplistic as we need to see how hemispheres function together for more complex processes - however brain does start lateralised and we are not certain whether or not dematerialisation is a negative due to decay or positive by the brain improving
EVALUATION - Is the brain lateralised to specialise in specific functions for each hemisphere or do we use both hemispheres for all functions
STRENGTH - highly scientific research support - Sperry high controls - shows strong causation and also used matched pairs design so extraneous variables removed - sample however still had individual differences such as the extent of their surgery also doesn’t account for plasticity
STRENGTH - research from animal studies - Roger’s et al found in chickens brain lateralisation is associated with performing two tasks simultaneously finding food and being vigilant - evolutionary and necessary for survival in all mammals - however humans are predators so de lateralisation is more advantageous as we need to be able to use all of our brain for complex functions
LIMITATION - lateralisation changes with age - after 26 lateralisation decreased with each decade of life - too simplistic as we need to see how hemispheres function together for more complex processes - however brain does start lateralised and we are not certain whether or not dematerialisation is a negative due to decay or positive by the brain improving
