EVALS Lateralisation

• Eval points for lateralisation


  • s - Sperry's conc that the left hemisphere is responsible for verbal tasks and the right is for performing spacial tasks have led to further research and applications in the field
  • s - sperry et al's research - involves innovative and ingenious methodology which enabled scientific study of split brain patients.
  • w - lateralisation changes with age
  • w - research that supports lateralisation can't be generalised and has questionable internal v
• s - Sperry's conc that the left hemisphere is responsible for verbal tasks and the right is for performing spacial tasks have led to further research and applications in the field. It has helped innovate rehabilitation programmes that focus on verbal/visual spatial therapy for brain damage depending on which area is damaged. This is done by using mild electrical stimulation of the damaged area. This will lead to neuronal growth. Thus the understanding of lateralisation has helped improve the lives of those suffering from brain damage by accelerating the rate of recovery. Increase utility
• s - sperry et al's research - involves innovative and ingenious methodology which enabled scientific study of split brain patients. Due to the individually unique nature of split brain patients, Rs had difficulty inventing S.P. to use on all split brain Ps. Sperry's original method of blindfolding one eye and making Ps fixate on a cross and shown an image for a tenth of a second was objective, operationalised, standardised and replicable. Thus reliability of findings can be tested. Increases scientific rigour of the findings and our understanding increases V
• w - lateralisation changes with age. Lateralisation of function appears not to stay exactly the same throughout an individual's lifetime but changes with normal aging. E.g. Szaflarski et al found that lang became more lateralised to the left hemisphere throughout childhood and adolescence but after the age of 25, lateralisation decreases and the function of lang become more bilateral with each decade of life. W bc ...
• (W - lateralisation changes with age)... W bc - shows the brain doesn't work in a lateralised way throughout life. The fact that the brain changes to bilateral patterns as you age makes us Q Sperry's conc regarding lateralisation. If lateralisation is the brain's way of functioning, it should be demonstrated in individuals of all ages. Thus incomplete model. Decrease V
• w - research that supports lateralisation can't be generalised and has questionable internal v. In Sperry's experiment all 11 Ps had history of epileptic seizures. Also, while all Ps had their corpus callosum damaged, some had other connections between left and right hemisphere (e.g. anterior commissure) intact. W bc ...
• (w - lacks generalisability and internal v)... W bc Ps being epileptic and suffering from seizures means their brains are fundamentally diff from neurotypicals. Therefore, can't generalise findings of brain functioning to neurotypicals. For internal V, although they believed they were measuring fully split brain Ps, some weren't fully split brain. Means the degree of disconnection between Ps varied greatly. Bc of the lack of generalisability and lack of internal V, the overall v decreases