Hemispheres

• Hemispheric Lateralisation is when the two halves of the brain are functionally different so certain mental processes are controlled by one hemisphere
• Each half of the body is controlled by the opposite hemisphere
• The left hemisphere controls logic & analytic thought, language & speech, maths & science,
• The right hemisphere controls creativity & imagination, intuition, face recognition, navigating spacially etc
• The Corpus Callosum is a thick bundle of nerves connecting the two hemispheres which ensures both sides can communicate and send signals to each other
• Sperry & Gazzaniga used split-brain patients who had undergone a surgical procedure where the corpus callosum is cut in an attempt to cure epilepsy
• A lack of left hemisphere means that the patients are unable to use written/spoken language or name objects/letters/numbers
• A lack of right hemisphere means that the patients are unable to draw objects accurately, copy a design or recognize facts/complex visual objects
• Sperry & Gazzaniga used a small sample size and only studied patients with epilepsy so has low generalisability
• Sperry & Gazzaniga's experiment had low mundane realism as it does not reflect how we use our brains in real life
• When a word was flashed to the left field of view, the patient was unable to say what they saw but was able to draw it
• Equipotentiality theory is that basic motor and sensory functions are localised but higher processes aren't so that other areas can take over if there in brain injury