Lashley’s research

• Lashley proposed the equipotentiality theory, which suggests that the basic motor and sensory functions are localised, but that higher mental functions are not.
• He claimed that intact areas of the cortex could take over responsibility for specific cognitive functions following brain injury.
• This therefore casts doubt on theories about the localisation of functions, suggesting that functions are not localised to just one region, as other regions can take over specific functions following brain injury.
• Lashley did this by removing from around 10-50% of the cortex in rats that were learning a maze.
• He noticed that no specific area of the brain seemed to more or less important than other areas. The process of learning seemed to require every part of the brain.
• This suggests that learning is too complex to be localised and requires the involvement of the whole brain.