Localisation of function evaluation Flashcards
What was Peterson et al’s brain scanning research?
Demonstrated that the Wernick area was active during a listening task and Broca’s area was active during a reading task suggesting they have different functions
What was Tulving’s brain scanning research?
Revealed that semantic and episodic memories reside in different parts of the pre-frontal cortex
What neurosurgical techniques were developed during the 1950’s?
That of Walter Freeman who developed the lobotomy - these methods were imprecise and involved severing connections in the frontal lobe in an attempt to control aggressive behaviour - today is rarely used except in severe cases of OCD and depression
What was Dougherty et al’s research?
Reported on 44 OCD patients who had undergone a cingulotomy (lesioning of the cingulate gyrus) - at the post surgical follow up 32 weeks later, 1/3 met the criteria for a successful response and 14% a partial response - supports the idea that symptoms and behaviours of those that are seriously mentally ill are localised
What was the case of Phineas Gage and how does it support localised functioning?
When working on a railroad in 1848 he was involved in an explosive accident - a metre long pole went through his left cheek, eye and exited his skull from the top taking a section of the brain, the frontal lobe
He survived but had significant changes in personality -from calm to quick tempered. Suggests frontal lobe helps regulate mood
What was Lashley’s research?
He suggested that higher cognitive functions such as those involved in learning are not localised but distributed in a more holistic way
He removed between 10 and 50% of the cortex in rats that were learning a maze, The process of learning appeared to use every part of the brain rather than being confined to one area - suggests learning is too complex to be localised
What is another argument against localisation?
Plasticity
How is plasticity against localisation?
When the brain in damaged through illness and accident and a particular function has been lost then the rest of the brain is able to reorganise itself in an attempt to recover some lost function. The law of equipotentiality where surviving brain circuits chip in so the same neurological action can be achieved
Doesn’t always happen but can be seen in stroke victims
