1.1.1 Localisation of Brain Function (Bi) x Flashcards
How do we know which areas of the brain control which behaviour?
•Brain scans (functional) •Brain surgery
What are the two halves of the brain called?
The cerebral hemispheres
What are the cerebral hemispheres connected by and why?
The corpus callosum (250 million nerve cells) they need to be connected for the brain to function
How is behaviour explained?
In terms of different areas of the brain having specific functions (localisation of brain function)
What is the function of the left brain?
• logic • science and maths
What is the function of the right brain?
• creativity • art and music • holistic thought
What is the cerebral cortex? And what does it do?
The deeply folded area covering the surface of the brain, responsible for higher cognitive functions such as: • logic • dreams • hopes
What is the cerebral cortex divided into?
4 lobes: • frontal lobe • parietal lobe • occipital lobe • temporal lobe
What is the function of the frontal lobe?
Main site of higher cognitive functions, it is involved in: • attention • thought • voluntary movement • decision making • language
What would the results be of damage to the frontal lobe?
emotional instability, irrational decision making
Give an example of the effects of damage to the frontal lobe:
Phineas Gage was injured by a blasting rod which intersected the left side of his face, tearing through his prefrontal cortex. “The damage involved both left and right 4 prefrontal cortices in a pattern that, as confirmed by Gage’s modern counterparts, causes a defect in rational decision making and the processing of emotion”
+ Supporting evidence for localisation of brain function
Tulving et al
Tulving et al used PET scans
demonstrated that semantic memories were recalled from the left prefrontal cortex, whilst episodic memories were recalled from the right prefrontal cortex.
This shows that different areas of the brain are responsible for different functions, as predicted by localisation theory.
+ Supporting evidence for localisation of brain function
Petersen et al (1988)
Found that Wernicke’s area activation is required for listening tasks, whereas Broca’s area is required for reading tasks. This confirms the idea that Wernicke’s area is involved in speech comprehension, whilst broca’s area is responsible for language production.
— Contradictory Theory for localisation of brain function
The opposite to localisation theory would be a holistic view of brain function, suggesting that each function requires several brain areas to be activated and that these functions are not restricted to these areas. For example, after removing 20-50% of the cortices belonging to rats, found that no specific brain area or lesion was associated with learning how to traverse through a maze. This suggests that intelligence, or even learning, is too complex and advanced a cognitive ability to be restricted to certain areas of the brain. Therefore, this suggests that localisation theory may provide a better explanation for ‘simple’, rather than complex, brain functions.
What are the functions of the parietal lobe?
Part of the brain building a picture of the world, and our response to our environment involved in: • location of objects • coordination of movement