Biopsychology – Localisation of Function in the Brain
TWO RESEARCHERS: Broca and Wernicke
- They believe in localisation of function in the brain, this means that different areas of the brain
are associated with particular behaviours, processes or activities.
- Before the 19th century, most scientists believed in a holistic theory of the brain – ALL parts of the
brain are involved in behaviours, processes or activities.
Phineas Gage
Had an accident where a pole travelled straight through his prefrontal cortex.
If we took the holistic theory of the brain, we would assume that Phineas would lose all functions
because one of his parts of the brain was damaged, this would mean it would affect his whole brain.
However, although Phineas’ personality changed as he became more aggressive – he still surivived.
Front lobe regulates mood – as this is the area that was damaged, this lead to significant changes in
Phineas’ mood and personality.
This shows areas of the brain are associated with specific functions, demonstrating the
localisation of function.
Problems –
1. We do not know what he was like before, it is very difficult to compare before and after – cause and
effect relationship cannot be identified. Could have just been the trauma of the accident that caused
personality changes instead of the actual incident.
2. He is one individual so research cannot be replicated, so findings are not generalisable (case study) –
study has low population validity.
Hemispheres of the Brain and the Cerebral Cortex
The brain is divided into the right and left hemispheres.
Activity on the left-hand side of the body is controlled by the right hemisphere, activity on the
right-hand side of the body is controlled by the left hemisphere.
The outer layer of both hemispheres is the cerebral cortex, this is a 3mm thick layer covering the
inner parts of the bain, it is much more developed in humans than other animals (this is what is
thought to set human cognitive functioning apart from animals).
Parts of the brain
Frontal lobe – motor area – A
Parietal lobe – somatosensory area – L
Occipital lobe – visual area - C
Temporal lobe – auditory area – D
FUNCTIONS
Motor area – controls fine movement of the hands, feet, tongue and face. Responsible for voluntary
behaviour e.g., lifting your arm or walking. If damaged may lead to involuntary movements such as spasms
or ticks.
Somatosensory area – receives sensory information from the skin senses such as touch, heat and pressure.
If damaged, less sensitivity to touch, heat, pressure.
TWO RESEARCHERS: Broca and Wernicke
- They believe in localisation of function in the brain, this means that different areas of the brain
are associated with particular behaviours, processes or activities.
- Before the 19th century, most scientists believed in a holistic theory of the brain – ALL parts of the
brain are involved in behaviours, processes or activities.
Phineas Gage
Had an accident where a pole travelled straight through his prefrontal cortex.
If we took the holistic theory of the brain, we would assume that Phineas would lose all functions
because one of his parts of the brain was damaged, this would mean it would affect his whole brain.
However, although Phineas’ personality changed as he became more aggressive – he still surivived.
Front lobe regulates mood – as this is the area that was damaged, this lead to significant changes in
Phineas’ mood and personality.
This shows areas of the brain are associated with specific functions, demonstrating the
localisation of function.
Problems –
1. We do not know what he was like before, it is very difficult to compare before and after – cause and
effect relationship cannot be identified. Could have just been the trauma of the accident that caused
personality changes instead of the actual incident.
2. He is one individual so research cannot be replicated, so findings are not generalisable (case study) –
study has low population validity.
Hemispheres of the Brain and the Cerebral Cortex
The brain is divided into the right and left hemispheres.
Activity on the left-hand side of the body is controlled by the right hemisphere, activity on the
right-hand side of the body is controlled by the left hemisphere.
The outer layer of both hemispheres is the cerebral cortex, this is a 3mm thick layer covering the
inner parts of the bain, it is much more developed in humans than other animals (this is what is
thought to set human cognitive functioning apart from animals).
Parts of the brain
Frontal lobe – motor area – A
Parietal lobe – somatosensory area – L
Occipital lobe – visual area - C
Temporal lobe – auditory area – D
FUNCTIONS
Motor area – controls fine movement of the hands, feet, tongue and face. Responsible for voluntary
behaviour e.g., lifting your arm or walking. If damaged may lead to involuntary movements such as spasms
or ticks.
Somatosensory area – receives sensory information from the skin senses such as touch, heat and pressure.
If damaged, less sensitivity to touch, heat, pressure.
