BIOPSYCHOLOGY
Localisation of Function
The idea that different area of the brain are responsible for different processes, behaviours or activities
The brain is divided into 2 hemispheres – each responsible for different functions
e.g., left hemisphere responsible for logic, right hemisphere responsible for creativity
left hemisphere responsible for right hand side of the body, right hemisphere responsible for left hand
side of the body
The outer layer of the hemispheres is the cerebral cortex – made up of tightly packed neurons,
responsible for higher thought processes such as speech + decision making
It covers 4 different lobes – each processing different type of sensory information
Frontal lobe [location for awareness of what we are doing within our environment +
movements]
Perioral lobe [location for sensory information related to touch]
Temporal lobe [location for auditory information + understanding of language]
Occipital lobe [location for vision]
Motor Area...
▫ located in frontal lobe
▫ responsible for voluntary movements by sending signals to muscles
▫ in both hemispheres [motor area in left hemisphere controls right side of the body, vice versa]
▫ different part of motor area are responsible for different parts of the body; arranged logically
e.g., region controlling leg is next to region controlling foot
Somatosensory Area...
▫ located in perioral lobe
▫ receives information from sensory receptors in the skin to produce sensations like pain,
pressure; then localises to specific regions
▫ in both hemispheres [one side receives sensory information from opposite side of the body]
Auditory Area...
▫ located in temporal lobe
▫ analyses + processes acoustic information
▫ primary auditory area processes simple features of sound e.g., sound, tempo
Visual Area...
▫ located in occipital lobe
▫ receives + processes visual information
, ▫ has different areas processing different types of information e.g., colour, shape
Language is restricted to left hemisphere in most people:
Broca’s area – located in small area in left frontal lobe, responsible for speech
production – if damaged, can lead to Broca’s aphasia – slowed speech that doesn’t
always make sense
Wernicke’s area – located in area in left temporal lobe, responsible for language
comprehension – if damaged, can lead to Wernicke's aphasia – produces nonsense
speech + unable to understand language
Case Study – Phineas Gage [worked on rail line, 1848]
▫ explosion hurled metre length pole through left cheek, passed behind left eye, exiting top of his
head [mostly left frontal lobe]
▫ survived but experienced changes in personality from calm + reserved to quick-tempered + rude
▫ provides evidence as area damaged believed to be associated with personality + regulation of
mood – became irregular + irrational
strength: brain scan evidence e.g., Peterson et al found Wernicke’s area active when performing
listening tasks + Broca’s area active when undertaking reading tasks, so supports that different areas are
responsible for different function
strength: support from case study, e.g., Phineas Gage [list what happened], experienced changes in
personality from calm + reserved to quick-tempered + rude, demonstrates localisation, area damaged
linked to logic, personality + regulation of mood, so valid theory
weakness: does not account all areas in the brain, Lashley argues equipotentiality, higher cognitive
processes like learning not localised, but distributed holistically, e.g., removed 10-50% of cortex in rats’
brains, they learn maze but found no particular area was more important in helping ability to complete
maze, suggests learning requires every part of cortex, too complex to be localised, so supports more
holistic theory – too broad
strength: damaged area in the brain linked to mental disorders, neurosurgery last resort in treating
mental disorders is to target specific areas involved, e.g., Doughley et al reported 44 OCD patients
undergone citotolomy, found a third of patients significantly improved + further 14% particularly
improved, so shows behaviours + symptoms associated with mental disorders are localised
Hemispheric Laterisation
The brains 2 hemispheres are responsible for different functions; one hemisphere is
dominate/specialised in a function, whilst the other is not
e.g., left hemisphere with logic + right hemisphere with creativity
The 2 hemispheres are connected by nerve fibers called the corpus callosum, which facilitate
interhemispheric communication, allowing the left + right hemispheres to ‘talk to each other’
Localisation of Function
The idea that different area of the brain are responsible for different processes, behaviours or activities
The brain is divided into 2 hemispheres – each responsible for different functions
e.g., left hemisphere responsible for logic, right hemisphere responsible for creativity
left hemisphere responsible for right hand side of the body, right hemisphere responsible for left hand
side of the body
The outer layer of the hemispheres is the cerebral cortex – made up of tightly packed neurons,
responsible for higher thought processes such as speech + decision making
It covers 4 different lobes – each processing different type of sensory information
Frontal lobe [location for awareness of what we are doing within our environment +
movements]
Perioral lobe [location for sensory information related to touch]
Temporal lobe [location for auditory information + understanding of language]
Occipital lobe [location for vision]
Motor Area...
▫ located in frontal lobe
▫ responsible for voluntary movements by sending signals to muscles
▫ in both hemispheres [motor area in left hemisphere controls right side of the body, vice versa]
▫ different part of motor area are responsible for different parts of the body; arranged logically
e.g., region controlling leg is next to region controlling foot
Somatosensory Area...
▫ located in perioral lobe
▫ receives information from sensory receptors in the skin to produce sensations like pain,
pressure; then localises to specific regions
▫ in both hemispheres [one side receives sensory information from opposite side of the body]
Auditory Area...
▫ located in temporal lobe
▫ analyses + processes acoustic information
▫ primary auditory area processes simple features of sound e.g., sound, tempo
Visual Area...
▫ located in occipital lobe
▫ receives + processes visual information
, ▫ has different areas processing different types of information e.g., colour, shape
Language is restricted to left hemisphere in most people:
Broca’s area – located in small area in left frontal lobe, responsible for speech
production – if damaged, can lead to Broca’s aphasia – slowed speech that doesn’t
always make sense
Wernicke’s area – located in area in left temporal lobe, responsible for language
comprehension – if damaged, can lead to Wernicke's aphasia – produces nonsense
speech + unable to understand language
Case Study – Phineas Gage [worked on rail line, 1848]
▫ explosion hurled metre length pole through left cheek, passed behind left eye, exiting top of his
head [mostly left frontal lobe]
▫ survived but experienced changes in personality from calm + reserved to quick-tempered + rude
▫ provides evidence as area damaged believed to be associated with personality + regulation of
mood – became irregular + irrational
strength: brain scan evidence e.g., Peterson et al found Wernicke’s area active when performing
listening tasks + Broca’s area active when undertaking reading tasks, so supports that different areas are
responsible for different function
strength: support from case study, e.g., Phineas Gage [list what happened], experienced changes in
personality from calm + reserved to quick-tempered + rude, demonstrates localisation, area damaged
linked to logic, personality + regulation of mood, so valid theory
weakness: does not account all areas in the brain, Lashley argues equipotentiality, higher cognitive
processes like learning not localised, but distributed holistically, e.g., removed 10-50% of cortex in rats’
brains, they learn maze but found no particular area was more important in helping ability to complete
maze, suggests learning requires every part of cortex, too complex to be localised, so supports more
holistic theory – too broad
strength: damaged area in the brain linked to mental disorders, neurosurgery last resort in treating
mental disorders is to target specific areas involved, e.g., Doughley et al reported 44 OCD patients
undergone citotolomy, found a third of patients significantly improved + further 14% particularly
improved, so shows behaviours + symptoms associated with mental disorders are localised
Hemispheric Laterisation
The brains 2 hemispheres are responsible for different functions; one hemisphere is
dominate/specialised in a function, whilst the other is not
e.g., left hemisphere with logic + right hemisphere with creativity
The 2 hemispheres are connected by nerve fibers called the corpus callosum, which facilitate
interhemispheric communication, allowing the left + right hemispheres to ‘talk to each other’
