Biopsychology Flashcards
Describe the motor cortex
Controls the muscles via the spinal cord
In the front lobe of both hemispheres
Different parts control specific areas of body
Cortex on right side controls left side
Cortex on left side controls right side
Describe the Broca’s area
One of the language areas involved in speech production.
It is situated on the left hemisphere (in most people) close to the motor cortex that controls the mouth
Describe the auditory centres of the brain
Located in the temporal lobes on both sides of the Brain
Information from the ears is processed in different areas of the brain but ends up in the auditory cortex where it is recognised and responded too
Describe the wernicke’s area of the brain
Another language centre
Involved in language comprehension and anomia
Situated near the junction of the left temporal and partial lobes
What is wernicke’s aphasia
Difficulty understanding language may speak nonsense or make up words
How is the Broca’s area and the wernicke’s area connected
Neural loop
Describe the visual centre of the brain
Many areas in brain involved in processing visual info
This is the main area for detecting patterns and processing info about moving objects
Visual cortex in the occipital lobe
What may occur if there is damage to the visual cortex of the brain
Damage to left may mean individual is blind in right field of vision
Vice verca
Describe the somatosensory cortex
Responsible for the sensation of touch
Distributed across the parietal lobes and receives information from opposite side of body to lobe
More areas in the cortex is given over to areas of the body with a lot of sensory receptors such as fingers and lips
(In both hemispheres)
What is a strength of localisation of function of the brain
Supporting evidence
Development of brain scanning techniques such as fMRI providing objective scientific evidence for idea that different areas of brain perform different functions
One study of Broca’s area was active when reading out loud
Another study found semantic memories are associated with pre-frontal cortex whereas episodic memories are associated with the left pre frontal cortex ( tulving et al)
Findings support for localisation of function
What is a weakness of localisation of the brain
Challenging evidence
Research shows functions such as learning does not appeared to be linked to specific area, processed in many
One study investigated impact of learning a maze on rats who each had different parts of their cortex removed
No brain area was found more important for learning than others
Also found learning involved numerous parts of the cortex rather than localised areas
Suggests some processes require all parts of brain not specific regions
What is localisation of function in the brain
The idea that different part of the brain are responsible for particular skills and abilities (functions)
What is the outer layer of the brain called
The cerebral cortex
How many hemispheres are in the cerebral cortex
2
Left and Right
How are the two hemispheres of the brain connected
Via the corpus callosum
What is plasticity
The brains ability to adapt its structure and the way it processes information
E.g if the left motor cortex becomes damaged the right motor cortex can take over
What are two examples of plasticity
Pruning
Bridging
What is pruning
When brain connections are lost due to lack of use
What is bridging
Where new connections are created due to use and stimulus
Who studied plasticity using taxi drivers
Maguire et al
Explain maguires research into plasticity
Studied brains of London taxi drivers, specifically the hippocampus
Used matched pairs to study 16 healthy taxi drivers, the control group was the same age matched on health non taxi drivers
Found London taxi drivers had more neuron cell body’s in their right and left posterior hippocampus than participates in the control
A positive correlation was found
What is a strength of localisation of function of the brain
Development of brain scanning - fMRI provides objective, scientific supporting evidence for idea different brain areas perform different functions
One study found Broca’s area active when reading out loud.
Another study found memories associated with right pre-frontal cortex
Findings support localisation of function
What are the weaknesses of localisation of function of the brain
There is challenging evidence - some research has shown that functions like learning are not appeared to link to specific brain locations - processed by many
One study investigated rats learning a maze who each had different part of cortex removed - no brain area found more important than others
Also found learning involved numerous parts of cortex - suggests some processes require all parts of brain not specific regions
Further evidence - challenged idea of localisation of function comes from research into plasticity.
People with brain damage and lose specific cognitive functions are sometimes able to functionally recover these abilities as brain reorganised itself
This suggests specific functions not confined to specific areas but other parts of the brain are able to fulfil lost function when needed.
This would suggest that the brain operates on a holistic (overall) rather than localised basis
What is hemispheric lateralisation
This means that some functions of the brain are controlled by one hemisphere and not the other
What is the role of the left hemisphere
Responsible for speech and language
More active processing fine details
Logical and mathematical
What may be the outcome if a person has a stroke effecting the left hemisphere of the brain
Their ability to speak may be affected.
This is because Broca’s and Wernicke’s area are located exclusively in the left hemisphere
What is the right hemisphere of the brain responsible for
Visual and spatial processing
Processing the ‘bigger picture’
Recognising emotions and faces
What is an example of the left hemisphere processing fine detail
When looking at a picture, the left side of the brain will process the small intricate details
What is an example of the right hemisphere involving visual and spatial processes
A case study of a women with right hemisphere damage found she quickly became lost even in familiar settings unless she had verbal instructions with visual cues such as ‘turn right at the post box’
What is an example of the right hemisphere processing the bigger picture
When looking at a picture the right is active when looking at its whole, suggesting overall patterns
What is an example of the right hemisphere of the brain processing emotions and recognising faces
A study found when people were shown a split fave where one was half smiling one was neutral. The emotion indicated by the left side of the face was the one reported most often
The left visual field is processed by the right hemisphere
What happens if the visual centre is damaged
Damage to the left hemisphere - right eye may go blind
Damage to right hemisphere - left eye might go blind
What happens if the Broca’s area is damaged
People often suffer from Broca’s aphasia
Producing speech requires great effort, is slow and laboured
Speech lacks fluency in that words that help sentences function ‘it’ or ‘the’ are often missing
May be produce meaningful sentences but ones containing few words
What happens if the wernicke’s area is damaged
People who damage this suffer from wernicke’s aphasia
They can produce language and speak fluently
They have difficulty understanding languages so they often say nonsense or make words up
What happens if there is damage to the motor centres of the brain
There will be an issue with movement
What happens if you damage the somatosensory centre
You may have issues with pain tolerance it may be higher or lower
What happens if you damage the auditory centre
Potential hearing problems
What is a strength of hemispheric lateralisation?
There is an advantage of using lateralisation
It is often assumed whilst one hemisphere is occupied with a task the other is free to deal with another process so we can increase our capacity to process information
Eg we can process a language and spatial task at the same time.
One study in chickens found brain lateralisation enabled a chicken to forage for food and remain vigilant for predators
This suggests the idea of lateralisation seeks to be an effective way to process information and utilise brain capacity’s
What are weaknesses of research into hemispheric lateralisation
Challenging evidence
Turk et al - patient who suffered damage to left hemisphere developed capacity to speak using right hemisphere eventually leading to ability to speak about information presented to either hemisphere.
Suggests lateralisation of function is not a fixed characteristic of the brain and it can adapt following damage.
Weakness of research - loose confidence due to counter evidence question validity of research conducted
Challenging evidence - researched found language became more lateralised to left hemisphere with increasing age but after 25 lateralisation decreased each decade.
Suggests lateralisation changes / implies lateralised brain is only a feature of young children and adults - not true beyond adulthood
Weakness - question validity of original research due to counter evidence
Why was split brain surgery orgininally conducted
To treat patients with severe epilepsy
Describe what a split brain is
Surgery to remove the corpus callosum that connects two hemispheres - prevents each hemisphere communicating with the other
Who conducted research into split brains
Sperry et al
Explain the procedure of research into split brains
Sperry et al
Split brain individual would fixate on a dot in centre of screen while info briefly presented to right or left visual field or both
Patient asked to describe what was seen or select object that was presented on screen with left or right hand (objects behind a screen)
Words shown to right visual field were easily described because images presented to right side are processed in left hemisphere where the language centres are based .
Words shown to left visual field could not be described, however they could draw the word or pick up an item associated with the word.
Two words that represent an object E.g key and ring presented but participants could only pick up a key with left hand and recall word ‘ring’ as was processed by left hemisphere
In split brain research, what field of vision could participants see and recall
Word shown on right visual field could be described as this goes to left hemisphere where the language centres are
What had split brain research taught us
Left hemisphere is responsible for speech and language
Right hemisphere specialises in visual-spatial processing and facial recognition
Sperry concluded right hemisphere is capable of very basic language processing (recognising language) but more complex language tasks (speaking)
Split brain research not shown brain organisation in specific regions just that connectivity between regions is very important as the operation for different parts
Strengths of split brain research
Supporting evidence
Research indicates left hemisphere in charge of language and speech and right involved in visual and spatial processing as well as face recognition
Also evident two hemispheres need to communicate and contribute own processes to be successful overall functioning
Strength - research has strong evidence showing importance of corpus callosum and clear indication of hemispheric processing
Weaknesses of split brain research
Methodological issues
Split brain - rare procedure so few patients to be studied
Sperry’s research used 11 participants (small sample size) took part in all variations of study.
Low ecological validity as hard to generalise confidently regarding brain functioning from small sample size.
Split brain procedures also carried out on individuals with serious brain functioning problems that necessitated such surgery.
Weakness - we cannot confidently assume their responses after surgery are result only of two hemispheres being separated.
Challenging evidence
Gazzangia argued right hemisphere is able to handle language better than Sperry assumed
One patient (JW) developed capacity to speak using right hemisphere
Suggests language may not be exclusively limited to left hemisphere
Supports idea of brain plasticity as before surgery JW processed language in left hemisphere.
Weakness - shows brain can recover functions after physical trauma, loose confidence in accuracy of findings of Sperry’s research
What part of the brain is the motor cortex in
Very back of Frontal lobe, both hemispheres
What is the outer layer of the brain called
Cerebral cortex
Where is the somatosensory cortex
Behind motor cortex in parietal lobe, both hemispheres
Where is the visual cortex
Occipital lobe, both hemispheres
Where is the auditory cortex
Temporal lobe, both hemispheres
Who conducted challenging evidence for hemispheric lateralisation briefly what was it
Turk et al - patient could speak using right hemisphere
Who conducted challenging research to Sperry’s split brains
Gazzaniga
What was the name of the patient used in the split brain challenging evidence
JW
What is plasticity
Refers to the brains ability to change and adapt its structure and the way it processes information