Biopsychology Flashcards
what are the two main functions of the nervous system?
- to collect, process and respond to information in the environment
- to co-ordinate the working of different organs and cells in the body
what does the Autonomic Nervous System (ANS) do?
governs vital functions in the body such as breathing, heart rate, digestion, sexual arousal and stress responses
what does the Somatic Nervous System Do (SNS) do?
governs muscle movement and receives information from sensory receptors
what does the pituitary gland do?
controls the release of hormones from all the other endocrine glands in the body
where is the Motor area and what does it do?
- back of the frontal lobe
- Involved in the planning, control and carrying out of voluntary movement
where is the somatosensory area and what does it do?
- front of the parietal lobe
- processes sensory information such as touch, pain, thermal sensation and position
where is the visual area and what does it do?
- rear part of the occipital lobe
- receives and processes visual information
where is the auditory area and what does it do?
- temporal lobe
- concerned with the analysis of speech-based information, or auditory stimuli, such as music
where is the Broca’s area and what does it do?
- frontal lobe in the left hemisphere
- responsible for speech production
where is the Wernicke’s area and what does it do?
- temporal lobe in the left hemisphere
- responsible for language comprehension
localisation of function evaluation
- evidence through brain scans (Peterson 1988)
- Lashley rats experiment
- Phineas gage
Findings of split-brain research
Object shown to RVF:
- participant can describe what is seen (language centres in LH)
Object shown to LVF:
- cannot name object (no language centres in RH)
- can select matching object behind screen using left-hand
- can select object closely associated with picture
- pinup picture shown to LVF, participant giggled but reported seeing nothing
evaluation of split-brain research
- uses of highly specialised and standardised procedures
- Evidence for hemispheric lateralisation being a feature of the normal brain as well as split brain
- idea of analyser vs synthesiser brain may be wrong
- split brain patients are rare so lack of generalisability
what is plasticity?
- the apparent ability of the brain to change and adapt its structures and processes as a result of experience and new learning
- Between the ages of 2-3 are when the growth in the number of synaptic connections peaks but continues to increase throughout
what is functional recovery?
the way that certain abilities of the brain may be moved or redistributed to undamaged areas, rather than lost, following damage or trauma to the brain
Plasticity and functional recovery evaluation
- research support Hubel and Wiesel (1963)
- research support - black cab drivers
- plasticity may not always be beneficial
- plasticity may not decline sharply with age
functional recovery after trauma
- Neuroscientists suggest that this process can occur quickly after trauma (spontaneous recovery) and then slow down after several weeks or months
- The brain is able to rewire and reorganise itself by forming new synaptic connections close to the area of damage
- Secondary neural pathways are activated to enable functioning to continue, often in the same way as before
- This process is supported by a number of structural changes in the brain including:
- Axonal sprouting – the growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways
- Reformation of blood vessels
- Recruitment of homologous (similar) areas on the opposite side of the brain to perform specific tasks
- an example is Gabby Giffords
what is fMRI?
- Functional magnetic resonance imaging is a method used to measure brain activity whilst a person is performing a task that uses MRI technology
- Enables the researchers to detect regions of the brain that are rich in oxygen, and hence are active
- fMRI works by detecting the changes in blood oxygenation and flow that occur as a result of neural (brain) activity
- when a brain area is more active it consumes more oxygen and to meet this increased demand blood flow is directed to the active area (known as haemodynamic response)
- fMRI produces three-dimensional images showing which parts of the brain are involved in a particular mental process and this has important implications for our understanding of localisation of function
strengths and weaknesses of fMRI
Strengths:
- non invasive due to no radiation used
- useful in investigating some disorders, such as OCD
- plays a role in investigating cognitive theories
Weaknesses:
- expensive and can only capture a clear image if the person stays completely still
- poor temporal resolution because there is a time-lag of several seconds between the initial firing of neuronal activity and what the scanner can detect and show on the screen
- can only look at the blood-flow in the brain
What are EEGs?
- An electroencephalogram is a record of the tiny electrical impulses produced by the brain’s activity
- EEGs measure electrical activity within the brain via electrodes that are fixed to an individual’s scalp using a skull cap
- The scan recording represents the brainwave patterns that are generated from the action of millions of neurons, providing an overall account of brain activity
Strengths/weaknesses of EEGs
Strengths:
- High temporal resolution (can detect brain activity at a resolution of a single millisecond)
- Used to diagnose conditions such as epilepsy
Weaknesses:
- Generalised nature of the information received (not useful for pinpointing the exact source of neural activity)
- Cannot be used in many situations where we want to investigate brain activity
what are ERPs?
- types of brain wave that are triggered by particular events
- This is found by isolating and filtering out all extraneous brain activity from an EEG, using a statistical averaging technique
Strengths/Weaknesses of ERPs
Strengths:
- More specific than EEGs
- Proven useful in many areas of investigation e.g. OCD
Weaknesses:
- Lack of standardisation in ERP methodology between different research studies, which makes it difficult to confirm findings
- Cannot be used to study most complex cognition due to these involving several different processes spread over a long period of time
- Poor spatial resolution
What are Post-mortem examinations?
- It is a technique involving the analysis of a person’s brain following their death
- The brain is analysed to determine whether certain observed behaviours during the patient’s lifetime can be linked to abnormalities in the brain
Strengths/Weaknesses in post-mortem examinations
Strengths:
- Provided a foundation for the early understanding of key processes in the brain
- Improved medical knowledge and helped provide hypotheses for further study
Weaknesses:
- Difficulty interpreting the results
- The relationships found are correlational rather than providing evidence of causation
