Biopsychology Flashcards
What is the central nervous system broken up into?
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Role of the autonomic nervous system.
-Regulates involuntary physiological processes, for example heart rate, blood pressure, digestion ect.
Role of the somatic nervous system.
-regulates voluntary movements via the skeletal muscles, for example arm movements and speach.
What is the role of the sympathetic division of the autonomic system?
- Activated in times of stress, contros ‘fight or flight’ response. For example increasing of heart rate, dilation of pupils and readying muscles for activity.
- Also prevents rest and digest, digestion is put on hold as the body is preparing to fight or to run.
What is the role of the parasympathetic division of the autonomic nervous system?
- Helps maintain normal body function and conserve physical resources. Associated with the rest and digest system whereby a person is in rest mode. Change from the fight or flight response and returns the body to normal functionality.
- For example returning normal digestion and undilating pupils.
How does an FMRI work?
- Detects changes in blood oxygenation that occur as a result of neural activity in specific brain areas. When a brain area is more active, consumes more oxygen and therefore blood flow is redirected.
- This information is then used to create a 3D model which shows which areas of the brain are involved in specific mental processes.
What is the name of the process where blood is redirected to different brain areas?
-Haemodynamic response.
What is the process for Electroencephalogram (EEG)?
What are they primarily used for?
- Measure electrical activity within the brain using electrodes via a skull cap.
- Scan recordings show the brainwave patterns generated from millions of neurons- shows overall brain activity.
- Used primarily as a diagnostic tool. For example unusual arrhythmic patterns of brain activity may indicate abnormalities such as epilepsy, tumours or sleep disorders.
What is an ERP?
- Event-related potentials.
- These are what are left when all extraneous brain activity from an EEG recording is filtered out.
ERPs are collected using a statistical technique whereby brain waves that are left are responses that relate to the presentation of a specific stimulus.
-Put simply ERPs are types of brain waves that are triggered by particular events.
What kind of person is usually tested using post-mortem exams?
- Usually someone with a rare disorder or has experienced unusual deficits in cognitive processes or behaviours during their lifetime.
- The result from the post-mortem is then compared to someone of neural typical behaviour in order to assess the extent of difference and to figure out the cause of difference.
What are two strengths of the use of FMRI?
- Non-invasive. Unlike some scans such as PET scans they do not use radiation and does not involve the insertion of needles or probes into the brain. This increases the applicability of FMRIs and increase information that we know about the brain.
- The Use of FMRIs is highly scientific as it falsifiable. It uses a scientific method and process to gain information about the brain and as a result steps can be taken more easily to reproduce research. The scientific method to studying the brain increases the argument for psychology as a science as well as the replicability of FMRIs.
What are two weaknesses of FMRIs?
- Very expensive, one session can cost up to £500. Only used when necessary and only effective at capturing brain activity if a person lies very still. As a result of this research with the use of FMRIs may only use a small sample and as a result findings are difficult to generalise as research has low population validity.
- Temporal resolution of FMRIs is also very low as there is a 5 second lag between initial neural activity and image. FMRIs also only use mapping of oxygenated blood and as a result can not hone in on individual neural activity. This means that FMRIs do not give an up to date mapping of brain activity and data produced may be less quantitative and less easily scientifically interpreted.
What are two strengths of EEGs?
-EEG technology, unlike FMRIs for example have extremely high temporal resolution. They have been incredibly useful in the studying of stages of sleep and diagnostic of disorders such as epilepsy.
Epilepsy involves big bursts of activity in certain areas of the brain that can easily be detected on screen due to the high temporal resolution of EEGs. This shows the real-world usefulness of the technique.
-EEG is univasive, do not use radiation or insertion of instruments into the brain to map activity. Means its more applicable and more patients can make use of the mapping technique.
What is one weaknesses of EEGs?
-Low Spatial resolution. EEGs (and ERPs) can only make general assumptions regarding brain activity, only being able to pin activity to superficial regions of the brain. EEGs are unable to, unlike FMRIs, to pinpoint activity deep in the brain; such as activity of the hypothalamus. The FMRI is much more equipped for this as it has a spatial resolution of 1-2 mm.
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Outline Lashley’s research into brain localisation.
- She suggested that higher cognitive functions (e.g learning processes) are not localised but processed more holistically.
- Removed 10%-50% of the cortex in rats when learning a maze.
- She found that no area was of more importance in terms of maze orientating ability.
- This shows that processes such as learning require every part of the cortex rather than just particular areas. Suggests learning is too complex to be localised and involves the whole of the brain.
