Biopsychology Flashcards
Scanning techniques- DEFINE Electroencephalogram (EGG)
A method of recording changes in the electrical activity of the brain using electrodes attached to the scalp.
When these signals are graphed over time the representation is called an EEG.
Scanning techniques- ERP
Event-related potential (ERP)
A technique that takes raw EEG data and uses it to investigate cognitive processing of a specific event. It achieves this by taking multiple readings and averaging them in order to filter out all brain activity that is not related to the appearance of the stimulus.
Scanning techniques- FMRI definition
Functional Magnetic Resonance Imaging (fMRI)
A technique for measuring brain activity. It works by detecting changes in blood oxygenation and flow that indicate increased neural activity.
Outline what post-mortem examinations are
“Ways of examining the brains of people who have shown particular psychological abnormalities prior to their death in an attempt to establish the possible neurological cause for this behaviour.”
Post-mortem examinations are used to establish the underlying neurobiology of particular behaviour.
When a person dies the researcher can examine their brain to look for abnormalities that may have explained their behaviour when they were alive.
Post-mortem studies have also made it possible to identify some of the brain structures involved in memory.
The use of post mortem studies has also been used to establish a link between psychiatric disorders and underlying brain abnormalities
Give 2 well-known example of post-mortem research
link to memory bruh
Boca’s work on his patient Tan- displayed speech problems when alive and was found to have a lesion in the area of the brain now known as ‘Broca’s Area’.
Henry Molailson (HM)- confirmed that HM’s inability to store new memories was linked to lesions in his hippocampus.
Outline the 4 basic EEG patterns and how they change as you change from light to deep sleep
There are four basic EEG patterns
Alpha waves- when a person is awake and relaxed, rhythmical waves.
Beta waves- when a person is physiologically aroused their EEG pattern shows low amplitude and fast frequency waves. Also in REM sleep.
Delta waves- during sleep.
Theta waves- during sleep.
As a person moves from light to deep sleep their alpha waves decrease, replaced by lower frequency theta waves and then delta waves.
What are ERPs and why are the difficult?
What are the different ERP categories?
Small voltage changes in the brain that are triggered by a specific event or stimulus, such as cognitive processing of a specific stimulus.
ERPs are difficult to pick out from other electrical activity.
To establish a specific response to a target requires many presentations of the stimulus, then the responses are averaged together.
Any extraneous neural activity not related to the stimulus will not occur consistently, whereas activity linked only to the stimulus will.
ERP categories
Waves within first 100 milliseconds = sensory ERPs (an initial response to a stimulus).
Waves after the first 100 milliseconds= cognitive ERPs (demonstrate information processing).
Outline what FMRIs are and how they work.
Why are they useful?
A technique for measuring brain activity while a person performs a task.
Measures the change in blood flow in particular areas of the brain, this indicates increased neural activities in those areas.
If a particular part of the brain becomes more active there is an increased demand for oxygen in that areas and the brain responds to this by increasing blood flow to deliver oxygen in red blood cells.
Researchers are able to produce maps showing which areas of the brain are involved in a particular mental activity.
