Biopsychology Flashcards
Outline research on the effect of exogenous zeitgebers on the sleep/wake cycle that aren’t light
Folkard et al (1985)
- Put 12 participants in a cave for 3 weeks with a clock
- Researchers gradually increased the speed of the clock til a day passed in 22 hours
- All but one of the participants synchronised with the clock
Outline research support for circadian rhythms
Main study
Siffre
- Lived in a cave for extended periods of time on multiple occasions with no exogenous zeitgebers
- His natural circadian rhythm settled down to just over 24 hours with some dramatic variations
- As he got older, his circadian rhythms got much longer, sometimes being 48 hours long
Define the term exogenous zeitgeber
An environmental cue such as light that helps to regulate the biological clock
Define the term endogenous pacemaker
Mechanisms within the body that govern the internal biological rhythms
Name the different types of rhythms
- Circadian rhythm - 24hrs
- Infraradian rhythm - >24 hrs
- Ultraradian rhythm - <24 hrs
Outline and evaluate ERP scans
- Same as EEG but taken while doing an activity
- EEG taken at rest > EEG taken while doing activity > EEG1 taken away from EEG2 to isolate the the activity
Evaluation is the same as EEG
Outline and evaluate EEG scans
Uses electrodes on the scalp to measure the electrical activity of neurons firing. Measures general activity at rest.
Good
- High temporal resolution
- Very portable
- Relatively cheap
- Not invasive
Bad
- Low spatial resolution
- Not detailed enough to measure individual neurons, only general areas of activity
- Can only measure the outer area of the brain
Outline and evaluate fMRI scans
Brain scanning technique that measures blood flow in the brain while performing a cognitive task. Oxygenated and deoxygenated blood have different magnetic qualities. More blood going to an area = more activity
Good
- Not invasive
- High spatial resolution
- Ethical
Bad
- Very expensive
- Not portable
- Low temporal resolution
- Must stay perfectly still
Outline and evaluate Post Mortem examination
Cut up the brain after death
Good
- Allows for a more detailed examination
- Can examine deeper parts of the brain
- High spatial resolution
Bad
- Ethical issues with getting consent from a mentally ill person
- Cause and effect not provable
- Correlation ≠ causation
- Patient is dead
Name the ways of studying the brain
- Post Mortem
- fMRI
- EEG
- ERP
Outline research support for Brain Plasticity
Maguire et al (2000)
- Compared MRI scans of 16 taxi drivers to 50 controls
- The taxi drivers had significantly more volume in their posterior hippocampus than the control group
- There was also a positive correlation between posterior hippocampus volume and time worked as a taxi driver
List and define the Mechanisms of Recovery
- Axon sprouting - Neurons may sprout axons in order to form new neural pathways
- Neuronal unmasking - Dormant neural pathways which were previously unused may become activated in order to compensate for the damaged brain areas
- Neural reorganisation - An intact brain area may completely take over the function of the damaged area
Define Functional Recovery
A form of plasticity following trauma where the healthy parts of the brain may require to take over the functions of the damaged area
Define Brain Plasticity
- The idea that our brain is able to change throughout our life
- New connections can be formed and old ones removed
Outline research support for brain plasticity
Case study
Thaler et al (2011)
- Examined two blind people that could echolocate
- Proved that they could echolocate by asking them to give the angle of a pole in the ground, they gave very accurate answers
- fMRIs showed that the processing of the click echoes occurred in the visual cortex instead of the auditory cortex
- Shows that the visual cortex has rewired itself to allow for echolocation
Outline research that disputes hemispheric lateralisation
Patient JW (Gazzaniga et al 1996)
- Patient JW is a split brain patient who seems to have developed right-hemisphere speech capabilities
- He could verbally name an object presented to the LVF
- He performed badly on interfield tasks, ruling out the possibility that his hemispheres are communicating
Outline Split-Brain research
Sperry (1968)
- Conducted research on 11 patients who had their corpus callosum severed and compared to 11 healthy controls
Description task
- Patients asked to verbally name objects presented to either the LVF or RVF
- Objects in the LVF could not be named but objects in the RVF could
- Suggests that language production centres are in the left hemisphere
Drawing task
- Patients asked to draw objects flashed to either visual field with different hands
- Patients drew better with their left hand even when they were right handed
- Suggests that the right hemisphere is specialised for drawing
Matching Faces task
- Patients shown faces to each visual field and asked to identify the faces from a line up
- Patients consistently identified the face from the LVF
- If a split face was shown, patients would identify the face in the LVF and verbally describe the face in the RVF
- Suggests that the right hemisphere is specialised for facial recognition
Outline research that disputes localisation of function
Lashley (1950)
- Removed parts of rats’ brains randomly while they were learning a maze (10% - 50% of the brain removed)
- The more brain he removed the worse they did at the maze but it didn’t matter which parts were removed
- Equipotentiality Theory
What is Equipotentiality Theory
Higher brain functions are not localised, the brain works together to carry out tasks
Outline research support for Broca’s Area
Patient ‘Tan’ (Broca’s aphasia)
- Patient could only said the word ‘Tan’ but could comprehend speech
- Large lesion in Broca’s area found in post mortem
Outline research support for localisation of function
Case study
Phineas Gage (1848)
- Steel rod went through his skull in a work accident causing damage to his frontal lobe
- He became aggressive and showed a lack of inhibition
- Shows that frontal lobe is responsible for behavioural control and personality
Outline research support for localisation of function
Neuroimaging Research
Desposito et al (2014)
- Meta analysis of neuroimaging research associated:
- Central executive - Frontal lobe
- Phonological loop - Temporal lobe
- Visuospatial sketchpad - Occipital lobe
Outline the function of Wernike’s Area
- Speech comprehension
- In the left hemisphere
Outline the function of Broca’s Area
- Speech production
- Only in the left hemisphere
