Biopsychology A01 / Definitions Flashcards
Localisation of function
Specific areas of the brain linked to specific physical and psychological functions
Lateralisation
Some physical and psychological functions are controlled by a particular hemisphere
Motor area
- frontal lobe
- controls voluntary movement
- damage results in loss of control over fine motor movements
Somatosensory area
- parietal lobe
- processes sensory info from skin
Visual area
- occipital lobe
- each eye sends info from the RVF to the LH & vice versa.
Auditory area
- temporal lobe
- analyses speech based info
- damage may produce partial hearing loss
Broca’s area
- left of frontal lobe
- linked with speech production
- damage results in Broca’s aphasia
Broca’s aphasia
- Speech is slow & lacks fluency
Wernicke’s area
- left temporal lobe
- linked with language understanding
Wernicke’s aphasia
- produce fluent but meaningless speech
- often produce nonsense words
Contralateral
- In the motor area the RH controls the left side of the body & vice versa
Brain plasticity
- During infancy the brain experiences a rapid growth in synaptic connections
- Rarely used connections deleted & frequently used connections strengthened
3 structural changes in the brain following trauma
1) Axonal sprouting
2) Denervation supersensitivity
3) Recruitment of similar areas
fMRI
- detects changes in blood oxygenation & flow
- produces 3D image showing active areas of brain
EEG
- measures electrical activity in brain using electrodes
- scan shows overall electrical activity
- often used as diagnostic tool
Circadian rhythms
- lasts for about 24 hrs
E.g sleep/wake cycle
-governed by exogenous zeitgeibers & endogenous pacemakers
2 examples of infradian rhythms
1) menstrual cycle
2) S.A.D
SAD
- depressive disorder w/ a seasonal pattern
- at night pineal gland secrets melatonin until daylight
- in winter less light = longer secretion
- this has a knock- on effect on the production of seretonin
5 stages of sleep
Stages 1 and 2
- light sleep
-alpha waves
Stages 3 and 4
- deep sleep
- waves are lower frequency
Stage 5 (REM)
- body is paralysed but brain activity resembles activity of awake brain
-theta waves
SCN
- Suprachiasmatic nucleus
- Bundle of nerves in hypothalamus
- Lies above optic chiasm & receives info about light from this structure
