Behavioural neurosciences Flashcards
List neuroimaging techniques to assess structural measures
and describe 3 in details
MRI, CT, cerebral angiography, X rays, promesencephalography
–MRI- Coronal, horizontal saggital
Giant circular magnet creates strong magnetic field, aligns H+ in tissues, Radio frequency coil produces radio wave pulses, protons spin and tilt
Signal detected by a receiver- gives an image
–VBM- detects size of different brain areas eg caudate smaller in tourettes, larger in athletes
–Diffusion MRI- white matter tracts. Myelin stops free movement of H20. With age, tracts increase in thickness, frontal tract increases in development
List and describe 4 techniques to measure brain function
PET, fMRI, EEG, ERP
- PET- measure O2 consumption- labelled O2 water injection, emit positrons, detected by gamma ray detectors - EXPENSIVE- radioactive isotopes
- fMRI- indirectly measure brain activity- changes in cerebral blood flow during cognitive tasks- slow, changes in flow take a while
changes in deoxy/oxyHb- high metabolic activity- oxy decreases. Used in Tourettes- dampen motor response. smaller signal in control tics- poor time resolution, noise, claustrophobia, indirect
- EEG continuous recording of brain activity- scalp electrodes during tasks. Small measurement from neurones- indirect measurement, signal post synaptic not AP
don’t Need high activity level, sleep studies, anaesthesia, epilepsy
- ERP- event related potentials- evoked electrical activity- sensory motor cognitive efects
Need repeats, coarse spatial resolution, modelling of dipoles
good time resolution, exact timing, non invasive, cheap
Define neuropsychology
Study of relationship between brain, mental life and behaviour
Study behaviour and cognitive mechanisms in healthy and undamaged brain
Cognitive defects after injury, insult and neurodegeneration
List and define the two main types if neuropsychology?
Experimental- Applying research methods of experimental/cognitive psychology in order to better understand behavioural and cognitive process in healthy and/or damaged brain
Clinical- applying NP in clinical setting, assess damage using a psych, neuro and physio tests- help develop a treatment plan
Describe split brain
Corpus callosam
R side see objects, L side name. Can’t see objects on left side. Also removed in severe epilepsy
Describe patient HM
Hippocampi removed
Loss of episodic memory, procedural memory unaffected. Disassociation between different memory types
Describe Phineas Gage
Damage to orbitofrontal cortex- change in behaviour and personality and socioemotional decision making
Describe dysexecutive syndrome
and outline 5 causes
Damage to dorsolateral prefrontal cortex- memory, attention, planning, organisation
- Trauma- open/closed head injury
- Infection- HIV, herpes simplex
- Neurodegen disorders- Parkinson’s, Alzheimer’s, Huntington’s, Pick’s, MS
- Cerebral vascular disease- stroke, ischaemia, high BP, aneurysm
- Intracranial tumours- glioma, meningioma, adenomas, metastatic tumours
Define single case studies
Insight into functional component of cognition
Region of lesion- impairment of specific semantic categories
- comprehensively document performance
Define group case studies
Defined according to common neurodiagnosis/damage. Same region- similarities?
Major problem- lack of homogenity due to variability of patients- age, gender motivation, diff
Define a single disassociation and double disassociations
A single dissociation is when a manipulation leaves one cognitive function (say, A) intact whilst severing another (say, B).
This indicates the functions A and B are at least partially independent. A double dissociation is when there exists, in addition, a manipulation that does the reverse (i.e. leave B intact whilst severing A).
Describe problems with single disassociation
2 tasks differ in difficulty/sensitivity to component process they test
Gives rise to disrupt or intact profile
Describe Broca’s and Wernicke’s as an example of double disassociation
Broca’s- inability to be fluent, can comprehend speech- while Wernicke’s aphasia can’t comprehend speech
