Lecture 5 - Modularity Flashcards
Describe the case of Phineas Gage (1823-1860)
Phineas Gage (1823-1860)
- In 1848 had an accident while laying a railroad in Vermont.
- This changed his personality.
Contemporary account:
- …He is fitful, irreverent, indulging at times in the grossest profanity (which was not previously his custom)…
What are 4 different methods of explorations of the brain.
- Behaviourism
- Psychophysics
- Neuroanatomy
- Neuroscience
List 5 ways in which you can assess a patient with cognitive impairment.
- Anatomical brain scan (CT or MRI)
- Interviews and behavioural assessment
- Normal psychometric tests
- Standardised neuropsychological tests
- Unstandardised tests
Information about a patients deficits can be obtained by asking the patient or those close to the patient.
Tests such as IQ tests allow for comparison with a large sample of what is considered normal data. May reveal a general deficit in abilities. These are not designed to tell us about particular cognitive deficits.
Standardised test are validated as measure of selective cognitive impairment.
List 4 standardised neuropsychological tests.
Describe 2.
- Wechsler Adult Intelligence Scale WAIS
(see relevant powerpoint, slide 12 for diagram) - Wisconsin card sorting
- National Adult Reading Test > Measure of ‘pre-morbid’ IQ > Tests pronunciation of words * Depot, Simile, Heir, Recipe * Prelate, Syncope, Topiary, Superfluous * Synecdoche, Cidevant Si Nec Do Kee (part is used to refer to whole) Seed Evon (former)
- Behavioural Inattention Test
What is a standardised test?
- Clear coding system
- Compare with published norms.
What is an unstandardised test?
- Able to probe individual problems of a particular case.
- Absence of extensive age-matched controls.
- Controls can be established afterwards.
Define the condition Agnosia.
Neuropsychological condition.
Agnosia -
Loss of ability to recognise.
Define the condition Prosopagnosia.
Neuropsychological condition.
Prosopagnosia -
Loss of ability to recognise faces.
Define the condition Alexia.
Neuropsychological condition.
Alexia -
Loss of ability to recognise test.
Define the condition Time agnosia.
Neuropsychological condition.
Time agnosia -
Loss of ability to order events.
Define the condition Aphasia.
Neuropsychological condition.
Aphasia -
Many types of communication difficulties.
Define the condition Unilateral neglect.
Neuropsychological condition.
Unilateral neglect -
Failing to attend to one side.
Describe:
- Associations
- Dissociations
- Double dissociations
(see relevant powerpoint, slides 19-23)
List 3 other methods to investigate brain function.
Describe them.
- fMRI
Functional magnetic resonance
imaging
> Measures blood oxygen levels in the brain as an indicator of regional activity (BOLD)
> High spatial resolution (voxels of less than 1mm)
> Records in 3D (ie, internal brain activity)
Disadvantages
> Indirect measure of brain activity
> Slow responses (2-5s) makes temporal resolution poor - MEG/EEG
Magnetoencephalography
Electroencephalography
> Measurement of electrical action potentials at the scalp to infer synaptic activity.
> High temporal resolution (better than 1ms)
Disadvantages
> Poorer spatial localisation - TMS
Transcranial magnetic stimulation
> The use of powerful magnets to stimulate parts of the brain.
> Knock out technique – virtual lesion
What are event related potentials? (ERPs)
- Take a particular event and measure the pattern of potentials following it.
- Repeat many times.
- Find the average pattern for a particular type of event.