Section 3 - Quantifying Cogntion; Neuropsychology, Neuroimaging & Neuromodulation

Question 1

What’s Unilateral Neglect?

Answer 1

When patients have impaired attention to the side contra-lateral to their lesion

Question 2

Posner & Cohen (1984)

Answer 2

Exogenolis orienting - occurs when attention is guided by goals of the perceiver

Question 3

What’s Spotlight Theory of Attention?

Answer 3

impaired disengagment

Question 4

What’s the Biased Competition Model?

Answer 4

A consequence of attention orientating to the ipsilesional side

Question 5

What’s the Extension disorder of attention?

Answer 5

When bloody supply around the Arteria cerebra median are often affected due to posterior parietal injury

Question 6

What’s Perceptual Grouping (Reducing method of extinction)?

Answer 6

Process of determining which regions & parts of the visual scene belong together as parts of higher order perceptual units such as objects/patterns.

Question 7

What’s Spotlight Metaphor of Attention?

Answer 7

Disengage -> move -> engage

Question 8

What’s Premotor Theory of Attention?

Answer 8

Consequence of activation of the motor system, shifts pf attention are by goal-directed actions

Question 9

What’s TES?

Answer 9

Refers to techniques that involve passing weak currents through the skull for the purposing of stimulating the brain

Question 10

tDCS (direct)

Answer 10

Current of fixed magnitude is passed from one electrode to another

Question 11

tACS (alternating)

Answer 11

Strength of current is varied at a particular frequency

Question 12

o-tDCS (oscillatory)

Answer 12

Current ranges from 0-2 at the anode & -0 - -2 at the cathode

Question 13

tRNS(transcranil random noise)

Answer 13

Intensity is varied randomly over time rather than constant or varying at a set frequency

Question 14

What are the results of TES?

Answer 14

Neurones become more/less likely to fire, doesn’t trigger action potential and prolongs stimulation overtime

Question 15

EPSP

Answer 15

An active presynaptic cell releases neurotransmitters into the synapse. Some bind to the receptors on the postsynaptic cell. Ion channels activated. Post synaptic excitation or inhibition

Question 16

Association

Answer 16

Damage to single brain region = multiple deficits

Question 17

Dissociation

Answer 17

Damage = impaired performance in task A but B is normal

Question 18

What is Electrocephalography?

Answer 18

It measures the electrical brain activity at the post synaptic potentials by large populations of the neurones firing together. (must be spatially aligned)

Question 19

What’s Cognitive Neuroscience?

Answer 19

Understanding the biological basis of consciousness & the mental processes by which we perceive, act, learn and remember

Question 20

What are the 5 experimental disciplines that cognitive neuroscience emerged from?

Answer 20

Anatomy, embryology, physiology, pharmacology and psychology

Question 21

H.M

Answer 21

Lesions, 1953. Had a surgical resection of medical temporal lobes (removed hippocampus) which resulted in anterograde amnesia

Question 22

What does a PET do?

Answer 22

Detects a ‘tracer’ that’s introduced onto the body on a biologically active molecule. The concentrations of the tracer give the metabolic activity

Question 23

What are the pros of a PET?

Answer 23

Excellent spatial resolution

Question 24

What are the cons of a PET?

Answer 24

Poor temporal resolution, radiation exposure, very expensive

Question 25

What does a TMS do?

Answer 25

Can either excite cortex or temporally disturb cortical features

Question 26

What are the pros of a TMS?

Answer 26

Virtual lesion may be better defined, reduces plasticity, temporal resolution in millisecond range

Question 27

What are the cons of TMS?

Answer 27

Discomfort, only one area, requires anatomical images, difficult to model path of current

Question 28

What are the cons of FmRI

Answer 28

Poor temporal resolution, no movement, noise, confined space and expensive

Question 29

What are the pros of FmRI?

Answer 29

Excellent spatial resolution, all brain accessible, measures change, no radiation exposure

Question 30

What is a FmRI?

Answer 30

Looks at the Blood Oxygen Level Dependent EFFECT = Basics of a functional MRimaging

Question 31

What’s a structured MRI?

Answer 31

Provides a high resolution structural image, high contrast between soft tissues, no exposure to radiation, high fixed strength magnets

Question 32

What’s the Haemodynamic Response?

Answer 32

When active neurones use energy the blood releases oxygen to activate neurones which causes a change of the relative levels of oxyhemoglobin & deoxyhemoglobin. This then have different magnetic properties.