L9 - Techniques

Question 1

Temporal resolution

Answer 1

the precision of measurement of brain activity in time

Question 2

Spatial

Answer 2

the precision of measurement of brain activity with respect to space

Question 3

Invasiveness

Answer 3

the degree to which the brain is directly and physically affected

Question 4

Macroscopic

Answer 4

visible to the naked eye

meters & centimeters

Question 5

Mesoscopic

Answer 5

On a scale between microscopic and macroscopic

millimetres

Question 6

Microscopic

Answer 6

so small as to be visible only with a microscope

micrometers & nanometers

Question 7

The scientific method

Answer 7

~ observations (data)
~ explanation of model/theory
~ predictions
~ experiment
~ repeat

Question 8

Active experimental conditions

Answer 8

subject performs a cognitive task while brain activity is being measured
e.g. detection

Question 9

Passive experimental conditions

Answer 9

subject sits passively and performs no task

e.g. sleep

Question 10

Use of lesions

Answer 10

~ to localise different brain functions
~ dame to brain = cognitive impairment
LIMITATION: other areas may also be vital for function in question

Question 11

Name imprecise origins of lesions

Answer 11

Degenerative disease
stroke
traumatic brain injury
~ poor spatial resolution

Question 12

Name precise origins of lesions

Answer 12

artificial legions
temporal legions (cooling techniques)
~ good spatial resolution

Question 13

Single dissociation

Answer 13

~ test for impairment on task with damage to one brain region e.g. temporal
~ compare to controls

Question 14

Double dissociation

Answer 14

~ test for impairment on task on patients with different types of brain damage e.g. temporal and frontal lobe
~ compare to controls

Question 15

Name four methods of invasive perturbations

Answer 15

(invasive brain interruptions)
cooling
pharmacology
electrical stimulation
optogenetics

Question 16

Cooling

Answer 16

~ deactivates brain regions
~ specially precise
~ fully reversible
~ animals can be their own controls (much better than separate control group)

Question 17

Pharmacology

Answer 17

~ psychoactive substances cross the blood brain barrier + act on synaptic transmission
~ can be agonist or antagonist

Question 18

Electrical stimulation

Answer 18

~ implantation of electrode via neurosurgery
~ stimulate neural activity
~ deep-brain stimulation in basal ganglia alleviates Parkinson’s disease

Question 19

Optogenetics

Answer 19

~ genetic modification allows expression of protein (ChR-2) which forms light-gated ion channels
~ action potentials can be turned on and off with light
~ behaviour changes = possibility of clinical applications

Question 20

Lesion studios pros

Answer 20

~ unequivocal evidence that damaged area participates in certain cognitive function
~ artificial ablations are precise

Question 21

Lesion studies cons

Answer 21

~ spatially imprecise when cause by injury or disease

~ LIMITED - does not reveal fully how or where function takes place, only shows necessary parts not all parts involved

Question 22

Invasive perturbations pros

Answer 22

~ excellent spacial and temporal resolution (electrical stimulation. & optogenetics)
~ subjects are their own controls
~ clinical applications

Question 23

Invasive perturbations cons

Answer 23

~ poor resolution (pharmacology)

~ invasiveness - risk of infection + discomfort