Neuroimaging techniques

Question 1

contrast x-rays

Answer 1

injecting substance that absorbs x-rays compared to surrounding tissue

Question 2

x-ray computed tomography

Answer 2

computed x-ray to view brain and other intended structures

Question 3

magnetic resonance imaging (MRI)

Answer 3

high spatial resolution (just brain structure)
2D or 3D

measures waves of hydrogen atoms when electrically stimulated
energy via radiofrequency
energy is absorbed and emitted differently by different tissues (gives information on structure)

Question 4

positron emission tomography (PET)

Answer 4

brain activity - not structure!
uses a similar substance to glucose that cant be metabolised
radiation higher in active regions (gamma rays)
biological processes
uses radiation so it has a limited use

Question 5

functional MRI (fMRI)

Answer 5

oxygen flow in the brain
3D images
good spatial resolution
oxygenation of the of blood in the tissue (active brain regions call up more blood)

Question 6

diffusion tensor imaging (DTI)

Answer 6

method of identifying which water molecules diffuse

= images of tracts

Question 7

transcranial magnetic stimulation

Answer 7

tried to establish a causal effect by temporarily lesioning areas

can also activate areas - inducting action potential reactions

Question 8

recording psychophysiological activity (EEG)

Answer 8

EEG - measures gross electrical activity of the brain (action potentials, post synaptic potentials, electrical signals from skin)
- signal averaging - avoids background noise = average evoked potentials (ARPs)

+ temporal
- spatial

Question 9

recording psychophysiological activity (MEG)

Answer 9

magnetoencephalogrophy - changes in magnetic field produce by changed in neural activity

+ better spatial resolution

Question 10

recording psychophysiological activity (muscle tension)

Answer 10

anxious/nervous people = higher levels of tension

recorded with electromyagram (EMG)

Question 11

recording psychophysiological activity (eye movement)

Answer 11

difference in potential between front an back of the eye (changes in electric potential when it moves)

Question 12

recording psychophysiological activity (skin conductance)

Answer 12

skin conductance response (higher when aroused)

Question 13

recording psychophysiological activity (cardiovascular activity)

Answer 13

heart rate, blood pressure, blood volume (genitals)

Question 14

stereotaxic surgery

Answer 14

experimental device placed in the brain (invasive)

need:
stereotaxic atlas and stereotaxic instrument

Question 15

aspiration lesions

Answer 15

can see where you are lesioning

sucking away cortex so white matter underneath can be stuied

Question 16

radio-frequency lesions

Answer 16

current through target tissue - heat destroys

Question 17

knife cuts

Answer 17

nerve or tracts

Question 18

reversible lesions

Answer 18

cooling or anaesthetising (same p tested more than once)

Question 19

interpretation

Answer 19

hard as you usually damage other areas of the brain

Question 20

intragastricaly

Answer 20

tube into the stomach

Question 21

intraperitonealy

Answer 21

abdoman

Question 22

intramuscularly

Answer 22

large muscle

Question 23

subcutaneously

Answer 23

beneath the skin

Question 24

intravenously

Answer 24

surge surface vein

Question 25

selective chemical lesions

Answer 25

injecting neurotoxins - certain affinity for NS | Ibotenic acid and Kainic acid - taken up by cell bodies

Question 26

2-deoxyglucose technique (2-DG)

Answer 26

measuring chemical activity in the brain | injecting substance similar to glucose so highlights active regions

Question 27

cerebral dialysis

Answer 27

measures extracellular concentration of specific neurochemicals small semi-permeable tube placed in the brain

Question 28

immunocyto chemistry

Answer 28

immune reaction | foreign chemical is injected into the body creating antibodies

Question 29

in situ hybridisation

Answer 29

locating peptides and other proteins in the brain

Question 30

gene knockout technique

Answer 30

creating organisms that lack a particular gene

Question 31

gene replacement techniques

Answer 31

pathological human cells can replace cells of other animals

Question 32

GFP

Answer 32

green florescent protein - elicits a green light when expose to blue light insert into target cells brainbow - other colours can be used

Question 33

single test approach

Answer 33

no single test could be developed to distinguish between structure and function

Question 34

standard test-battery approach

Answer 34

sets of tests to identify brain damaged patients | Halstead-Reitan neurophysiological test battery - set of tests performed poorly by brain damaged patients

Question 35

customise test battery approach

Answer 35

identifies and characterises brain damaged patients begins with broad tests and becomes narrower

Question 36

tests of the common neurophysiological test battery

Answer 36

IQ - Wechsler adult intelligence scale (WAIS) [15 subtests that show area of dysfunction] Memory - WAIS - often fails to detect memory deficits but usually this is described by the patient on arrival Language - token test - different shapes, colours and sizes - told to organise in a more and more challenging way language lateralisation - sodium amytal test and dichotic listening test - left side of brain usually more influential

Question 37

tests of specific neuropsychological function

Answer 37

memory - is it LTM or STM - LTM - anterograde (after damage) or retrograde (before damage) - semantic or episodic? - explicit or implicit? repetition priming tests = amnesic patients as good as normal but don't remember seeing words language - deficits in (a) phonology, (b) syntax or (c) semantics

Question 38

frontal lobe function

Answer 38

Wisconsin card sorting test - patient is told to sort cards but not how - begin guessing and told whether or not they're right or wrong - researchers change the way you sort - those with frontal damage cant change the way they sort them

Question 39

paired image subtraction technique

Answer 39

brain images of lots of tasks, estimate activity by subtracting normal from active brain at rest = default mode brain structures active during task are less active during rest mode = default mode network

Question 40

tests of aggressive and defensive behaviour

Answer 40

intruder paradigm | elevate plus maze

Question 41

pavlovian conditioning

Answer 41

pairing neutral stimulus with an unconditional stimulus, that elicits an unconditional response

Question 42

operant conditioning

Answer 42

rate at which a voluntary response in increased by reinforcement or decreased by punishment - self stimulation paradigm (pleasure centres in the brain excited)

Question 43

conditional taste aversion

Answer 43

avoidance response that develops to tastes of food following illness

Question 44

neophobic

Answer 44

scare of new things

Question 45

marris water maze

Answer 45

tests spatial awareness in rats

Question 46

radial arm maze

Answer 46

spatial abilities in rats