The imaged brain

Question 1

Structural imaging

Answer 1

Measures of the spatial configuration of different types of tissue in the brain (principally CT and MRI).

Question 2

Functional imaging

Answer 2

Measures temporary changes in the brain physiology associated with cognitive processing; the most common method is fMRI and is based on hemodynamic measure.

Question 3

Voxel-based morphometry (VBM)

Answer 3

A technique for segregating and measuring differences in white matter and gray matter concentration.

Question 4

Diffusion tensor imaging (DTI)

Answer 4

Uses MRI to measure white matter connectivity between brain regions.

Question 5

Voxel

Answer 5

A volume-based unit (cf. pixels, which are 2D); in imaging research the brain is divided into many thousands of these.

Question 6

Fractional anisotropy (FA)

Answer 6

A measure of the extent to which diffusion takes place in some directions more than others.

Question 7

BOLD

Answer 7

Blood oxygen-level-dependent contrast; the signal measured in fMRI that relates to the concentration of deoxyhemoglobin in the blood.

Question 8

Hemodynamic response function (HRF)

Answer 8

Changes in the BOLD signal over time.

Question 9

Cognitive subtraction

Answer 9

A type of experimental design in functional imaging in which activity in a control task is subtracted from activity in an experimental task.

Question 10

Pure insertion (also pure deletion)

Answer 10

The assumption that adding a different component to a task does not change the operation of other components.

Question 11

Interactions

Answer 11

The effect of one variable upon another.

Question 12

Efference copy

Answer 12

A motor signal used to predict sensory consequences of an action.

Question 13

Functional integration

Answer 13

The way in which different regions communicate with each other.

Question 14

Resting state paradigm

Answer 14

A technique for measuring functional connectivity in which correlations between several regions (networks) are assessed while the participant is not performing any tasks.

Question 15

Default mode network

Answer 15

A set of brain regions that is more hemodynamically active during rest than during tasks.

Question 16

Stereotactic normalization

Answer 16

The mapping of individual differences in brain anatomy onto a standard template.

Question 17

Smoothing

Answer 17

Redistributing brain activity from neighbouring voxels to enhance the signal-to-noise ratio.

Question 18

Talairach coordinates

Answer 18

Locations in the brain defined relative to the atlas of Talairach and Tournoux.

Question 19

Famil Wise Error (FWE)

Answer 19

An approach for correcting for many statistical comparisons based on the number of tests being conducted.

Question 20

False Discovery Rate (FDR)

Answer 20

An approach for correcting for many statistical comparisons based on the number of positive results obtained.

Question 21

Inhibition

Answer 21

A reduction/suppression of the activity of a brain region (or a cognitive process), triggered by activity in another region/process.

Question 22

Excitation

Answer 22

An increase of the activity of a brain region (or a cognitive process) triggered by activity in another region/process.

Question 23

Activation

Answer 23

An increase in physiological processing in one condition relative to some other condition(s).

Question 24

Deactivation

Answer 24

A decrease in physiological processing in one condition relative to some other condition(s).

Question 25

Semantic dementia

Answer 25

A progressive loss of information from semantic memory.

Question 26

Semantic memory

Answer 26

Conceptually based knowledge about the world, including knowledge of people, places, the meaning of objects and words.

Question 27

Multi-voxel pattern analysis (MVPA)

Answer 27

An fMRI analysis method in which distributed patterns of activity are linked to cognitive processes

Question 28

Vegetative state

Answer 28

A disorder of consciousness in which patients with severe brain damage are in a state of partial arousal.