Mapping the mind

Question 1

Lesion

Answer 1

Area of damage to the brain due to surgery, injury or disease

Question 2

Electroencephalography (EEG)

Answer 2

Recording of the brain’s electrical activity at the surface of the scalp. The method has a high temporal resolution, however relatively low spatial resolution.

Question 3

Computed tomography

Answer 3

A scanning technique using multiple X-rays to construct three-dimensional images

Question 4

Magnetic resonance imaging (MRI)

Answer 4

Technique that uses magnetic fields to indirectly visualise brain structure.
The MRI scanner measures the release of energy from water in biological tissues following exposure to a magnetic field. MRI images are superior to CT scans for detecting soft tissues, such as brain tumours

Question 5

Positronic Emission tomography (PET)

Answer 5

Imaging technique that measures uptake of radioactive glucose molecules, yielding a picture of regional metabolic activity in different brain regions

Question 6

Functional MRI (fMRI)

Answer 6

Technique that uses magnetic fields to visualise changes in blood oxygen levels due to brain activity.
The fMRI has a spatial resolution of just a few cubic millimetres, depending on the strength of the magnetic field. The method shows changes in brain activity level over as little as two seconds

Question 7

Transcranial magnetic stimulation (TMS)

Answer 7

Technique involving a coil that generates a magnetic field that can temporarily block or stimulate neural transmissions within a small brain area.
TMS is the only non-invasive brain-imaging technique that allows us to infer causation—all other techniques can only correlate brain activation with psychological processing

Question 8

Magnetoencephalography (MEG)

Answer 8

Measure of brain activity using magnetometers, which sense tiny magnetic fields generated by the brain and nervous system.
MEG has better spatial resolution than EEG, especially for activity deep within the brain, and retains excellent temporal resolution—measuring activity changes milli- second by millisecond—whereas PET and fMRI scans measure activity changes second by second

Question 9

Cortical synchronisation

Answer 9

Similar patterns of temporal activity across multiple brain areas, which are critical to cognition

Question 10

Lateralisation

Answer 10

Cognitive function that relies more on one side of the brain than the other

Question 11

Split-brain surgery

Answer 11

Procedure that involves severing the corpus callosum to reduce the spread of epileptic seizures

Question 12

Functions associated with left hemisphere

Answer 12

Fine-tuned language skills
- Speech comprehension 
- Speech production 
- Phonology 
- Syntax
- Reading 
- Writing
Actions
- Making facial expressions 
- Motion detection

Question 13

Functions associated with right hemisphere

Answer 13

Coarse language skills
- Simple speech 
- Simple writing 
- Tone of voice
Visuospatial skills
- Perceptual grouping 
- Face perception