TMS

Question 1

What is Phineas Cage associated with?

Answer 1

American railroad construction worker, who suffered a serious injury by an iron rod piercing his head and frontal cortex. This led to severe changes in his personality.

Question 2

In TMS, what does the coil produce?

Answer 2

A magnetic field

‘a rapidly changing magnetic field’

Question 3

What were Fritsch & Hitzig (1870) known for?

Answer 3

Electrically stimulating the cortex of animals

Question 4

What was D’Arsonval (1896) known for?

Answer 4

Discovering that the magnetic stimulation of the visual cortex can elicit “phosphenes”

Question 5

What was Magnusson & Stevens (1911) known for?

Answer 5

Developing the ‘head coil’ version of TMS

Question 6

Who developed the current TNS technique? (hint: 3 guys, awkward photo, 1985)

Answer 6

Barker, Jalinous & Freestone (1985)

Question 7

What were Barker, Jalinous & Freestone (1985) known for?

Answer 7

The guys who developed the current TMS technique

Question 8

What is the advantage of using a figure-8 shaped coil for TMS?

Answer 8

More precision

(The figure-eight coil generates magnetic fields in the opposite direction, thereby generating offset current loops that circulate in opposite directions, allowing for more precision)

Question 9

When using a figure-8 coil for TMS, what is the radius of the ‘strongest effect’ bit in the brain?

Answer 9

3-4mm

Question 10

Name the four modes of using TMS that Stefan discussed?

Answer 10

1. Neural noise
2. Virtual lesion
3. Probing excitability
4. Paired-pulse approach

Question 11

What actually is the ‘neural noise’ TMS approach?

Answer 11

A single pulse is injected to disrupt cognitive processing

Question 12

What is the ‘neural noise’ TMS approach good for testing?

Answer 12

Causality!

Question 13

What is Amassian (1989, 1993) known for ?

Answer 13

Doing two classical ‘neural noise’ TMS studies.

(1989) looked at letter perception, and specifically at the time at which the visual cortex processed visual information
(1993) Looked at whether a visual mask can itself be masked(?)

Question 14

What actually is the ‘virtual lesion’ TMS approach?

Answer 14

Inhibiting cognitive function for a longer period by applying repetitive TMS (rTMS).

You then measure whether (and how long) a specific cognitive task is impaired

Question 15

What actually is the ‘probing excitability’ TMS approach?

Answer 15

Instead of aiming at disrupting cognitive functions (and measuring the effect of TMS on performance), the measure of interest is how strongly the motor cortex “reacts” to the TMS pulse itself.

Question 16

What is the metric used to measure cortical excitability during the ‘probing excitability’ TMS approach?

Answer 16

Motor evoked potential (MEPs)

Question 17

What device do you use to measure MEPs?

Answer 17

An electromyogram (EMG)

Question 18

What actually is the ‘paired pulse’ TMS approach?

Answer 18

It uses two pulses, delivered in brief succession – one is usually sub-threshold while the second one is supra-threshold.

The question is how strongly the first pulse influences the effect of the second

Question 19

TMS has not yet been formally endorsed as a treatment option for depression, T/F

Answer 19

FALSE

The Royal Australian & New Zealand College of Psychiatrists (position statement 79, October 2013) has endorsed TMS as a treatment option for depression.