Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BBB > Unit 5 - Brain Stimulation Methods > Flashcards

Unit 5 - Brain Stimulation Methods Flashcards

1
Q

What is noninvasive brain stimulation (NIBS)?

A

A name for a variety of methods that stimulate the brain noninvasively (from outside the skull), including by magnetic electrical and ultrasound methods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is Transcranial Magnetic Stimulation (TMS)?

A

A noninvasive stimulation of the brain caused by magnetic induction from a rapidly changing electrical current in a coil held over the scalp.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is Transcranial Electric Stimulation (tES)?

A

A noninvasive stimulation of the brain caused by passing a weak (direct or alternative - tDCS vs tACS) electrical current through it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How can brain damage be acquired - Six Ways:

A

Neurosurgery (operationally removing part of the brain)
Strokes
Traumatic head injuries
Tumours
Viral infections, e.g., HIV
Neurodegenerative disorders,
e.g., Alzheimer, Parkinson’s, Huntington’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does split brain refer to?

A

A surgical procedure in which fibres of the corpus callosum are severed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are strokes? What are they also called?

A

Disruptions in the blood supply to the brain that can lead to the death of neurons

Cerebrovascular accidents (CVA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is an aneurysm?

A

An over-elastic region of an artery that is prone to rupture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the difference between “open” and “closed” traumatic head injuries?

A

Open head injuries are usually more localised, whereas closed head injuries have more widespread effects and often produce loss of consciousness.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the difference between a strong and a classical single dissociation?

A

A strong single dissociation means that the patient is impaired on both tasks, but more so on task A.

A classical single dissociation means that a patient is impaired only on task A, and performs completely normally on task B.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a task-resource artefact? What could this imply regarding single dissociations?

A

The idea that if two tasks share the same neural/cognitive resource but one task uses it more, then damage to this resource will affect one task more than the other.

That two tasks with a single dissociation do not use different cognitive processes with different neural resources, but rather that the more impaired task simply needs more of this specific resource and consequently shows more impairment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a single dissociation?

A

A situation in which a patient is impaired in a task, A, but relatively spared on another task, B.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are double dissociations? What can they be helpful for?

A

Two single dissociations that have a complementary profile of abilities.

Discounting a task-resource artefact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a task-demand artefact? What could this imply regarding single dissociations?

A

The idea that one task is performed worse than another because the task is performed suboptimally, but not because some aspect of the task is compromised.

That the single dissociation occurs because a patient performs one of the tasks in suboptimal circumstances, e.g., they may have misunderstood the instructions or adopted an unusual strategy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What must be done to task-resource and task-demand artefacts to prove that two or more tasks have different cognitive/neural resources?

A

They must both be disproved for the exact case.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is dysgraphia?

A

Difficulties in spelling and writing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a syndrome? What can they be used for?

A

A cluster of different symptoms that are believed to be related in some meaningful way

To identify related cognitive impairments that can suggest underlying mechanisms or brain regions involved

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is classical neuropsychology and what type of studies does it favour?

A

Attempts to infer the function of a given brain region by taking patients with lesions to that region and examining their pattern of impaired and spared abilities.

Favours group studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the cognitive neuropsychology approach and what types of studies does it favour?

A

Uses the pattern of spared and impaired abilities in and of themselves to infer the building blocks of cognition, regardless of where they are located in the brain.

Favours single-case studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are group studies?

A

The performance of a group of different patients being combined to yield a group average

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are single-case studies?

A

The data from different patients is not combined

16
Q

What does “edema” refer to? What can be some of its consequences?

A

A swelling of the brain following an injury

Distorting of the true size and shape of the brain; Rendering of certain neurons inoperative even if they are not destroyed

16
Q

What are Caramazza’s assumptions for theorising in cognitive neuropsychology?

A

Fractionation Assumption:
-Brain damage can cause selective
cognitive deficits.
-Specific functions can be impaired
independently.

Transparency Assumption:
-Lesions affect existing cognitive
components.
-No new cognitive systems are
created by lesions.

Universality Assumption:
-All cognitive systems are
fundamentally identical.
-Insights from brain-damaged
individuals apply to all humans.

17
Q

What is a critique of the fractionation assumption?

A

Cognitive impairments depend on the brain’s neural architecture.

Neural circuit differences can affect detection of specific deficits.

18
Q

When is it easier to disprove the transparency assumption?

A

When the brain damage was acquired during childhood or in the development years

19
Q

Two main and current caveats / complications in neuropsychology?

A

The ability of structural imaging techniques to identify lesions

The risk of inferences drawn from lesion-deficit associations lapsing back into something similar to phrenology

19
Q

Why may group studies not be a good idea for brain-damaged patients?

A

Brain-damaged patients may have different cognitive lesions which cannot be known a priori, and thus averaging may not bring true results.

20
Q

Three ways of grouping patients for group studies?

A

Grouping by syndrome -
grouping patients which possess the same cluster of different symptoms

Grouping by cognitive symptom - grouping patients on the basis of possessing one particular symptoms

Grouping by anatomical lesion - grouping patients based of having a lesion to a particular anatomical region

21
Q

Four Methods for Producing Experimental Lesions in Animals:

A

Aspiration - aspirating brain regions using a suction device and applying a strong current at the end of an electrode tip to seal the wound
Transection - cutting discrete white matter bundles such as the corpus callosum or the fornix

Neurochemical lesions - certain toxins are taken up by selective neurotransmitter systems and once inside the cell they create chemical reactions that kill it

Reversible lesions - pharmacological manipulations used to produce reversible functional lesions, e.g., cooling parts of the brain temporarily

22
Q

What is diaschisis? When can this take place?

A

The ability of a discrete brain lesion disrupting the functioning of distant brain regions that are structurally intact

When the two regions work together as a network to implement a particular cognitive function

23
Q

What is behavioural neuroscience?

A

Cognitive neuroscience in non-human minds

24
Q

How does TMS work?

A

A change in electric current in a stimulating coil generates a magnetic field.
This magnetic field induces a secondary electric current in the neurons below the stimulation site, causing them to fire.

24
Q

What can repeated stimulation by TMS cause?

A

Longer aftereffects in which synaptic transmission is temporarily affected in that region.

25
Q

What are the two TMS protocols?

A

Online: single pulse or short train of pulses of TMS delivered around the same time as the stimulus

Offline: TMS delivered repeatedly before a task so its aftereffects influence cognition

26
Q

How can TMS be used to study functional specialisation?

A

TMS over certain areas impairing certain cognitive functions

27
Q

What is a virtual/reversible lesion? How is interference related to this?

A

When neurons involved in a critical cognitive function are stimulated by TMS, it disrupts that function.

Interference occurs because neurons are activated both by the task and the external TMS, disrupting task performance.

28
Q

How can TMS be used to study functional integration?

A

TMS over certain areas that compete with an area involved in a the current task may lead to better performance on the task

29
Q

What are the three main considerations when using TMS?

A

When to deliver the pulses

Where to deliver the pulses

Selection of appropriate control conditions

30
Q

What are the three methods of Transcranial Electrical Stimulation (tES)?

A

Transcranial direct current stimulation

Transcranial alternating current stimulation

Transcranial random noise stimulation

30
Q

What is frameless stereotaxy?

A

Use structural or functional MRI to locate candidate regions for stimulation.

Consider individual differences in brain anatomy and skull shape.

30
Q

What is task control?

A

Stimulating the same region at the same times, but with some aspect of the task changed

31
Q

What is transcranial direct current stimulation? In how many directions does the current flow?

A

A noninvasive stimulation of the brain caused by passing a weak electrical current through it

One direction

32
Q

What is the difference between immediate and aftereffects in tDCS?

A

Immediate Effects:
-Changes in excitability during the
stimulation period.
-Occur on the resting membrane
potential, not at the synapse.

Aftereffects:
-Result from changes in synaptic
strength over time due to activity.
-Influence learning and affect
different neurotransmitter systems.

33
Q

What are two types of transcranial direct current stimulation?

A

Cathodal tDCS - decreases neural excitability and decreases performance in the targeted brain region by affecting the GABA system

tDCS - increases neural excitability and increases performance in the targeted brain region by affecting the glutamate system

34
Q

What is transcranial random noise stimulation (tRNS)? How does its direction change?

A

A noninvasive stimulation of the brain caused by passing a weak electrical current through it, which fluctuates in direction and amplitude randomly

Current randomly changes in direction

35
Q

What is transcranial alternating current stimulation? In which directions does current flow?

A

A noninvasive stimulation of the brain caused by passing a
weak electrical alternating current through it, with the frequency of the alternation interacting with the brain’s own rhythmical activity

Alternating directions

36
Q

What is the function of tDCS?

A

Can stimulate neural rhythms

37
Q

What happens to the stimulating pads in tACS and tRNS? Why?

A

They change status between anodal and cathodal continually since the direction of the current shifts back and forth

38
Q

What is the impact of the noise involved in tRNS?

A

Seems to increase cognitive performance, similarly to anodal tDCS

BBB (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions