Brain stimulation Flashcards
What is meant by brain stimulation?
Noninvasive technique using a magnet coil to induce voltage. Device held over scalp and pulsed at a varying rate.
What are the types of brain stimulation?
TMS- transcranial magnetic stimulation
tDCS- Transcranial direct current stimulation.
What type of evidence does brain scans and stimulation provide?
Correlational.
What does stimulation do to the neurons and what can it be used to investigate?
It adds neuronal noise to a neuronal system, temporarily disrupting or enhancing its function, stimulating inhibitory intracortical networks. It is used to investigate casual function of a cortical target area.
What do the creation of virtual lesions do?
Happens in TMS, they can temporarily impair or disconnect brain areas that allow us to study their casual involvement in certain brain functions.
How does a control condition for TMS research happen?
Usually the same person at a different time given a ‘sham’ condition in which the brain pulse is fake or a region not involved in the experiment is stimulated instead.
What can be observed if the brain region is involved during a TMS?
Difference in performance (errors) and speed (reaction times) compared to the control.
What type of research can use TMS?
Brain research such as precise localisation of brain regions, can be used in combination with EEG and fMRI.
Medical research such as therapeutic benefits of TMS for many medical conditions such as depression, addiction, strokes, chronic pain and Parkinson’s.
How does TMS work?
Using a magnetic coil to induce voltage to the brain tissue, device held over scalp in target area and pulsed at different frequencies.
How does the function of tDCS differ from TMS?
Less expensive alternative, uses constant low frequency electrical stimulation to activate astrocytes and increase neuronal excitability and connectivity.
What are the two types of stimulation with tDCS?
Anodal stimulation which acts to excite neuronal activity.
Cathodal stimulation inhibits or reduces neuronal activity.
What are the advantages of tDCS?
Cheap, non invasive
Easy and portable
Minimal side effects (only slight itching or tingles)
Seen as a valuable therapeutic tool.
Research supports cognitive improvements.
What are the cons of tDCS?
Too easy to use therefore can be abused
Long term consequences on cognition not clear.
