EEG Flashcards
What does EEG actually stand for?
Electroencephalography
Electro…encephalo…graphy
What is Hans Berger (1873-1941) known for?
Detected the first EEG signal in 1924, with electrodes attached to the scalp of his wife
The spatial resolution of EEG is excellent, T/F
FALSE
The temporal resolution is great, but the spatial resolution is not so good
How many channels does EEG have?
256
Does EEG activity reflect…
A) action potentials
B) post-synaptic potentials
B) post-synaptic potentials
…voltages that arise when neurotransmitters bind to receptors on the membrane of the post-synaptic cell
What is the size of a ‘functional unit’ of simultaneously activated neurons, for the purposes of EEG?
(Unit is in neurons)
> 10,000
With EEG, you easily can detect signals from sulci but not so much from gyri, T/F
FALSE
The gyri is the main game
Are gyri the top bit or the folder bit?
Top bit
In EEG, what is the ‘inverse problem’?
‘Mathematically, if the sources are known, the resulting scalp configuration of signals can be reconstructed; however, the reverse is not true – one given scalp configuration of signals can have multiple dipole solutions!’
In EEG, where might one place a ‘reference electrode’?
A neutral point such as the tip of the nose or the mastoids
What is the typical amplitude of an EEG signal?
10μV to 100μV
By what factor would you normally amplify EEG signals?
hint: it’s a range, and a large one
1,000 to 100,000
In the context of EEG, what is ‘artefact rejection’?
The process of finding the traces of things that are not brain signals, and clearing them out of the EEG signal.
What are examples of ‘artefacts’ than would need rejecting when cleaning up EEG data?
- sweating
- electrical noise (‘notch filter)
- eye blinks etc1
Event related potentials (ERP) are the brain signals that are associated with a given event (such as a cognitive process)
Yes they are
