EEG (electroencephalography) Questions And Answers

EEG pros correct answer: Excellent time resolution - Cognitive, perceptual, linguistic, emotional processes are fast and dynamic - For example, consider theta band (4-8 Hz), a slow rhythm but quite fast for our conscious experience - Or consider gamma (30 -80 Hz) Direct indicator of neuronal activity Multidimensional (time, space, frequency, power, phase, connectivity etc) Portability (observing brain in action) Relatively inexpensive EEG cons correct answer: It is not well-suited for precise functional localisation It is not well-suited for measuring deep brain structures (e.g., putamen, thalamus, nucleus accumbens)--> Sub-optimal method: where in the brain does process X occur or is information Y stored It is also not very well-suited to study very slowly fluctuating process with uncertain and variable time course EEG reflects the ___________ of electrical potential overtime, created by the current flows originating from neuronal populations correct answer: differences Two types of neuronal electrical activity: correct answer: (i) action potential (AP) (ii) postsynaptic potential (PSP) Propagation of the Action Potential correct answer: [see image] Chemical synapses correct answer: cause local changes in postsynaptic membrane potentials, through neurotransmitters. Information transmits with some delay on the order of a millisecond. electrical synapses (gap junctions) correct answer: Ions flow directly through large channels into adjacent cells, with no time delay Post-Synaptic Potential (PSP) correct answer: An electrical potential initiated at a postsynpatic site that can vary in amplitude and spreads passively across the cell membrane, decreasing in strength with time and distance