JHA410H1 Lecture Notes - Lecture 9: Default Mode Network, Medulloblastoma, Oligodendrocyte
Document Summary
It is clear that a large # of neurons must be firing in synchronized discharges for us to measure thier activity outside of the brain. These synchronized discharges can occur: as a single event evoked response or in an ongoing repetitive way endogenous oscillations. The first piece of information we can get from brain ossicilations in amplitude. This makes sense because mechanically, when there is cross-talk between brain regions you can only do it so fast. These delta/theta oscillations would occur during sleep or meditation and would be differently widespread throughout the brain: at mid-level frequencies (i. e. 4-12hz) large population of neurons local/regional activity. These frequencies might be alpha or beta and correspond to smaller number of neurons being recruited - activity within a whole brain region (e. g. v1) Alpha/beta ossicilations would occur during sensory processing and would repersent activity in the corresponding sensory brain region: at the highest frequencies (i. e. 30hz+) very localized group neurons very localized activity.
