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Consider two neurons, A and B, which reciprocally inhibit each other. If both of the neurons receive input at the same time, it seems to me that no oscillation will occur between the two. Such would occur only if one of the two is initially "favored" over the other. So what I'm wondering is, how does that happen? Is it essentially random?

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Honi's got most of it, but it also involves refractory periods and post-inhibitory characteristics of the membrane ("rebound"). – Chuck Sherrington Apr 30 '13 at 23:07
up vote 3 down vote accepted

Noise will ensure that there will not be perfect symmetry and therefore that one has an advantage to fire first. Whichever one fires first will inhibit the other and ensure that the first one to fire will stay on for however long the dynamics of the pattern generator allow.

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I had a feeling that that's the case. So randomly (e.g. Gaussian) distributed noise is the sole or main deciding factor here? – visual-kinetic Apr 30 '13 at 21:13
noise comes in so many forms. you can have noise in the synapses, you can have noise in somatic conductances, the cells can be different sizes, the cells can have different time constants, etc. – honi May 2 '13 at 1:55
I down-voted this answer. Noise does inject assymetry into the system. However, a much stronger, system-regulated mechanism of assymetey is connection strength. This can come in the form of 1) number of interconnections, 2) regulation of the amount of neurotransmitter released 3) autoregulation of a specific cell 4) regulation of neurotransmitter receptor density 5) other connections or astrocytes or even local environment regulating the excitability of individual cells. – Keegan Keplinger May 3 '13 at 11:15
as i described in my explanatory note just above your comment. – honi May 3 '13 at 13:09
I would call it signal, not noise. But I think you could anyway improve your answer a lot... – Keegan Keplinger May 4 '13 at 3:30

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