Table 1.
Parameter ϑi = πiexp(Θi) | Interpretation | Prior |
|
---|---|---|---|
Mean: πi | Variance: Θi = N(0,σi) | ||
Observation model | |||
αu | Exogenous white input | παu = 0 | σαu = 1/16 |
αs | Channel specific white noise | παs = 0 | σαs = 1/16 |
αc | White noise common to all channels | παc = 0 | σαc = 1/16 |
βu | Exogenous pink input | πβs = 0 | σβu = 1/16 |
βs | Channel specific pink noise | πβc = 0 | σβs = 1/16 |
βc | Pink noise common to all channels | πθi = 1 | σθi = exp(8) |
θ1…s | Lead-field gain | πλ = 0 | σλ = 1 |
λ | Noise hyperparameter | ||
Neuronal sources | |||
κe/i | Excitatory/inhibitory rate constants | πκe = 4 ms− 1πκi = 16 ms− 1 | σκe = 1/8 σκi = 1/8 |
He/i | Excitatory/inhibitory maximum post-synaptic potentials | πHe = 8 mV πHi = 32 mV | σHe = 1/16 σHi = 1/16 |
γ1,2,3,4,5 | Intrinsic connections | πγ1 = 128 | σγ1 = 0 |
πγ2 = 128 | σγ2 = 0 | ||
πγ3 = 64 | σγ3 = 0 | ||
πγ4 = 64 | σγ4 = 0 | ||
πγ5 = 4 | σγ5 = 0 | ||
AF | Forward extrinsic connections | πAF = 32 | σAF = 1/2 |
AB | Backward extrinsic connections | πAB = 16 | σAB = 1/2 |
AL | Lateral extrinsic connections | πAL = 4 | σAL = 1/2 |
C | Exogenous input | πC = 1 | σc = 1/32 |
di | Intrinsic delays | πdi = 2 | σdi = 1/16 |
de | Extrinsic delays | πde = 10 | σde = 1/32 |
Design βki | Trial specific changes | πβki = 1 | σβki = 1/2 |
In practice, the non-negative parameters of this model are given log-normal priors, by assuming a Gaussian density on a scale parameter, Θi = N (0,σi), where ϑi = πiexp(Θi), and πi is the prior expectation and σi2 is its log-normal dispersion.