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Inhibitory
$a_{ii}$
$a_{ie}$
$\tau_i$
$\theta_i$
$g_i$
$\sigma_{ix}$
$\sigma_{iy}$
$N_i$
$\gamma_{ii}$
$\gamma_{ie}$
Excitatory
$a_{ee}$
$a_{ei}$
$\tau_e$
$\theta_e$
$g_e$
$\sigma_{ex}$
$\sigma_{ey}$
$N_e$
$\gamma_{ee}$
$\gamma_{ei}$

Time stepping
$\Delta t$
Skip
Stimulus
$A$
Presets
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E-cell firing rate ∈[0,1]
I-cell firing rate ∈[0,1]
E/I trajectories in phase space
Peripheral region
E-cell firing rate
I-cell firing rate
E/I trajectories in phase space
Stimulated region
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Wave State Demonstration

This demonstration is designed to illustrate a hypotehtical wave mode seen during optogentic stimulation in motor cortex. In this mode, the stimulated region forces damped traveling waves in the periphery at a ratio of 2:1. Additionally, there is instability inside the stimulated region, leading to traveling waves across the stimulation area that originate at the boundary. The Stimulated region has a radius of 30 pixels, the stimulus mask has been smoothed with a Gaussian kernel with a standard deviation of 4 piexls, given the stimulated region a soft boundary. Heterogeneity is added to the time constants (in a somewhat hacked way that I can explain or try to clean up), and is also smoothed with a Gaussian kernel of 4 pixels. These new additions are not reflected in the equations.
Simulation
\[\textrm{E-cells: } \tau_e \dot{U_e} = -U_e + f( (1+\gamma_{ee} S(t)) a_{ee} \cdot K_e \star U_e - (1+\gamma_{ie} S(t)) a_{ie} \cdot K_i \star U_i - \theta_e + g_e S(t) )\] \[\textrm{I-cells: } \tau_i \dot{U_i} = -U_i + f( (1+\gamma_{ei} S(t)) a_{ei} \cdot K_e \star U_e - (1+\gamma_{ii} S(t)) a_{ii} \cdot K_i \star U_i - \theta_i + g_i S(t) )\] \[\textrm{Interaction kernel (normalized to 1): } K_{e,i}(x,y) \propto \exp(\frac{1}{2} \frac{x^2}{\sigma_{x\,e,i}^2}+\frac{1}{2} \frac{y^2}{\sigma_{y\,e,i}^2})\]