The Generation and Modulation of Distinct Gamma Oscillations with Local, Horizontal, and Feedback Connections in the Primary Visual Cortex: A Model Study on Large-Scale Networks

Figure 1

The network architecture of a large scale network model. Small grey circular patches in (a) represent 15 by 15 local components in the network. These local components are placed horizontally on a plane parallel to cortical surface which mimic hypercolumns in V1. The spatial range of activation zone, or the number of activated E-I units in the model, is dependent on the size of external visual stimulus. Each local component in (b) consists of excitatory (E) and inhibitory (I) component connected with local connection , , , and . In the cortical space, the E and I components receive feedforward input (, ) from subcortical regions (LGN) that are driven by visual stimuli, horizontal inputs ( and ) from other E-I units and receives feedback (, ) from higher visual cortex (G). The higher visual cortex (G) receives feedforward () input from V1 as well.