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 3

Phase diagram for the number of gamma oscillations and the modulation of existing gamma in HC network without FB. (a) shows the power spectrums of the LFPs from two example networks. Although both of the two networks have local RC and HC, but their HC connection strengths are different. There are two distinct oscillatory states (b): (1) one gamma oscillation and (2) two gamma oscillations. These oscillatory states are dependent on parameters ( and ) for HC connection strengths of the network in (b). The power of slow and fast gamma for different connection strength is shown in (c) and (d), respectively. (e) shows how the peak power changes with connection weight corresponding to color plots (c) and (d). The black lines denote the cases of slow gamma (dashed black line for , and solid black line for ), and grey lines are for fast gamma (dashed grey line is for , and solid grey line is for ). The peak frequency of slow and fast gamma for different connection strength is shown in (f) and (g), respectively. (h) shows how peak frequency changes of connection weight corresponding to the color plot in (c) and (d). The black line denotes the case of slow gamma (dashed line for , and solid line for ) and grey line is for that of fast gamma (dashed line for , and solid line for ).