Figure 6.

Modeling the impacts of different tuning patterns of synaptic input strengths on spike latency tuning. A, Average tuning curves of peak excitatory responses before (red) and after (black) cortical silencing, and of peak intracortical excitatory responses (blue) derived by subtracting the thalamic response from the total excitatory response. Individual tuning curves were normalized before averaging. Whiskers indicate SE. n = 10. B, Average tuning curves of peak excitatory (black) and inhibitory (red) responses. Whiskers indicate SE. n = 14. C, Temporal profiles of synaptic inputs applied in the simulation: thalamocortical input (blue), total excitatory input (red), inhibitory input (black). Calibration: 1 nS, 10 ms. D, Change of integration time with the increase of strength of intracortical excitatory or inhibitory input. The thalamic input was fixed at 2.86 nS, while intracortical excitatory and inhibitory inputs were included separately. Inhibitory input above 5.21 nS eliminated spikes. E, Top, Tuning curves of integration time resulting from thalamic input only (black), from thalamic input plus cotuned excitatory intracortical input (blue), and from thalamic input plus sharply tuned excitatory intracortical input (red). The synaptic strengths at the BF are as follows: thalamic input, 2.86 nS; intracortical excitatory input, 2.86 nS. Bottom, Tuning curves of relative spike latency. F, Top, Tuning curves of integration time resulting from excitatory input only (black), from excitatory input plus cotuned inhibitory input (red), and from excitatory input plus broadly tuned inhibitory input (blue). The synaptic strengths at the BF are as follows: excitatory input, 5.72 nS; inhibitory input, 6.86 nS. Bottom, Tuning curves of relative spike latency. The dashed curve depicts the latency tuning of thalamic input. *p < 0.01; **p < 0.001 (paired t test).