Dynamic Encoding of Natural Luminance Sequences by LGN Bursts
Figure 2
The Luminance Sequences That Trigger Burst Events
(A) The BTAs calculated from simulated responses to a two-minute segment of natural scene movie at different resting potentials. The resting potential of the model and BP of the response corresponding to each BTA are indicated. Full spatiotemporal BTAs were calculated, and the plots show the intensity of the BTA averaged over all pixels in the RF center. Each BTA was scaled so that the integral of its absolute value was 1.
(B) A plot of E/I ratio of the BTA versus resting potential for simulated responses to natural scene movies. E/I ratio was calculated as the ratio of the areas of the excitatory and inhibitory components of the BTA (see inset).
(C) The BTAs calculated from the experimental responses of three LGN Y cells recorded at different times during a single experiment to natural scene movies (average of nine different two-minute segments). The BP of each response is indicated. Spatiotemporal BTAs were averaged and scaled as in (A).
(D) A scatter plot of E/I ratio of the BTA versus BP for a sample of 27 LGN cells (11 X cells, 16 Y cells). E/I ratio was calculated as described in (B).
(E) The normalized BTAs for three LGN Y cells. BTAs were normalized for the temporal correlations in the natural scene movies by spectral normalization (see Materials and Methods). The non-normalized BTAs corresponding to each normalized BTAs are shown in gray (same BTAs as in (C)).
(F) A scatter plot of E/I ratio of the normalized BTA versus BP for a sample of 27 LGN cells. E/I ratio was calculated as described in (B).