Skip to main content
. 2009 May 1;5(5):e1000373. doi: 10.1371/journal.pcbi.1000373

Figure 5. Effects of feedback on LGN on-center and off-center type cells.

Figure 5

Dashed: probability that the LGN cell coding for this location is active (i.e. response>0) in the first feedforward sweep of the model when a V1 region will subsequently be selected that codes for the same or opposite polarity, blank: probability that the LGN cell is active after the first feedforward-feedback pass (i.e. when feedback exerts its effect) when a V1 region is selected that codes for the same or opposite polarity. Red: on-center type cell, blue: off-center type cell. The results were obtained after presenting the model with a white-noise stimulus every 100 milliseconds for a total of 10,000 images. Comparing initial feedforward activity with subsequent LGN activity shows that feedback has a negative influence on cells of similar sign, and a positive influence on cells of opposite sign. Thus, the probability that an LGN off-cell is active increases after feedback from a V1 on-region (lower right, blue), and the probability that an LGN on-type cell is active decreases after feedback from an on-region in V1 (upper left, red).