Typical example of shift in orientation preference and response modulations.

<p>A: The first 12 min adaptation displaces the preferred orientation of the cell by 15.5° toward the adapting stimulus. The head arrow indicates the non-preferred adapting stimulus. Following a recovery period of 60 min, the cell recovered its control preferred orientation at 9.0°. Adaptation II produces an identical attractive shift of 15.1°. B, C and D: Histograms shows the response modulations at the control preferred orientation, the new preferred orientation after adaptations and the baseline level (θ = 90°), respectively. At the control preferred orientation, the mean firing rate of cell decrease after adaptation I (<i>t</i>-test, p<0.001) and returned to control level in 60 min. In parallel, the mean firing rate increase by 27% at the new preferred orientation (<i>t</i>-test, p<0.0001). Following recovery, the firing rate further increases: 48% in comparison to adaptation I (<i>t</i>-test, p<0.0001). Baseline level remains unchanged across conditions. E and F: Peri-stimulus time histograms (PSTH) are illustrated for the neuron responding to orientations in C and D, respectively. Blue curves; control condition, red curves; adaptation I, black curves; adaptation II.