Fig. 1
From: Contrast and luminance adaptation alter neuronal coding and perception of stimulus orientation
Stimulus design and linear-response characteristics of V1 neurons. a Switching stimulus paradigm showing two example conditions: a contrast increment and mean luminance increment. Every 16.7 ms (two frames at 120 Hz), a grating with randomly selected orientation, phase, and spatial frequency was presented. b The gratings’ mean luminance or contrast was randomly selected from four conditions and was switched every 5 s, with a total presentation time of 60 min (maximum 720 switches). Here, we only analyse eight switches (indicated by coloured arrows), in which a single parameter changed. The colour code and line styles are consistent throughout the study. c The linear kernel quantifying the dynamics of orientation selectivity for a single neuron during the early (left, first 1.6 s) and late (right, last 1.6 s) phases of adaptation to high-contrast, low-luminance stimuli (i.e., the switch shown with solid dark blue arrow). Inset, temporal features were extracted from every linear kernel during adaptation. Population data of selective neurons comparing the differences in maximum modulation (d), peak time (e), and temporal width (f) between early and late phases for one adaptation condition (see the colour code). Small triangles indicate average; asterisks indicate significance (p < 0.01, t test). n = 390
