(a) Task schematic showing the time course of a single trial. In each trial, one of a combination of eight different directions and five contrasts, or a 0% contrast probe trial (isoluminant gray blank screen) was presented (ratio 1:5 of 0%-contrast-probe:stimulus trials). When mice made a licking response during stimulus presentation, the visual stimulus was turned off and sugar water was presented. (b) Schematic of experimental setup. During task performance, we recorded eye movements with an infrared-sensitive camera, licking responses, and running on a treadmill. (c) All eight animals performed statistically significant stimulus detection during neural recordings, as quantified by non-overlapping 2.5th–97.5th Clopper–Pearson (CP) percentile confidence intervals (95% CI) (p<0.05) of behavioral response proportions for 0% and 100% contrast probe trials. (d) Example of simultaneously recorded behavioral measures, population heterogeneity, mean population dF/F0, and traces of neurons labeled in panel (b) Vertical colored bars represent stimulus presentations; width, color, and saturation represent duration, orientation, and contrast, respectively. (e, f) Animals showed significant increases in behavioral response (behav. resp.) proportion (linear regression analysis, see ‘Materials and methods’, p<0.001) (e) and reductions in reaction time (p<0.01); (f) with higher stimulus contrasts. Shaded areas show the standard error of the mean. Statistical significance: **p<0.01; ***p<0.001.
DOI:
http://dx.doi.org/10.7554/eLife.10163.003