Fig. 1: Mice learn discriminating information-integration categories in a touch screen operant chamber.
From: Mouse visual cortex areas represent perceptual and semantic features of learned visual categories
a, Behavioral chamber, from above. Touch screens (v) display visual stimuli and record screen presses; food pellet rewards (r) are delivered via a pellet feeder into a dish. A drinking bottle, house light, speaker, and lever are positioned on the east and south walls. b, Mean (±s.e.m.) learning curve. Gray lines represent individual animals (n = 8 mice). Latin numerals denote category training stages. Insets show active stimuli (black) and not-yet-introduced stimuli (gray). c, Fraction of stimuli chosen as a function of the stimulus’ distance to the category boundary (black lines denote the mean ± s.e.m., and gray lines represent individual mice; two-sided Kruskal–Wallis test, H(11) = 90.8, P = 1.17 × 10−14, post hoc two-sided Wilcoxon matched-pairs signed-rank (WMPSR) test; n = 8 mice). d, Fraction of correct trials for novel and familiar stimuli. ‘First’ represents the mean (±s.e.m.) performance on the first trial of newly introduced stimuli at stages V and VI (only for first training session of each stage). ‘Last’ represents the performance for the same stimuli but in the first trials of the last training sessions of stages V and VI. Gray lines represent individual mice (two mice had identical performances at 0.8; two-sided WMPSR test: W = 5, P = 0.50; n = 8 mice). e, The fraction of trials on which a stimulus was chosen (data from stage VI) for each mouse (M01–M08). White tiles diagonally intersecting plots stand for stimuli directly on the category boundary, which were not shown. The black line represents the fitted, behaviorally expressed category boundary. NS (not significant), P > 0.05; *P < 0.05.
