Fig. 3: Chronic calcium imaging of multiple visual areas throughout category learning.

a, Timeline of imaging time points (above) and stages of the behavioral paradigm (below). Each imaging time point consisted of 3–5 daily imaging sessions, in which a different area was imaged. 2P, two-photon imaging. b, Hue–lightness–saturation (HLS) maps showing visual cortex areas imaged using low-magnification two-photon microscopy (mouse M19). Hue represents the position of the preferred stimulus; pink denotes the center and trained stimulus location, and blue denotes eccentric stimulus locations (inset). Lightness represents response amplitude, and saturation represents selectivity. The overlaid area map is based on ref. ³⁷. See Extended Data Fig. 3 for three more examples. Scale bar, 250 µm. c, Example FOV regions (area PM, mouse M16), acquired 110 d apart. Green, GCaMP6m; red, mRuby2. Scale bar, 20 µm. d, Top left, example stimuli for categorization (see also g). Top right and bottom, left/right choice fraction of three example mice. Dashed lines denote trained category boundaries, and solid lines denote individually learned category boundaries. Data from all ten mice are depicted in Extended Data Fig. 4b. e, Fraction of ‘lick-left’ choices (mean ± s.e.m. across mice; n = 10), as a function of the stimulus’ distance to the category boundary. Blue represents baseline time points 3 and 4. Black represents time point ‘learned 1’. Gray represents individual mice at time point ‘learned 1’. f, Performance (mean ± s.e.m.) after visual cortex was treated with artificial cerebrospinal fluid (aCSF; black, control) or muscimol (red, inactivation; one-sided WMPSR test, W = 15, P = 0.031; n = 5 mice). g, Example of full stimulus space. Dark red/blue, initial stimulus discrimination. Pink/light blue, reduced category space. h, HLS maps of five time points (area LM, mouse M16). Hue represents the preferred category (pink denotes right, blue denotes left), lightness the response amplitude, and saturation the selectivity (legend). Scale bar, 20 µm. i, Stimulus-aligned inferred spike activity across five imaging sessions for two example neurons. The x axes show time (−0.4 to +3.0 s around stimulus onset), and the y axes show response amplitude (vertical scale bars show one inferred spike per second, and horizontal scale bars show 2 s). Plots are organized into grids matching the stimulus and color space in g. *P < 0.05.