Extended Data Fig. 4: Receptive Fields and Spatial Information of Units in Hindpaw S1 and Forepaw S1.
From: Cortical responses to touch reflect subcortical integration of LTMR signals
a, Left: stimulus locations used to probe receptive fields with 10-mN step indentations for hindpaw S1. The grid size is 5 × 5 mm. Right: Mean (± s.e.m.) spatial information for all hindpaw S1 units during the course of the 10-mN step indentation. b, Distribution of spatial information across all hindpaw S1 units at the onset (ON; 20-70 ms after step onset), sustained (SUS; 250-500 ms after step onset), and offset (OFF; 20-70 ms after step offset) portions of the 10-mN step indentation. c, A correlation (Pearson r = 0.79, p = 1.4 × 10−179) was apparent between the amount of spatial information at the onset and offset of the step indentation, but the amount of spatial information at the onset was reliably greater than that at the offset. Colors represent units from different recordings. Gray dashed line is the unity line. d, RF sizes of FS hindpaw S1 units (n = 201 units) were larger than those of RS hindpaw S1 units (n = 649 units). Two-sided Mann-Whitney U = 56,703, p = 1.6 × 10−10. Box plot element definitions: center line, median; box limits, upper and lower quartiles; whiskers, 1.5× interquartile range; points, outliers. e, Example RFs for units with varying degrees of spatial information at the onset. The mean spatial information over the 20-70 ms after the onset of the step indentation is displayed above the heatmap for each unit. The magnitude of the response (rather than the size of the RF) appeared to account for most of the differences in spatial information. f, Top: Mean (± s.e.m.) spatial information for all units in a recording from an Scnn1a-tg3-Cre;R26LSL-ChR2 mouse. The spatial information for two optotagged layer IV units (cyan and magenta) are overlaid. Bottom: Example RFs for these two optotagged units are qualitatively similar to those displayed in e. g, As in a, for forepaw S1. Stimuli were applied to 16 locations in a 4 × 4 mm grid. Thus, the spatial information calculated from forepaw S1 recordings is not directly comparable to that calculated from hindpaw S1 recordings. h, As in b, for forepaw S1. i, As in c, for forepaw S1. (Pearson r = 0.71, p = 1.2 × 10−99). j, As in d, for forepaw S1 (n = 435 RS and FS units, respectively; Two-sided Mann-Whitney U = 31,348). k, As in e, for forepaw S1. l, Receptive field sizes for hindpaw (n = 850 units from 12 recordings in 8 mice) and forepaw S1 (n = 677 units from 9 recordings in 4 mice) units. Two-sided Mann-Whitney U = 266932. Box plot element definitions as in d.
