Fig. 3: Cell-type-specific activation of the 5-HT2A receptor pathway and modulations of evoked activity.
a, b Visual responses (dots indicate visual stimulus timing) in control conditions (V, black) and with additional 5-HT2A receptor activation (Vph, blue; horizontal bars). Gray traces represent (Vph-V). a Photostimulation of the 5-HT2A pathway in pyramidal neurons. Normalized evoked activity of excitatory and inhibitory neurons (dark orange and blue box, respectively), mean ± SEM (shadings) of n = 55 excitatory units and n = 44 inhibitory units 11 in NEX-Cre mice. b Photostimulation of the 5-HT2A pathway in PV interneurons. Normalized evoked activity of inhibitory and excitatory neurons (dark blue and light orange box, respectively), mean ± SEM (shadings) of n = 73 inhibitory units and n = 56 excitatory units recorded in 14 PV-Cre mice. c Violin plot of opto-index (OI) based on response magnitude (difference between peak amplitude and baseline, see scheme at left) for excitatory (dark orange circles) and inhibitory (light blue circles) neurons in (a). Compared are values for the control visual stimulus #1 (pre-photostimulation) and stimulus #4 (during photostimulation; x-axis in (e) shows stimulus numbering). d Violin plot of the same analysis as in (c) for data shown in (b). ***p = 0.0007, two-sample Kolmogorov–Smirnov test. e Quantification of response magnitude of the conditions shown in (a, b). Color scheme denotes cell type and is matched to box colors above. ***p < 0.00017, **p < 0.0017, two-sided paired sample t-test with Bonferroni correction; exact p-values of comparisons are reported in the Source Data file. f Comparison between response magnitude evoked by stimulus #1 and the average of magnitude values obtained for stimuli #2–4 for each excitatory unit during optogenetic activation of 5-HT2A in PV interneurons (see b, right). Control (V, black circles), photostimulation conditions (Vph, blue circles), data normalized to the unit with the highest firing rate (n = 58). Lines represent linear regression for V and Vph, identity line (dashed red). Inset represents regression coefficients (mean ± SEM, n = 116). The negative value of the coefficient β4 indicates divisive reduction of the magnitude in the Vph condition. ***p = 6.09 × 10−37 (β2), *p = 0.044 (β4), two-sided one-sample t-test. Source data are provided as a Source Data file.
