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Additional file 3: Supplementary Figure 3. Acute optogenetic stimulation does not induce hyperalgesia or the release of inflammatory mediators in wild type mice or primary sensory neurons. Wild type (C57BL/6) mice were anesthetized and subjected to optogenetic stimulation using 470 nm LED (blue) or 595 nm LED (yellow light) for 15 min on the dorsum of the right hind paw. (A) Mechanical hypersensitivity was assessed 5 h later, using von Frey filaments. Blue or yellow light stimulation did not induce any mechanical hypersensitivity to wild type animals. Data is represented as individual mouse data points with mean ± SEM. One-way ANOVA followed by Tukey’s multiple comparisons test between groups. N = 5 per group. ns: not significant. (B-D) Levels of HMGB1, CGRP and substance P were measured in the interstitial fluids of the paws at 5 h post-stimulation. Data is represented as individual mouse data points with mean ± SEM. One-way ANOVA followed by Tukey’s multiple comparisons test between groups. N = 5-10 per group. ns: not significant.

Additional file 1: Supplementary Figure 1. Light activated sensory neurons release inflammatory mediators. DRG sensory neurons harvested from Vglut2-Cre/ChR2-eYFP mice were cultured for 48–72 h and then stimulated with blue light (470 nm) at 20 Hz, 10% duty cycle for 15 min. Supernatant was harvested at indicated time points, and levels of HMGB1 (A), substance P (B) and CGRP (C) were quantified. N = 4-5 per group. *P < 0.05, **P < 0.01, ***P < 0.001.

Additional file 2: Supplementary Figure 2. Experimental setup for optogenetic and HFES. (A) Animals were induced and maintained under anesthesia using isoflurane (1.5-2%). The right hind paw was extended and secured to minimize movement during stimulation. (B) The LED (470 or 595 nm) was positioned 1 cm above the right hind paw. (C) Optogenetic stimulation was applied to the right hind paw for 15 min (3 Hz, 20% Duty Cycle). (D) Immediately after optogenetic stimulation, two probe tips covered with a conductive gel (Spectra 360 gel) were positioned above the sciatic nerve. Transcutaneous HFES (20.6 kHz) was applied for 5 min parallel and perpendicular to the sciatic nerve for a total of 10 min. After electrical stimulation, the animal was allowed to recover in a clean cage.

This data archive contains all code and data necessary to replicate each main text and supplementary figure and associated statistical comparisons in the following article:Williams, B., Del Rosario, J., Muzzu, T., Peelman, K., Coletta, S., bichler, E. K., Speed, A., Meyer-Baese, L., Saleem, A. B. & Haider, B. (2021). Spatial modulation of dark versus bright stimulus responses in the mouse visual system. Current Biology, 31, 1-8.The data and code is compatible with Matlab 2018 or later.The data archive is organized as self-contained subfolders corresponding to the results found in each main figure (e.g., folder 'F1' for results of Figure 1). Each subfolder contains code that loads the minimally processed data structures for replication of the published figures.Abstract of associated publication:A fundamental task of the visual system is to respond to both increases and decreases of luminance with action potentials (ON and OFF responses). OFF responses are stronger, faster, and more salient than ON responses in primary visual cortex (V1) of both cats and primates, but in ferrets and mice ON responses can be stronger, weaker, or balanced in comparison to OFF responses. These discrepancies could arise from differences in species, experimental techniques, or stimulus properties, particularly retinotopic location in the visual field, as has been speculated; however, the role of retinotopy for ON/OFF dominance has not been systematically tested across multiple scales of neural activity within species. Here, we measured OFF versus ON responses across large portions of visual space with silicon probe and whole-cell patch-clamp recordings in mouse V1 and lateral geniculate nucleus (LGN). We found that OFF responses dominated in the central visual field, whereas ON and OFF responses were more balanced in the periphery. These findings were consistent across local field potential (LFP), spikes, and subthreshold membrane potential in V1, and were aligned with spatial biases in ON and OFF responses in LGN. Our findings reveal that retinotopy may provide a common organizing principle for spatial modulation of OFF versus ON processing in mammalian visual systems.Code repository can be found at https://doi.org/10.6084/m9.figshare.14872143Post created on '02-Jul-2021 17:46:34'