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A radial map of multi-whisker correlation selectivity in the rat barrel cortex

View Article: PubMed Central - PubMed

ABSTRACT

In the barrel cortex, several features of single-whisker stimuli are organized in functional maps. The barrel cortex also encodes spatio-temporal correlation patterns of multi-whisker inputs, but so far the cortical mapping of neurons tuned to such input statistics is unknown. Here we report that layer 2/3 of the rat barrel cortex contains an additional functional map based on neuronal tuning to correlated versus uncorrelated multi-whisker stimuli: neuron responses to uncorrelated multi-whisker stimulation are strongest above barrel centres, whereas neuron responses to correlated and anti-correlated multi-whisker stimulation peak above the barrel–septal borders, forming rings of multi-whisker synchrony-preferring cells.

No MeSH data available.


A radial map of responses evoked by correlated (purple) versus uncorrelated stimulations (measured on the PW, green).(a) Z-score-derived correlated/uncorrelated stimulation preference index in an individual experiment. Marginal curves: example stimulus-triggered average calcium transients. Grey background: layer 4 barrel. White: septum. (b) Projection of Z-scores from a in normalized barrel radius coordinates. Lines: local Z-score median. (c) Projection in a normalized barrel of all recorded neurons. Colour code: Z-score-derived correlated/uncorrelated stimulation preference index. (d) Radial profile (364 neurons per bin) of mean correlated/uncorrelated stimulation-evoked dF/F, for all recorded neurons. Light background: bootstrap-derived 70% confidence interval. ***Mann–Whitney P=5.3E-4 for uncorrelated and 2.1E-6 for correlated stimulation-evoked responses. **P=2.0E-3. (e) Same as d for Z-scores. **Mann–Whitney P=2.1E-3 for uncorrelated and 3.6E-3 for correlated stimulation-evoked responses. ***Mann–Whitney P=5.0E-7. (f) Normalized radial profile (364 neurons per bin) of the proportion of neurons preferring correlated (purple) or uncorrelated (green) stimulations, among all responsive neurons. ***Fisher exact P=3.5E-9 for correlated and 1.9E-4 for uncorrelated stimulation-preferring neurons. **P=3.3E-2. (g) Same as f for significant tuning to correlated versus uncorrelated stimulations. ***Fisher exact P=6.1E-5. **P=8.2E-3 (364 neurons per bin). (h) Correlated stimulation-evoked mean Z-scores for all neurons, in normalized septal coordinate (444 neurons per bin). From left to right, equal neuron count bins contain neurons from area above barrel edge, septum edge and septum centre. **Mann–Whitney P=2.8E-3. (i) Same as h for the proportion of responsive correlation-preferring neurons over all cells. **Fisher exact P=2.2E-3 (444 neurons per bin).
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f2: A radial map of responses evoked by correlated (purple) versus uncorrelated stimulations (measured on the PW, green).(a) Z-score-derived correlated/uncorrelated stimulation preference index in an individual experiment. Marginal curves: example stimulus-triggered average calcium transients. Grey background: layer 4 barrel. White: septum. (b) Projection of Z-scores from a in normalized barrel radius coordinates. Lines: local Z-score median. (c) Projection in a normalized barrel of all recorded neurons. Colour code: Z-score-derived correlated/uncorrelated stimulation preference index. (d) Radial profile (364 neurons per bin) of mean correlated/uncorrelated stimulation-evoked dF/F, for all recorded neurons. Light background: bootstrap-derived 70% confidence interval. ***Mann–Whitney P=5.3E-4 for uncorrelated and 2.1E-6 for correlated stimulation-evoked responses. **P=2.0E-3. (e) Same as d for Z-scores. **Mann–Whitney P=2.1E-3 for uncorrelated and 3.6E-3 for correlated stimulation-evoked responses. ***Mann–Whitney P=5.0E-7. (f) Normalized radial profile (364 neurons per bin) of the proportion of neurons preferring correlated (purple) or uncorrelated (green) stimulations, among all responsive neurons. ***Fisher exact P=3.5E-9 for correlated and 1.9E-4 for uncorrelated stimulation-preferring neurons. **P=3.3E-2. (g) Same as f for significant tuning to correlated versus uncorrelated stimulations. ***Fisher exact P=6.1E-5. **P=8.2E-3 (364 neurons per bin). (h) Correlated stimulation-evoked mean Z-scores for all neurons, in normalized septal coordinate (444 neurons per bin). From left to right, equal neuron count bins contain neurons from area above barrel edge, septum edge and septum centre. **Mann–Whitney P=2.8E-3. (i) Same as h for the proportion of responsive correlation-preferring neurons over all cells. **Fisher exact P=2.2E-3 (444 neurons per bin).

Mentions: We then explored the spatial organization of neurons tuned to multi-whisker deflection statistics on top of the barrel map. In individual experiments, whereas responses to the PW during uncorrelated stimuli peaked above the centre of the corresponding barrel, responses to correlated stimulations were maximal in neurons at the periphery of barrels (Fig. 2a, Supplementary Fig. 4b–d and Supplementary Fig. 6). We confirmed this observation (Fig. 2b) by projecting the radial position of all neurons in a normalized radial space (Supplementary Fig. 7a). When data from all experiments were combined (Fig. 2c), we observed the same radial organization of the responses, considering either the mean amplitudes of the fluorescent transient (Fig. 2d), the mean Z-scores (Fig. 2e), the proportion of neurons preferring one of the two stimuli (Fig. 2f) or the proportion of neurons significantly selective to one of the two stimuli (Fig. 2g). These radial profiles produce a concentric map of relative responses to the two types of multi-whisker correlation stimuli (Fig. 2c).


A radial map of multi-whisker correlation selectivity in the rat barrel cortex
A radial map of responses evoked by correlated (purple) versus uncorrelated stimulations (measured on the PW, green).(a) Z-score-derived correlated/uncorrelated stimulation preference index in an individual experiment. Marginal curves: example stimulus-triggered average calcium transients. Grey background: layer 4 barrel. White: septum. (b) Projection of Z-scores from a in normalized barrel radius coordinates. Lines: local Z-score median. (c) Projection in a normalized barrel of all recorded neurons. Colour code: Z-score-derived correlated/uncorrelated stimulation preference index. (d) Radial profile (364 neurons per bin) of mean correlated/uncorrelated stimulation-evoked dF/F, for all recorded neurons. Light background: bootstrap-derived 70% confidence interval. ***Mann–Whitney P=5.3E-4 for uncorrelated and 2.1E-6 for correlated stimulation-evoked responses. **P=2.0E-3. (e) Same as d for Z-scores. **Mann–Whitney P=2.1E-3 for uncorrelated and 3.6E-3 for correlated stimulation-evoked responses. ***Mann–Whitney P=5.0E-7. (f) Normalized radial profile (364 neurons per bin) of the proportion of neurons preferring correlated (purple) or uncorrelated (green) stimulations, among all responsive neurons. ***Fisher exact P=3.5E-9 for correlated and 1.9E-4 for uncorrelated stimulation-preferring neurons. **P=3.3E-2. (g) Same as f for significant tuning to correlated versus uncorrelated stimulations. ***Fisher exact P=6.1E-5. **P=8.2E-3 (364 neurons per bin). (h) Correlated stimulation-evoked mean Z-scores for all neurons, in normalized septal coordinate (444 neurons per bin). From left to right, equal neuron count bins contain neurons from area above barrel edge, septum edge and septum centre. **Mann–Whitney P=2.8E-3. (i) Same as h for the proportion of responsive correlation-preferring neurons over all cells. **Fisher exact P=2.2E-3 (444 neurons per bin).
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f2: A radial map of responses evoked by correlated (purple) versus uncorrelated stimulations (measured on the PW, green).(a) Z-score-derived correlated/uncorrelated stimulation preference index in an individual experiment. Marginal curves: example stimulus-triggered average calcium transients. Grey background: layer 4 barrel. White: septum. (b) Projection of Z-scores from a in normalized barrel radius coordinates. Lines: local Z-score median. (c) Projection in a normalized barrel of all recorded neurons. Colour code: Z-score-derived correlated/uncorrelated stimulation preference index. (d) Radial profile (364 neurons per bin) of mean correlated/uncorrelated stimulation-evoked dF/F, for all recorded neurons. Light background: bootstrap-derived 70% confidence interval. ***Mann–Whitney P=5.3E-4 for uncorrelated and 2.1E-6 for correlated stimulation-evoked responses. **P=2.0E-3. (e) Same as d for Z-scores. **Mann–Whitney P=2.1E-3 for uncorrelated and 3.6E-3 for correlated stimulation-evoked responses. ***Mann–Whitney P=5.0E-7. (f) Normalized radial profile (364 neurons per bin) of the proportion of neurons preferring correlated (purple) or uncorrelated (green) stimulations, among all responsive neurons. ***Fisher exact P=3.5E-9 for correlated and 1.9E-4 for uncorrelated stimulation-preferring neurons. **P=3.3E-2. (g) Same as f for significant tuning to correlated versus uncorrelated stimulations. ***Fisher exact P=6.1E-5. **P=8.2E-3 (364 neurons per bin). (h) Correlated stimulation-evoked mean Z-scores for all neurons, in normalized septal coordinate (444 neurons per bin). From left to right, equal neuron count bins contain neurons from area above barrel edge, septum edge and septum centre. **Mann–Whitney P=2.8E-3. (i) Same as h for the proportion of responsive correlation-preferring neurons over all cells. **Fisher exact P=2.2E-3 (444 neurons per bin).
Mentions: We then explored the spatial organization of neurons tuned to multi-whisker deflection statistics on top of the barrel map. In individual experiments, whereas responses to the PW during uncorrelated stimuli peaked above the centre of the corresponding barrel, responses to correlated stimulations were maximal in neurons at the periphery of barrels (Fig. 2a, Supplementary Fig. 4b–d and Supplementary Fig. 6). We confirmed this observation (Fig. 2b) by projecting the radial position of all neurons in a normalized radial space (Supplementary Fig. 7a). When data from all experiments were combined (Fig. 2c), we observed the same radial organization of the responses, considering either the mean amplitudes of the fluorescent transient (Fig. 2d), the mean Z-scores (Fig. 2e), the proportion of neurons preferring one of the two stimuli (Fig. 2f) or the proportion of neurons significantly selective to one of the two stimuli (Fig. 2g). These radial profiles produce a concentric map of relative responses to the two types of multi-whisker correlation stimuli (Fig. 2c).

View Article: PubMed Central - PubMed

ABSTRACT

In the barrel cortex, several features of single-whisker stimuli are organized in functional maps. The barrel cortex also encodes spatio-temporal correlation patterns of multi-whisker inputs, but so far the cortical mapping of neurons tuned to such input statistics is unknown. Here we report that layer 2/3 of the rat barrel cortex contains an additional functional map based on neuronal tuning to correlated versus uncorrelated multi-whisker stimuli: neuron responses to uncorrelated multi-whisker stimulation are strongest above barrel centres, whereas neuron responses to correlated and anti-correlated multi-whisker stimulation peak above the barrel–septal borders, forming rings of multi-whisker synchrony-preferring cells.

No MeSH data available.