Figure 8. Discrimination of familiar and novel oriented stimuli involves PV+ neurons in V1 and NMDAR expressed within PV+ neurons.

(A) Using the same protocol as described in Figure 3B, mice were progressively familiarized with a specific oriented stimulus. On the test day, as mice viewed familiar and novel stimuli, vidget behavioral responses were measured via a piezoelectric sensor located beneath the forepaws of the head-fixed mouse. (B) After a standard SRP protocol, mice expressing hM4D(Gi) receptors selectively within PV+ cells of binocular V1 were exposed to both familiar and novel stimuli. Prior to application of CNO, mice exhibited significant behavioral evidence of discriminating this familiar orientation from interleaved presentations of a novel oriented stimulus (black bars). After application of CNO, there was no longer successful discrimination of familiar and novel stimuli (red bars). Averaged vidget responses are displayed at the top of this panel. (C) A significant difference was observed in the ratio of response to familiar and novel stimuli from pre CNO (black) to post CNO (red). (D) A deficit in OSH was also apparent in PV GluN1 KO mice as vidget recordings demonstrated a failure to significantly discriminate familiar from novel orientations (gray bars). WT littermates exhibited significantly greater vidget magnitudes for novel than familiar stimuli, indicating unimpaired discrimination of familiarity from novelty (white bars). Averaged behavioral responses are displayed above with accompanying scale bars. (E) The significant deficit of PV GluN1 KO mice in discriminating familiar from novel stimuli is apparent in the ratio of behavior elicited by the familiar over the novel stimulus in comparison to WT littermates. Significant comparisons are marked with an asterisk throughout while non-significant comparisons are marked with n.s. Error bars are standard error of the mean (S.E.M.).

DOI: http://dx.doi.org/10.7554/eLife.11450.021

Figure 8—figure supplement 1. Cumulative distributions of average vidget behavioral response to familiar and novel stimuli for each individual animal included in analysis presented in Figure 8D and Figure 8E.

(A) Prior to CNO administration, average behavioral response to the familiar stimulus (light gray) and the novel stimulus (black) of each individual animal bilaterally expressing hM4D(Gi) in PV+ neurons of binocular V1. Dotted line represents behavior no greater than pre stimulus baseline. (B) Average behavioral response of the same animals to the familiar and a new novel stimulus during PV+ neuron inactivation via CNO delivery, revealing consequent deficit in discrimination of familiar and novel stimuli. (C) Cumulative distributions of average vidget behavioral response to the familiar stimulus (light gray) and the novel stimulus (black) of each individual WT GluN1 fl/fl mouse. (D) Average vidget behavioral response of each PV-GluN1 KO mouse to the familiar and a new novel stimulus, revealing deficit in discrimination of familiar and novel stimuli. Dotted line represents behavior no greater than pre stimulus baseline.

DOI: http://dx.doi.org/10.7554/eLife.11450.023