Fig. 4

Distinct phases of social behavior in the SP and SNP tests. a Transitions, represented by blue dots, between stimuli during the SP test. Each line represents one mouse (45 males), and the red line represents the mean of all mice averaged within 20-s bins. b Investigation time (mean + SEM within 1-min bins) across the SP test when short bouts (< 6 s) are separately analyzed. c As in b, for long investigation bouts (> 19 s). A significant difference was found between social and object stimuli (post hoc t test following main effect). d Plot of mean investigation time (measured within 20-s bins) across the SNP session for male mice (n = 45) using meshed chambers. e Distribution of mean total investigation time (+SEM) according to bout duration, for both social stimuli. A significant difference between the familiar and novel stimuli was observed only for bouts which are longer than 6 s (post hoc t test following main effect). f As in a, for the SNP test. g As in b, for the SNP test. h As in c, for the SNP test. A significant difference was found between the stimuli (post hoc t test following main effect)