Figure 3.

Neural activity associated with the helping behavior test

The Brain-wide pattern of neural activity was determined by age and group identity.

(A) Diagram of brain regions sampled for c-Fos expression.

(B) A representative image of c-Fos signal sampled in the piriform cortex.

(C) Legend of brain region categories coded by color.

(D) Number of c-Fos + cells per region (mean ± SEM). Significant latent variables reveal that group identity (E) and age (F) determine neural activity patterns. The salience represents the z-score of boot-strapping tests, with regions crossing the black threshold lines significantly (p < 0.01) contributing to the contrast depicted in the inset (black bars). The directionality of the bars is congruent with the contrast graphs, as demonstrated by the arrows along the y axis. All regions were more active for ingroup than outgroup members, but several regions (e.g., VO) were more active for adolescent rats than adult rats. See also Figure S1 for detailed scatterplots of each region.