Pubertal status associations with reward and threat sensitivities and subcortical brain volumes during adolescence

Abstract

Adolescence is characterized by complex developmental processes that impact behavior, biology, and social functioning. Two such adolescence-specific processes are puberty and increases in reward sensitivity. Relations between these processes are poorly understood. The present study focused on examining unique effects of puberty, age, and sex on reward and threat sensitivities and volumes of subcortical brain structures relevant for reward/threat processing in a healthy sample of 9-18year-olds. Unlike age, pubertal status had a significant unique positive relationship with reward sensitivity. In addition, there was a trend for adolescent females to exhibit higher threat sensitivity with more advanced pubertal development and higher reward and threat sensitivity with older age. Similarly, there were significant puberty by sex interaction effects on striatal volumes, i.e., left nucleus accumbens and right pallidum. The present pattern of results suggests that pubertal development, independent of chronological age, is uniquely associated with reward hypersensitivity and with structural differences in striatal regions implicated in reward processing.

Keywords: Adolescence; Behavioral approach system (BAS); Behavioral inhibition system (BIS); Puberty; Reward sensitivity.

Figure 1. Interaction effect of Pubertal Stage X Sex on left Nacc volumes corrected for total brain volume

The pattern of results suggests a decrease in the left Nacc volumes (corrected for total brain volume) for adolescent girls, and an increase for adolescent boys, with more advanced stages of pubertal development . Note that PCA puberty scores are derived from z-score transformations of the PDS and Tanner items, and as such, a value of 0 reflects the mean pubertal development for the sample, negative scores reflect less advanced pubertal development, and positive scores reflect relatively more advanced pubertal development. TBV = total brain volume.