Adolescent mice exhibit lower reward sensitivity than adults

Area of Science:

• Neuroscience
• Developmental Psychology
• Behavioral Science

Background:

• Adolescence is marked by heightened social responsiveness and reward sensitivity, particularly in peer contexts.
• Neural circuits for social reward may develop differently from non-social reward circuits.
• Limited research explores reward processing across adolescent development, often focusing on single reward types, age groups, or sexes.

Purpose of the Study:

• To investigate how social, cocaine, and palatable food reward sensitivity changes during adolescent development in mice.
• To examine the association of different rewards with environmental contexts across developmental stages using conditioned place preference (CPP).

Main Methods:

• Utilized the conditioned place preference (CPP) paradigm in C57BL/6 mice.
• Compared reward sensitivity across early, mid, and late adolescence, and adulthood.
• Assessed social, cocaine, and palatable food rewards in both male and female mice.

Main Results:

• Adolescent mice showed lower preference for social and palatable food conditioned contexts.
• Cocaine CPP was not significantly affected by age.
• Age was the primary factor influencing CPP magnitude, with mid- and late-adolescents exhibiting reduced preference compared to adults.

Conclusions:

• Adolescent reward sensitivity does not universally enhance reward-context learning.
• Attenuated CPP in adolescence may reflect lower reward sensitivity in neutral conditions, not associative deficits.
• Developmental stage significantly influences reward behaviors, necessitating age- and sex-specific research.