Molecular psychiatrySep 15, 2025

Aging lowers motivation by reducing brain growth factor in the brain’s reward area

Longevity & Aging Weekly Brief ↗PubMed ↗DOI ↗OA ↗

Updated Jun 27, 2026

Abstract

Essence

Aging-related loss of Bdnf in the ventral tegmental area may contribute to reduced motivation in mice.

Evidence

This was a mouse-model study comparing young, old, and socially isolated mice, with VTA-specific Bdnf knockdown in young mice used to test whether reduced Bdnf recapitulates aging-associated motivational decline.

Caveat

The evidence is limited to mouse behavioral and gene-expression models and does not establish effects on human aging or neuropsychiatric disorders.

Simplified

Age-associated reduced motivation is a hallmark of neuropsychiatric disorders in the elderly. In our rapidly aging societies, it is critical to keep motivation levels high enough to promote healthspan and lifespan. However, how motivation is reduced during aging remains unknown. Here, we used multiple mouse models to evaluate motivation and related affective states in young and old mice. We also compared the effect of social isolation, a common stressor in aged populations, to those of aging. We found that both social isolation and aging decreased motivation in mice, but that Bdnf expression in the ventral tegmental area (VTA) was selectively decreased during aging. Furthermore, VTA-specific Bdnf knockdown in young mice recapitulated reduced motivation observed in old mice. These results demonstrate that maintaining Bdnf expression in the VTA could promote motivation to engage in effortful activities and potentially prevent age-associated neuropsychiatric disorders.