Neurobehavioral evidence for changes in dopamine system activity during adolescence

Abstract

Human adolescence has been characterized by increases in risk-taking, emotional lability, and deficient patterns of behavioral regulation. These behaviors have often been attributed to changes in brain structure that occur during this developmental period, notably alterations in gray and white matter that impact synaptic architecture in frontal, limbic, and striatal regions. In this review, we provide a rationale for considering that these behaviors may be due to changes in dopamine system activity, particularly overactivity, during adolescence relative to either childhood or adulthood. This rationale relies on animal data due to limitations in assessing neurochemical activity more directly in juveniles. Accordingly, we also present a strategy that incorporates molecular genetic techniques to infer the status of the underlying tone of the dopamine system across developmental groups. Implications for the understanding of adolescent behavioral development are discussed.

Feedback Processing in Adolescence: An Event-Related Potential Study of Age and Gender Differences

“…Frank [44] and Frank and Claus [45] have suggested that phasic increases in DA that occur in response to positive feedback are related to D 1 receptor activity while decreases in DA after negative feedback are related to D 2 activity. If this is so, then the gender- and age-related differences that we have reported in the FRN can be mapped onto the sexual dimorphism seen in DA activity, DA receptor density and DA system maturation [22,23,46]. DA system changes during adolescence are more dramatic for males than females [22,23], and adult males have more D 1 receptors in the ventral striatum than females [47].…”

“…These reports are consistent with our finding that the FRN in males but not females is sensitive to the size of the win. Furthermore, D 2 receptor maturation begins and ends later than D 1 receptors and, if changes are more profound for males than females [46], this may explain why the FRN to losses seems markedly immature in boys compared to girls. …”

Reward sensitivity is associated with brain activity during erotic stimulus processing

“…Finally, these values were included in a partial correlation with SR scores, removing the effect of age. We included age as a covariate because previous evidence has shown that this variable is related to brain activity within the dopaminergic system [40,41]. The correlation analysis threshold was set to p,.05 Bonferroni FWE corrected.…”

Aging magnifies the effects of dopamine transporter and D2 receptor genes on backward serial memory

“…Of particular relevance for the current study, intermediate phenotypes, such as brain mechanisms at neurochemical, structural, and functional levels (Meyer-Lindenberg and Weinberger, 2006), change substantially during maturation and senescence. Thus, it has been hypothesized that age-related differences in brain resources might modulate genotype-phenotype relations during different life periods Posner et al, 2006;Wahlstrom et al, 2010). Genes related to the neurotransmitter dopamine (DA) represent a case in point.…”