Dopamine, Reward Learning and Sex Hormones

Summary

Hormonal transition periods during the menstrual cycle may predispose women to mental disorders. Hormonal fluctuations provide specific neuroendocrine conditions that modulate brain structure and function and these actions affect cognitive and emotional behaviors and affect energy and mood homeostasis. It is thought that these changes are driven by altered dopamine transmission. Here, the investigators aim to examine (1) how sex hormones and dopamine are linked and also (2) how hormonal changes affect motivation, mood, and energy homeostasis. To this end, dopamine intervention will be tested on effort-based decision-making and motivational circuits in three hormonal stages (i.e., women in early-follicular phase (EF), women in mid-luteal phase (ML), and men). Additionally, the effects of hormonal status on metabolic indices will be tested, and its effects on mood fluctuations in a period of a month. The investigator hypothesizes that women in EF cycle phase (1) have naturally less dopamine and show less effort, and (2) they show greater improvement in effort-based decision-making after Levodopa administration. The investigator has exploratory outcomes about (3) sex differences in reward-learning with and without Levodopa administration and explores if these differences correlate with elevated female sex hormone levels. Moreover, it is hypothesized that (4) hormonal fluctuations affect energy homeostasis, thus women in their EF cycle phase have higher energy expenditure and (5) they report more negative mood than in their mid-luteal (ML) cycle phase.

Timeline

Start

2024-05

Primary completion

2025-12

Completion

2025-12

Drugs

Indications