HDR defense – Céline Nicolas

My research focuses on understanding the behavioral and neurobiological mechanisms underlying drug addiction, with a particular interest in relapse vulnerability. During my thesis, I studied how environmental factors influence drug relapse vulnerability. In rats, I identified, specific long-lasting metabolic brain changes during cocaine abstinence in neurocircuits involved in reward, motivation, salience and stress. Moreover, I demonstrated that the interactions with positive environmental stimuli during abstinence protects against drug relapse by modulating brain regions involved in stress-related behaviors. During my post-doctoral work, I studied how internal biological factors, such as sex and ovarian hormones could play a role in drug relapse vulnerability. I demonstrated that incubation of cocaine craving was higher in female than male rats, an effect dependent on the estrous cycle. Additionally, I identified a sexually dimorphic coding and causal role of the insular cortex in persistent alcohol drinking despite aversion in mice. My current research projects focus on identifying and understanding fundamental behavioral principles and the hormonal and neuronal circuit mechanisms involved in sex differences in drug addiction.