Behavioural Functions of Adult Neurogenesis
In my first postdoc with Dr. Jason Snyder at UBC in collaboration with Dr. Stan Floresco, I turned towards using innovative rat model systems in operant conditioning paradigms allowing me to investigate complex and translatable behaviours. Depression is a severe mental disorder with complex behavioural manifestations including disruptions in motivation, pleasure seeking, adaptive decision making, imagining future experiences, and valuing future rewards. Hippocampal neurogenesis is decreased in depressed human patients and conversely, some antidepressants act through increasing neurogenesis. To date, however, little work has thoroughly examined how a reduction in new neurons modulates the hippocampal network during behaviour. It is also not known, which of the complex behavioural traits of depression are actually caused by reductions in neurogenesis. My research shows that a loss of adult neurogenesis in rodents affects specific behavioural traits and cognition that are negatively affected in depression. I found that manipulation of adult neurogenesis by transgenic and chemogenetic approaches (DREADDs) affected decision-making for sugary rewards based on time, effort and probabilities; these are all behaviours disturbed in depression and other mood disorders.
