I presented my most recent findings on how TrkB inhibition influences odour habituation behaviour. Had a wonderful time chatting with fellow scientists about olfactory memory. Thanks to all for suggestions and research ideas. I'm working on a couple right now. Publications forthcoming.
The role of BDNF-TrkB signaling in olfactory bulb-dependent olfactory memory.
Abstract: Understanding the molecular mechanisms underlying short-term (STM) and long-term memory (LTM) has been a long-standing goal in neuroscience. Many putative forms of cellular LTM (including long-term plasticity and adult neurogenesis; Korte et al., 1995, PNAS; Scharfman et al., 2005, Exp Neurology) have been shown to depend on brain-derived neurotrophic factor (BDNF). One-trial fear-based memories additionally have been shown to rely on specific temporal peaks of BDNF activity induced after learning (Bekinschtein et al., 2007, Neuron). However, the role(s) and timecourse of BDNF activity in multi-trial appetitive learning is unclear. We used olfactory bulb (OB)-dependent learning tasks to investigate the role of the BDNF-TrkB pathway in STM and LTM mechanisms. First, we examined whether odour-reward memories depend on TrkB-mediated BDNF activity in the OB. Adult mice were trained over several trials to learn an odour-reward association and memory was tested 2 or 48 hours later. Compared to controls, mice infused with OB infusions of the BDNF receptor antagonist, K252a, showed normal 2-hour memory, but impaired memory at 48 hours. This finding suggests that early activation of the BDNF-TrkB pathway is necessary for the consolidation of OB-dependent LTM, but not STM. Next, using an olfactory generalization task, we investigated whether LTM memory deficits on the odour-reward task are the result of disrupted odour memory representations. Finally, using RT-qPCR, we are mapping the timecourse of activity for bdnf and other plasticity-related proteins across multiple brain areas for incrementally-acquired olfactory memories.