Sun. Oct 13, 2019 2:50 PM - 4:30 PM Room 4 (409)

Organizer / Chair: Satoshi KIDA (Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan), Co-chair: Masamichi SAKAGAMI (Brain Science Institute, Tamagawa University, Japan), Discussants: ‌Ayako WATABE (Institute of Clinical Medicine and Research, Jikei Univeristy School of Medicine, Japan), Hotaka FUKUSHIMA (Department of Bioscience, Faculty of Life Sciences, Tokyo University of Agriculture, Japan)

Recent technological breakthroughs for manipulating and recording the activity of specific cell populations in defined circuits have resulted in dramatic advances in our understanding of the brain mechanisms mediating learning and memory that is modulated by emotion, decision making and so on. In parallel, a large amount of work has demonstrated that monoamines such as serotonin and dopamine play key modulatory roles in the regulation of emotion and learning and memory. However, our understanding remains incomplete, and central questions remain as to how monoamines regulate various forms of learning and memory and how these effects may become disrupted in pathological states. In this symposium, we bring together investigators who have approached these questions from different directions. The objective of the symposium is to introduce cutting edge studies investigating mechanisms for regulation of learning and memory by monoamines at the molecular, cellular and circuits levels. Balleine will present experiments investigating the role of dopamine signaling in the dorsomedial striatum in the acquisition of goal-directed actions, particularly as it relates to learning-related plasticity in direct and indirect pathway medium spiny neurons. Holmes will discuss recent findings showing that discrete serotonin circuits deferentially modulate the formation of aversive memories and risky decision-making, and discuss pharmacological data showing how these circuit-level effects require signaling through distinct 5-HT receptor subtypes. Kida will discuss roles of hippocampal dopamine signals in retrieval of memory – showing that hippocampal circadian clock regulates retrieval of hippocampus-dependent memory via signal transduction composed of Dopamine-D1/D5R-cAMP-PKA-AMPA receptor GluA1 phosphorylation at S845.