Monoamine neurons have unique activity patterns that modulate animal behavior. They can perform high-order computations, such as gated feedback and reward predictions, at a fast timescale. They also show a persistent increase or decrease in tonic activity, which can trigger, for example, mood changes.
As therapeutic drugs for brain disorders act on monoamine systems, basic understandings of their working principles are important. Yet, how these neurons integrate excitatory, inhibitory and other inputs to shape their activity patterns has been difficult to examine, because in mammals, monoamine neurons only exist in deep loci of the brain. We use zebrafish, which have conserved monoaminergic systems in their transparent brain, to tackle this issue. Specifically, we employ genetically-encoded voltage and neurotransmitter indicators to investigate how monoaminergic neurons integrate information in their subcellular compartments during adaptive behaviors.
 Kawashima*, Wei* et al.
"The role of the serotonergic system in motor control"
Neuroscience Research. 129: 32-39 (2018)
 Abdelfattah*, Kawashima* et al.
"Bright and photostable chemigenetic indicators for extended in vivo voltage imaging"
Science. 365 (6454): 699-704 (2019)
 Marvin et al.
"A genetically encoded fluorescent sensor for in vivo imaging of GABA"
Nature Methods. 16:763–770 (2019)