title: The Serotonergic System Tracks the Outcomes of Actions to Mediate Short-Term Motor Learning.
abstract: To execute accurate movements, animals must continuously adapt their behavior to changes in their bodies and environments. Animals can learn changes in the relationship between their locomotor commands and the resulting distance moved, then adjust command strength to achieve a desired travel distance. It is largely unknown which circuits implement this form of motor learning, or how. Using whole-brain neuronal imaging and circuit manipulations in larval zebrafish, we discovered that the serotonergic dorsal raphe nucleus (DRN) mediates short-term locomotor learning. Serotonergic DRN neurons respond phasically to swim-induced visual motion, but little to motion that is not self-generated. During prolonged exposure to a given motosensory gain, persistent DRN activity emerges that stores the learned efficacy of motor commands and adapts future locomotor drive for tens of seconds. The DRN's ability to track the effectiveness of motor intent may constitute a computational building block for the broader functions of the serotonergic system. VIDEO ABSTRACT.
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, 19700 Helix Drive, Ashburn, VA 20147, USA.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawashima
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, 19700 Helix Drive, Ashburn, VA 20147, USA.
authors.forename: Maarten F
authors.initials: MF
authors.lastname: Zwart
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, 19700 Helix Drive, Ashburn, VA 20147, USA.
authors.forename: Chao-Tsung
authors.initials: CT
authors.lastname: Yang
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, 19700 Helix Drive, Ashburn, VA 20147, USA.
authors.forename: Brett D
authors.initials: BD
authors.lastname: Mensh
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, 19700 Helix Drive, Ashburn, VA 20147, USA. Electronic address: ahrensm@janelia.hhmi.org.
authors.forename: Misha B
authors.initials: MB
authors.lastname: Ahrens
mesh_terms: D000818:Animals; D001931:Brain Mapping; D007814:Larva; D007858:Learning; D008959:Models, Neurological; D062308:Optogenetics; D011903:Raphe Nuclei / Q000502:physiology; D059326:Serotonergic Neurons / Q000166:cytology / Q000502:physiology; D065855:Spatial Processing; D013550:Swimming; D015027:Zebrafish / Q000502:physiology*
keywords: dorsal raphe nucleus; imaging; motor learning; neural circuits; neuromodulation; neuroscience; serotonergic system; serotonin; short-term memory; zebrafish