Control of visually guided behavior by distinct populations of spinal projection neurons.
A basic question in the field of motor control is how different actions are represented by activity in spinal projection neurons. We used a new behavioral assay to identify visual stimuli that specifically drive basic motor patterns in zebrafish. These stimuli evoked consistent patterns of neural activity in the neurons projecting to the spinal cord, which we could map throughout the entire population using in vivo two-photon calcium imaging. We found that stimuli that drive distinct behaviors activated distinct subsets of projection neurons, consisting, in some cases, of just a few cells. This stands in contrast to the distributed activation seen for more complex behaviors. Furthermore, targeted cell by cell ablations of the neurons associated with evoked turns abolished the corresponding behavioral response. This description of the functional organization of the zebrafish motor system provides a framework for identifying the complete circuit underlying a vertebrate behavior.
Orger
Michael B
MB
Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA. morger@mcb.harvard.edu
Kampff
Adam R
AR
Severi
Kristen E
KE
Bollmann
Johann H
JH
Engert
Florian
F
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001369:Axons / Q000502:physiology / Q000648:ultrastructure; D001933:Brain Stem / Q000033:anatomy & histology / Q000502:physiology*; D002118:Calcium / Q000737:chemistry; D003714:Denervation; D004525:Efferent Pathways / Q000033:anatomy & histology / Q000502:physiology; D005456:Fluorescent Dyes; D007839:Functional Laterality / Q000502:physiology; D007202:Indicators and Reagents; D008124:Locomotion / Q000502:physiology; D023421:Models, Animal; D009415:Nerve Net / Q000166:cytology / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D009949:Orientation / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*; D012154:Reticular Formation / Q000033:anatomy & histology / Q000502:physiology*; D013116:Spinal Cord / Q000033:anatomy & histology / Q000502:physiology*; D013194:Staining and Labeling; D013550:Swimming / Q000502:physiology; D014795:Visual Pathways / Q000502:physiology; D015027:Zebrafish / Q000033:anatomy & histology / Q000502:physiology*
D005456:Fluorescent Dyes; D007202:Indicators and Reagents; D002118:Calcium