Data for: Inhibition drives habituation of a larval zebrafish visual response

Habituation allows animals to learn to ignore persistent but
inconsequential stimuli. Despite being the most basic form of learning, a
consensus model on the underlying mechanisms has yet to emerge. To probe
relevant mechanisms we took advantage of a visual habituation paradigm in
larval zebrafish, where larvae reduce their reactions to abrupt global
dimming (a dark flash). Using Ca2+ imaging during repeated dark flashes,
we identified 12 functional classes of neurons that differ based on their
rate of adaptation, stimulus response shape, and anatomical location.
While most classes of neurons depressed their responses to repeated
stimuli, we identified populations that did not adapt, or that potentiated
their response. To identify molecular players, we used a small
molecule-screening approach to search for compounds that alter habituation
learning. Among the pathways we identified were Melatonin and Estrogen
signaling, as well as GABAergic inhibition. By analyzing which functional
classes of neurons are GABAergic, and the result of pharmacological
manipulations of the circuit, we propose that GABAergic inhibitory motifs
drive habituation, perhaps through the potentiation of GABAergic synapses.
Our results have identified multiple molecular pathways and cell types
underlying a form of long-term plasticity in a vertebrate brain, and allow
us to propose the first iteration of a model for how and where this
learning process occurs.