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Data from: Persistent firing and adaptation in optic-flow-sensitive descending neurons

Citation

Nordström, Karin; Nicholas, Sarah (2020), Data from: Persistent firing and adaptation in optic-flow-sensitive descending neurons, Dryad, Dataset, https://doi.org/10.5061/dryad.fbg79cnr9

Abstract

A general principle of sensory systems is that they adapt to prolonged stimulation by reducing their response over time. Indeed, in many visual systems, including higher-order motion sensitive neurons in the fly optic lobes and the mammalian visual cortex, a reduction in neural activity following prolonged stimulation occurs. In contrast to this phenomenon, the response of the motor system controlling flight maneuvers persists following the offset of visual motion. It has been suggested that this gap is caused by a lingering calcium signal in the output synapses of optic lobe neurons. However, whether this directly affects the responses of the post-synaptic descending neurons, leading to the observed behavioral output, is not known. We use extracellular electrophysiology to record from optic flow sensitive descending neurons in response to prolonged wide-field stimulation. We find that, as opposed to most sensory and visual neurons, and in particular to the motion vision sensitive neurons in the brains of flies and mammals, the descending neurons show little adaption during stimulus motion. In addition, we find that the optic flow sensitive descending neurons display persistent firing, or an after-effect, following the cessation of visual stimulation, consistent with the lingering calcium signal hypothesis. However, if the difference in after-effect is compensated for, subsequent presentation of stimuli in a test-adapt-test paradigm reveals adaptation to visual motion. Our results thus show a combination of adaptation and persistent firing, in the neurons that project to the thoracic ganglia, and thereby control behavioral output.

Methods

Extracellular electrophysiology of descending neurons in the hoverfly Eristalis Tenax.

Funding

U.S. Air Force, Award: FA9550-19-1-0294

Australian Research Council, Award: DP180100144

Australian Research Council, Award: DP170100008

Australian Research Council, Award: FT180100289

Flinders Foundation