Role of an identified looming-sensitive neuron in triggering a flying locust's escape

Authors: Santer, R.D., Rind, F.C., Stafford, R. and Simmons, P.J.

Journal: Journal of Neurophysiology

Volume: 95

Issue: 6

Pages: 3391-3400

ISSN: 0022-3077

DOI: 10.1152/jn.00024.2006

Abstract:

Flying locusts perform a characteristic gliding dive in response to predatorsized stimuli looming from one side. These visual looming stimuli trigger trains of spikes in the descending contralateral movement detector (DCMD) neuron that increase in frequency as the stimulus gets nearer. Here we provide evidence that high-frequency (>150 Hz) DCMD spikes are involved in triggering the glide: the DCMD is the only excitatory input to a key gliding motor neuron during a loom; DCMD-mediated EPSPs only summate significantly in this motor neuron when they occur at >150 Hz; when a looming stimulus ceases approach prematurely, high-frequency DCMD spikes are removed from its response and the occurrence of gliding is reduced; and an axon important for glide triggering descends in the nerve cord contralateral to the eye detecting a looming stimulus, as the DCMD does. DCMD recordings from tethered flying locusts showed that glides follow high-frequency spikes in a DCMD, but analyses could not identify a feature of the DCMD response alone that was reliably associated with glides in all trials. This was because, for a glide to be triggered, the high-frequency spikes must be timed appropriately within the wingbeat cycle to coincide with wing elevation. We interpret this as flight-gating of the DCMD response resulting from rhythmic modulation of the flight motor neuron's membrane potential during flight. This means that the locust's escape behavior can vary in response to the same looming stimulus, meaning that a predator cannot exploit predictability in the locust's collision avoidance behavior. Copyright © 2006 The American Physiological Society.

Source: Scopus

Role of an identified looming-sensitive neuron in triggering a flying locust's escape.

Authors: Santer, R.D., Rind, F.C., Stafford, R. and Simmons, P.J.

Journal: J Neurophysiol

Volume: 95

Issue: 6

Pages: 3391-3400

ISSN: 0022-3077

DOI: 10.1152/jn.00024.2006

Abstract:

Flying locusts perform a characteristic gliding dive in response to predator-sized stimuli looming from one side. These visual looming stimuli trigger trains of spikes in the descending contralateral movement detector (DCMD) neuron that increase in frequency as the stimulus gets nearer. Here we provide evidence that high-frequency (>150 Hz) DCMD spikes are involved in triggering the glide: the DCMD is the only excitatory input to a key gliding motor neuron during a loom; DCMD-mediated EPSPs only summate significantly in this motor neuron when they occur at >150 Hz; when a looming stimulus ceases approach prematurely, high-frequency DCMD spikes are removed from its response and the occurrence of gliding is reduced; and an axon important for glide triggering descends in the nerve cord contralateral to the eye detecting a looming stimulus, as the DCMD does. DCMD recordings from tethered flying locusts showed that glides follow high-frequency spikes in a DCMD, but analyses could not identify a feature of the DCMD response alone that was reliably associated with glides in all trials. This was because, for a glide to be triggered, the high-frequency spikes must be timed appropriately within the wingbeat cycle to coincide with wing elevation. We interpret this as flight-gating of the DCMD response resulting from rhythmic modulation of the flight motor neuron's membrane potential during flight. This means that the locust's escape behavior can vary in response to the same looming stimulus, meaning that a predator cannot exploit predictability in the locust's collision avoidance behavior.

Source: PubMed

Role of an identified looming-sensitive neuron in triggering a flying locust's escape

Authors: Santer, R.D., Rind, F.C., Stafford, R. and Simmons, P.J.

Journal: JOURNAL OF NEUROPHYSIOLOGY

Volume: 95

Issue: 6

Pages: 3391-3400

ISSN: 0022-3077

DOI: 10.1152/jn.00024.2006

Source: Web of Science (Lite)

Role of an identified looming-sensitive neuron in triggering a flying locust's escape

Authors: Santer, R.D., Rind, F.C., Stafford, R. and Simmons, P.J.

Journal: Journal of Neurophysiology

Volume: 95

Pages: 3391-3400

ISSN: 0022-3077

DOI: 10.1152/jn.00024.2006

Source: Manual

Preferred by: Rick Stafford

Role of an identified looming-sensitive neuron in triggering a flying locust's escape.

Authors: Santer, R.D., Rind, F.C., Stafford, R. and Simmons, P.J.

Journal: Journal of neurophysiology

Volume: 95

Issue: 6

Pages: 3391-3400

eISSN: 1522-1598

ISSN: 0022-3077

DOI: 10.1152/jn.00024.2006

Abstract:

Flying locusts perform a characteristic gliding dive in response to predator-sized stimuli looming from one side. These visual looming stimuli trigger trains of spikes in the descending contralateral movement detector (DCMD) neuron that increase in frequency as the stimulus gets nearer. Here we provide evidence that high-frequency (>150 Hz) DCMD spikes are involved in triggering the glide: the DCMD is the only excitatory input to a key gliding motor neuron during a loom; DCMD-mediated EPSPs only summate significantly in this motor neuron when they occur at >150 Hz; when a looming stimulus ceases approach prematurely, high-frequency DCMD spikes are removed from its response and the occurrence of gliding is reduced; and an axon important for glide triggering descends in the nerve cord contralateral to the eye detecting a looming stimulus, as the DCMD does. DCMD recordings from tethered flying locusts showed that glides follow high-frequency spikes in a DCMD, but analyses could not identify a feature of the DCMD response alone that was reliably associated with glides in all trials. This was because, for a glide to be triggered, the high-frequency spikes must be timed appropriately within the wingbeat cycle to coincide with wing elevation. We interpret this as flight-gating of the DCMD response resulting from rhythmic modulation of the flight motor neuron's membrane potential during flight. This means that the locust's escape behavior can vary in response to the same looming stimulus, meaning that a predator cannot exploit predictability in the locust's collision avoidance behavior.

Source: Europe PubMed Central