Parallel descending neurons differentially encode target and looming information in the hoverfly visual system
- 1Flinders University
Abstract
Detecting small, fast-moving objects is crucial for behaviors such as pursuit, territorial defence, and predator avoidance. At long range, however, potential mates, rivals, and predators produce remarkably similar visual signals, potentially making them difficult to distinguish. Nevertheless, many flying insects, including the hoverfly Eristalis tenax, can respond rapidly and appropriately to these ambiguous visual cues, implying specialised neural pathways that extract behaviorally relevant information. Descending neurons link visual processing to motor output, thus transforming visual signals into behavioral actions. In E. tenax, both target selective descending neurons (TSDNs) and looming-sensitive descending neurons respond to small targets, yet their respective contributions to target processing remain unclear. Using electrophysiological recordings, we compared receptive field organization and sensitivity to target size and motion direction across these neuronal populations. Although TSDNs and looming-sensitive descending neurons differed systematically in their target coding, a subset of looming-sensitive descending neurons closely resembled TSDNs, sharing small receptive fields and sharp target tuning despite retaining sensitivity to looming stimuli. These findings reveal previously unrecognized diversity among descending neurons tuned to small targets and suggest that parallel descending pathways encode distinct information from similar visual cues. Such an organization may enable common visual inputs to support both target pursuit and the detection of approaching threats.
Related
- Anterior cingulate neurons perform parallel processing of fixated and peripheral information to guide information sampling and choice
- Synaptic placement reflects shared input in Drosophila descending neurons
- Two parallel lateral hypothalamic GABAergic projections differentially modulate pain and anxiety in mice
- A NEST-based framework unlocks massively parallel simulation of networks of multi-compartment neurons with customizable subcellular dynamics
- Frequency-specific oscillations track parallel processing of linguistic structural and lexical-semantic information from perception to decision
BibTeX
@misc{nicholas2026parallel,
title = {{Parallel descending neurons differentially encode target and looming information in the hoverfly visual system}},
author = {S. Nicholas and K. Nordstrom},
howpublished = {bioRxiv},
year = {2026},
month = nov,
doi = {10.64898/2026.11.04.764150},
url = {https://www.biorxiv.org/content/10.64898/2026.11.04.764150v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - Parallel descending neurons differentially encode target and looming information in the hoverfly visual system
AU - S. Nicholas
AU - K. Nordstrom
PY - 2026
DA - 2026/11/04
PB - bioRxiv
DO - 10.64898/2026.11.04.764150
UR - https://www.biorxiv.org/content/10.64898/2026.11.04.764150v1
AB - Detecting small, fast-moving objects is crucial for behaviors such as pursuit, territorial defence, and predator avoidance. At long range, however, potential mates, rivals, and predators produce remarkably similar visual signals, potentially making them difficult to distinguish. Nevertheless, many flying insects, including the hoverfly Eristalis tenax, can respond rapidly and appropriately to these ambiguous visual cues, implying specialised neural pathways that extract behaviorally relevant information. Descending neurons link visual processing to motor output, thus transforming visual signals into behavioral actions. In E. tenax, both target selective descending neurons (TSDNs) and looming-sensitive descending neurons respond to small targets, yet their respective contributions to target processing remain unclear. Using electrophysiological recordings, we compared receptive field organization and sensitivity to target size and motion direction across these neuronal populations. Although TSDNs and looming-sensitive descending neurons differed systematically in their target coding, a subset of looming-sensitive descending neurons closely resembled TSDNs, sharing small receptive fields and sharp target tuning despite retaining sensitivity to looming stimuli. These findings reveal previously unrecognized diversity among descending neurons tuned to small targets and suggest that parallel descending pathways encode distinct information from similar visual cues. Such an organization may enable common visual inputs to support both target pursuit and the detection of approaching threats.
ER -