A model of the locust visual system under diverse stimuli highlights functionality of various mechanisms and suggests a parsimonious structure
- 1University of Saskatchewan Department of Biology
Abstract
Locusts possess a collision-sensitive pathway in their visual system culminating in a neuron, the lobula giant movement detector (LGMD), which preferentially responds to looming stimuli. The LGMD is also notable for its reduced or absent response to other stimuli, such as translating objects, wide-field motion, and incoherent images of looming objects. While experimental and modelling work have both shed light on the various mechanisms underpinning these properties, broad examinations of how these mechanisms interact with each other and with diverse stimulus types have been limited. To address this, we developed a model incorporating mechanisms from recent literature, and subjected to an array of looming stimuli with varying size-to-speed ratio, polarity (OFF and ON), and coherence; wide-field background motion, translating stimuli, and trajectory changes were also examined. The model showed quantitative and qualitative fidelity to biological data in its replication of a wide variety of stimulus responses, with its preference for incoherent visual stimuli being a notable exception. Based on investigations with various inhibition types removed, it was shown that lateral inhibition predominantly suppressed wide-field motion responses. Global inhibition both normalized growing excitation over the course of looming, and improved recognition of looming stimuli against moving backgrounds. Feedforward inhibition was found to have diverse roles, including shaping peak response time and its variability, and improving coherence selectivity. The success of the model in replicating multiple stimuli also showed the plausibility of several underlying assumptions, including sharing of input between the LGMD and multiple other neuron types.
Related
- Gene expression in Anolis sagrei suggests conservation of patterning mechanisms drives formation of two high acuity areas
- A transcriptional atlas of early Arabidopsis seed development suggests mechanisms for inter-tissue coordination
- Modulation of bioactive composition and color functionality of copigmented blueberry anthocyanins encapsulated by spray drying: Effect of copigment structure and ratio
- Transcriptomic and phenotypic characterization of Alzheimer's disease risk genes in neurons and astrocytes highlights shared and cell type specific cellular mechanisms
- Repurposing Regulatory Rodent Toxicology Safety Archives to Identify Candidate Hormetic Longevity Agents Highlights Emergent Mitochondrial Mechanisms.
BibTeX
@misc{olson2026model,
title = {{A model of the locust visual system under diverse stimuli highlights functionality of various mechanisms and suggests a parsimonious structure}},
author = {E. G. N. Olson and T. K. Wiens and J. R. Gray},
howpublished = {bioRxiv},
year = {2026},
month = sep,
doi = {10.64898/2026.09.14.751446},
url = {https://www.biorxiv.org/content/10.64898/2026.09.14.751446v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - A model of the locust visual system under diverse stimuli highlights functionality of various mechanisms and suggests a parsimonious structure
AU - E. G. N. Olson
AU - T. K. Wiens
AU - J. R. Gray
PY - 2026
DA - 2026/09/14
PB - bioRxiv
DO - 10.64898/2026.09.14.751446
UR - https://www.biorxiv.org/content/10.64898/2026.09.14.751446v1
AB - Locusts possess a collision-sensitive pathway in their visual system culminating in a neuron, the lobula giant movement detector (LGMD), which preferentially responds to looming stimuli. The LGMD is also notable for its reduced or absent response to other stimuli, such as translating objects, wide-field motion, and incoherent images of looming objects. While experimental and modelling work have both shed light on the various mechanisms underpinning these properties, broad examinations of how these mechanisms interact with each other and with diverse stimulus types have been limited. To address this, we developed a model incorporating mechanisms from recent literature, and subjected to an array of looming stimuli with varying size-to-speed ratio, polarity (OFF and ON), and coherence; wide-field background motion, translating stimuli, and trajectory changes were also examined. The model showed quantitative and qualitative fidelity to biological data in its replication of a wide variety of stimulus responses, with its preference for incoherent visual stimuli being a notable exception. Based on investigations with various inhibition types removed, it was shown that lateral inhibition predominantly suppressed wide-field motion responses. Global inhibition both normalized growing excitation over the course of looming, and improved recognition of looming stimuli against moving backgrounds. Feedforward inhibition was found to have diverse roles, including shaping peak response time and its variability, and improving coherence selectivity. The success of the model in replicating multiple stimuli also showed the plausibility of several underlying assumptions, including sharing of input between the LGMD and multiple other neuron types.
ER -