Correlation between OFF and ON Channels Underlies Dark Target Selectivity in an Insect Visual System

Wiederman, Steven D.; Shoemaker, Patrick A.; O’Carroll, David C.

doi:10.1523/jneurosci.1277-13.2013

Cited by 53 publications

(60 citation statements)

References 41 publications

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“…Small target motion detectors (STMDs) examined to date in the dragonfly [31] and hoverfly [3] show preference for objects darker than the background. We therefore presented a light object moving across a dark background (ON) and dark object moving on a light background (OFF) (Figure 3A).…”

Section: Resultsmentioning

confidence: 99%

Object-Detecting Neurons in Drosophila

2017

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SUMMARY Many animals rely on vision to detect objects such as conspecifics, predators, and prey. Hypercomplex cells found in feline cortex and small target motion detectors found in dragonfly and hoverfly optic lobes demonstrate robust tuning for small objects with weak or no response to larger objects or movement of the visual panorama [1–3]. However, the relationship between anatomical, molecular, and functional properties of object detection circuitry is not understood. Here, we characterize a specialized object detector in Drosophila, the lobula columnar neuron LC11 [4]. By imaging calcium dynamics with two-photon excitation microscopy we show that LC11 responds to the omni-directional movement of a small object darker than the background, with little or no responses to static flicker, vertically elongated bars, or panoramic gratings. LC11 dendrites innervate multiple layers of the lobula, and each dendrite spans enough columns to sample 75-degrees of visual space, yet the area that evokes calcium responses is only 20-degrees wide, and shows robust responses to a 2.2-degree object spanning less than half of one facet of the compound eye. The dendrites of neighboring LC11s encode object motion retinotopically, but the axon terminals fuse into a glomerular structure in the central brain where retinotopy is lost. Blocking inhibitory ionic currents abolishes small object sensitivity and facilitates responses to elongated bars and gratings. Our results reveal high acuity object motion detection in the Drosophila optic lobe.

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Section: Resultsmentioning

confidence: 99%

Object-Detecting Neurons in Drosophila

2017

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“…The ESTMD model reliably predicts several properties of STMD neurons, including their spatio-temporal tuning, their rejection of background motion [12] and even the selectivity for dark targets seen in some STMDs [13]. However, this remains a model only for the elementary operation of local target discrimination: it makes no attempt to account for how information integrated across a large visual field is used to control visual gaze or target pursuit.…”

Section: Introductionmentioning

confidence: 99%

“…Indeed, many STMD neurons are selective for the direction of target movement [6,10,14]. (2) The ESTMD model and some STMD neurons are selective for the polarity of target contrast [13]. Yet insects pursue targets against variable backgrounds, thus requiring a mechanism to track targets independent of their relative luminance.…”

Section: Introductionmentioning

confidence: 99%

Properties of neuronal facilitation that improve target tracking in natural pursuit simulations

Bagheri

Wiederman

Cazzolato

et al. 2015

J. R. Soc. Interface.

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Although flying insects have limited visual acuity (approx. 18) and relatively small brains, many species pursue tiny targets against cluttered backgrounds with high success. Our previous computational model, inspired by electrophysiological recordings from insect 'small target motion detector' (STMD) neurons, did not account for several key properties described from the biological system. These include the recent observations of response 'facilitation' (a slow build-up of response to targets that move on long, continuous trajectories) and 'selective attention', a competitive mechanism that selects one target from alternatives. Here, we present an elaborated STMD-inspired model, implemented in a closed loop target-tracking system that uses an active saccadic gaze fixation strategy inspired by insect pursuit. We test this system against heavily cluttered natural scenes. Inclusion of facilitation not only substantially improves success for even short-duration pursuits, but it also enhances the ability to 'attend' to one target in the presence of distracters. Our model predicts optimal facilitation parameters that are static in space and dynamic in time, changing with respect to the amount of background clutter and the intended purpose of the pursuit. Our results provide insights into insect neurophysiology and show the potential of this algorithm for implementation in artificial visual systems and robotic applications.

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“…2, there are also local wide-field motion detectors concurrently gathering directional information passed in both polarity channels, wherein signals merge both linearly and multiplicatively as proposed in [8]. These combinations of term coefficients θ 1 , θ 2 , θ 3 allow us to adjust different balances of contributions between separated ON and OFF channels.…”

Section: Medulla and Lobula Layersmentioning

confidence: 99%

Modeling direction selective visual neural network with ON and OFF pathways for extracting motion cues from cluttered background

Yue

2017

2017 International Joint Conference on Neural Networks (IJCNN)

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Abstract-The nature endows animals robust vision systems for extracting and recognizing different motion cues, detecting predators, chasing preys/mates in dynamic and cluttered environments. Direction selective neurons (DSNs), with preference to certain orientation visual stimulus, have been found in both vertebrates and invertebrates for decades. In this paper, with respect to recent biological research progress in motion-detecting circuitry, we propose a novel way to model DSNs for recognizing movements on four cardinal directions. It is based on an architecture of ON and OFF visual pathways underlies a theory of splitting motion signals into parallel channels, encoding brightness increments and decrements separately. To enhance the edge selectivity and speed response to moving objects, we put forth a bio-plausible spatial-temporal network structure with multiple connections of same polarity ON/OFF cells. Each pair-wised combination is filtered with dynamic delay depending on sampling distance. The proposed vision system was challenged against image streams from both synthetic and cluttered real physical scenarios. The results demonstrated three major contributions: first, the neural network fulfilled the characteristics of a postulated physiological map of conveying visual information through different neuropile layers; second, the DSNs model can extract useful directional motion cues from cluttered background robustly and timely, which hits at potential of quick implementation in visionbased micro mobile robots; moreover, it also represents better speed response compared to a state-of-the-art elementary motion detector.

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Correlation between OFF and ON Channels Underlies Dark Target Selectivity in an Insect Visual System

Cited by 53 publications

References 41 publications

Object-Detecting Neurons in Drosophila

Object-Detecting Neurons in Drosophila

Properties of neuronal facilitation that improve target tracking in natural pursuit simulations

Modeling direction selective visual neural network with ON and OFF pathways for extracting motion cues from cluttered background

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