Spatio-temporal relays control layer identity of direction-selective neuron subtypes in Drosophila

Visual motion detection in sighted animals is essential to guide behavioral actions ensuring their survival. In Drosophila, motion direction is first detected by T4/T5 neurons. Their axons innervate one of four lobula plate layers. How T4/T5 neurons with layer-specific representation of motion-direction preferences are specified during development is unknown. We show that diffusible Wingless (Wg) between adjacent neuroepithelia induces its own expression to form secondary signaling centers. These activate Decapentaplegic (Dpp) signaling in adjacent lateral tertiary neuroepithelial domains dedicated to producing layer 3/4-specific T4/T5 neurons. T4/T5 neurons derived from the core domain devoid of Dpp signaling adopt the default layer 1/2 fate. Dpp signaling induces the expression of the T-box transcription factor Optomotor-blind (Omb), serving as a relay to postmitotic neurons. Omb-mediated repression of Dachshund transforms layer 1/2-into layer 3/4-specific neurons. Hence, spatio-temporal relay mechanisms, bridging the distances between neuroepithelial domains and their postmitotic progeny, implement T4/T5 neuron-subtype identity.

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Visual Motion-Detection Circuits in Flies: Parallel Direction- and Non-Direction-Sensitive Pathways between the Medulla and Lobula Plate

Journal of Neuroscience ◽

10.1523/jneurosci.16-15-04551.1996 ◽

1996 ◽

Vol 16 (15) ◽

pp. 4551-4562 ◽

Cited By ~ 69

Author(s):

John K. Douglass ◽

Nicholas J. Strausfeld

Keyword(s):

Motion Detection ◽

Visual Motion ◽

Lobula Plate ◽

Parallel Direction ◽

Visual Motion Detection

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Bayesian Computation in Recurrent Neural Circuits

Neural Computation ◽

10.1162/08997660460733976 ◽

2004 ◽

Vol 16 (1) ◽

pp. 1-38 ◽

Cited By ~ 138

Author(s):

Rajesh P. N. Rao

Keyword(s):

Motion Detection ◽

Network Architecture ◽

Discrimination Task ◽

Visual Motion ◽

Natural World ◽

Direction Selectivity ◽

Orientation Discrimination ◽

Posterior Probabilities ◽

Motion Direction ◽

Model Network

A large number of human psychophysical results have been successfully explained in recent years using Bayesian models. However, the neural implementation of such models remains largely unclear. In this article, we show that a network architecture commonly used to model the cerebral cortex can implement Bayesian inference for an arbitrary hidden Markov model. We illustrate the approach using an orientation discrimination task and a visual motion detection task. In the case of orientation discrimination, we show that the model network can infer the posterior distribution over orientations and correctly estimate stimulus orientation in the presence of significant noise. In the case of motion detection, we show that the resulting model network exhibits direction selectivity and correctly computes the posterior probabilities over motion direction and position. When used to solve the well-known random dots motion discrimination task, the model generates responses that mimic the activities of evidence-accumulating neurons in cortical areas LIP and FEF. The framework we introduce posits a new interpretation of cortical activities in terms of log posterior probabilities of stimuli occurring in the natural world.

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High Mobility Group Protein 1 Interacts Specifically with the Core Domain of Human TATA Box-binding Protein and Interferes with Transcription Factor IIB within the Pre-initiation Complex

Journal of Biological Chemistry ◽

10.1074/jbc.274.3.1628 ◽

1999 ◽

Vol 274 (3) ◽

pp. 1628-1634 ◽

Cited By ~ 56

Author(s):

Montserrat Sutrias-Grau ◽

Marco E. Bianchi ◽

Jordi Bernués

Keyword(s):

Transcription Factor ◽

High Mobility ◽

Tata Box ◽

High Mobility Group Protein ◽

Initiation Complex ◽

Core Domain ◽

The Core ◽

Transcription Factor Iib ◽

Group Protein ◽

Tata Box Binding Protein

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Motion Direction Discrimination with Tactile Random-Dot Kinematograms

i-Perception ◽

10.1177/20416695211004620 ◽

2021 ◽

Vol 12 (2) ◽

pp. 204166952110046

Author(s):

Scinob Kuroki ◽

Shin’ya Nishida

Keyword(s):

Motion Detection ◽

Visual Motion ◽

Discrimination Performance ◽

Sensory Function ◽

Human Observer ◽

Motion Sensing ◽

Motion Direction ◽

Low Level ◽

Direction Discrimination ◽

High Level

Motion detection is a fundamental sensory function for multiple modalities, including touch, but the mechanisms underlying tactile motion detection are not well understood. While previous findings supported the existence of high-level feature tracking, it remains unclear whether there also exist low-level motion sensing that directly detects a local spatio-temporal correlation in the skin-stimulation pattern. To elucidate this mechanism, we presented, on braille displays, tactile random-dot kinematograms, similar to those widely used in visual motion research, which enables us to independently manipulate feature trackability and various parameters of local motion. We found that a human observer is able to detect the direction of difficult-to-track tactile motions presented to the fingers and palms. In addition, the direction-discrimination performance was better when the stimuli were presented along the fingers than when presented across the fingers. These results indicate that low-level motion sensing, in addition to high-level tracking, contribute to tactile motion perception.

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