Biology subjects

Symonova, O.

Publications and source records attributed to Symonova, O..

4 recordsLinked to original sources

bioRxiv2023

A thalamic hub of action cues coordinates early visual processing and perception

Distinguishing between sensory experiences elicited by external stimuli and an animals own actions is critical for accurate perception and motor control. However, the diversity of behaviors and their complex influences on the senses make this distinction challenging. Here, we uncover an action cue hub that coordinates both visual processing in the brains first visual relay and motor commands. We show that the ventral lateral geniculate nucleus (vLGN) acts as a corollary discharge (CD) center, integrating visual translational optic flow signals and motor copies from saccades, locomotion, and pupil dynamics. The vLGN relays these signals to correct action-specific visual distortions and refine perception, as shown for the superior colliculus and a depth estimation task. Simultaneously, brain-wide vLGN projections drive corrective actions necessary for accurate visuomotor control. Our results reveal an extended CD architecture that refines early visual transformations and coordinates actions via a distributed hub-and-spoke network enabling visual perception during action.

neuroscience↗

bioRxiv2023

Gap junctions arbitrate binocular course control in flies

Animals utilize visual motion cues to maintain stability and navigate accurately. The optomotor response, a reflexive behavior for visual stabilization, has been used to study this visuomotor transformation. However, there is a disparity between the simplicity of this behavior and the intricate circuit components believed to govern it. Here we bridge this divide by exploring the course control repertoire in Drosophila and establishing a direct link between behavior and the underlying circuit motifs. Specifically, we demonstrate that visual motion information from both eyes plays a crucial role in movement control through bilateral interactions facilitated by gap junctions. These electrical interactions augment the classic stabilization behavior by inverting the response direction and the behavioral strategy. Our findings reveal how animals combine monocular motion cues to generate a variety of behaviors, determine the functional role of the circuit components, and show that gap junctions can mediate non-linear operations with a decisive role in animal behavior.

neuroscience↗

bioRxiv2022

Subcortical circuit dysfunctions delay perceptual decision-making in autism models

Despite the diverse genetic origins of autism spectrum disorders (ASDs), affected individuals share strikingly similar and correlated behavioural traits that include perceptual and sensory processing challenges. Notably, the severity of these sensory symptoms is often predictive of the expression of other autistic traits. However, the origin of these perceptual deficits remains largely elusive. Here, we show a recurrent impairment in visual threat perception that is similarly impaired in three independent models of ASD with different molecular aetiologies. Interestingly, this deficit is associated with reduced avoidance of threatening environments - a non-perceptual trait. Focusing on a common cause of ASDs, the Setd5 gene mutation, we define the molecular mechanism. We show that the perceptual impairment is caused by a potassium channel (Kv1) mediated hypoexcitability in a subcortical node essential for the initiation of escape responses, the dorsal periaqueductal grey (dPAG). Targeted pharmacological Kv1 blockade rescued both perceptual and place avoidance deficits, causally linking seemingly unrelated trait deficits to the dPAG. Our findings reveal a link between rapid perception controlled by subcortical pathways and appropriate learned interactions with the environment, and define a non-developmental source of such deficits in ASD.

neuroscience↗

bioRxiv2022

Panoramic visual statistics shape retina-wide organization of receptive fields

Statistics of natural scenes are not uniform - their structure varies dramatically from ground to sky. It remains unknown whether these non-uniformities are reflected in the large-scale organization of the early visual system and what benefits such adaptations would confer. Here, by relying on the efficient coding hypothesis, we predict that changes in the structure of receptive fields across visual space increase the efficiency of sensory coding. We show experimentally that, in agreement with our predictions, receptive fields of retinal ganglion cells change their shape along the dorsoventral retinal axis, with a marked surround asymmetry at the visual horizon. Our work demonstrates that, according to principles of efficient coding, the panoramic structure of natural scenes is exploited by the retina across space and cell-types.

neuroscience↗