Biology subjects

Solyga, M.

Publications and source records attributed to Solyga, M..

4 recordsLinked to original sources

bioRxiv2025

Visuomotor mismatch EEG responses in occipital cortex of freely moving human subjects

Likely the strongest predictor of visual feedback is self-motion. In mice, the coupling between movement and visual feedback is learned with first visual experience of the world (Attinger et al., 2017), and brief perturbations of the coupling result in strong visuomotor mismatch responses in visual cortex that possibly reflect prediction errors (Keller et al., 2012; Zmarz and Keller, 2016). In humans, predictive coding has primarily been studied using oddball paradigms which rely on violations of stimulus probability based on recent sensory history. It was still unclear, however, whether humans exhibit visuomotor mismatch responses similar to those observed in mice. This question was important for two reasons. First, visuomotor mismatch responses in humans constitute a basis to start translating the mechanistic understanding of the circuit that computes these responses from mouse to human cortex. Second, a paradigm that can trigger strong prediction error responses and consequently requires shorter recording times would simplify experiments in a clinical setting. Here, by combining a wireless EEG recording system with a virtual reality headset, we found robust visuomotor mismatch responses in human cortex that were characterized by a reversed polarity relative to visual evoked responses and a greater signal power than both visual responses and oddball mismatch responses.

neuroscience↗

bioRxiv2023

Multimodal mismatch responses in mouse auditory cortex

Our movements result in predictable sensory feedback that is often multimodal. Based on deviations between predictions and actual sensory input, primary sensory areas of cortex have been shown to compute sensorimotor prediction errors. How prediction errors in one sensory modality influence the computation of prediction errors in another modality is still unclear. To investigate multimodal prediction errors in mouse auditory cortex (ACx), we used a virtual environment to experimentally couple running to both self-generated auditory and visual feedback. Using two-photon microscopy, we first characterized responses of layer 2/3 (L2/3) neurons to sounds, visual stimuli, and running onsets and found responses to all three stimuli. Probing responses evoked by audiomotor mismatches, we found that they closely resemble visuomotor mismatch responses in visual cortex (V1). Finally, testing for cross modal influence on audiomotor mismatch responses by coupling both sound amplitude and visual flow speed to the speed of running, we found that audiomotor mismatch responses were amplified when paired with concurrent visuomotor mismatches. Our results demonstrate that multimodal and non-hierarchical interactions shape prediction error responses in cortical L2/3.

neuroscience↗

bioRxiv2021

DAF-2/insulin IGF-1 receptor regulates mobility during ageing by integrating opposite inputs from muscle and neuronal tissues

During ageing, preservation of locomotion is generally considered an indicator of sustained good health, in elderlies and in animal models. In C. elegans, mutants of the insulin-IGF-1 receptor DAF-2/IIRc represent a paradigm of healthy ageing, as their increased lifespan is accompanied by a delay in age-related loss of motility. However, these animals are less mobile than wild-type animals in early adulthood. Here we investigated the DAF-2/IIRc- dependent relationship between longevity and motility using an auxin-inducible degron to trigger tissue-specific degradation of endogenous DAF-2/IIRc. As previously reported, inactivation of DAF-2/IIRc in neurons or intestine was sufficient to extend the lifespan of worms, whereas depletion in epidermis, germline or muscle was not. However, neither intestinal nor neuronal depletion of DAF-2/IIRc prevented the age-related loss of motility. In 1-day-old adults, DAF-2/IIRc depletion in neurons reduced motility in a DAF-16/FOXO dependent manner, while muscle depletion had no effect. By contrast, DAF-2 depletion in the muscle of middleage animals improved their motility independently of DAF-16/FOXO but required UNC-120/SRF. Yet, neuronal or muscle DAF-2/IIRc depletion both preserved the mitochondria network in ageing muscle. Overall, these results show that the motility pattern of daf-2 mutants is determined by the sequential and opposing impact of neurons and muscle tissues and can be dissociated from the regulation of the lifespan. This work also provides the characterization of a versatile tool to analyze the tissue-specific contribution of insulin-like signaling in integrated phenotypes at the whole organism level.

physiology↗

bioRxiv2021

Emergence and function of cortical offset responses in sound termination detection

Offset responses in auditory processing appear after a sound terminates. They arise in neuronal circuits within the peripheral auditory system, but their role in the central auditory system remains unknown. Here we ask what the behavioural relevance of cortical offset responses is and what circuit mechanisms drive them. At the perceptual level, our results reveal that experimentally minimizing auditory cortical offset responses decreases the mouse performance to detect sound termination, assigning a behavioural role to offset responses. By combining in vivo electrophysiology in the auditory cortex and thalamus of awake mice, we also demonstrate that cortical offset responses are not only inherited from the periphery but also amplified and generated de novo. Finally, we show that offset responses code more than silence, including relevant changes in sound trajectories. Together, our results reveal the importance of cortical offset responses in encoding sound termination and detecting changes within temporally discontinuous sounds crucial for speech and vocalization.

neuroscience↗