Sensory neurons

…is encoded in the spiking activity of neurons. Consequently, little is known about how sensory neurons can preserve information from multiple stimuli – a problem given that many sensory neurons have relatively broad receptive fields. Multiplexing is a neural encoding theory that posits that neurons temporally switch between encoding various stimuli when more than one stimulus is present. To date, the strongest statistical evidence for this theory comes from spike counts measured over long time windows, leading

How the activity of sensory neurons supports perceptual decisions remains one of the central questions of systems neuroscience. Two primary frameworks guide the field’s thinking on this question. One framework, guided by ideas of information maximization, redundancy reduction, and efficient coding, focuses on the decision-related information represented by neural responses and how it is extracted from sensory populations. In another framework, based on the Bayesian brain hypothesis, sensory responses represent posterior beliefs about the outside world, which then guide decision-making. Interes

A major challenge in sensory systems is to understand how neurons extract information from the natural environment. Models derived from their responses to artificial stimuli often have a hard time to generalize and predict responses to natural scenes. However, models directly learned on the responses to natural scenes can be hard to interpret. To address this issue, we have recently developed an approach where we add small perturbations to natural scenes and measure how these perturbations change neuronal responses, to better understand the features extracted by sensory neurons. I will show se

…modulatory effects of movement on sensory coding. Surprisingly, these effects are not consistent across species. For example, in rodents and insects locomotion increases the magnitude of visual responses [1-3], while in primates, locomotion has a weak suppressive influence [4]. These differences raise intriguing questions about the computational purpose of such modulations and the generality of the underlying principles of sensory processing. Here, we address these questions from a theoretical perspective. Our approach is groun

Activity of sensory neurons is driven not only by stimuli but also by the behavior of the animal. For example, in the primary visual cortex (V1) of a mouse, the gain of sensory responses is modulated by the speed of movement [1]. On average, the response strength increases with running speed - this effect is prominent and systematic. Individual neurons can, however, reveal distinctive patterns of gain modulation. This diversity raises questions about how nuanced the impact of behavior on sensory coding is, whether it is limited to coarse gain changes, and what its computational function might

…More concretely, neurons in the Middle Temporal area (MT) respond heterogeneously and nonlinearly to stimuli inside their receptive fields (RFs) [1-3], and these neurophysiological properties could mediate spatial suppression of motion obs

Aims: Metabolic profile impacts on tissue development including neurons in brain, yet the full repertoire of metabolic signals that shape developing neuronal architecture remain mysterious. Our aim is to clarify the metabolic crosstalk that coordinates the early acquisition of the neurite complexity in developing neurons. Methods: To investigate the factors involved in metabolic switch, we used transcriptomics analysis on the sensory neurons cultured in different metabolic demand. IPA analysis was used to interpret the transcriptomics data. We applied MEME-ChIP method on comprehensive motif an

2- 3% of population are affected by neurodevelopmental disorders (NDDs), causing severe intellectual impairment, health complications and reduced life expectancy. In approximately half of the affected individuals the causal genetic variants remain unknown. Utilizing a comprehensive genetic screening strategy in a cohort of consanguineous families with multiple affected children, several gene variants associated with NDDs were identified. Among these, KCNH5 emerged as a compelling candidate due to its high expression in the nervous system and high degree of conservation in Drosophila melanogast

Cell culture is a fundamental experimental tool for understanding cell physiology. However, translating these findings to in vivo settings has proven challenging. Replicating donor tissue conditions, including oxygen levels, is crucial for achieving meaningful results. Nevertheless, oxygen culture conditions are often overlooked, particularly in the context of chemotherapy-induced neurotoxicity. In this study we want to investigate the role of oxygen levels in primary neuronal cultures by comparing neuron performance under cisplatin exposure (1 µg/ml) in normoxia (representing atmospheric cond

…cell type that ensheath the body of sensory neurons in the peripheral nervous system and in health SGCs are believed to contribute to neuronal homeostasis. However, evidence suggests that in certain disease states such as a traumatic nerve injury, satellite glial cells contribute to the development of chronic pain. Recent advances in single-cell RNA sequencing (scRNAseq) have prompted the

Our ability to feel a touch relies on the activity of sensory neurons located within the skin. These neurons are able to detect nanometer-scale mechanical displacements at the skin surface and to transduce them into electrical signals. All mechanotransduction complexes identified so far rely on tethering mechanisms. We hypothesize that, similarly, mechanotransduction in the skin requires coupling between the mechanosensitive ion channels and the extracellular matrix mediated by protein tethers. In sensory neurons cultured on a laminin matrix and imaged either with TEM or FIB/SEM, these tethers

…described Tusc5 in projection sensory neurons. Glut4 transporters (localized in muscles and adipocytes) are continuously recycled through endosomes from and to the plasma membrane and stored in GSVs (Glut4 Storage Vesicles). In adipocites, Tusc5 follows Glut4 trafficking between GSVs and cell surface, upon insulin stimulation. Tusc5 interacts with the signaling cascade of fusion of GSVs with the plasma membrane, similar to the exocytosis mechanism in neuronal

…culture of human iPSC-derived neurons, then predict drug-induced neurotoxicity by morphological analysis.COP (Cyclo olefin polymer), which has excellent observability and low drug adsorption, is used as the material of the MPS. Successful culture of human iPSC-derived sensory neurons and human iPSC-derived cortical neurons with sepa

microRNAs (miRNAs) are small non-coding RNAs (ncRNAs) of ~22 nucleotides that regulate gene expression in all biological processes in health and disease, including nerve injury-induced neuronal regeneration and neuropathic pain. Although miRNAs have been under investigation for their potential application as biomarkers or even in novel therapeutic approaches, the signaling pathways involved in their regulation as well as their biological role remains elusive. Mice were subjected to the spared nerve injury model for neuropathic pain and paired-miRNA::mRNA sequencing was performed on dorsal root

…systems, including the internal mechanosensory organs. However, the progress has been slow due to technical hurdles: the sensory neurons are deeply buried inside the body and are not readily accessible for direct observation, the projection patterns from different organs or body parts are complex rather than converging into dedicate brain regions, the coding principle cannot be directly adapted from that learned from conventiona

Sensory neurons in many organisms and brain areas exhibit a form of local gain control that has been described as "divisive normalization'' (Carandini & Heeger, 2011) in which the stimulus-driven activity of each neuron is divided by a factor involving the summed activity of a group of neurons. Redundancy reduction has been proposed as normative explanation of divisive normalization, and previous work has used this principle for learning normalization models (Schwartz & Simoncelli, 2000). Specifically, redundancy in filtered representations of images can be reduced by dividing by an es

The efficient coding theory postulates that sensory neurons compress relevant information before sending it to the rest of the brain. To this end, these neurons are thought not to signal all input features, but only surprising events, e.g. mismatches between expected and perceived inputs. In the retina, it has been shown that ganglion cells, the retinal output, strongly respond when a periodic sequence of flashes suddenly ends. Strikingly, the latency of this response shifts by the same amount as the period of the flash sequence, as if ganglion cells responded to the omitted flash with constan

…thought to be detected by primary sensory neurons and then distinguished by downstream brain circuits. Sensory adaptation is a neural mechanism that filters background by minimizing responses to stable sensory stimuli, and a fundamental feature of sensory systems. Adaptation over relatively fast timescales (milliseconds to minutes) have been reported in many sensory systems. However, adaptation to persistent environmental stimuli over longer timescales (hours to days) have bee

The response of sensory neurons to different stimuli are largely characterized by tuning curves, with a peak of activity at a preferred stimulus. Tuning curves are thought to be shaped by Hebbian plasticity during development through the strengthening of synapses between neurons with similar functional preferences. This raises the hypothesis that the strength of synapses should correlate with the difference in functional preference between pre- and postsynaptic activity. A recent study, however, found that the functional preference of cortical neurons was correlated with the number of spines a

Understanding how sensory neurons extract relevant information from natural scenes is a major challenge in neuroscience. Probing sensory systems with simple stimuli give limited insights on natural scene processing, and probing selectivity during natural scene stimulation is difficult. Even in the retina, is not clear how Retinal ganglion cells (RGC) extract specific features from natural scenes and send this information to the brain. Many studies using simple, artificial stimuli have shown responses to local light increase (ON-responses), and/or decrease (OFF), but it is unclear if this selec

Sensory neurons in different species, brain areas, and modalities adjust their sensitivity (gain) in response to recent stimulus history. This gain control offers a mechanism for single neurons to rapidly and reversibly adapt to different stimulus contexts while preserving synaptic weights that serve to represent features that remain consistent across contexts. From a normative perspective, this allows an individual neuron to adjust the dynamic range of its responses to accommodate changes in input statistics -- a core tenet of Barlow's efficient coding theory. However, experimental measureme

Sensory neurons can integrate their inputs nonlinearly, and this nonlinear pooling allows the extraction of complex features from the natural environment. Such nonlinear computations are ubiquitous in the visual system, and can be captured with encoding models that partition receptive fields into subunits whose outputs are nonlinearly combined. In the retina, the nonlinearities that transform subunit signals before integration by retinal ganglion cells affect the cells’ sensitivity to the spatial structure of natural scenes. Fitting subunit models to neural responses remains a challenge, as av

Brains must integrate complex sensory information and compare to past events to generate appropriate behavioral responses. The neural circuit basis of these computations is unclear and the underlying structure unknown. Here, we mapped the comprehensive synaptic wiring diagram of the fruit fly larva brain, which contains 3,013 neurons and 544K synaptic sites. It is the most complete insect connectome to date: 1) Both brain hemispheres are reconstructed, allowing investigation of neural pathways that include contralateral axons, which we found in 37% of brain neurons. 2) All sensory neurons and

Local anesthetics decrease the excitability of all neurons by blocking voltage-gated sodium channels non-selectively. We have developed a technology to silence only those sensory neurons – the nociceptors – that trigger pain, itch, and cough. I will tell you why and how we devised the strategy, the way we showed that it works, and will also discuss its implications for treating multiple human disorders.