Sensory processing

A large part of mammalian brains is dedicated to sensory processing. Sensory receptors extract distinct but partly correlated features of the environment that vary at different timescales, and then transmit them through subcortical structures and a succession of recurrently connected cortical areas. A general theory on how sensory pathways encode, propagate, and transform sensory features is still missing. To understand how biophysically realistic neural networks support these fundamental brain functions, we developed an analytical framework based on the principle of efficient coding (Barlow,

Animals rely on sensory inputs to navigate complex, dynamic environments. Understanding how the brain integrates these inputs to guide behavior remains a central question in neuroscience. Training AI and animals on the same task offers a unique opportunity to uncover both similarities and critical differences in the strategies used by biological and artificial systems. By pinpointing what the brain accomplishes that modern AI lacks, we can drive advancements in machine learning, pushing AI to more robust, generalizable solutions. In this study, we train mice and reinforcement learning agents o

…architectures contribute to multimodal sensory processing?

…operates in order to guide prioritized sensory processing. These attentional units fit neatly to accommodate our understanding of how attention is allocated in a top-down, bottom-up, or historical fashion. In this talk, I will focus on attentional phenomena that are not easily accommodated within current theories of attentional selection – the “attentional platypuses,” as they allude to an observation that within biological taxonomies the platy

…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

Predicting the location of expected upcoming stimuli is a key function in sensory processing. Noise in the environment reduces the reliability of sensory input and increases the importance of prior information. Yet, sudden changes in the environment can render this prior information irrelevant. In such cases, observers should reset their beliefs and establish new priors using current sensory evidence. To study these dynamics of perceptual belief updating, we conducted a human EEG experiment (N = 29) investigating auditory spatial localization in noisy volatile environments and analyzed the ass

…estradiol) alter sensory processing and cortical function is largely unexplored, as most research focuses on impacts within the hypothalamus and limbic system. Therefore, mechanistic insight is needed to understand the fundamental organization of sex hormone action on cortical

…to predict and prepare for future (sensory) events. Bayesian predictive processing posits that these expectations play a major role in sensory processing, perception being the result of their integration with sensory evidence in this framework. Placebo hypoalgesia (when expectations of pain relief are sufficient to relieve pain) is probably the best example of expectations biassing perception. In this experiment, we manipulated pain expectations using a classic probabilistic reversal learning task (2 visual cues assoc

A central question in neuroscience is understanding how sensory information is transformed into a motor output. To address this question, we need to know the neural circuits underlying these transformations from the sensory to the motor side, and the neuromuscular activity patterns involved. The compact nervous system of the Drosophila larva allows studying complete sensorimotor circuits. Our past research characterized neuronal circuits underlying the competition between defensive actions: startle actions e.g., Hunch and escape actions e.g. Bend, at the early stages of sensory processing (Jov

…how motivational states influence sensory processing and perceptual decision-making. In a two-whisker discrimination task performed by water-restricted mice, we observed that thirst-induced motivation significantly impacts task performance and modulates cortical sensory representations in the somatosensory

…loops of L6b neurons might enable sensory processing to extract salien

Predicting the timing of external stimuli is a key function in sensory processing. In noisy environments, the importance of prior information increases due to reduced reliability of sensory information. At the same time, sudden changes in the environment often render prior information invalid. In such cases, observers should update beliefs and establish new priors using current sensory evidence. To study these dynamic processes, our current EEG experiment investigates the behavioral and neural patterns associated with auditory temporal discrimination in a noisy and dynamically changing environ

…prediction errors and optimize sensory processing. However, the neural mechanisms that link the encoding of prediction errors and optimization of sensory representations remain unclear. Here, we provide direct evidence of how predictive learning shapes the representational geometry of the human brain. We recorded magnetoencephalography (MEG) in human participants listening to acoustic sequences with different levels of regularity. Representational similarity analysis revealed how,

…they have been shown to be involved in sensory processing, mediated by different input pathways. How dopa

…GABAergic INs has been shown to impair sensory processing and learning, emerging from adolescence on. Thus, investigating the functional maturation and network integration of VIP-INs is important for understanding brain development. Here, we studied developmental changes in passive and active membrane parameters of VIP-INs and their network integration into the developing neocortex with an emphasised focus on the maturation of their

…with impairments in both basic sensory processing and higher cognitive functions. One of the most robust findings is that Schizophrenia patients have deficient sensory processing and impairment can be captured by the reduced “mismatch negativity” (MMN), which is an event-related potential that occurs when a sequence of repetitive stimuli is interrupted by occasional oddball stimuli. Although MMN is the biomarker of Schizophrenia and robustly translational across species, the underlying mechanisms of MMN are not clear. To

…knowledge about the role of this sensory channel in the Central Nervous System. Here, we investigated the function of cortical TRPV1 in sensory processing and detection. We implemented a whisker-based vibration detection task to explore the impact of TRPV1 on sensory perception, usin

…cortical activity in the sensory areas is thought to function as corollary discharge and to modulate sensory processing during self-generated motor activity. However, the exact role, neuronal circuits, and cortical computations associated with the cortex-wide motor signals are not fully elucidated. Here, we investigated the active neuronal properties during spontaneous movement episodes in the primary somatosensory (S1) and the primary motor (M1) cortices of awake mice. Whole-cell patch-c

…across brain regions involved in sensory processing, using fMRI. By measuring changes in brain activity patterns across these regions, our approach accommodates the

…aware of a stimulus during early sensory processing or only later when information is shared in a wide-spread fronto-parietal network? Neural correlates of consciousness are typically identified by comparing brain activity when a constant stimulus (e.g., a face) is perceived versus not perceived. However, in most previous experiments, conscious perception was systematically confounded with post-perceptual processes such as decision-making and report. In thi

…is vital to human perception, multisensory integration and action planning. For example, this allows us to follow and interact with the precise timing of speech and sports. Here we investigate how visual event timing is represented and transformed across the brain’s hierarchy: from sensory processing areas, through multisensory integration areas, to frontal action planning areas. We hypothesized that the dynamics of neural responses to sensory events in sensory processing areas allows derivation of event timing representati

…In cortex, sensory processing is based on a combination of feedforward information arriving from sensory organs, and feedback information that originates in higher-order areas. Whereas feedforward information drives the activity in cortex, feedback information is thought to provide contextual signal

Hierarchical predictive coding (hPC) is one of the major theories of sensory processing and cortical computation. It provides a comprehensive explanation of the role of top-down connections in cortex, by proposing how they can guide sensory processing, and has inspired many experimental studies, ranging from electrophysiological studies of individual neurons to high-level studies of cognitive computation. Still, after twenty years of research, important questions remain open: Experimental evidence for error units, which are central to the theory, is inconclusive, and little theoretical work ex

Neuromodulators adjust sensory processing and synapses are key control sites for such plasticity. Less clear is how neuromodulation alters the amount of information that synapses transmit through a circuit. To understand the operation of the “vesicle code” the experimenter needs to isolate signals from individual active zones with a resolution of single vesicles while observing or controlling the incoming signal. This has not been possible using electrophysiology but can now be achieved by multiphoton imaging of the glutamate reporter iGluSnFR in the retina of larval zebrafish. This approach