Sensory perception

Hokto Kazama’s Laboratory for Circuit Mechanisms of Sensory Perception studies how Drosophila neural circuits process sensory information and generate behavior. The part-time researcher will support genetic crosses, experiments and analysis involving anatomy, in-vivo physiology and behavior. Employment begins 1 April 2027, negotiable. The Wako-based appointment pays JPY 1,600–2,200 per hour, with negotiable weekday hours and renewable one-year contracts. Applications are open until filled. Upload the documents through the official link and notify the laboratory as its instructions require.

…Furthermore, the potential sensory augmentation provided b

Deficits in sensory perception characterize Huntington disease (HD), alongside motor and cognitive impairments. This study investigates altered cortical network connectivity in HD, focusing on sensory spread, where sensory stimulation provokes more extensive cortical activity in HD model mice compared to wild-type (WT) controls.In vivo, we utilized widefield, mesoscale calcium imaging in the awake, head-fixed zQ175 mouse model of HD, crossed with Thy1-GCaMP mice, expressing GCaMP in cortical pyramidal neurons. In vivo, LED flashes induced visual responses imaged through an intact-skull cranial

Sensory perception allows us to receive and integrate information from the environment, a process that starts right from birth. Indeed, newborns can interact with their environment and perform sensorimotor tasks soon after birth, without any previous experience of patterned sensory input. Understanding how neurons assemble into circuits that developmentally prepare to encode visual information accordingly to arousal states is still poorly understood and is likely to provide critical insight not only into how these circuits function, but also how they malfunction in various neurological conditi

Mechanisms of top-down modulation in sensory perception and their relation to the underlying connectivity are not completely understood. Here we present a computational model of two interconnected cortical areas and use it to study the impact of inter-areal connectivity on sensory processing. The model integrates a multitude of data from rodent primary somatosensory cortex and reproduces biological features across multiple scales: from tens of ion channel models and electrical types, to thousands of morphologically detailed neurons, to millions of stochastic synapses mediating local and long-r

The integration of sensory inputs from different senses is a crucial aspect of sensory perception and behavioral decisions. Whether such multisensory integration occurs at specific stages of neural processing remains unclear. Two brain regions, the anterolateral motor cortex (ALM) and the superior colliculus (SC) are important parts of a cortico-subcortical loop that transforms multisensory inputs into behavioral decisions. To study the role of these areas in multisensory integration and decision-making, we trained mice in a multisensory discrimination task, where animals had to integrate visu

…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

A prominent theory of sensory perception advocates that perception in the brain is implemented via probabilistic inference. The neural sampling hypothesis (NSH) posits that neuronal responses to a stimulus represent samples from the posterior distribution over latent world state variables (e.g., object identity) that underlie the stimulus. Existing work on NSH commonly evaluates qualitative agreement of experimental data with simple generative models of the stimulus and does not fit NSH models to experimentally observed sensory population responses. We propose a novel formulation for NSH that

Neural activity in sensory cortex combines stimulus responses and ongoing activity, but it remains unclear whether they reflect the same underlying dynamics or separate processes. Here we show that during wakefulness, the neuronal assemblies evoked by sounds in the auditory cortex and thalamus are specific to the stimulus and distinct from the assemblies observed in ongoing activity. In contrast, during anesthesia, evoked assemblies are indistinguishable from ongoing assemblies in the cortex, while they remain distinct in the thalamus. A strong remapping of sensory responses accompanies this d

In this talk I will discuss our recent findings that sensory signals from the brain adjust the physiology and behavior of the nematode C. elegans, enabling this animal to deal with the lethal threat of hydrogen peroxide. Hydrogen peroxide (H2O2) is the most common chemical threat in the microbial battlefield. Prevention and repair of the damage that hydrogen peroxide inflicts on macromolecules are critical for health and survival. In the first part of the talk, I will discuss our findings that C. elegans represses their own H2O2 defenses in response to sensory perception of Escherichia coli, t

…and meaningful representations from sensory inputs that are often ambiguous or corrupt. Since only information that permeates the cortical hierarchy can influence sensory perception and decision-making, it is critical that noisy external stimuli are encoded and propagated through different processing stages with minimal signal degradation. Here we hypothesize that stimulus-specific pathways akin to cortical topographic maps may provide the structural scaffold for such signal routing. We investigate whether the featur

…explanations for atypical sensory perception in autism are lacking. To address this, we quantitively condensed findings from the non-social autism fMRI literature in line with the current best practices for neuroimaging meta-analyses. Using activation likelihood estimation (ALE), we conducted a series of robust meta-analyses across 83 experiments from 52 fMRI studies investigating differences between autistic (n = 891) and typical (n = 967) participants. We found that typical c

All sensory perception and every coordinated movement, as well as feelings, memories and motivation, arise from the bustling activity of many millions of interconnected cells in the brain. The ultimate function of this elaborate network is to generate behavior. We use zebrafish as our experimental model, employing a diverse array of molecular, genetic, optical, connectomic, behavioral and computational approaches. The goal of our research is to understand how neuronal circuits integrate sensory inputs and internal state and convert this information into behavioral responses.

…in key behaviors such as for example sensory perception has only recently been established. In my presentation I will discuss how computational modelling has helped us illuminate dendritic function. I will present the main findings of a number of projects in lab dealing with dendritic nonlinearities in excitatory and inhibitory and their consequences on neuronal tun

Individual neurons in visual cortex provide the brain with unreliable estimates of visual features. It is not known if the single-neuron variability is correlated across large neural populations, thus impairing the global encoding of stimuli. We recorded simultaneously from up to 50,000 neurons in mouse primary visual cortex (V1) and in higher-order visual areas and measured stimulus discrimination thresholds of 0.35 degrees and 0.37 degrees respectively in an orientation decoding task. These neural thresholds were almost 100 times smaller than the behavioral discrimination thresholds reported

…the transformation of information from sensory perception to behavioural output. Importantly, they also aim to further understand the cell-type specific processes that interrupt the flow of information through neural circuits in neurodegenerative disorders with dementia. The Pakan

Single neurons in visual cortex provide unreliable measurements of visual features due to their high trial-to-trial variability. It is not known if this “noise” extends its effects over large neural populations to impair the global encoding of stimuli. We recorded simultaneously from ∼20,000 neurons in mouse primary visual cortex (V1) and found that the neural populations had discrimination thresholds of ∼0.34° in an orientation decoding task. These thresholds were nearly 100 times smaller than those reported behaviourally in mice. The discrepancy between neural and behavioural discrimination