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Nourizonoz, A.

Publications and source records attributed to Nourizonoz, A..

3 recordsLinked to original sources

BlueBerry: Closed-loop wireless optogenetic manipulation in freely moving animals

Optogenetics is a powerful approach for linking neural activity to behavior by enabling precise manipulation of defined neuronal populations. Recent advances in wireless technologies have led to remotely controlled optogenetic devices that facilitate the study of more complex behaviors, including social interactions. However, implementing real-time, automated, closed-loop experiments in large-scale, naturalistic environments and in groups of interacting animals remains challenging. Moreover, many existing devices are difficult to reproduce, requiring specialized engineering expertise or fabrication facilities that are not widely available. Here we introduce BlueBerry (www.OptoBlueBerry.org), a lightweight (1.4 g), battery powered, multi-channel wireless optogenetic device that is openly available for the scientific community and can be assembled entirely from off-the-shelf-components. BlueBerry combines robust long-range wireless communication with flexible control of stimulation parameters, making it particularly suited for behavior-triggered optogenetic experiments in large arenas and in multiple freely interacting animals. We demonstrate that BlueBerry can not only guide decision making during large-scale navigation, but also deliver individually controlled, behavior-triggered optogenetic stimulation to multiple freely interacting mice, enabling modulation of social dynamics in real-time. The open availability, modular design, and straightforward integration with existing behavioral frameworks make BlueBerry a practical and scalable tool for systems neuroscience.

neuroscience↗

Lamellar Schwann cells in the Pacinian corpuscle potentiate vibration perception

Pacinian corpuscles are among the most sensitive mechanoreceptors found in vertebrates and they are tuned to vibrations in the highest perceptible frequency range (100-2000Hz). One of their anatomical hallmarks is the onion-like cell layers surrounding the central axon. The innermost layers consist of [~]60 densely packed lamellar Schwann cells (LSCs), whose function remains largely unknown. Using high-resolution 3D electron microscopy we found that LSCs in Pacinian corpuscles of the mouse hindlimb do not form concentric rings, but complex, multilayered and intertwining assemblies that are connected via an estimated 5805.1 desmosomes and 4142.5 gap-junctions. LSCs make multiple converging contacts with the afferent axon and its protrusions with desmosomes. Using optogenetic manipulations of LSCs we demonstrate that their activation does not only drive reliable time-locked spiking in the axon, but that their inactivation significantly elevates the thresholds in-situ and increases perceptual thresholds behaviorally. Together these findings provide evidence that LSCs are a key element of somatosensory processing, actively potentiating mechanosensitivity in Pacinian corpuscles. HighlightsO_LIHigh-resolution electron microscopy reveals details of the Pacinian corpuscle C_LIO_LILamellar Schwann cells form claw-like structures with converging axonal contacts C_LIO_LISchwann-cell modulation bidirectionally affects neural coding of Pacinian afferent C_LIO_LIInactivation of lamellar Schwann-cells increases perceptual thresholds C_LI

neuroscience↗

Common computational principle for vibro-tactile pitch perception in mouse and human

We live surrounded by vibrations generated by moving objects. These oscillatory stimuli can produce sound (i.e. airborne waves) and propagate through solid substrates. Pitch is the main perceptual characteristic of sound, and a similar perceptual attribute seems to exist in the case of substrate vibrations: vibro-tactile pitch. Here, we establish a mechanistic relationship between vibro-tactile pitch perception and the actual physical properties of vibrations using behavioral tasks, in which vibratory stimuli were delivered to the human fingertip or the mouse forelimb. The resulting perceptual reports were analyzed with a model demonstrating that physically different combinations of vibration frequencies and amplitudes can produce equal pitch perception. We found that the perceptually indistinguishable but physically different stimuli follow a common computational principle in mouse and human. It dictates that vibro-tactile pitch perception is shifted with increases in amplitude toward the frequency of highest vibrotactile sensitivity. These findings suggest the existence of a fundamental relationship between the seemingly unrelated concepts of spectral sensitivity and pitch perception.

neuroscience↗