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Cianfarano, E.

Publications and source records attributed to Cianfarano, E..

4 recordsLinked to original sources

RetINaBox: A hands-on learning tool for experimental neuroscience

An exciting aspect of neuroscience is developing and testing hypotheses via experimentation. However, due to logistical and financial hurdles, the experiment and discovery component of neuroscience is generally lacking in classroom and outreach settings. To address this issue, here we introduce RetINaBox: a low-cost open-source electronic visual system simulator that provides users with a hands-on tool to discover how the visual system builds feature detectors. RetINaBox features an LED array for generating visual stimuli and a photodiode array that acts as a mosaic of model photoreceptors. Custom software on a Raspberry Pi computer reads out responses from model photoreceptors and allows users to control the polarity and delay of the signal transfer from model photoreceptors to model retinal ganglion cells. Interactive lesson plans are provided, guiding users to discover different types of visual feature detectors--including ON/OFF, center-surround, orientation selective, and direction selective receptive fields--as well as their underlying circuit computations.

neuroscience↗

Norepinephrine acts through radial astrocytes in the developing optic tectum to enhance threat detection and escape behavior

The ability to switch behavioral states is essential for animals to adapt and survive. We investigated how norepinephrine (NE) activation of radial astrocytes alters visual processing in the optic tectum (OT) of developing Xenopus laevis. NE activates calcium transients in radial astrocytes through 1-adrenergic receptors. NE and radial astrocyte activation shifted OT response selectivity to preferentially respond to looming stimuli, associated with predation threat. NE-mediated astrocytic release of ATP/adenosine reduced excitatory transmission by retinal ganglion cell axons, without affecting inhibitory transmission in the OT. Blockade of adenosine receptors prevented both decreased neurotransmission and the selectivity shift. Chemogenetic activation of tectal radial astrocytes reproduced NEs effects and enhanced behavioral detection of looming stimuli in freely swimming animals. NE signaling via radial astrocytes enhances network signal-to-noise for detecting threatening stimuli, with important implications for sensory processing and behavior.

neuroscience↗

The feature landscape of visual cortex

Understanding computations in the visual system requires a characterization of the distinct feature preferences of neurons in different visual cortical areas. However, we know little about how feature preferences of neurons within a given area relate to that areas role within the global organization of visual cortex. To address this, we recorded from thousands of neurons across six visual cortical areas in mouse and leveraged generative AI methods combined with closed-loop neuronal recordings to identify each neurons visual feature preference. First, we discovered that the mouses visual system is globally organized to encode features in a manner invariant to the types of image transformations induced by self-motion. Second, we found differences in the visual feature preferences of each area and that these differences generalized across animals. Finally, we observed that a given areas collection of preferred stimuli ( own-stimuli) drive neurons from the same area more effectively through their dynamic range compared to preferred stimuli from other areas ( other-stimuli). As a result, feature preferences of neurons within an area are organized to maximally encode differences among own-stimuli while remaining insensitive to differences among other-stimuli. These results reveal how visual areas work together to efficiently encode information about the external world.

neuroscience↗

Identifying representational structure in CA1 to benchmark theoretical models of cognitive mapping

Decades of theoretical and empirical work have suggested the hippocampus instantiates some form of a cognitive map. Yet, tests of competing theories have been limited in scope and largely qualitative in nature. Here, we develop a novel framework to benchmark model predictions against observed neuronal population dynamics as animals navigate a series of geometrically distinct environments. In this task space, we show a representational structure in the dynamics of hippocampal remapping that generalizes across brains, discriminates between competing theoretical models, and effectively constrains biologically viable model parameters. With this approach, we find that accurate models capture the correspondence in spatial coding of a changing environment. The present dataset and framework thus serve to empirically evaluate and advance theories of cognitive mapping in the brain. HIGHLIGHTSO_LIWe identify representational structure in CA1 remapping that is reliable across brains. C_LIO_LIWe directly compare models of cognitive mapping to this representation in CA1. C_LIO_LIModels based on local boundary distance and direction predict CA1 representation. C_LIO_LIThis approach reveals a biologically viable parameter space for model predictions. C_LIO_LIAccurate models capture the correspondence of spatial codes across environments. C_LI

neuroscience↗