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Oladepo, I.

Publications and source records attributed to Oladepo, I..

4 recordsLinked to original sources

Coordinated Representational Drift Across the Mouse Cortex

Cortical neurons continuously change their spatial tuning properties over days and weeks, yet how this representational drift is coordinated across distributed cortical networks remains unknown. Using a robotic cranial exoskeleton for chronic widefield calcium imaging with cellular resolution, we tracked over 110,000 unique layer 2/3 neurons across retrosplenial, visual, somatosensory, and motor cortices in mice navigating a figure-8 maze spanning 47 days. Single-neuron spatial tuning properties followed a posterior-to-anterior gradient, with retros-plenial and visual cortices containing the highest proportions of spatially tuned neurons. This was dissociated from local functional coupling, which was strongest in somatosensory cortex. Population activity formed a low-dimensional manifold whose geometry mirrored the structure of the maze. Despite these regional differences, all four regions decorrelated with similar exponential timescales, and session-specific deviations from each regions decay trajectory were correlated across all pairwise region combinations, suggesting that drift was coordinated rather than independent across the dorsal cortex. This coordination persisted after controlling for shared behavioral fluctuations. Furthermore, drift was consistent with an orthogonal transformation of the population code that preserved the geometric relationships between spatial representations across sessions despite continuous drift in single-neuron tuning.

neuroscience↗

Cortex-Wide Cellular Imaging in Freely Locomoting Mice Using Cortex Camera Array Microscope (CortexCAM)

Understanding single-cell neuronal activity across multiple brain regions in the context of ethologically relevant behaviors is a major goal in systems neuroscience. We have engineered the Cortex Camera Array Microscope (CortexCAM), integrating four miniaturized fluorescence imaging microscopes to simultaneously capture cellular activity from contiguous fields of view spanning over 48 mm2 of the dorsal cortex. The CortexCAM is capable of imaging > 9000 individual neurons across much of the primary and secondary motor, somatosensory, visual, retrosplenial, and association cortices across both hemispheres of the dorsal cortex. The compact nature of the CortexCAM allows integration into a passive mechanical gantry system to form the mobile CortexCAM. The mobile CortexCAM allows volitional control of the animals translational motion (x, y) and rotational motion (yaw) in physical behavior arenas. We then use the mobile CortexCAM to perform cortex-wide cellular resolution imaging in freely locomoting mice performing alternating choice tasks, as well as during social interactions. Thus the CortexCAM allows studying cortex-wide cellular dynamics in behaviors that cannot be achieved in headfixed settings.

neuroscience↗

Pan-cortical cellular imaging in freely behaving mice using a miniaturized micro-camera array microscope (mini-MCAM)

Understanding how circuits in the brain simultaneously coordinate their activity to mediate complex ethnologically relevant behaviors requires recording neural activities from distributed populations of neurons in freely behaving animals. Current miniaturized imaging microscopes are typically limited to imaging a relatively small field of view, precluding the measurement of neural activities across multiple brain regions. Here we present a miniaturized micro-camera array microscope (mini-MCAM) that consists of four fluorescence imaging micro-cameras, each capable of capturing neural activity across a 4.5 mm x 2.55 mm field of view (FOV). Cumulatively, the mini-MCAM images over 30 mm2 area of sparsely expressed GCaMP6s neurons distributed throughout the dorsal cortex, in regions including the primary and secondary motor, somatosensory, visual, retrosplenial, and association cortices across both hemispheres. We demonstrate cortex-wide cellular resolution in vivo Calcium (Ca2+) imaging using the mini-MCAM in both head-fixed and freely behaving mice.

neuroscience↗

Computer vision guided open-source active commutator for neural imaging in freely behaving animals

Recently developed miniaturized neural recording devices that can monitor and perturb neural activity in freely behaving animals have significantly expanded our knowledge neural underpinning of complex behaviors. Most miniaturized neural interfaces require a wired connection for external power and data acquisition systems. The wires are required to be commutated through a slip ring to accommodate for twisting of the wire or tether and alleviate torsional stresses. The increased trend towards long term continuous neural recordings have spurred efforts to realize active commutators that can sense the torsional stress and actively rotation the slip ring to alleviate torsional stresses. Current solutions however require addition of sensing modules. Here we report on an active translating commutator that uses computer vision (CV) algorithms on behavioral imaging videos captured during the experiment to track the animals position and heading direction in real-time and uses this information to control the translation and rotation of a slipring commutator to accommodate for accumulated mouse heading orientation changes and position. The CV guided active commutator has been extensively tested in three separate behavioral contexts and we show reliable cortex-wide imaging in a mouse in an open-field with a miniaturized widefield cortical imaging device. Active commutation resulted in no changes to measured neurophysiological signals. The active commutator is fully open source, can be assembled using readily available off-the-shelf components, and is compatible with a wide variety of miniaturized neurophotonic and neurophysiology devices.

neuroscience↗