“Volatile working memory representations crystalize with practice” published in Nature

“Volatile working memory representations crystalize with practice” published in Nature

News
We are excited to announce the publication of our article, “Volatile working memory representations crystalize with practice,” in Nature. This work was a collaborative effort between the Golshani Lab at UCLA and the Vaziri Lab at The Rockefeller University, led by Dr. Arash Bellafard. The project’s success was driven by the dedication and inspiration of the Golshani Lab team, along with advanced two-photon imaging resources provided by the Vaziri Lab.In this study, we aimed to understand the neural dynamics of a large population of neurons involved in working memory (WM) over long timescales. We investigated the causality and stability of WM representations as animals became familiar with the task. To do this, we trained head-fixed mice to perform an olfactory delay-association WM task and recorded the activity of same population…
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“Drugs of abuse hijack a mesolimbic pathway that processes homeostatic need” published in Science

“Drugs of abuse hijack a mesolimbic pathway that processes homeostatic need” published in Science

News
We are excited to share that our paper entitled "Drugs of abuse hijack a mesolimbic pathway that processes homeostatic need" has been published in Science.Drugs of abuse produce pleasurable feelings and reinforce consummatory behavior directed toward their acquisition. These same properties are characteristic of natural rewards that satisfy innate needs, such as food or water. Decades of research has shown that brain systems processing natural rewards are also impacted by drugs of abuse at the physiological, circuit, cellular, and molecular levels. These findings raise the hypothesis that drugs of abuse cause addiction by “hijacking” a common reward pathway, ultimately promoting drug intake while curbing other healthy goals. However, the specific neural substrates for such a shared reward pathway remain unidentified.In this paper we identified the nucleus accumbens (NAc) as a…
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Unbounded scaling of dimensionality with neuron number

Optical Neurotechnology
Our paper entitled “Simultaneous, cortex-wide and cellular-resolution neuronal population dynamics reveal an unbounded scaling of dimensionality with neuron number” has been published in Neuron. The brain’s remarkable properties arise from collective activity of millions of neurons. Widespread application of dimensionality reduction to multi-neuron recordings implies that neural dynamics can be approximated by low-dimensional “latent” signals reflecting neural computations. However, what would be the biological utility of such a redundant and metabolically costly encoding scheme and what is the appropriate resolution and scale of neural recording to understand brain function? Imaging the activity of one million neurons at cellular resolution and near-simultaneously across mouse cortex, we demonstrate an unbounded scaling of dimensionality with neuron number. While half of the neural variance lies within sixteen behavior-related dimensions, we find this unbounded scaling…
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We Welcome Our New Postdoc Nikita Kulachenkov

News
Nikita received his Ph.D. in Physics and Mathematics from ITMO University, St. Petersburg, Russia where he worked on structure related optical switching in metal-organic frameworks. Most notably, he developed optical/PXRD methods for materials characterization, using table-top optics, fiber-optics, lasers, spectroscopy analysis. Now he will begin developing a novel type of miniaturized imaging system which combines high-speed multiphoton methods into the design. Congratulations and welcome to the team!
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New Article on bioRxiv: “Whole-brain neural substrates of behavioral variability in the larval zebrafish”

New Article on bioRxiv: “Whole-brain neural substrates of behavioral variability in the larval zebrafish”

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We are happy to announce that a new manuscript entitled “Whole-brain neural substrates of behavioral variability in the larval zebrafish” has been uploaded to the bioRxiv preprint server. Animals engaged in naturalistic behavior can exhibit a large degree of behavioral variability even under sensory invariant conditions. Such behavioral variability can include not only variations of the same behavior, but also variability across qualitatively different behaviors driven by divergent cognitive states, such as fight-or-flight decisions. However, the neural circuit mechanisms that generate such divergent behaviors across trials are not well understood. To investigate this question, here we studied the visual-evoked responses of larval zebrafish to moving objects of various sizes, which we found exhibited highly variable and divergent responses across repetitions of the same stimulus.In this work, we present a Fourier…
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New Article on bioRxiv: “A Systematically Optimized Miniaturized Mesoscope (SOMM) for large-scale calcium imaging in freely moving mice”

New Article on bioRxiv: “A Systematically Optimized Miniaturized Mesoscope (SOMM) for large-scale calcium imaging in freely moving mice”

News
We are happy to announce that a new manuscript entitled “A Systematically Optimized Miniaturized Mesoscope (SOMM) for large-scale calcium imaging in freely moving mice” has been uploaded to the bioRxiv preprint server. Understanding how neuronal dynamics gives rise to ethologically relevant behavior requires recording of neuronal population activity via technologies that are compatible with unconstrained animal behavior. However, realizations of cellular resolution head mounted microscopes for mice have been based on conventional microscope designs that feature various forms of ad-hoc miniaturization and weight reduction measures necessary for compatibility with the weight-limits for free animal behavior. As a result, they have typically remained limited to a small field of view (FOV) or low resolution, a shallow depth range and often remain susceptible to motion-induced artifacts. We present a systematically optimized miniaturized…
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New Article on bioRxiv: “Simultaneous, cortex-wide and cellular-resolution neuronal population dynamics reveal an unbounded scaling of dimensionality with neuron number”

New Article on bioRxiv: “Simultaneous, cortex-wide and cellular-resolution neuronal population dynamics reveal an unbounded scaling of dimensionality with neuron number”

New Publication, News
We are happy to announce that a new manuscript entitled “Simultaneous, cortex-wide and cellular-resolution neuronal population dynamics reveal an unbounded scaling of dimensionality with neuron number” has been uploaded to the bioRxiv preprint server. The brain’s remarkable properties arise from collective activity of millions of neurons. Widespread application of dimensionality reduction to multi-neuron recordings implies that neural dynamics can be approximated by low-dimensional “latent” signals reflecting neural computations. However, what would be the biological utility of such a redundant and metabolically costly encoding scheme and what is the appropriate resolution and scale of neural recording to understand brain function? Imaging the activity of one million neurons at cellular resolution and near-simultaneously across mouse cortex, we demonstrate an unbounded scaling of dimensionality with neuron number. While half of the neural variance…
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Mesoscale volumetric light-field (MesoLF) imaging of neuroactivity across cortical areas at 18 Hz

Optical Neurotechnology, Research
Our paper entitled “Mesoscale volumetric light field (MesoLF) imaging of neuroactivity across cortical areas at 18 Hz” has been published in Nature Methods. We present a modular, mesoscale light field (MesoLF) imaging hardware and software solution that allows recording from thousands of neurons within volumes of ⌀4 × 0.2 mm, located at up to 350 µm depth in the mouse cortex, at 18 volumes per second (Video 1). Using our optical design and computational approach we show recording of ~10,000 neurons across multiple cortical areas in mice using workstation-grade computing resources. Video 1 | Animated perspective rendering of neuron positions and calcium activity recorded using MesoLF in mouse cortex. Field of view: ⌀4000 × 200 µm. Depth range: 0–200 µm. Recording frame rate: 18 Hz. Real-time recording duration: 405 s. Playback speed-up: 25×. Labelling construct: AAV9-TRE3-2xsomaGCaMP7f. Information…
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“Mesoscale volumetric light-field (MesoLF) imaging of neuroactivity across cortical areas at 18 Hz” published in Nature Methods

“Mesoscale volumetric light-field (MesoLF) imaging of neuroactivity across cortical areas at 18 Hz” published in Nature Methods

New Publication, News
Our article entitled “Mesoscale volumetric light field (MesoLF) imaging of neuroactivity across cortical areas at 18 Hz” has been published in Nature Methods. Information flow across mesoscale, i.e., multi-millimeter-sized regions of the mammalian cortex is a key feature of high-level cognition and is known to underlie complex behaviors. Yet, tracing this information flow in a volumetric fashion at a cellular resolution and high speed has remained challenging. This is primarily because most established neuronal activity imaging methods, such as two-photon microscopy, rely on time-consuming point-by-point scanning of an excitation beam focus to read out neuronal activity, as reported by the fluorescence rate of designer proteins known as genetically encoded calcium indicators (GECIs). We present a modular, mesoscale light field (MesoLF) imaging hardware and software solution that allows recording from thousands of…
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“Dynamic Processing of Hunger and Thirst by Common Mesolimbic Neural Ensembles” published in PNAS

“Dynamic Processing of Hunger and Thirst by Common Mesolimbic Neural Ensembles” published in PNAS

News
We are happy to share that our paper "Dynamic Processing of Hunger and Thirst by Common Mesolimbic Neural Ensembles" has been published in PNAS. Eating and drinking both activate a subset of accumbal neurons but it was unknown whether same or different neurons represent distinct need states. We set out to study the state-coding principles of hunger and thirst in the nucleus accumbens (NAc) using two-photon calcium imaging of neural activity in awake mice during feeding and drinking. We find that highly overlapping sets of individual D1 and D2 neurons respond similarly to food and water with specific subsets showing distinct temporal activity patterns throughout the consummatory phase. Modulating D1 and D2 neurons elicited analogous effects on both behavioral programs. These data suggest a general role of NAc to regulate…
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