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Slater, C.

Publications and source records attributed to Slater, C..

5 recordsLinked to original sources

Behavioral state-dependent norepinephrine dynamics in the primary somatosensory and prefrontal cortices during tactile detection tasks

Animals must integrate sensory information, ignore behaviorally irrelevant stimuli, and respond to behaviorally relevant stimuli to find food, find mates, avoid predators, and ultimately survive. In mammals, these goal-directed behaviors require the coordinated activity of many brain regions, including sensory and prefrontal cortices and neuromodulatory brainstem nuclei like the locus coeruleus (LC), which is the brains primary source of norepinephrine (NE). NE release resulting from LC activity and arousal indexed by pupil size exert strong influences on goal-directed behavior. We explored the relationships between pupil size, cortical noradrenergic dynamics, and behavior in a tactile signal detection task. We monitored pupil dynamics and fluorescent GRABNE signals in somatosensory and medial prefrontal cortices simultaneously during task execution and found that pupil size and synchronization of GRABNE signals at baseline were strong predictors of whether animals chose to respond. Baseline and post-reward cortical GRABNE levels varied strongly with pupil-linked arousal. We also employed a generalized linear model - hidden Markov model (GLM-HMM) framework to identify distinct, stable behavioral states throughout the task that characterize task performance. We found distinct psychometric curves, task-related pupil dynamics, and cortical NE dynamics across these behavioral states. Significance StatementBehavioral state strongly shapes goal-directed behavior, which in turn depends on the coordinated activity of distributed brain regions, including the sensory and prefrontal cortices. By simultaneously measuring pupil size and cortical noradrenergic dynamics, and by identifying psychophysically distinct behavioral states during a tactile detection task, this study establishes links between pupil-linked arousal, norepinephrine signaling in somatosensory and prefrontal cortices, and trial outcomes. These findings provide new insight into how the locus coeruleus - norepinephrine system regulates perception and decision-making.

neuroscience↗

The Tiling Algorithm - A general method for structural characterization of accurate long DNA sequence reads: application to AAV genome sequences.

Adeno-associated virus (AAV), a common vector used in human gene therapy, is challenging for DNA sequencing for several reasons. First, AAVs replication cycle results in structural rearrangements. Specifically, the inverted terminal repeat (ITR) at each end of the genome as well as the genetic payload can invert independently. Second, the ITR can prime DNA replication of the entire viral genome in the gap filling step of a sequencing library preparation protocol. Third, the AAV manufacturing process can produce small fractions of viral particles containing host cell DNA and/or fragments of the helper plasmids. And finally, short read sequencing is ill suited for the characterization of repetitive sequences and structural rearrangements involving several hundred nucleotides. Pacific Biosciences (PacBio) long-read sequencers are capable of full length, accurate, single molecule sequencing of AAV viral genomes, which addresses the challenge of working with repetitive sequences. However, sequence analysis methods based on alignment to a reference are confounded by the other three challenges above. We present a simple algorithm for determining the arrangement of functional elements of single DNA molecules which can be aggregated to provide a sensitive measure of the population of sequences in a sample, including minor species. Using data from four publicly available datasets, we demonstrate our algorithm is able to characterize nearly all of the species in the AAV samples.

bioinformatics↗

Brain-wide cell-type-specific noradrenergic modulation of the transcriptome

Neuromodulatory systems such as the locus coeruleus-norepinephrine (LC-NE) system exert a widespread influence on brain function, yet the transcriptional consequences of such neuromodulatory perturbations remain largely unknown across the many unique cell types in the brain. In this study, we establish a generalizable framework to map brain-wide, cell-type-specific gene expression changes in mice following in vivo chemogenetic activation or inhibition of LC neurons. Single-nucleus RNA sequencing revealed that LC perturbation induces widespread but highly cell type- and region-specific transcriptional program changes, shaped by the distribution of adrenergic receptor subtypes. These findings support a model in which a shared global signal of neuromodulatory tone can produce discrete, context-dependent cellular outcomes through distinct molecular gating mechanisms of cell-type-specific adrenergic receptor subtype combinations. By establishing gene expression as a quantifiable metric of neuromodulatory control, this study lays the foundation for transcriptionally informed interventions capable of modulating brain functions with cellular precision.

neuroscience↗

Bidirectional Modulation of Somatostatin-expressing Interneurons in the Basolateral Amygdala Reduces Neuropathic Pain Perception in Mice

Neuropathic pain is characterized by mechanical allodynia and thermal (heat and cold) hypersensitivity, yet the underlying neural mechanisms remain poorly understood. This study examines the role of inhibitory interneurons in the basolateral amygdala (BLA) in modulating pain perception following nerve injury. Chemogenetic excitation of parvalbumin-positive (PV+) interneurons significantly alleviated mechanical allodynia but had minimal effects on thermal hypersensitivity. However, inhibition of PV+ interneurons did not produce significant changes in pain sensitivity, suggesting that reductions in perisomatic inhibition do not contribute to chronic pain states. In contrast, bidirectional modulation of somatostatin-positive (SST+) interneurons influenced pain perception in a modality-specific manner. Both excitation and inhibition of SST+ interneurons alleviated mechanical allodynia, indicating a potential compensatory role in nociceptive processing. Additionally, SST+ neuron excitation reduced cold hypersensitivity without affecting heat hypersensitivity, whereas inhibition improved heat hypersensitivity but not cold responses. These findings suggest that, in addition to PV+ neurons, SST+ interneurons in the BLA play a complex role in modulating neuropathic pain following nerve injury and may serve as a potential target for future neuromodulation interventions in chronic pain management.

neuroscience↗

Alpha modulation of spiking activity across multiple brain regions in mice performing a tactile selective detection task

Many cognitive and sensory processes are characterized by strong relationships between the timing of neuronal spiking and the phase of ongoing local field potential oscillations. The coupling of neuronal spiking in neocortex to the phase of alpha oscillations (8-12 Hz) has been well studied in nonhuman primates but remains largely unexplored in other mammals. How this alpha modulation of spiking differs between brain areas and cell types, as well as its role in sensory processing and decision making, are not well understood. We used Neuropixels 1.0 probes to chronically record neural activity from somatosensory cortex, prefrontal cortex, striatum, and amygdala in mice performing a whisker-based selective detection task. We observed strong spontaneous alpha modulation of single-neuron spiking activity during inter-trial intervals while mice performed the task. The prevalence and strength of alpha phase modulation differed significantly across regions and between cell types. Phase modulated neurons exhibited stronger responses to both go and no-go stimuli, as well as stronger motor- and reward-related changes in firing rate, than their unmodulated counterparts. The increased responsiveness of phase modulated neurons suggests they are innervated by more diverse populations. Alpha modulation of neuronal spiking during baseline activity also correlated with task performance. In particular, many neurons exhibited strong alpha modulation before correct trials, but not before incorrect trials. These data suggest that dysregulation of spiking activity with respect to alpha oscillations may characterize lapses in attention.

neuroscience↗