Cortical tracking of the speech envelope is an emerging, noninvasive measure of neurophysiological processing of speech that is being widely adopted. It demonstrates good ecological validity, as it allows researchers to study human processing of continuous, naturalistic speech containing dynamic spectrotemporal variations and rich linguistic content. While measures of cortical tracking have strong clinical and research applications, there is a lack of research documenting the reliability of these measures, including how they are affected by the stimulus and how the stimulus is represented, as well as electroencephalography (EEG) acquisition and analysis parameters. In this study, we measured the test–retest reliability of cortical tracking of the speech envelope across different stimuli (an audiobook vs a podcast), stimulus features (broadband envelope and its derivative, multiband envelope and its derivative), reference electrodes (average mastoid vs common average reference), and EEG frequency bands (del...

Sleep is a vital physiological phenomenon observed among almost all organisms. Although its exact purpose remains elusive, sleep has been linked to memory consolidation. In our present study, we investigated the role of sleep quality on sleep-dependent memory consolidation. Previous studies have shown that tequila , a serine protease, affects long-term memory (LTM) consolidation in flies. In the present study, we identified that the hypomorphic mutation in the tequila gene ( tequilaf01792 ) leads to increased daytime sleep fragmentation at a very early age in male flies. Intrigued by this observation, we delved into further understanding the role of tequila in sleep-dependent memory consolidation by manipulating sleep duration using pharmacological methods such as GABA-A agonist. Inducing sleep using GABA-A agonist resulted in improved sleep during the day. This further led to a significant improvement in the LTM of these flies when compared with the vehicle-treated flies. In conclusion, daytime-dependent ...

Every neuron contains the same genomic information, but its complement of proteins is the product of countless neuron-specific steps including pre-mRNA splicing. Despite advances in RNA sequencing techniques, pre-mRNA splicing biases that favor one isoform over another are largely inscrutable in live neurons in situ. Here, in Drosophila , we developed bichromatic fluorescent reporters to investigate alternative splicing of cacophony ( cac )—a gene that codes the pore-forming α1 subunit of the primary neuronal voltage-gated Ca2+ channel (VGCC). These reporters revealed a neuron-specific pattern of exon biases, highly consistent from one animal to the next, suggesting that each neuron splices a unique and consistent portfolio of VGCC isoforms. Stereotypical patterns were observed within motor neurons and multidendritic sensory neurons of female larvae and also within mushroom body Kenyon cells of female adults. In a validation step, we demonstrated that exon splice bias reporting was not dependent on the cho...

Adolescent nicotine use is particularly concerning due to increased susceptibility to long-term effects and dependence during this critical developmental period. This study investigates the therapeutic effects of thiamine on nicotine withdrawal-induced anxiety, anhedonia, and depression in rats. Adolescent rats received nicotine (2 mg/kg, s.c.) for 21 d, followed by 21 d of withdrawal. Thiamine (25 or 50 mg/kg, i.p.) was administered during exposure and withdrawal. Behavioral assessments were used to evaluate anxiety- and depressive-like symptoms, and biochemical analyses measured oxidative stress markers, serotonin levels, MAO activity, BDNF, and GFAP as indicators of neuroinflammation in the prefrontal cortex. Nicotine withdrawal significantly elevated anxiety-, depression-, and anhedonia-like behaviors, increased oxidative stress, and upregulated MAO-A activity and GFAP expression, indicating neuroinflammatory effects. Notably, thiamine administration during both nicotine exposure and withdrawal effecti...

The development of motor control over sensory organs is a critical milestone, enabling active exploration and shaping of the sensory environment. Whether the onset of sensory organ motor control directly influences the development of corresponding sensory cortices remains unknown. Here, we confirm and exploit the late onset of whisking behavior in mice to address this question in the somatosensory system. Using ex vivo electrophysiology, we describe a transient increase in the intrinsic excitability of excitatory neurons in layer IV of the barrel cortex, which processes whisker input, immediately following the onset of active whisking on postnatal days 13 and 14. This increase in neuronal gain is specific to layer IV, independent of changes in synaptic strength, and requires prior sensory experience. Further, these effects are not expressed in inhibitory interneurons in barrel cortex. The transient increase in excitability is not evident in layer II/III of barrel cortex or in the visual cortex upon eye ope...

Fiber photometry is a neuroscience technique that can continuously monitor in vivo fluorescence to assess population neural activity or neuropeptide/transmitter release in freely behaving animals. Despite the widespread adoption of this technique, methods to statistically analyze data in an unbiased, objective, and easily adopted manner are lacking. Various pipelines for data analysis exist, but they are often system specific, are only for preprocessing data, and/or lack usability. Current post hoc statistical approaches involve inadvertently biased user-defined time-binned averages or area under the curve analysis. To date, no post hoc user-friendly tool with few assumptions for a standardized unbiased analysis exists, yet such a tool would improve reproducibility and statistical reliability for all users. Hence, we have developed a user-friendly post hoc statistical analysis package in Python that is easily downloaded and applied to data from any fiber photometry system. This Fiber Photometry Post Hoc An...

Comparative analyses of locomotor behavior and cellular electrical properties between wild-type and mutant Caenorhabditis elegans are crucial for exploring the gene basis of behaviors and the underlying cellular mechanisms. Although many tools have been developed by research labs and companies, their application is often hindered by implementation difficulties or lack of features specifically suited for C. elegans . Our system addresses these challenges with three key components: WormTracker , SleepTracker , and Action Potential (AP) Analyzer . WormTracker accurately quantifies a comprehensive set of locomotor and body bending metrics, incorporates user-identified dorsal and ventral orientation based on microscopic observation, continuously tracks the animal using a motorized stage, and seamlessly integrates external devices, such as a light source for optogenetic stimulation. SleepTracker detects and quantifies sleep-like behavior in freely moving animals. AP Analyzer assesses the resting membrane potenti...

Despite the vivid experience of homogeneous vision, our visual system is inherently endowed with highly inhomogeneous structures. Although the temporal characteristics of visual responses vary with eccentricity, the connection between this variation, the speed of visual processing, and its underlying neurophysiological mechanisms remains a topic of debate. Here, we performed simultaneous recordings of high-precision gaze positions and EEG activity to investigate how foveal and perifoveal stimulations impact reaction times (RTs) and visual evoked potentials (VEPs). Volunteers discriminated the position and orientation of a U-shaped figure with the aperture facing either upward or downward. Stimuli were presented briefly (50 ms) either in the foveola (0.33°) or perifovea (6.5°), to the right or left of the fixation point. Stimulus size in the perifovea condition was adjusted according to the cortical magnification factor (stimulus size: 0.2° and 0.75° for the foveola and perifovea conditions, respectively). ...

In the article “A Preprocessing Toolbox for 2-Photon Subcellular Calcium Imaging,” by Anqi Jiang, Chong Zhao, and Mark E. J. …

The interface barrier between the brain surface and the adjacent meninges is important for regulating exchanges of fluid, protein, and immune cells between the CNS and periphery. However, the cell types that form this important interface are not yet fully defined. To address this limitation, we used single-cell RNA sequencing (scRNA-seq) and single-cell spatial transcriptomics together with morphological lineage tracing and immunostaining to describe the cell types forming the interface barrier of the adult murine cortex. We show that the cortical interface is composed of three major cell types, leptomeningeal cells, border astrocytes, and tissue-resident macrophages. On the nonparenchymal side, the interface is composed of transcriptionally distinct PDGFRα-positive leptomeningeal cells that are intermingled with macrophages. This leptomeningeal layer is lined by a population of transcriptionally distinct border astrocytes. The interface neighborhood is rich in growth factor mRNAs, including many leptomeni...