Auditory-evoked EEG signals contain rich temporal and cognitive features that reflect both the identity of individuals and their neural response to external stimuli. Traditional unimodal approaches often fail to fully leverage this multidimensional information fully, limiting their effectiveness in real-world biometric and neurocognitive applications. This study aims to develop a unified deep learning model capable of jointly performing biometric identification, auditory stimulus language classification, and device modality recognition, thereby exploiting both physiological and cognitive dimensions of auditory-evoked EEG. We introduce TriNet-MTL (Triple-Task Neural Transformer for Multitask Learning), a multi-branch deep learning framework composed of a shared temporal encoder and a transformer-based sequence modeling unit, trained and validated on auditory-evoked EEG data from 20 human participants (16 males and 4 females). The architecture is designed to simultaneously learn task-specific features via th...

Neurite outgrowth is essential for neural circuit formation and is tightly regulated by secreted factors and their receptors. The secreted extracellular domain of the amyloid precursor protein (sAPPα) has been shown to modulate neurite outgrowth. Recently, the gamma amino butyric acid receptor type-B subunit 1a (GABABR1a) was identified as an sAPPα binding partner that mediates its effects on synaptic transmission. Here, we investigated whether this interaction also regulates neurite outgrowth. In mouse primary hippocampal neurons of either sex, the GABABR agonist baclofen reduced axon length; whereas, its antagonist CGP54626 increased axon length in primary hippocampal neurons. Moreover, GABABR1a knockout increased axon length and abolished the effect of baclofen. Application of sAPPα reduced axon length, an effect that required the presence of both GABABR1a and the extension domain of sAPPα, which mediates its binding to GABABR1a. Similarly, the APP 17mer peptide, which is sufficient to bind GABABR1a and...

Social cognition, central to emotional and cognitive well-being, is particularly vulnerable to aging, where impairments can lead to isolation and functional decline. Despite compelling evidence that altered social behavior is associated with cognitive decline and dementia risk, experimental strategies for testing causative links remain scarce. To address this gap, we aimed to establish a rat model for research on social neurocognitive aging. We conducted a large-scale behavioral study in 169 male young (6 months) and aged (24-25 months) Long-Evans rats. In order to explore potential relationships among aging outcomes, we first documented individual differences in a widely validated water maze test of hippocampal learning and memory. Sociability and social novelty were then evaluated in the same subjects using the three-chamber social interaction test. Aging induced a selective shift in social novelty preference, marked by a striking familiarity bias in a substantial subpopulation of old rats, while sociabi...

The transition to virtual conferences and poster presentations poses its own set of challenges, especially for those new to this format. Having recently participated in Neuroscience 2022, which was my first virtual presentation, I'm eager to share some insights and practical advice.

Dopaminergic inputs to various brain regions, such as the striatum, orbitofrontal cortex, and amygdala, play a critical role in processing reward acquisition information. While reward-related activity is also observed more broadly in motor, parietal, and hippocampal regions, the functional significance and potential hierarchy of reward-related representation across these latter areas remain unclear. We investigated this by quantifying neural predictive power using machine learning. Specifically, neural activity was examined in six brain areas—the primary and secondary motor cortices (M1 and M2), posterior parietal cortex (PPC), dorsal and ventral CA1 (dCA1 and vCA1), and lateral entorhinal cortex (LEC)—in male rats performing a self-initiated left–right choice task. Machine learning models classified rewarded versus nonrewarded trials based on neuronal firing properties significantly above chance for all regions. Crucially, classification revealed a clear performance gradient, forming a functional hierarch...

Neurexins (Nrxns) are presynaptic cell adhesion molecules essential for synapse development and function. Of the many neurexin isoforms, only β-Nrxns contain the histidine-rich domain (HRD). While the HRD has been implicated in several pathological contexts, its normal physiological role remains unclear. To address this, we used a CRISPR-Cas9 method to generate a new mouse line expressing in-frame truncated Nrxn1β lacking the HRD. We found that HRD deletion did not affect mouse viability, gross brain development, or general behavior of either sex. However, loss of the HRD significantly altered neuroligin-1-dependent excitatory, but not inhibitory, presynaptic differentiation in primary cultured neurons. Moreover, this deletion affected presynaptic short-term plasticity, but not basal synaptic transmission, at hippocampal Schaffer collateral→CA1 synapses. These findings identify the Nrxn1β HRD as a potential contributor to excitatory presynaptic organization and function, providing new insight into the mole...

Vestibular dysfunction constitutes a major medical concern, and regeneration of hair cells (HCs) is a primary target of gene therapy aimed at restoring vestibular functions. Thus far, therapeutic trials in animal models targeting vestibular loss associated with genetic diseases have yielded variable and partial results, and the functional identity and quantity of HCs required to restore minimal or normal vestibular function remain undefined. Indeed, direct comparisons between structural pathology and quantitative assessments of vestibular dysfunctions are lacking in humans and are rather limited in animal models, representing a significant gap in current knowledge. Here, we present an innovative methodology to bridge the gap between HC integrity and functional vestibular loss in individual mice of either sex. Gradual vestibular deficits were induced through a dose-dependent ototoxic lesion, quantified with canal or utricular-specific vestibulo-ocular reflex tests, and were then correlated in all individual...

Measuring neurite length is crucial in neurobiology because it provides valuable insights into the growth, development, and function of neurons. In particular, neurite length is fundamental to study neuronal development and differentiation, neurons responses to drugs, neurodegenerative diseases and neuronal plasticity. Surprisingly, there is currently a lack of tools for high-throughput neurite analysis. In this article, we present CABaNe, as an open-source, high-throughput, rule-based ImageJ macro for cell analysis, including their neurite length. This macro possesses a graphical interface, metadata production, as well as verification means before and after analysis. Rule-based and machine learning-based programming have been tested for cell identification. Cell tested were N2A, a mouse neuroblastoma cell line. After testing, we had better precision and adaptability using rule-based cell identification. We challenged CABaNe with currently used techniques, which are manual or assisted. When tested on a sma...

There are a wide variety of commercially available antibodies for labeling microglial cells based on different protein targets, as well as antibodies for the same protein target made in different species. While this array of targets and hosts allows for flexibility in immunohistochemical experiments, it is important to validate that different antibodies provide comparable and accurate immunodetection prior to experimental data collection. We found that a commercially available anti-Iba1 antibody, made in goat, produces irregular staining patterns in specific regions of the mouse brain in both sexes, prompting a further investigation into the phenomenon. This Iba1-goat antibody displayed increased numbers of labeled cells when compared with expression of a CX3CR1-GFP reporter and IHC detection of P2RY12, two common microglial markers. Furthermore, immunodetection by other common anti-Iba1 antibodies made in rabbit and chicken did not display the excessive cell labeling when compared with the CX3CR1-GFP repo...

Neurite outgrowth is essential for neural circuit formation and is tightly regulated by secreted factors and their receptors. The secreted extracellular domain of the amyloid precursor protein (sAPPα) has been shown to modulate neurite outgrowth. Recently, the gamma amino butyric acid receptor type-B subunit 1a (GABABR1a) was identified as an sAPPα binding partner that mediates its effects on synaptic transmission. Here, we investigated whether this interaction also regulates neurite outgrowth. In mouse primary hippocampal neurons of either sex, the GABABR agonist baclofen reduced axon length; whereas its antagonist CGP54626 increased axon length in primary hippocampal neurons. Moreover, GABABR1a knock-out increased axon length and abolished the effect of baclofen. Application of sAPPα reduced axon length, an effect that required the presence of both GABABR1a and the extension domain of sAPPα, which mediates its binding to GABABR1a. Similarly, the APP 17mer peptide, which is sufficient to bind GABABR1a and...