In everyday life, ambient sounds can disrupt our concentration, interfere with task performance, and contribute to mental fatigue. Even when not actively attended to, salient or changing sounds in the environment can involuntarily divert attention. Understanding how the brain responds to these real-world auditory distractions is essential for evaluating the cognitive consequences of environmental noise. In this study, we recorded electroencephalography while participants performed different tasks during prolonged exposure to a complex urban soundscape. We identified naturally occurring, acoustically salient events and analyzed the corresponding event-related potentials (ERPs). Auditory spectral novelty reliably elicited a P3a response (250–350 ms), reflecting robust attentional capture by novel environmental sounds. In contrast, the reorienting negativity (RON) window (450–600 ms) showed no consistent modulation, possibly due to the continuous and largely behaviorally irrelevant nature of the soundscape. P...

Our ability to shift from one emotion to the next allows us to adapt our behaviors to a constantly changing and often uncertain environment. Although previous studies have identified cortical and subcortical regions involved in affective responding, none have shown how these regions track and represent transitions between different emotional states, nor how such responses are modulated based on the recent emotional context. To study this, we commissioned new musical pieces designed to systematically move participants ( N  = 39, 20 males and 19 females) through different emotional states during fMRI and to manipulate the emotional context in which different participants heard a musical motif. Using a combination of data-driven (hidden Markov modeling) and hypothesis-driven methods, we confirmed that spatiotemporal patterns of activation along the temporoparietal axis reflect transitions between music-evoked emotions. We found that the spatial and temporal signatures of these neural response patterns, as wel...

The prepositus hypoglossi nucleus (PHN), involved in horizontal gaze control, contributes to this function via cooperation with the vestibulocerebellum (VC). Furthermore, some PHN neurons have been observed to project to cerebellar regions outside the VC. We previously reported a neuronal population in the ventral caudal PHN that projects to lobules III–V of the anterior vermis or to the cerebellar hemispheric crus. Because the properties of these neurons have not been clarified, this study aimed to determine their localization, projections, and electrophysiological and morphological characteristics in male rats. Tracing experiments revealed that these neurons were clustered within the ventral caudal PHN, approximately between the bregma −12.72 and −12.00 mm, and did not project to the uvula/nodulus (UN), which is part of the VC. Whole-cell recordings and morphological experiments revealed that these PHN neurons exhibited high input capacitance, low input resistance, low-frequency firing, prominent voltage...

It has long been hypothesized that the nervous system uses the direction of gravity to align the various sensory systems when interacting with the external world. In line with this hypothesis, systematic drift in hand-path orientation was recently observed during targeted arm motions performed with eyes closed in weightlessness or, on Earth, for longitudinal movements in a supine posture. No such drift was observed in upright posture on Earth. But the precise conditions under which participants exhibit such drift, and the factors that influence the magnitude of the drift, are not yet known. The objective of our study was to investigate if the upright posture, by virtue of being at a biomechanical singularity induced by the force of gravity, represents a unique condition in which drift in hand-path orientation is prevented. Human participants (male and female) performed sequences of repeated point-to-point arm movements between two visual targets aligned with the longitudinal body axis, first with eyes open...

Virtual reality (VR) has gained popularity in recent years, integrating with conventional music stimulation (MS), action observation (AO), and motor imagination (MI). It offers promising opportunities for developing innovative rehabilitation treatments, though the mechanisms underlying these effects remain unclear. This study aims to compare brain activation and network mechanisms following the fusion of MS, AO, and MI with VR. Fifty healthy participants were recruited and underwent functional near-infrared spectroscopy synchronization with three VR tasks: MS (VRMS), AO (VRAO), and MI (VRMI). The results indicate that VRMS significantly enhances functional connectivity of the bilateral primary sensory cortex (S1), premotor cortex, and supplementary motor area (PM&SMA) compared with VRAO and VRMI. Furthermore, the interaction among the bilateral PM&SMA, right dorsolateral prefrontal cortex, and right primary motor cortex (M1) regions is notably stronger with VRMS than with the other VR tasks. These findings...

Animal behavior is crucial for understanding both normal brain function and dysfunction. To facilitate behavior analysis of mice within their home environments, we developed DeepEthoProfile, an open-source software powered by a deep convolutional neural network for efficient behavior classification. DeepEthoProfile requires no spatial cues for either training or processing and is designed to perform reliably under real laboratory conditions, tolerating variations in lighting and cage bedding. For data collection, we introduce EthoProfiler, a mobile cage rack system capable of simultaneously recording up to 10 singly housed mice. We used 36 h of manually annotated video data sampled in 5 min clips from a 48 h video database of 10 mice. This published dataset provides a reference that can facilitate further research. DeepEthoProfile achieved an overall classification accuracy of over 83%, comparable with human-level accuracy. The model also performed on par with other state-of-the-art solutions on another pu...

There is a growing imperative to understand the neurophysiological impact of our rapidly changing and diverse technological, social, chemical, and physical environments. To untangle the multidimensional and interacting effects requires data at scale across diverse populations, taking measurement out of a controlled lab environment and into the field. Electroencephalography (EEG), which has correlates with various environmental factors as well as cognitive and mental health outcomes, has the advantage of both portability and cost-effectiveness for this purpose. However, with numerous field researchers spread across diverse locations, data quality issues and researcher idle time due to insufficient participants can quickly become unmanageable and expensive problems. In programs we have established in India and Tanzania, we demonstrate that with appropriate training, structured teams, and daily automated analysis and feedback on data quality, nonspecialists can reliably collect EEG data alongside various surv...

Neuroimaging data reveal that a functional locus ceruleus-noradrenaline (LC-NA) system is critical in maintaining cognitive performance during aging. However, older adults show reduced LC integrity and altered functional connectivity, demonstrating both structural declines and dysfunction. The LC-NA system mediates mechanisms of attention processing and eye tracking studies have shown that older adults are slower and more distractible compared with young adults in visual search tasks. Prior studies have shown that mindfulness meditation modulates LC noradrenergic activity, increases gray matter volume in the brainstem, and improves attentional control. Thus, in a preregistered longitudinal study, we investigated whether 30 d of guided mindfulness meditation using a mobile application improved attentional control measured with eye movements. We hypothesized that older adults would show greater benefits from the mindfulness intervention compared with young adults. In two oculomotor search tasks, we identifie...

Neuroscientists are increasingly initiating large-scale collaborations which bring together tens to hundreds of researchers. At this scale, such projects can tackle big challenges and engage diverse participants. Inspired by projects in mathematics, we set out to test the feasibility of widening access to such projects even further, by running a massively collaborative project in computational neuroscience. The key difference, with prior neuroscientific efforts, being that our entire project (code, results, and writing) was public from the outset, and that anyone could participate. To achieve this, we launched a public Git repository, with code for training spiking neural networks to solve a sound localization task via surrogate gradient descent. We then invited anyone, anywhere to use this code as a springboard for exploring questions of interest to them, and encouraged participants to share their work both asynchronously through Git and synchronously at online workshops. Our hope was that the resulting r...

In the mammalian visual system, three functionally distinct parallel processing streams extend from the retina to the visual thalamus and then to the visual cortex: magnocellular (M), parvocellular (P), and koniocellular (K). Tree shrews ( Tupaia belangeri ), a preprimate species, provide an advantageous model to study the K pathway in isolation because, while M and P pathways remain mixed in Lamina 1 (L1), L2, L4, and L5 of the lateral geniculate nucleus (LGN), L3 and L6 receive strictly K-input from the contralateral eye. Additionally, K-input laminae selectively receive glutamatergic axons from the superior colliculus. To reveal how cellular and synaptic properties of K geniculate laminae may differ from M/P laminae and how tectal input may shape the K relay to the cortex, we studied the morphology and connectivity of retinal and tectal terminals in pathway-specific laminae. While confirming that K laminae relay cells contain calbindin, we also found its expression in GABAergic cells across all laminae....