Objectives: Converging evidence indicates beneficial effects of aerobic exercise on motor learning performance. Underlying mechanisms might be an impact of aerobic exercise on neuroplasticity and cortical excitability. Evidence suggests that motor learning and cortical excitability alterations correlate with the intensity of aerobic exercise and the activity level of participants. Thus, this study aims to investigate the effects of different aerobic exercise intensities on motor learning and cortical excitability in sedentary individuals. Methods : The study was conducted in a cross-over and double-blind design. 26 healthy sedentary individuals (13 women and 13 men) performed a motor learning task and received cortical excitability assessment before and after a single session of low-, moderate-, high-intensity aerobic exercise or a control intervention. Results : The study revealed that motor learning performance and cortical excitability were significantly enhanced in the moderate-intensity aerobic exerci...

Most human navigation studies in MRI rely on virtual navigation. However, the necessary supine position in MRI makes it fundamentally different from daily ecological navigation. Nonetheless, until now, no study has assessed whether differences in physical body orientation (BO) affect participants’ experienced BO during virtual navigation. Here, combining an immersive virtual reality (VR) navigation task with subjective BO measures and implicit behavioral measures, we demonstrate that physical BO (either standing or supine) modulates experienced BO. Also, we show that standing upright BO is preferred during spatial navigation: participants were more likely to experience a standing BO and were better at spatial navigation when standing upright. Importantly, we report that showing a supine virtual agent reduces the conflict between the preferred BO and physical supine BO. Our study provides critical, but missing, information regarding experienced BO during virtual navigation, which should be considered cautio...

Objective: To develop a deep learning-based automatic system with reliable performance in detecting interictal epileptiform discharges (IEDs) from scalp electroencephalograms (EEGs). Methods: For the present study, 484 raw scalp EEG recordings were included, standardized, and split into 406 for training and 78 for testing. Two neurophysiologists individually annotated the recordings for training in channel-wise manner. Annotations were divided into segments, on which 9 deep neural networks (DNNs) were trained for the multi-classification of IED, artifact and background. The fitted IED detectors were then evaluated on 78 EEG recordings with IED events fully annotated by 3 experts independently (majority agreement). A two-montage-based decision mechanism (TMDM) was designed to determine whether an IED event occurred at a single time instant. Area under the precision-recall curve (AUPRC), as well as false positive rates, F1 scores, and Kappa agreement scores for sensitivity = 0.8 were estimated. Results: In...

Animals exhibit context-dependent behavioral decisions that are mediated by specific motor circuits. In social species these decisions are often influenced by social status. Although social status-dependent neural plasticity of motor circuits has been investigated in vertebrates, little is known of how cellular plasticity translates into differences in motor activity. Here, we used zebrafish ( Danio rerio ) as a model organism to examine how social dominance influences the activation of swimming and the Mauthner-mediated startle escape behaviors. We show that the status-dependent shift in behavior patterns whereby dominants increase swimming and reduce sensitivity of startle escape while subordinates reduce their swimming and increase startle sensitivity is regulated by the synergistic interactions of dopaminergic, glycinergic, and GABAergic inputs to shift the balance of activation of the underlying motor circuits. This shift is driven by socially induced differences in expression of dopaminergic receptor...

Stress has been identified as a major contributor to human disease and is postulated to play a substantial role in epileptogenesis. In a significant proportion of individuals with epilepsy, sensitivity to stressful events contributes to dynamic symptomatic burden, notably seizure occurrence and frequency, and presence and severity of psychiatric comorbidities [anxiety, depression, posttraumatic stress disorder (PTSD)]. Here, we review this complex relationship between stress and epilepsy using clinical data and highlight key neurobiological mechanisms including the hypothalamic-pituitary-adrenal (HPA) axis dysfunction, altered neuroplasticity within limbic system structures, and alterations in neurochemical pathways such as brain-derived neurotrophic factor (BNDF) linking epilepsy and stress. We discuss current clinical management approaches of stress that help optimize seizure control and prevention, as well as psychiatric comorbidities associated with epilepsy. We propose that various shared mechanisms o...

Brains implement some of the most complex functions of living systems including intelligence, decision-making, learning, and sentience, which is the capacity for subjective experience. To better understand these and other cognitive functions, neuroscientists have meticulously delineated the brain’s microcircuitry and pathways to relate mental phenomena with discrete neural substrates. One of the driving forces behind what has become an ever-expanding literature on functional neuroanatomy is the longstanding assumption that all mental actions and states can be localized, mapped, or otherwise attributed to specific configurations of brain matter. Consistent with this assumption, by selectively damaging or stimulating brain regions, one could suppress or evoke cognitive or behavioral responses that confirmed suspected structure-function relationships. While this approach has not helped explain why mind emerges from matter, its historical success is a crowning achievement for the field of cognitive neuroscienc...

Because of the legalization of Cannabis in many jurisdictions and the trend of increasing Δ9-tetrahydrocannabinol (THC) content in Cannabis products, an urgent need exists to understand the impact of Cannabis use during pregnancy on fetal neurodevelopment and behavior. To this end, we exposed female Sprague Dawley rats to Cannabis smoke daily from gestational day 6 to 20 or room air. Maternal reproductive parameters, offspring behavior, and gene expression in the offspring amygdala were assessed. Body temperature was decreased in dams following smoke exposure and more fecal boli were observed in the chambers before and after smoke exposure in dams exposed to smoke. Maternal weight gain, food intake, gestational length, litter number, and litter weight were not altered by exposure to Cannabis smoke. A significant increase in the male-to-female ratio was noted in the Cannabis -exposed litters. In adulthood, male and female Cannabis smoke-exposed offspring explored the inner zone of an open field significantl...

Most human navigation studies in MRI rely on virtual navigation. However, the necessary supine position in MRI makes it fundamentally different from daily ecological navigation. Nonetheless, until now, no study has assessed whether differences in physical body orientation (BO) affect participants’ experienced BO during virtual navigation. Here, combining an immersive virtual reality navigation task with subjective BO measures and implicit behavioral measures, we demonstrate that physical BO (either standing or supine) modulates experienced BO. Also, we show that standing upright BO is preferred during spatial navigation: participants were more likely to experience a standing BO and were better at spatial navigation when standing upright. Importantly, we report that showing a supine virtual agent reduces the conflict between the preferred BO and physical supine BO. Our study provides critical, but missing, information regarding experienced BO during virtual navigation, which should be considered cautiously ...

Every so often, I conclude that life is not possible. It is not uncommon for me to walk out of a seminar about the pathways and dynamics of biochemical signaling or the structure of biological molecules to conclude that the complexities of life processes defy imagination. Our ability to maintain a sense of wonder about the mysteries of biological mechanisms is what drives us as scientists, as otherwise wresting new insights from the recalcitrant world of interacting pathways would be too frustrating. So all successful biologists must, paradoxically, see both the proverbial forest and their trees, and recognize both the elegant simplicity and the confounds characteristic of living organisms. That sense of mystery and wonder is somewhat at odds with our common sense. It is common sense that is now too often lost, as we grapple with new technologies and large datasets in our science. As scientists, today, we must balance our common sense with our growing reliance on big data to extract the new insights about...

The sensory system allows humans to not only explore the world but also to monitor their own bodies for injury and disease through the sensation of pain. After an injury, signals from the injured tissues travel along the nerves, entering the central nervous system through the spinal cord before going into the brain. In the acute stages, pain modulates behavior in ways that promote healing, including limiting mobility. In most cases, pain resolves as the injury heals, but, in some cases, pain persists and becomes chronic. Chronic pain is a massive issue, affecting up to 20% of Americans and leading to reduced quality of life for those affected. The factors leading to chronic pain are complex, and new approaches are needed to improve understanding of chronic pain and find effective treatments. In the current issue of eNeuro , Haroun et al. (2023) use a new approach to transiently silence sensory neurons in uninjured mice as well as mouse models of acute and chronic pain using a technique known as chemogenet...