Dravet syndrome is a severe, childhood-onset epilepsy largely due to heterozygous loss-of-function mutation of the gene , which encodes the type 1 neuronal voltage-gated sodium (Na) channel α subunit Nav1.1. Prior studies in mouse models of Dravet syndrome ( mice) indicate that, in cerebral cortex, Nav1.1 is predominantly expressed in GABAergic interneurons, in particular in parvalbumin-positive fast-spiking basket cell interneurons (PVINs). This has led to a model of Dravet syndrome pathogenesis in which Nav1.1 mutation leads to preferential dysfunction of interneurons, decreased synaptic inhibition, hyperexcitability, and epilepsy. However, such studies have been implemented at early developmental time points. Here, we performed electrophysiological recordings in acute brain slices prepared from male and female mice as well as age-matched wild-type littermate controls and found that, later in development, the excitability of PVINs had normalized. Analysis of action potential waveforms indirectly suggests a reorganization of axonal Na channels in PVINs from mice, a finding supported by immunohistochemical data showing elongation of the axon initial segment. Our results imply that transient impairment of action potential generation by PVINs may contribute to the initial appearance of epilepsy, but is not the mechanism of ongoing, chronic epilepsy in Dravet syndrome. Dravet syndrome is characterized by normal early development, temperature-sensitive seizures in infancy, progression to treatment-resistant epilepsy, developmental delay, autism, and sudden unexplained death due to mutation in encoding the Na+ channel subunit Nav1.1. Prior work has revealed a preferential impact of Nav1.1 loss on the function of GABAergic inhibitory interneurons. However, such data derive exclusively from recordings of neurons in young mice. Here, we show that impaired action potential generation observed in parvalbumin-positive fast-spiking interneurons (PVINs) in+/- mice during early development has normalized by postnatal day 35. This work suggests that a transient impairment of PVINs contributes to epilepsy onset, but is not the mechanism of ongoing, chronic epilepsy in Dravet syndrome.

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Severe and enduring eating disorders (EDs) have the highest mortality rate of all psychiatric illnesses (Arch Gen Psychiatry, 2011, 68, 724), especially when comorbid with treatment‐resistant depression (TRD) (Psychiatr Res, 2016, 244, 45). We report on four patients with enduring EDs and TRD treated with repeat ketamine over 12 + months, showing improvement in depression with only modest changes in ED symptoms.

Sensorimotor rhythm (SMR)-based brain–computer interfaces (BCIs) provide an alternative pathway for users to perform motor control using motor imagery. Despite the non-invasiveness, ease of use, and low cost, this kind of BCI has limitations due to long training times and BCI inefficiency—that is, the SMR BCI control paradigm may not work well on a subpopulation of users. Meditation is a mental training method to improve mindfulness and awareness and is reported to have positive effects on one’s mental state. Here, we investigated the behavioral and electrophysiological differences between experienced meditators and meditation naïve subjects in one-dimensional (1D) and two-dimensional (2D) cursor control tasks. We found numerical evidence that meditators outperformed control subjects in both tasks (1D and 2D), and there were fewer BCI inefficient subjects in the meditator group. Finally, we also explored the neurophysiological difference between the two groups and showed that the meditators had a higher resting SMR predictor, more stable resting mu rhythm, and a larger control signal contrast than controls during the task.

Sensorimotor rhythm (SMR) based brain-computer interfaces (BCIs) provide an alternative pathway for users to perform motor control using motor imagery (MI). Despite the non-invasiveness, ease of use and low cost, this kind of BCI has limitation due to long training times and BCI inefficiency— where a subpopulation cannot generate decodable EEG signals to perform the control task. Meditation is a mental training method to improve mindfulness and awareness, and is reported to have a positive effect on one’s mental state. Here we investigate the behavioral and electrophysiological differences between experienced meditators and meditation naïve subjects in 1-dimensional and 2-dimensional cursor control tasks. We found that within subjects who have room for improvement, meditators outperformed control subjects in both tasks, and there were fewer BCI insufficient subjects in the meditator group. Finally, we also explored the neurophysiological difference between the two groups, and showed that meditators had higher SMR predictor and were better able to generate decodable EEG signals to achieve SMR BCI control.