Background and Objectives:Laryngeal dystonia (LD) is isolated task-specific focal dystonia selectively impairing speech production. The first choice of LD treatment is botulinum neurotoxin (BoNT) injections into the affected laryngeal muscles. However, whether BoNT has a lasting therapeutic effect on disorder pathophysiology is unknown. We investigated short- and long-term effects of BoNT treatment on brain function in LD patients.Methods:A total of 161 subjects participated in the functional MRI study. Statistical analyses examined central BoNT effects in LD patients who were stratified based on the effectiveness and duration of treatment.Results:LD patients who were treated and benefited from BoNT injections had reduced activity in the left precuneus compared to BoNT-naïve and treatment non-benefiting patients. Additionally, BoNT-treated patients with adductor LD had decreased activity in the right thalamus, whereas BoNT-treated abductor LD patients had reduced activity in the left inferior frontal cortex. No statistically significant differences in brain activity were found between patients with shorter (1-5 years) and longer (13-28 years) treatment durations. However, patients with intermediate treatment duration of 6 to 12 years showed reduced activity in the right cerebellum compared to patients with both shorter and longer treatment durations and reduced activity in the right prefrontal cortex compared to patients with shorter treatment duration.Discussion:Our findings suggest that the left precuneus is the site of short-term BoNT central action in LD patients, whereas the prefrontal-cerebellar axis is engaged in the BoNT response in patients with intermediate treatment duration of 6-12 years. Involvement of these structures points to indirect action of BoNT treatment on the dystonic sensorimotor network via modulation of speech motor sequence planning and coordination.

Objective: Critical decisions are made by effective teams that are characterized by individuals who trust each other and know how to best integrate their opinions. Here, we introduce a multimodal BCI to help collaborative teams of humans and an artificial agent achieve more accurate decisions in assessing danger zones during a pandemic scenario. Approach: Using high-resolution simultaneous EEG/fMRI, we first disentangled the neural markers of decision-making confidence and trust and then employed machine-learning to decode these neural signatures for BCI-augmented team decision-making. We assessed the benefits of BCI on the team’s decision-making process compared to the performance of teams of different sizes using the standard majority or weighing individual decisions. Main results: We showed that BCI-assisted teams are significantly more accurate in their decisions than traditional teams, as the BCI is capable of capturing distinct neural correlates of confidence on a trial-by-trial basis. Accuracy and subjective confidence in the context of collaborative BCI engaged parallel, spatially distributed, and temporally distinct neural circuits, with the former being focused on incorporating perceptual information processing and the latter involving action planning and executive operations during decision making. Among these, the superior parietal lobule emerged as a pivotal region that flexibly modulated its activity and engaged premotor, prefrontal, visual, and subcortical areas for shared spatial-temporal control of confidence and trust during decision-making. Significance: Multimodal, collaborative BCIs that assist human-artificial agent teams may be utilized in critical settings for augmented and optimized decision-making strategies.

BackgroundEssential tremor of voice (ETv) is characterized by involuntary oscillations of laryngeal and upper airway muscles, causing rhythmic alterations in pitch and loudness during both passive breathing and active laryngeal tasks, such as speaking and singing. Treatment of ETv is challenging and typically less effective compared with treatment of ET affecting extremities.ObjectiveWe conducted a proof‐of‐concept, open‐label phase II study to examine the efficacy and central effects of sodium oxybate in patients with alcohol‐responsive ETv.MethodsAll subjects received 1.0 to 1.5 g of oral sodium oxybate and underwent brain functional magnetic resonance imaging. The primary endpoint was the number of patients (% from total) with reduced ETv symptoms by at least 10% at about 40 to 45 minutes after sodium oxybate intake based on the combined visual analog scale score of ETv symptom severity. The secondary endpoint included changes in brain activity after sodium oxybate intake compared to baseline.ResultsSodium oxybate reduced ETv symptoms on average by 40.8% in 92.9% of patients. Drug effects were observed about 40 to 45 minutes after intake, lasting about 3.5 hours, and gradually wearing off by the end of the fifth hour. The central effects of sodium oxybate were associated with normalized activity in the cerebellum, inferior/superior parietal lobules, inferior frontal gyrus, and insula and re‐established functional relationships between these regions.ConclusionsSodium oxybate showed high efficacy in ETv patients, with a likely central action on disorder pathophysiology. Sodium oxybate may be an effective novel oral drug for treatment of alcohol‐responsive ETv patients. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.