EEG Correlates of Active Stopping and Preparation for Stopping in Chronic Tic Disorder

The Pathophysiology of Tics: An Anatomic Review

The underlying pathophysiology of tics in Tourette syndrome is a topic of major scientific interest. To date, there is an absence of consensus among researchers regarding the precise anatomic location responsible for tics. The goal of this article is to review the current understanding of these brain circuits and data supporting specific anatomic regions. In summary, current scientific evidence supports the likelihood of multiple areas of abnormality within cortico-basal ganglia-thalamocortical (CBGTC) circuitry or their connected brain regions. A reasonable anatomic hypothesis is that a disruption anywhere within specific circuitry can ultimately lead to the development of a tic disorder.

Emerging Subspecialties: Pediatric Movement Disorders Neurology

Pediatric movement disorders (PMD) neurologists care for infants, children, and adolescents with conditions that disrupt typical movement; serving as important subspecialist child neurologists in both academic and private practice settings. In contrast to adult movement disorders neurologists whose "bread and butter" is hypokinetic Parkinson disease, PMD subspecialty practice is often dominated by hyperkinetic movement disorders including tics, dystonia, chorea, tremor, and myoclonus. PMD neurology practice intersects with a variety of subspecialties, including neonatology, developmental pediatrics, rehabilitation medicine, epilepsy, child & adolescent psychiatry, psychology, orthopedics, genetics & metabolism, and neurosurgery. Over the past several decades, significant advancements in the PMD field have included operationalizing definitions for distinct movement disorders, recognizing the spectrum of clinical phenotypes, expanding research on genetic and neuroimmunologic causes of movement disorders, and advancing available treatments. Subspecialty training in PMD provides trainees with advanced clinical, diagnostic, procedural, and management skills that reflect the complexities of contemporary practice. The child neurologist who is fascinated by the intricacies of child motor development, appreciates the power of observation skills coupled with a thoughtful physical examination, and is excited by the challenge of the unknown may be well-suited to a career as a PMD specialist.

Tourette syndrome research highlights from 2022

This is the ninth yearly article in the Tourette Syndrome Research Highlights series, summarizing selected research reports from 2022 relevant to Tourette syndrome. The authors briefly summarize reports they consider most important or interesting.

Tourette syndrome research highlights from 2022

This is the ninth yearly article in the Tourette Syndrome Research Highlights series, summarizing selected research reports from 2022 relevant to Tourette syndrome. The authors briefly summarize reports they consider most important or interesting.

Neocortical localization and thalamocortical modulation of neuronal hyperexcitability contribute to Fragile X Syndrome

Fragile X Syndrome (FXS) is a monogenetic form of intellectual disability and autism in which well-established knockout (KO) animal models point to neuronal hyperexcitability and abnormal gamma-frequency physiology as a basis for key disorder features. Translating these findings into patients may identify tractable treatment targets. Using source modeling of resting-state electroencephalography data, we report findings in FXS, including 1) increases in localized gamma activity, 2) pervasive changes of theta/alpha activity, indicative of disrupted thalamocortical modulation coupled with elevated gamma power, 3) stepwise moderation of low and high-frequency abnormalities based on female sex, and 4) relationship of this physiology to intellectual disability and neuropsychiatric symptoms. Our observations extend findings in Fmr1-/- KO mice to patients with FXS and raise a key role for disrupted thalamocortical modulation in local hyperexcitability. This systems-level mechanism has received limited preclinical attention but has implications for understanding fundamental disease mechanisms.