Cortical excitability changes in patients with sleep-wake disturbances after traumatic brain injury
Abstract
Although chronic sleepiness is common after head trauma, the cause remains unclear. Transcranial magnetic stimulation (TMS) represents a useful complementary approach in the study of sleep pathophysiology. We aimed to determine in this study whether post-traumatic sleep-wake disturbances (SWD) are associated with changes in excitability of the cerebral cortex. TMS was performed 3 months after mild to moderate traumatic brain injury (TBI) in 11 patients with subjective excessive daytime sleepiness (EDS; defined by the Epworth Sleepiness Scale ≥10), 12 patients with objective EDS (as defined by mean sleep latency <5 on multiple sleep latency tests), 11 patients with fatigue (defined by daytime tiredness without signs of subjective or objective EDS), 10 patients with post-traumatic hypersomnia "sensu strictu," and 14 control subjects. Measures of cortical excitability included central motor conduction time, resting motor threshold (RMT), short-latency intracortical inhibition (SICI), and intracortical facilitation to paired-TMS. RMT was higher and SICI was more pronounced in the patients with objective EDS than in the control subjects. In the other patients all TMS parameters did not differ significantly from the controls. Similarly to that reported in patients with narcolepsy, the cortical hypoexcitability may reflect the deficiency of the excitatory hypocretin/orexin-neurotransmitter system. These observations may provide new insights into the causes of chronic sleepiness in…
How strong is the evidence?
Evidence Hub reads this as a case-control, done in people. Its evidence level is 4 of 5 (Low · observational). Observational designs can show an association but not prove cause. Reported size: 14 participants or records.
Read the paper
Related studies
- The Matrisome: In Silico Definition and In Vivo Characterization by Proteomics of Normal and Tumor Extracellular Matrices
- The Escherichia coli MG1655 in silico metabolic genotype: Its definition, characteristics, and capabilities
- In silico pharmacology for drug discovery: methods for virtual ligand screening and profiling
- In silico prediction of splice-altering single nucleotide variants in the human genome
- In silico clinical trials: how computer simulation will transform the biomedical industry
- In silico optimization of a guava antimicrobial peptide enables combinatorial exploration for peptide design
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.