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Background: Evidence suggests that neurometabolic abnormalities can persist after traumatic brain injury (TBI) and drive clinical symptoms such as fatigue and cognitive disruption. Magnetic resonance spectroscopy has been used to investigate metabolite abnormalities following TBI, but few studies have obtained data beyond the subacute stage or over large brain regions., Objective: To measure whole-brain metabolites in chronic stages of TBI., Design: Observational study., Setting: University., Participants: Eleven men with a moderate or severe TBI more than 12 months prior and 10 age-matched healthy controls completed whole-brain spectroscopic imaging., Main Measures: Ratios of N-acetylaspartate (NAA), choline (CHO), and myo-inositol (MI) to creatine (CR) were measured in whole-brain gray and white matter as well as 64 brain regions of interest. Arterial spin labeling (ASL) data were also collected to investigate whether metabolite abnormalities were accompanied by differences in cerebral perfusion., Results: There were no differences in metabolite ratios within whole-brain gray and white matter regions of interest (ROIs). Linear regression showed lower NAA/CR in the white matter of the left occipital lobe but higher NAA/CR in the gray matter of the left parietal lobe. Metabolite abnormalities were observed in several brain regions in the TBI group including the corpus callosum, putamen, and posterior cingulate. However, none of the findings survived correction for multiple comparison. There were no differences in cerebral blood flow between patients and controls., Conclusion: Higher MI/CR may indicate ongoing gliosis, and it has been suggested that low CHO/CR at chronic time points may indicate cell death or lack of healthy turnover and repair. However, with the small sample size of this study, we caution against the over interpretation of our results. None of the findings within ROIs survived correction for multiple comparison. Thus, they may be considered possible avenues for future research in this area., (© 2021 American Academy of Physical Medicine and Rehabilitation.)

The relationship between hypnotizability and somatic illness was measured in 45 college students. Several weeks after completing the Waterloo-Stanford Group C Scale (WSGC), participants filled out a somatic-complaint checklist and measures of psychopathology. Results indicated a positive correlation between hypnotizability and somatic illness, and the relationship was stronger for female participants. In contrast to the quadratic model proposed by Wickramasekera, the current data demonstrated a linear relationship between hypnotizability and somatic complaint. Further analyses showed that somatic complaints were associated with hallucination and imagery items, corresponding to the perceptual-cognitive factor identified in Woody, Barnier, and McConkey's (2005) factor analysis of the Stanford Hypnotic Susceptibility Scale, Form C. The results call into question some claims that high hypnotizability is an adaptive and healthy trait.

The present study closely examines subject response to the arm-rigidity item of the HGSHS:A. Subject behavior, subject self-report, and surface EMG of the biceps and triceps muscles were monitored. Two distinct ways of passing the item were observed and verified by EMG recordings: some subjects (tremblers) exerted muscular effort to bend the arm and kept it rigidly straight. Others (nontremblers) passively kept the arm straight without exerting muscular effort to bend, even though they reported exerting effort to bend their arm. These two behaviorally and physiologically different methods of passing the item support the idea of individual differences in hypnotic responding and suggest that subjects may be using different mental processes to pass the item.