Deterioration of Brain Neural Tracts in Elderly Women with Sarcopenia.

OBJECTIVES: Sarcopenia is known to be associated with increased stiffness in brain arteries, which causes deterioration in brain structure and function. In this study, the authors evaluated the deterioration of neural tracts using diffusion tensor tractography (DTT) in elderly women with sarcopenia and investigated whether deterioration of neural tracts is consistent with clinical findings. METHODS: Twenty elderly women with sarcopenia were recruited. Muscle mass was measured by dual energy x-ray absorptiometry. Hand-grip power and gait speed were also assessed. Memory function was evaluated using the Seoul Neuropsychological Screening Battery. Additionally, using DTT-Studio software, the authors evaluated eight neural tracts: the corticospinal tract (CST), corticoreticular pathway, fornix, cingulum, superior longitudinal fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, and optic radiation. The authors measured the DTT parameters (fractional anisotropy [FA] and fiber volume [FV]) for each neural tract. RESULTS: The FA and FV values were decreased in all the evaluated neural tracts, compared with those of the 20 normal comparison subjects. The FVs of the CST were significantly correlated with the hand-grip power of elderly women with sarcopenia. The FVs of the fornix and cingulum in elderly women with sarcopenia were significantly correlated with their memory function. CONCLUSION: The authors found that the neural tracts in elderly women with sarcopenia were extensively deteriorated, and their hand-grip power and memory function were associated with related neural tracts. The DTT seems to be a useful tool for evaluating structural changes in the brains of people with sarcopenia.

Effortful swallowing training coupled with electrical stimulation leads to an increase in hyoid elevation during swallowing.

We tested the effects of surface electrical stimulation on hyoid elevation during swallowing in healthy volunteers. Sixteen people were recruited and randomly divided into two groups. Electrical stimulation was applied to the skin above the infrahyoid muscle in the experimental group. The stimulation current was adjusted until muscle contraction occurred and the hyoid bone became depressed. Participants were asked to swallow forcefully so as to elevate the hyolaryngeal complex when the stimulation began. The same experiment was performed in the control group except the intensity of stimulation was adjusted to just above the sensory threshold. The two groups received ten 20-min treatments over 2 weeks. We recorded the myoelectrical activity of the submental muscles and the amount of hyoid bone movement at three time points (pretreatment, immediately post-treatment, and 2 weeks after treatment). In the experimental group, the amount of y-axis hyoid bone excursion was increased immediately post-treatment, but this effect faded within 2 weeks following the treatment. Myoelectrical activity was not affected by either treatment regimen. We concluded that effortful swallowing coupled with electrical stimulation increases the degree of hyoid elevation in healthy volunteers. It needs to be evaluated for its long-term effectiveness in increasing the elevation of hyolaryngeal complex.