Exteroceptive suppression of temporalis and masseter muscle activity is enhanced in offspring of hypertensives.

Exteroceptive suppression of temporalis and masseter muscle activity was examined in young men with and without a parental history of hypertension. Recent clinical studies suggest that the second exteroceptive suppression period is attenuated in several chronic pain disorders and that this brainstem reflex may serve as a noninvasive index of endogenous pain control. In the present study, offspring of hypertensives exhibited a significant protraction of the late exteroceptive suppression period for both muscle sites, suggesting that the decreased pain sensitivity previously observed in individuals at risk for hypertension may be related to enhanced central pain modulation.

Predicting vasovagal reactions in volunteer blood donors.

Measures of blood and injury sensitivity, pain sensitivity, and anxiety were examined as potential predictors of syncope and related reactions in 215 volunteer blood donors. The Blood and Injury Fears subscale of the Fear Survey Schedule was the best predictor for first-time donors (r[84] = 0.43, p < 0.001), whereas the Mutilation Questionnaire was the best predictor for experienced donors (r[127] = 0.31, p < 0.01). In contrast with previous studies, few significant predictions were observed for demographic variables (e.g., age, body mass index, or number of previous donations), suggesting that psychological measures may be better suited to the task of identifying high risk donors.