Electrophysiological evidence of functional integration between the language and motor systems in the brain: a study of the speech Bereitschaftspotential.

OBJECTIVE: We investigated whether the Bereitschaftspotential (BP), an event related potential believed to reflect motor planning, would be modulated by language-related parameters prior to speech. We anticipated that articulatory complexity would produce effects on the BP distribution similar to those demonstrated for complex limb movements. We also hypothesized that lexical semantic operations would independently impact the BP. METHODS: Eighteen participants performed 3 speech tasks designed to differentiate lexical semantic and articulatory contributions to the BP. EEG epochs were time-locked to the earliest source of speech movement per trial. Lip movements were assessed using EMG recordings. Doppler imaging was used to determine the onset of tongue movement during speech, providing a means of identification and elimination of potential artifact. RESULTS: Compared to simple repetition, complex articulations produced an anterior shift in the maximum midline BP. Tasks requiring lexical search and selection augmented these effects and independently elicited a left lateralized asymmetry in the frontal distribution. CONCLUSIONS: The findings indicate that the BP is significantly modulated by linguistic processing, suggesting that the premotor system might play a role in lexical access. SIGNIFICANCE: These novel findings support the notion that the motor systems may play a significant role in the formulation of language.

Enhanced endothelium-dependent vasodilation in Fabry disease.

BACKGROUND AND PURPOSE: Fabry disease is an X-linked lysosomal storage disease secondary to deficiency of alpha-galactosidase A with resulting glycolipid accumulation, particularly globotriaosylceramide in arterial smooth muscle and endothelial cells. A systemic vasculopathy, including early-onset stroke, is prevalent without a clear pathogenesis. METHODS: Seventeen normotensive and normocholesterolemic hemizygous Fabry patients (aged 21 to 49 years) and 13 control subjects (aged 21 to 48 years) were investigated by venous plethysmography, allowing assessment of forearm blood flow. Plethysmographic measurements were obtained at baseline and during intra-arterial infusion of acetylcholine and sodium nitroprusside both with and without N(G)-monomethyl-L-arginine (L-NMMA). RESULTS: Forearm blood flow was significantly higher in patients than in control subjects at all 3 acetylcholine doses (P=0.014). Patients had a greater response to acetylcholine even after the addition of L-NMMA (P=0.036). CONCLUSIONS: These results demonstrate an increased endothelium-mediated vascular reactivity in Fabry disease. The increased vessel response to acetylcholine with and without L-NMMA suggests altered functionality of non-NO endothelium-dependent vasodilatory pathways.

The effects of stray voltage on turkey poults.

Three successive flocks of turkey poults experienced cumulative mortality of 10% to 26% through the fifth week of brooding. Stray electrical voltage was suspected after no definitive laboratory diagnosis could be made and no evidence of management deficiency was found. Alternating current voltages of 0.2 to 2.5 volts were detected between waterers and the floor and between the water line and gas line. When the water line was equipment-grounded to the electrical service entrance, the subsequent flock had no mortality problem. A series of experiments was conducted to determine the sensitivity of turkey poults to alternating current. Based on these experiments, the voltage levels measured at the farm probably did not cause the mortality experienced in the three flocks. The reason for the farm problem could have been 1) the poults experienced higher voltage than was present when measurements were taken, 2) the voltage may have been intermittent, or 3) there was a difference between the farm environment and the cage battery environment in the experiments.

A comparison of two HRAs for use in the university classroom.

Current interest in health and wellness combined with the proliferation of Health Risk Appraisals (HRAs) has made classroom use of such instruments increase rapidly in recent years. This study compared two HRAs in terms of appraised age, attainable age, the list of positive lifestyle factors for reinforcement, the list of lifestyle factors to be changed, and the variables of desirable weight and blood pressure as well as observed differences in display and unique comment characteristics. One hundred and thirty-three students at a large southeastern university comprised the sample. Though no significant differences were found in appraised age or attainable age, significant differences existed in the number of positive lifestyle changes listed, number of suggested lifestyle changes to be made by students, and several observable differences in display including graphics and tables. Implications for health educators are noted.