International journal of psychophysiology : official journal of the International Organization of Psychophysiology
-
Int J Psychophysiol · Oct 2009
Influence of blood pressure elevations by isometric exercise on pain perception in women.
Very little research has been conducted examining the relationship between blood pressure (BP), exercise, and hypoalgesia especially in women, even though research indicates that there is an interaction between pain modulatory and cardiovascular systems. The purpose of this study was to examine if pain perception was altered shortly after brief isometric contractions that caused an associated transient prior elevation in BP. Twenty-three healthy women completed two randomly-assigned sessions consisting of isometric exercise (25% MVC for 1-min and 3-min) and quiet rest. ⋯ Patterns of responses for PT, however, differed with a small increase in PT following 3-min vs 1-min of isometric exercise (d=0.38) while there was a small decrease in PT following 3-min vs 1-min of quiet rest (d=0.20). PR-I and PR-U were not found to change significantly following isometric exercise or quiet rest. It was concluded that both durations of isometric exercise significantly elevated BP, but these elevations in BP were not associated with a consistent alteration in pain perception in this sample of normotensive women.
-
Int J Psychophysiol · Sep 2009
An ERP study on the time course of phonological and semantic activation in Chinese word recognition.
With the event-related potential (ERP) technique, we examined the time course of phonological and semantic activation in Chinese word recognition. Participants did a semantic judgment task and a homophone judgment task over the same set of word pairs. Each pair was of either high or low word frequency and the two words were either unrelated or related semantically or phonologically, i.e., being homophones. ⋯ For low-frequency words, the semantically related pairs in the homophone task were associated with a similar modulation of N400. However, compared to the unrelated controls, the homophonic pairs in the semantic task elicited a larger P200, a component implicated in phonological processing in the literature, and thus demonstrated a phonological activation earlier than semantic activation. The results showed that word frequency affects the time course of semantic and phonological activation suggesting that phonology is not invariably activated before semantics in Chinese word recognition.
-
Int J Psychophysiol · May 2009
Habitual traffic noise at home reduces cardiac parasympathetic tone during sleep.
The relationships between road and rail traffic noise with pre-ejection period (PEP) and with respiratory sinus arrhythmia (RSA) during sleep, as indices of cardiac sympathetic and parasympathetic nervous system tone, were investigated in the field (36 subjects, with 188 and 192 valid subject nights for PEP and RSA, respectively). Two analyses were conducted. The first analysis investigated the overall relationships across the entire sleep period. ⋯ No significant relationships were observed for PEP. The results indicate that higher indoor traffic noise exposure levels may lead to cardiac parasympathetic withdrawal during sleep, specifically during the second half of the sleep period. No effect of indoor traffic noise on cardiac sympathetic tone was observed.
-
Int J Psychophysiol · Mar 2009
Emotional modulation of autonomic responses to painful trigeminal stimulation.
Dysregulation of supraspinal pain modulation may contribute to chronic pain, including head/face pain. Our laboratory has shown that emotional picture-viewing reliably modulates subjective and physiological pain responses to noxious extracranial (sural nerve) stimulation, suggesting this is a valid method of studying supraspinal modulation. However, to study head/face pain, it is important to determine whether responses evoked by trigeminal stimulation are also modulated. ⋯ Autonomic responses to each shock (pain-evoked HR acceleration, pain-evoked skin conductance response [SCR]) were recorded. Consistent with research on extracranial pain, autonomic responses were larger during unpleasant pictures and smaller during pleasant pictures, with linear trends explaining 23% of the variance in pain-evoked HR and 35% of the variance in pain-evoked SCR (ps<.05). Implications for studying cranial pain are discussed.
-
Int J Psychophysiol · Feb 2009
Randomized Controlled Trial Clinical TrialEnd-tidal versus transcutaneous measurement of PCO2 during voluntary hypo- and hyperventilation.
Recent studies have shown that end-tidal PCO(2) is lower during anxiety and stress, and that changing PCO(2) by altering breathing is therapeutic in panic disorder. However, end-tidal estimation of arterial PCO(2) has drawbacks that might be avoided by the transcutaneous measurement method. Here we compare transcutaneous and end-tidal PCO(2) under different breathing conditions in order to evaluate these methods in terms of their comparability and usability. ⋯ The results show that PCO(2) estimated by the two methods was comparable except that for transcutaneous measurement registration of changes in PCO(2) was delayed and absolute levels were much higher. Both methods documented that paused breathing was effective for raising PCO(2), a presumed antidote for anxious hyperventilation. We conclude that since the two methods give comparable results choosing between them for specific applications is principally a matter of whether the time lag of the transcutaneous method is acceptable.