Biomedical subjects

Olav Vassend

Publications and source records attributed to Olav Vassend.

5 recordsLinked to original sources

PubMed2005

Characterizing individual differences in heat-pain sensitivity.

Heat induced pain has been shown to follow a positively accelerating power function for groups of subjects, yet the extent to which this applies to individual subjects is unknown. Statistical methods were developed for assessing the goodness of fit and reliability of the power function for data from individual subjects with the aim of using such functions for characterizing individual differences in heat-pain sensitivity. 175 subjects rated ascending and random series of contact heat stimuli with visual analogue scales for pain intensity (VAS-I) and unpleasantness (VAS-A). Curve fitting showed excellent model fit. Substitution of model estimates in place of observed VAS scores produced minimal bias in group means, about 0.3 VAS units in the ascending series and 1.0 in the random series, on a 0-100 scale. Individual power function exponents were considerably higher for the ascending than for the random series and somewhat higher for VAS-A than for VAS-I (means: ascending VAS-I=9.04, VAS-A=9.80; random VAS-I=4.95, VAS-A=5.67). The reliability of VAS estimates was high (>==.93), and for the ascending series it remained so when extrapolating 4 degrees C beyond the empirical range. Exponent reliability was high for the ascending series (VAS-I=.92; VAS-A=.91), but considerably lower for the random series (VAS-I=.69; VAS-A=.71). Individual differences constituted 60% of the total variance in pain ratings, whereas stimulus temperature accounted for only 40%. This finding underscores the importance of taking individual differences into account when performing pain studies.

Adult↗

PubMed2005

Effects of repeated electrocutaneous pain stimulation on facial blood flow.

The purpose of the study was to examine the effects of repeated electrocutaneous pain stimulation of the hand on facial blood flow responses in healthy human subjects (58 adult women). Finger blood flow, mean arterial blood pressure, and heart rate were also monitored. To investigate the influence of psychological factors, the subjects' affect states were assessed, and physiological responding was explored during cognitive distraction, i.e., when attention was turned away from the unpleasant stimulus. Consistently, electrocutaneous stimulation elicited vasodilatation in the cheek, together with finger vasoconstriction. This response pattern was evident even at non-painful stimulation intensities. The facial blood flow response showed habituation across stimulation trials and was largely unrelated to systemic cardiovascular changes, affect states, and attentional manipulation. These findings indicate (1) that the experimentally induced facial blood flow changes are part of a non-specific physiological response pattern elicited during noxious stimulation, and (2) that they are not dependent on regional (orofacial) stimulation for their occurrence.

Adult↗

PubMed2005

Personality, affective response, and facial blood flow during brief cognitive tasks.

Blood pressure, heart rate, and changes in facial and finger blood flow were monitored in 58 women during three laboratory tasks, i.e., reading out a neutral text, a personally relevant speech (including a silent preparation phase), and a tracking task. Participants rated the tasks as mild to moderate with regard to affect intensity. Significant effects of personality on affect states were demonstrated, indicating higher levels of anxiety, depression, and anger in the high-neuroticism group, and more curiosity in the high-extraversion group. Arterial pressure, heart rate, and facial blood flow increased during task performance in all three conditions. No relationship between facial blood flow changes and muscle activity measured by m. masseter electromyography (EMG) were demonstrated. Digital vasoconstriction occurred in parallel with facial vasodilatation during tracking and in the preparation phase before the speech. There were no moderator effects of neuroticism or extraversion on blood flow or other cardiovascular responses.

Adult↗

PubMed2004

Cardiovascular responsiveness to brief cognitive challenges and pain sensitivity in women.

The primary purpose of the study was to determine the relationship between cardiovascular (CV) responsiveness to brief cognitive tasks and pain sensitivity in normotensive individuals. Fifty-eight healthy women without a history of chronic pain were exposed to three laboratory tasks (reading aloud, speech task, and tracking task) and repeated pain testing (electrocutaneous and pressure pain stimulation) while mean arterial pressure (MAP) and heart rate (HR) were continuously recorded. Generally, subjects with higher HR responsiveness to the cognitive tasks displayed a reduced pain sensitivity, particularly to electrocutaneous pain stimulation. Moreover, the two types of pain stimulation seemed to trigger somewhat different CV response patterns. Inclusion of pain-related CV changes as control variables affected the relationship between HR responsiveness and pain sensitivity, although differently for electrocutaneous and pressure pain. However, inclusion of psychological control variables had no significant effects. Although relatively large CV changes were observed during the experimental tasks, small and insignificant changes in simultaneous or subsequent electrocutaneous pain sensitivity occurred. However, significant increases in pressure pain threshold and tolerance occurred after the speech task, during which MAP level was at its highest. The present findings support the hypothesis that pain sensitivity and CV response share a common mechanism, which, however, is not necessarily linked to either elevated blood pressure levels or other risk factors for hypertension.

Adaptation, Psychological↗

PubMed2003

Effects of cognitive therapy, applied relaxation and nitrous oxide sedation. A five-year follow-up study of patients treated for dental fear.

Five years after completing a controlled, randomized treatment trial comparing the effect of nitrous oxide sedation (NO), cognitive therapy (CT), and applied relaxation (AR), all 62 patients who had participated were invited to a follow-up questionnaire study. Forty-three responded. All participants had been to the dentist during the follow-up period. Mean scores (s) on Corah's Dental Anxiety Scale (CDAS) and Symptom Checklist 90 Revised (SCL-90-R, a measure of general psychological distress) were 10.4 (4.1) and 0.35 (0.34), respectively. There were no between-group effects. Significant changes across the assessment phases (at enrollment, after treatment, and 5 years after) were found for both dental fear and general distress (CDAS: F = 137.8, P < 0.01; SCL-90-R: F = 12.5, P < 0.01). However, no significant changes between measures obtained after treatment and at follow-up emerged. Seven participants (3 from the NO group, 2 from the CT group, and 2 from the AR group) had CDAS scores above 14, indicating a recurrent or continual dental fear problem. The majority (81%) assessed the dental fear treatment received 5 years previously to have been useful for them. In conclusion, the favorable effects on dental fear and general psychological distress continued at 5-year follow-up for all treatment groups.

Adolescent↗