Biomedical subjects

J Naveteur

Publications and source records attributed to J Naveteur.

6 recordsLinked to original sources

PubMed1999

Diurnal variations of tonic electrodermal activity.

Diurnal variability of skin conductance level (SCL) was examined in two complementary experiments, simultaneously with variability of skin temperature (ST) and that of simple reaction time (RT) which was recorded as a behavioural index of arousal. In Experiment I, 6 subjects spent 6 days in the laboratory in homogeneous conditions. Three recording sessions, each lasting 2 h, began, respectively, at 9:00 a.m. (morning), 1:00 p.m. (afternoon) and 5:00 p.m. (evening). Results indicated that SCL increased linearly throughout the day. Experiment II was undertaken to test whether this effect could still be observed in more heterogeneous conditions. Subjects (n = 12) attended to their own activities between the two 30-min sessions beginning, respectively, at 9:30 a.m. and 6:00 p.m. during a single experimental day. Again, SCL was higher in the evening than in the morning. In both experiments the SCL pattern seemed to be asynchronous with ST and RT variations. Taken as a whole, these data bring additional evidence of temporal electrodermal variation, a phenomenon which should be further taken into account in EDA research.

Adult↗

PubMed1998

Electrodermal level asymmetry in a unilateral brain-damaged patient.

The purpose of this article is to report on a patient with right frontal damage who exhibited a strong left > right asymmetry of skin conductance levels (SCLs). Comparison with a control group indicates that this asymmetry resulted only from a higher SCL on the left hand. Such a result suggests that the frontal lesion has induced a contralateral disinhibition and is consistent with the idea of a contralateral inhibitory control of tonic electrodermal activity in the case of a healthy hemisphere. Peripheral factors, such as sweating or temperature seem unrelated to the SCL asymmetry and a possible influence of motor weakness is also rejected following comparison with a second patient who presented the same motor disorder without atypical SCL asymmetry. In contrast to SCLs, no asymmetry in skin conductance response amplitudes was observed in the former patient. This discrepancy is in line with previous observations showing that tonic and phasic EDA could depend on different neurophysiological controls.

Brain Damage, Chronic↗

PubMed1995

Cutaneous thresholds and anxiety: influence of eye orientation and lateral asymmetry.

This study investigated the combined influence of anxiety and eye orientation on cutaneous thresholds. The relationship between anxiety and the lateral differences was also examined. Right-handed subjects of low and high trait anxiety received weak electric shocks on either hand. Cutaneous thresholds were recorded when eyes were directed towards or away from the stimulated area. State anxiety was retrospectively assessed. As compared to a contralateral eye orientation, directing the eyes ipsilaterally to the stimulated area yielded lower thresholds for subjects low in trait anxiety. This effect was not observed for subjects high in trait anxiety. The benefit of the ipsilateral orientation was higher for subjects with lower state-anxiety scores as well. Besides, subjects low in trait anxiety presented a left-hand advantage which was not shown by those high in trait anxiety. The left-right difference in thresholds was also positively correlated with state anxiety. The eye-orientation results are discussed in terms of anxiety-induced modification of spatial attention and the differential hand sensitivity findings in terms of hemispheric specialization.

Adolescent↗

PubMed1992

Anxiety, emotion and cerebral blood flow.

Regional cerebral blood flow was measured by the xenon inhalation technique using a DSPECT system, during neutral and emotional auditory stimulations. Subjects were 10 high and 10 low trait anxiety, right-handed females. State anxiety was retrospectively assessed. Results indicated a lower rCBF in the high trait or state anxiety subjects who presented also a global rCBF asymmetry in the right > left direction. Additionally, the emotional content of the stimuli interacted significantly with the side of the brain in the thalamic area.

Adult↗

PubMed1991

Reliability of bilateral differences in electrodermal activity.

To evaluate the reliability of electrodermal lateralization, skin conductance response (SCR) and skin potential response (SPR) amplitudes were recorded bilaterally in 11 right-handed male students during 4 identical experimental sessions each a week apart. After a rest period of 5 min, a set of auditory stimuli (1000 Hz, 100 dB, 1 s) was delivered. Results of both recordings showed a significant lateralization for all sets of response in the majority of subjects, but the reliability of the right-left (R-L) differences was low from one session to another. However, results suggest the existence of different degrees in stability according to subjects. Otherwise, the R-L differences appear to be recording technique dependent. These results have implications for the influence of central and peripheral factors on electrodermal activity laterality.

Adult↗

PubMed1988

Electrodermal asymmetry and vigilance in negative emotion, anxiety and stress.

Bilateral electrodermal levels and responses were recorded during an emotional and neutral slide projection in high and low trait anxiety subjects. Half of the subjects of each group received reassuring instructions the other half received stressful instructions. Levels were more symmetrical in anxious subjects but asymmetry was not influenced by instruction type. In contrast, responses were more symmetrical in anxious subjects, were more symmetrical under stressful instructions but were more asymmetrical to the emotional than the neutral slides.

Adolescent↗