Increase In Skin Conductance Level Research Articles

Anxiety and the habituation of the skin conductance response.

ABSTRACTThe effect of threat of shock on the habituation of the skin conductance response (SCR) to a series of auditory stimuli was assessed. Skin resistance and heart rate were recorded during the presentation of 20, 1 sec, 1000 Hz tones in a control session and in a session at the end of which subjects were led to expect a painful electric shock. The effects of the threat of shock consisted of recovery of the SCR and an increase in skin conductance level and heart rate. They were restricted to the period during which subjects believed the shock to be imminent.Two possible reasons for the SCR recovery were offered, one in terms of Lader and Mathews' (1968) ‘maximal habituation’ hypothesis and a second in terms of a change in the stimulus complex.

Models of mania: An individual case study.

SummaryA longitudinal study of a single case of manic-depressive psychosis investigated the relationship between psychiatric ratings, reaction time and two measures of autonomic activity. Measurements were made on 19 occasions over a five-month period. The number of slow responses on the reaction time task increased with increasing depression. Manic periods appeared not to be characterized by a slowing of responses, but rather by an increase in the number of premature responses, i.e. those made to the warning signal. A derived performance index discriminated over the complete range from severe depression to severe mania.Increased depression was associated with lower heart rate resting levels, and increasing mania with increased skin conductance levels. An increased frequency of slow reaction times was significantly associated with lower resting heart rate. Skin conductance measures correlated significantly with the number of premature responses made on the reaction time tasks. Some differences in the relationships emerged when data obtained during the administration of lithium were included in the analysis.The results are discussed in relation to both the bipolar and the continuum models of manic-depressive psychosis. The latter model is not supported by the present investigation, since manic episodes were not characterized by a more severe departure from normality than depressive episodes on either the number of slowed responses or autonomic measures.

Cardiovascular variables, skin conductance and time estimation: changes after the administration of small doses of nicotine.

Three tobacco cigarettes with known content of nicotine and one lettuce-leaf cigarette were smoked by 24 young habitual smokers, at different times of day and fixed rates of smoking. Changes in various psychophysiological parameters were automatically recorded during the 60 min which followed smoking. Heart rate and forearm blood flow increases were found to be dose dependent, the latter occurring only after smoking at the fast rate and their duration simultaneous to the presence of active nicotine in the organism. Skin vasoconstriction, as measured by decreases in temperature showed itself more reactive to environmental stimuli than to drug effects. Significant increases in skin conductance levels lasting throughout the experimental session occurred immediately after smoking, although not related to drug effects. Diphasic effects of nicotine were, however, obtained with the two largest doses, at different times of day. This finding is discussed in relation to possible “unspecific” nicotine effects upon a preexisting level of “activation”. Nicotine did not influence subjective time estimates. However, a specific pattern of responses occurred. This is discussed in terms of “disruption” of the timing task and a gradual re-organization towards pre-smoking estimates. The value of psychophysiological indices in relation to drugs of habitual use is questioned.