The meaning of spontaneous skin conductance activity, and its relevance to appraisal theory, are examined. Spontaneous skin conductance activity is hypothesised to reflect task engagement, and thus to be correlated with appraisals of problem-focused coping potential. In a within-subjects design, subjects solved anagrams in which task difficulty was manipulated by varying both the difficulty of the anagrams and the amount of time available to solve them. In the most difficult condition, appraisals of coping potential were expected, and observed, to be (...) especially low, and these appraisals were predicted to produce selective disengagement from the task, yielding reduced skin conductance activity. Within trials, skin conductance activity increased at the start of the trials in all conditions, but decreased by the end of the trials in the most difficult condition only. At the end of the trials, both spontaneous response rate and maximum response amplitude were positively correlated, within-subjects, with appraisals of coping potential, and, even after controlling for task difficulty, with solving the anagram. These findings support the hypothesised relation between appraised coping potential and spontaneous skin conductance activity, and the interpretation of this activity as reflecting task engagement. (shrink)