Reported fatigue, difficulty, and cardiovascular response to an auditory mental arithmetic challenge.

Undergraduates scoring low and high on a questionnaire measure of relatively extended fatigue were presented four versions of an auditory mental arithmetic challenge, ranging in difficulty from low to impossibly high. Among Low Fatigue participants, blood pressure and heart rate responses assessed during the work periods first rose and then fell with difficulty. Among High Fatigue participants, blood pressure responses remained low across difficulty conditions, while heart rate responses rose weakly from the low- to the moderate difficulty condition and then declined. Findings are discussed in terms of a recent interactional analysis of fatigue influence on cardiovascular response.