Psychophysiological reactivity and the prediction of cardiovascular disorders

Abstract

Two aspects of psychophysiological reactivity that might be relevant to subsequent cardiovascular morbidity were explored in this study. Thirty-six volunteers participated in a single experimental session, during which three taxing cognitive tasks were performed. Interbeat interval, pulse transit time, and respiratory and electrodermal variables were monitored throughout. Large differences between individuals in psychophysiological reactions to the tasks were recorded, and two forms of analysis were therefore performed. Firstly, there is evidence that people exhibiting Type A coronary-prone behaviour pattern show heightened cardiovascular reactions to challenging tasks, and this was tested by administering a student version of the Jenkins Activity Survey. However, high scores on the questionnaire were not associated with interbeat interval or transit time hyper-reactivity. Amongst male subjects the reverse trend was found, since those with scores at the Type B end of the scale produced greater cardiovascular reactions. The second analysis examined the relationship between cardiovascular and other psychophysiological reactions. Cardiovascular responses tended to be coordinated, so that subjects displaying large tachycardias also produced substantial modifications in transit time. Furthermore, haemodynamic hyper-reactivity was not reflected in generalised autonomic lability, since reactive individuals did not show exaggerated responses in electrodermal or respiratory variables. Thus people exhibiting large transit time and heart rate modifications may have specific disturbances in cardiovascular stability, putting them at risk for later haemodynamic disorder.