The effects of experimenter characteristics and two stressors on the hemodynamic responsivity of young normotensive adults

Date of Award




Degree Name

Doctor of Philosophy (Ph.D.)



First Committee Member

Patrice G. Saab, Committee Chair


Cardiovascular reactivity paradigms are used to examine race and gender differences in cardiovascular regulation. The purposes of the present study were to determine if: (1) race and gender differences in responsivity to laboratory challenge emerge; (2) different hemodynamic patterns underlie the hypothesized group differences in responsivity; and (3) differences in experimenter race and gender influence responsivity. Using impedance cardiography, responsivity to the evaluative speech stressor and the foot cold pressor was examined in 81 black subjects (40 men and 41 women) and 86 white subjects (44 men and 42 women). Black men and women and white men and women served as experimenters.The cold pressor elicited greater increases in total peripheral resistance and heart rate and a greater decline in stroke volume from black subjects. White subjects displayed the largest blood pressures and shortest pre-ejection period in response to the speech stressor. Both stressors elicited greater heart rate responses from women. Men demonstrated enhanced blood pressure responses to the cold pressor. Despite the observed differences in responsivity, the response patterns among the groups were similar. Significant effects were obtained for the influence of experimenter gender on contractility and cardiac output responsivity to the speech stressor. No significant experimenter effects were documented for the cold pressor.The above results confirm race and gender differences in magnitude of responsivity to laboratory challenges. Although experimenter characteristics did not exert a substantial influence on responsivity, significance was documented for a task that requires interpersonal interaction. Given the need for experimental protocols to exhibit lab-to-field generalizations, the influence of experimenter characteristics within this field should be considered within a contextual and socio-ecological model.


Psychology, Physiological

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