The responsivity of several cardiovascular measures to a computerized mental arithmetic stressor and a cold pressor stressor were investigated in 22 healthy adult subjects. The major findings were that the largely beta-adrenergically driven T-wave amplitude, pre-ejection period, R-wave to pulse interval, and left ventricular ejection time measures responded only to mental arithmetic; a significant decrease in cardiac output and increase in peripheral resistance was elicited during cold pressor; inter-beat interval and subjective stress ratings responded significantly to both stressors compared to baseline levels, but more intensely to mental arithmetic than cold pressor; blood pressure, stroke volume and the maximum of the first derivative of the raw impedance signal (dz/dt(max)) responded unspecifically to both stressors. These findings support the idea that cardiovascular responses to psychological challenge depends on the level of cognitive processing required for the task. In addition, the superfluousness of multiple variable usage to study cardiovascular reactivity in such paradigms is discussed.