Vascular Response Differences in Field Dependency

Field-dependent (FD) subjects (Ss) differ psychophysiologically from field-independent (FI) Ss who are more differentiated psychologically and more cerebrally lateralized. This paper reviews vascular differences in these two groups in a series of five experiments. First noted was that withdrawing blood from FD Ss was more difficult, suggesting superficial vein constriction or spasm. Additionally, FD Ss did not respond to insulin-induced hypoglycemia with the expected pulse rate and systolic blood pressure rise and diastolic decrease, while FI Ss did show these changes. In a second experiment, arm veins of FD Ss revealed higher resting pressures than FI Ss, until after stimulation. Both groups displayed similar higher pressures during nonspecific stimuli (white noise), while FI Ss responded more to specific stimuli (words, arithmetic). A third experiment investigating the rate of blood flow in a superficial arm vein demonstrated decreasing resting rates over time only in FD Ss; while overall, FI Ss revealed faster resting rates, and in sustained response to a dose of epinephrine. A fourth and fifth experiment exposing these groups to different doses of epinephrine or alcohol revealed poorer dose responses among FD Ss with diastolic blood pressure and pulse rates. These Ss appear to be more responsive to novelty than to differing dose levels of CNS active drugs or other specific stimuli.