Functional cerebral asymmetry in hostility: a dual task approach with fluency and cardiovascular regulation.

The influence of hostility levels on verbal and nonverbal fluency, and the concurrent cerebral regulation of autonomic nervous system functioning was examined in 48 right-handed males, half classified as low-hostile, and half as high-hostile. Recent research has supported inhibitory roles for the anterior right cerebrum in sympathetic regulation, and the anterior left cerebrum in parasympathetic regulation. Two neuropsychological tests purportedly mediated by left and right anterior cerebral systems, respectively, are the Controlled Oral Word Association Test and the Ruff Figural Fluency Test. Fluency and perseverative errors were assessed using these measures. Systolic and diastolic blood pressure, and heart rate were assessed with a digital blood pressure meter. It was predicted that high-hostile men would evidence interference on cardiovascular regulation concurrent with the nonverbal fluency task in comparison to low-hostile males. Further, interference was expected to manifest in the cognitive variable with more perseverative errors on the nonverbal fluency task in high-hostile males than in low-hostile males. The results support a capacity-limited prediction. High-hostile males evidenced significantly heightened systolic blood pressure during the nonverbal fluency task in comparison with low-hostile males. Further, high-hostile males displayed more perseverative errors in nonverbal fluency than did the low-hostile males. These results support the expectation that differences exist between high- and low-hostile males for right frontal functioning. These findings were discussed within the proposed anterior-posterior inhibition model of hostility.