Asymmetry in hand grip strength and fatigue in low- and high-hostile men.

The present study examined the relationship between hostility level and cerebral hemispheric motor functioning of 70 left-cerebral dominant men. Using the Cook-Medley Hostility Scale, the subject group was divided into thirds: One-third (N = 23) were classified as low-hostile, one-third (N = 23) were classified as high-hostile, and the remainder (N = 24) were excluded from analysis. A hand dynamometer was used to assess hand grip strength, perseveration, and fatigue, as measures of hemispheric motor functioning. Results yielded a hand-by-hostility group interaction, which indicated that high-hostile men evidenced significantly less hand grip strength at the right hand and significantly greater hand grip strength at the left hand relative to low-hostile men. These results suggest that high-hostile men may experience relatively greater right-cerebral arousal relative to their low-hostile counterparts. In other results, both groups showed greater perseveration at the left hand than at the right hand. Both groups also showed significant fatigue across trials at both hands. Analysis also revealed a hand-by-trial interaction, indicating that the right hand fatigued more quickly than the left hand across trials. Resistance to fatigue at the left hand and overestimation or relative imprecision in motor movement at the left hand are discussed in terms of arousal theory. These results and others are cited as contributing inroads into distinguishing between the emotional problems of depression, anxiety, and hostility.