Are There Differences in Left and Right-Handers Performance on Cognitive Functions in the Context of Deficits in Post-Traumatic Stress Disorder?

Abstract

Post Traumatic Stress Disorder (PTSD) is a possible consequence of any traumatic event in which a person experiences high levels of fear, helplessness or horror. The estimated lifetime prevalence of PTSD is 7.8% within the American population, where prevalence of PTSD is twice as common in women than in men (Kessler et al., 1995). Evidence has suggested that prevalence of PTSD was doubled (15%) in left-handers in comparison to those who are right handed (8%) (Choudhary and O'Carroll, 2007). Furthermore, research has shown that when individuals are exposed to a situation involving fear, left-handers apparently perform similarly to people with PTSD. The current study investigated performance on several cognitive tasks (verbal memory, visual memory, attention, verbal fluency and central executive function) within a non-clinical population between left ad right-handed individuals after eliciting fear. Fear was induced through the use of a fictional film, previously identified as targeting fear (Gross and Levenson, 1995). The study found better performance on visioconstructive skills in left-handers when compared to the right-handed subjects, where results on working memory and central executive function were consistent with previous research findings- there were no differences in handedness or sex after the fearful film. In line with previous findings, women displayed better performance on verbal memory, however, verbal fluency measures were greater in males than females. Recruiting equal number of sexes to the conditions, as well as handedness, may be worthwhile to investigate further.