Sex Differences in Neuroanatomy of the Human Mirror Neuron System: Impact on Functional Recovery of Ischemic Hemiparetic Patients

BACKGROUND: Considering the higher activity of mirror neuron system in females, they frequently have better performance in empathy, interpersonal sensitivity, and emotional recognition compared to males. OBJECTIVES: The purpose of this study was to assess whether gender difference in neuroanatomy of the human mirror neuron system has any impact on functional recovery of ischemic hemiparetic patients. PATIENTS AND METHODS: This single-blind clinical trial was conducted on 24 patients with cerebrovascular accident (CVA) in the age range of 45 - 60 years, referring at a rehabilitation center in Tehran, Iran, during 2013 - 2014. Sampling method was stratified random sampling. The subjects were assigned to 2 groups of 12 males and 12 females. Then, each group was randomly divided into 2 groups (totally 4 groups, n = 6 for each group): women watching functional movies, control women, men watching functional movies, and control men. Movies were shown to patients and then, they were evaluated by Timed Up and Go (TUG), Six-minute walk test (SMW), Barthel index (BI), and Berg balance scale (BBS). RESULTS: Comparison of all variables related to functional activities of all groups before and after watching movies revealed significant differences. The highest percentage of change and improvement was observed in groups 1 and 3 watching the functional movies (P = 0.0001). Percentage of improvement in women of groups 1 and 2 was higher than men in groups 3 and 4 (P = 0.0003). The changes in group of females watching the functional movies (group 1) were significantly greater than in other groups (P < 0.0001). CONCLUSIONS: The Sex differences in the neuroanatomy of the human mirror neuron system affect functional recovery of patients with hemiparesis. The improvement in studied women was found to be significantly greater than studied men. The results indicate a higher chance of recovery among hemiparetic women, especially those watching functional movies.