Cognitive Patterns of Coma Patients Induced by Severe Traumatic Brain Injury in Working Memory

Background and Aim: Coma caused by severe traumatic brain injury, leads to cognitive function disorder, the most frequently affects being on the working memory. Because of the importance and direct impact of working memory on the quality of human life, especially in military skills that require active memory and high attentional power; the present study aimed to investigate the cognitive patterns of patients coma in working memory. Methods: In this causal-comparative study, which was conducted from February 2017 to July 2019, two groups of individuals were selected by available sampling method. 20 comatose patients, aged 30-55 years, who had returned from coma during last year and were admitted to ICU ward of Haft-e-Tir and Baqiyatallah hospitals in Tehran, Iran, were included as the experimental group and 64 healthy individuals with the same age range considered control group. All participants were male and were assessed by Wechsler working memory. The performance of the two groups was compared using multivariate analysis of variance. Results: The difference between the two groups in the visual memory span was statistically significant (p <0.05) and the difference between the two groups in other subdomains of working memory test were statistically significant (p <0.01). In general, coma patients showed a poorer performance than the healthy group.  Conclusion: Coma caused by severe traumatic brain injury, can disturb executive functions of the brain's prefrontal lobes after one year and impair patients' working memory. Hence, it is strongly suggested that in clinical and legal evaluations of the patients, this issue to be considered and both psychological and medical interventions done simultaneously to facilitate the treatment process and cognitive rehabilitation of the patients and to prevent individual, social and financial consequences and costs associated with a coma.