The effects of psychosocial and cognitive stress on executive functions and automatic processes in healthy subjects: A pilot study

The main aim of the present study was to examine the effects of psychosocial and cognitive stress on executive functions and automatic processes in healthy subjects. To achieve these purposes, we investigated whether cognitive stress impaired the controlled processing underlying cognitive flexibility, working memory and initial letter fluency performances, and whether social stress impaired both performance of executive processes and of semantic fluency. We employed the psychosocial stress paradigm in which cognitive assessment was superimposed on cognitive and social stressors soon after their introduction and was carried out concurrently while they were present. With reference to cognitive stress, we employed the dual-task paradigm that involves a primary task (performances related to executive functions and automatic task) and a secondary task (focusing attention and memorizing items in another cognitive task). Eighty-eight healthy subjects, between 18 and 30 years, participated in this study. They were randomly divided into three groups: two groups undergoing a stress procedure, respectively a cognitive stress group and a social stress group, and a control group. Results indicated that stress impaired cognitive flexibility, working memory and verbal fluency. Cognitive flexibility was affected to a greater extent by psychosocial stress than cognitive stress. This study suggests that the negative effects of stress on cognitive flexibility may be a consequence of the interplay between controlled and automatic processes.