Kalakoski, V. , Akila, R. , Vuori, M. & Puttonen, S.
Finnish Institute of Occupational Health. Helsinki, Finland
The ability to perform complex cognitive tasks requires working memory (WM). In work assignments there are several factors that may impair WM functioning. We studied whether long-term exposure to high psychosocial stress, i.e. a combination of high job demands and low job decision latitude, is related to impaired WM capacity. As a part of a large research project, the WM capacity of 99 nurses (n = 43 in High Work Stress Group and n = 56 in Low Work Stress Group) was measured. Visuo-spatial WM span was estimated with a computer-based Symmetry span test consisting of storage of a set of locations, and processing of symmetry information (Kane et al. 2004). Verbal WM span was assessed with an operation span task consisting of word lists to be remembered and arithmetic operation tasks (Turner & Engle, 1989). The High Work Stress group showed a somewhat smaller WM capacity than the Low Work Stress group, suggesting that high work load impairs working memory functioning. We discuss the interaction of workload with other factors, e.g. age, and whether the observed lower performance level in WM tasks is explainable by other cognitive functions, such as inefficiency of visual search or short-term memory encoding.