Task-switching inefficiencies in currently ill, but not remitted anorexia nervosa

Models of anorexia nervosa (AN) posit that set-shifting deficits may contribute to behavioral inflexibility and extreme dietary restriction. Findings from neurocognitive studies of set-shifting in AN have been somewhat mixed, perhaps due to the use of tasks that cannot distinguish shifting from other processes (i.e., learning). To more precisely characterize cognitive flexibility and selectively assess this process independent of rule learning and feedback sensitivity, we examined task-switching ability in AN.

Women ill with AN, subthreshold AN or atypical AN (IAN; n = 40), women remitted from AN (RAN; n = 24), and age-matched healthy control women (n = 42) completed a computerized cued color-shape task-switching paradigm. Groups were compared on mix costs (reflecting global cognitive control) and switch costs (reflecting transient cognitive control).

Although mix costs were equivalent across groups, switch costs were more pronounced in the IAN group, as indicated by a group-by-trial type interaction for reaction times on stay and switch trials.

Findings indicate that IAN, but not RAN, have difficulty flexibly switching between cognitive task sets, and suggest that prior findings of set-shifting deficits in AN may reflect difficulty with cognitive flexibility independent of learning deficits. As such, task-switching may represent a promising adjunctive treatment target.