The inability to suppress irrelevant information has been suggested as a primary cause of proactive interference (PI), and this deficit may be enhanced in aging. The current study examines age differences and temporal boundaries of PI, by manipulating lure distances in a verbal 2-back working memory task. Both younger and older adults showed effects of interference for proximal 3- and 4-back lures, and this effect was greater for older adults. Whereas younger adults showed less interference during 4-back compared to 3-back lures, in both reaction times and accuracy, older adults improved only in accuracy. For distant lures, when the time between the 1st presentation of an item to its reappearance as a lure item was longer (e.g., 5- to 10-back lures), younger adults were no longer affected by PI. However, older adults were affected by PI throughout all distant lures, up to the most distant lure (9-/10-back). The results suggest that older adults were less successful in resolving interference from both proximal and distant familiar lures. Further, younger adults were able to overcome the effects of PI completely after a specific lure distance. The age differences in temporal properties of PI may therefore highlight a unique component linked to impaired interference control and aging. (PsycINFO Database Record

Age-related declines in attention and working memory (WM) are well documented and may be worsened by the occurrence of distracting information. Emotionally valenced stimuli may have particularly strong distracting effects on cognition. We investigated age-related differences in emotional distraction using task-fMRI. WM performance in older adults was lower for emotional compared with neutral distractors, suggesting a disproportional impairment elicited by emotional task-irrelevant information. Critically, older adults were particularly distracted by task-irrelevant positive information, whereas the opposite pattern was found for younger adults. Age groups differed markedly in the brain response to emotional distractors; younger adults activated posterior cortical regions and the striatum, and older adults activated frontal regions. Also, an age by valence interaction was found for IFG and ACC, suggesting differential modulation of attention to task-relevant emotional information. These results provide new insights into age-related changes in emotional processing and the ability to resolve interference from emotional distraction.Electronic supplementary materialThe online version of this article (10.3758/s13415-018-0610-8) contains supplementary material, which is available to authorized users.

Many real-life situations require flexible behavior in changing environments. Evidence suggests that anticipation of conflict or task difficulty results in behavioral and neural allocation of task-relevant resources. Here we used a high- and low-interference version of an item-recognition task to examine the neurobehavioral underpinnings of context-sensitive adjustment in working memory (WM). We hypothesized that task environments that included high-interference trials would require participants to allocate neurocognitive resources to adjust to the more demanding task context. The results of two independent behavioral experiments showed enhanced WM performance in the high-interference context, which indicated that a high-interference context improves performance on non-interference trials. A third behavioral experiment showed that when WM load was increased, this effect was no longer significant. Neuroimaging results further showed greater engagement of inferior frontal gyrus, striatum, parietal cortex, hippocampus, and midbrain in participants performing the task in the high- than in the low-interference context. This effect could arise from an active or dormant mode of anticipation that seems to engage fronto-striatal and midbrain regions to flexibly adjust resources to task demands. Our results extend the model of conflict adaptation beyond trial-to-trial adjustments by showing that a high interference context affects both behavioral and biological aspects of cognition.