Age differences in reading with distraction: sensory or inhibitory deficits?

Two experiments examined how sensory acuity affects age differences in susceptibility to interference in the reading-with-distraction task. In both experiments, older and younger adults read texts in an italic font and were required to ignore distractor words in an upright font. Experiment 1 examined whether the age-related increase in distractibility can be simulated in younger adults by reducing their visual acuity. Experiment 2 investigated whether the age differences in distractibility disappear if visual acuity is equated across all participants in both age groups. Both experiments showed that an impairment in visual acuity leads to increased interference in the reading-with-distraction task. However, older adults were much more impaired by the distractor material than younger adults with reduced visual acuity (Experiment 1). The age differences in the reading-with-distraction task persisted when visual acuity was equated between older and younger adults (Experiment 2). We conclude that the age-related increase in susceptibility to interference in the reading-with-distraction task is not solely due to perceptual deficits of older adults but arises from a deficit in higher cognitive processes such as inhibitory attention. Nevertheless, sensory acuity has to be taken into account as a potential confounding factor in perceptually demanding visual attention tasks.