In naturalistic tasks, subjects often interact with a cluttered visual environment in which they need to divide their attention simultaneously among multiple objects and tasks. Previous work examining the effects of aging in tasks that approximate these real world demands have shown that performance often declines with age. For example, when subjects must perform central and peripheral visual tasks simultaneously in a Useful Field of View (UFOV) task, performance on the peripheral task declines relative to when subjects perform the peripheral task alone, and this divided-attention deficit grows decade-by-decade throughout our lifetimes [e.g., Sekuler, A.B., Bennett, P.J., and Mamelak, M. (2000). Effects of Aging on the Useful Field of View. Experimental Aging Research, 26, 103-120]. Here, we investigated the extent to which age-related differences in divided-attention could be overcome with practice. In addition, we assessed how divided attention costs varied when initial performance levels were equated across age groups at the start of practice. Experiment 1 determined the stimulus durations that approximately equated attentional costs for younger and older subjects. These stimulus durations were used in Experiments 2 and 3 to equate task difficulty across age. Experiments 2 and 3 examined the effect of practice for 1-2 weeks. Practice improved performance for both younger and older subjects, and, when older subjects were provided with enough practice, their attentional costs were equivalent to those of younger subjects. Indeed, with enough practice, both younger and older subjects reached a point where they showed no divided-attention deficits, although older subjects may need more practice to reach this point. Finally, the beneficial effects of practice were maintained for at least three months.

People with autism spectrum disorders appear to have some specific advantages in visual processing, including an advantage in visual search tasks. However, executive function theory predicts deficits in tasks that require divided attention, and there is evidence that people with autism have difficulty broadening their attention (Mann & Walker, 2003). We wanted to know how robust the known attentional advantage is. Would people with autism have difficulty dividing attention between central and peripheral tasks, as is required in the Useful Field of View task, or would they show an advantage due to strengths in visual search? Observers identified central letters and localized peripheral targets under both focused- and divided-attention conditions. Participants were 20 adults with high-functioning autism and Asperger's syndrome and 20 adults matched to the experimental group on education, age, and IQ. Contrary to some predictions, individuals with autism tended to show relatively smaller divided-attention costs than did matched adults. These results stand in stark contrast to the predictions of some prevalent theories of visual and cognitive processing in autism.

This study scrutinized people’s ability to apply different strategies to randomly intermixed immediate and delayed test items. In three experiments, participants first read one set of stories. Later, they read more stories, and after each one, answered intermixed questions about that story and one of the earlier ones. The experiments cumulatively manipulated amount of delay, test probe plausibility, probe relation (explicit, paraphrase, inference), and testing procedure (mixed versus uniform delay). Using signal detection response criterion as the index of strategy, we contrasted the single criterion hypothesis, according to which one text retrieval criterion is applied to all test items, and a multiple-criterion hypothesis. The results consistently favoured the multiple-criterion hypothesis. The results also indicated that the presence of immediate and delayed probes mutually influence one another: Less extreme signal detection criteria were adopted under mixed than uniform testing. It was concluded that text retrieval strategy is continually calibrated with reference to the quality of the test probes.

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