No abstract

The authors used a lexical-decision task in 3 different experiments to examine whether age differences in word recognition were consistent across processing stage. In all experiments, word frequency and length were manipulated. In Experiments 1 and 2, encoding difficulty was varied, and in Experiment 3, response selection difficulty was varied. In all 3 experiments, there were no age differences for word frequency. However, in Experiments 1 and 2, older adults showed a larger decrement for encoding. In Experiment 3, age differences were larger when response selection load increased. These results suggest that age differences in word recognition occur because older adults exhibit primarily peripheral-rather than central-processing decrements. The implications of these data for generalized and localized slowing models are discussed.

Young and older adults performed a memory search task in which, before probe onset, a cue indicated which of 4 memory-set items the probe was most likely to be. The results were consistent with an attentional allocation model in which performance represents a weighted combination, across trials, of focused (i.e., selective) versus distributed attention. The model significantly underestimated the reaction time required by miscued trials, probably because of the response inhibition occurring on these trials. The degree to which Ss relied on focused attention was significantly greater for older adults than for young adults. The estimated time required to shift attention between memory-set items was equivalent for the 2 age groups.

Older and young adults' letter detection and lexical decision performance were examined as word frequency varied to determine whether there were age differences in word recognition. Allen and Madden (1989) found that older adults' pattern of reaction time (RT) across word frequency categories was different from young adults' pattern for a letter detection task. In this study, for both letter detection and lexical decision tasks, older adults exhibited a monotonically decreasing RT function as word frequency increased. However, young adults exhibited a nonmonotonic RT function across word frequency for the letter detection task but a monotonically decreasing RT function as word frequency increased for the lexical decision task. An expanded parallel input serial analysis model of word processing was hypothesized.

I investigated adult age differences in the efficiency of feature-extraction processes during visual word recognition. Participants were 24 young adults (M age = 21.0 years) and 24 older adults (M age = 66.5 years). On each trial, subjects made a word/nonword discrimination (i.e., lexical decision) regarding a target letter-string that was presented as the final item of a sentence context. The target was presented either intact or degraded visually (by the presence of asterisks between adjacent letters). Age differences in lexical decisions speed were greater for degraded targets than for intact targets, suggesting an age-related slowing in the extraction of feature-level information. For degraded word targets, however, the amount of performance benefit provided by the sentence context was greater for older adults than for young adults. It thus appears that an age-related deficiency at an early stage of word recognition is accompanied by an increased contribution from semantic context.

Previous research has suggested that an age-related decline may exist in the ability to inhibit distracting information during visual search. The present experiments used a conjunction search task in which the within-item features of the target (an upright L) and the distractors (rotated Ls) were identical. In each of 2 experiments, both young and older adults searched the display significantly more rapidly when the distractors were all rotated in the same direction (homogeneous) than when the distractors were rotated in different directions (heterogeneous). The concept of a generalized, age-related slowing was able to account for many aspects of the data, although the degree of relative improvement associated with distractor homogeneity was greater for young adults than for older adults.

A parallel input serial analysis (PISA) model of word processing was developed and tested. The goal was to expand on the "critical processing duration" hypothesis of Johnson, Allen, and Strand (1989) so that both single-word and multiple-word presentation, letter detection data could be explained. In Experiments 1-3 four different word frequency categories on a single-presentation, letter detection task were used. These three experiments indicated that there was a curvilinear relationship between word frequency and letter detection reaction time (RT). That is, letter detection RTs for medium-high-frequency words were significantly longer than letter detection RTs for very-high-, low-, and very-low-frequency words. These results support the PISA model rather than the Healy, Oliver, and McNamara (1987) version of the unitization model. In Experiments 4-5 multiple-presentation (i.e., two words), letter detection tasks were used. The PISA model could also account for the results from these two experiments, but the unitization model could not.

A case study of the renovation of New York City's Bryant Park, this article revisits the end of public space thesis. The renovated park signifies not the end of public space but the new ends to which public space is oriented. In Bryant Park, a new logic of urban publicity was assembled and built into the landscape. The social and technical means by which this transformation was achieved are analyzed. New public spaces of this sort promulgate a conception of the public that is decoupled from discourses of democratization, citizenship, and self‐development and connected ever more firmly to consumption, commerce, and social surveillance. If such places do not herald the end of public space, they do represent “publicity without democracy.”