Age-related decline of visual processing components in change detection

Abstract

Previous research has suggested that an age-related decline in change detection may be due to older adults using a more conservative response criterion. However, this finding may reflect methodological limitations of the traditional change detection design, in which displays are presented continuously until a change is detected. Across 2 experiments, the authors assessed adult age differences in a version of change detection that required a response after each pair of pre- and postchange displays, thus reducing the potential contribution of response criterion. Older adults performed worse than younger adults, committing more errors and requiring a greater number of display cycles for correct detection. These age-related performance declines were substantially reduced after controlling statistically for elementary perceptual speed. Search strategy was largely similar for the 2 age groups, but perceptual speed was less successful in accounting for age-related variance in detectability when a more precise spatial localization of change was required (Experiment 2). Thus, the negative effect of aging in the present tasks lies in a reduction of detection efficiency due largely to processing speed, though some strategy-level effects may also contribute. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Figure 1

Stimuli and course of events in a typical trial of Experiment 1. After each display of the image-pairs, participants gave their detection response: didn't see, possibly saw but needing to verify, and saw. The image-pairs were repeatedly shown when participants indicated a negative detection response. When participants responded with positive detection, they were prompted to indicate whether the changed item was located on the left or right side of the display.

Figure 2

Hits minus false alarms (A) and cycles to detection (B) measures of Experiment 1, as a function of age group. Error bars represent standard errors.

Figure 3

Stimuli and course of events in a typical trial of Experiment 2. After each display of the image-pairs, participants used the mouse to click on the screen indicating where they thought the changed item was located. After each localization response, participants indicated a detection response: didn't see, possibly saw but needing to verify, and saw. The image-pairs were repeatedly shown until either correct or failed detection.

Figure 4

Hits minus false alarms (A) and cycles to detection (B) measures of Experiment 2, as a function of age group. Error bars represent standard errors.

Figure 5

Illustration of the temporal integration and focused attention models, with hypothetical localization error for change trials leading to correct detection, as a function of model type and cycles prior to detection. Cycle -1 represents the display-pair presented immediately prior to correct detection (Cycle 0, not displayed). Older adult performance will approximate the temporal integration model if they perform change detection with a more conservative response criterion compared to younger adults.

Figure 6

Mean localization error (in cm) for change trials with successful detection of the changed item, as a function of age group and cycles prior to detection.