Age-related differences in memory for lateral orientation of pictures

Two experiments examined memory for the lateral orientation of scenic pictures by young and elderly adults. In experiment 1, an input list of pictures was followed by a test demanding discrimination between (a) targets versus reversed copies of input items, or (b) targets versus new pictures which verbally resembled input items. The age-related difference was reliably larger in the former task than in the latter. Experiment 2 compared incidental versus intentional acquisition of orientation under conditions of short (1 second) and long (5 second) presentation of pictures at input. With short presentation, though not with long presentation, intentional instructions reliably impaired orientation memory. With both presentation times, robust age-related differences were obtained. The results suggest an age-related deficit in truly non-intentional encoding of orientation, and pose a challenge for capacity theories of memory across the lifespan.