Identifying the learning capabilities of older adults. Associative and priority learning

Effective search performance is determined by two important factors: memory load and display load. Memory load factors can be reduced by 'associative learning' where memory-set elements become unitized and the stimuli are compared as a 'category' rather than serially. Display-load effects can be reduced by target-distractor differentiation, process referred to as 'priority learning'. In this paper we describe a three-phased experiment conducted to examine how those factors affected search performance for young and old subjects (mean ages, 24 and 71). Subjects were first trained in two varied mapping (VM) conditions (Phase 1): (1) Associative - allowed unitization of the stimulus sets; (2) Nonassociative - inhibited unitization. In Phase 1 all subjects unitized the associative sets thus implying maintenance of associative learning. In Phase 2, the stimuli were consistently mapped (CM) thus allowing the opportunity for priority learning. Following CM training young adults' performance was qualitatively superior to old adults'. In Phase 3, the CM target distractor roles were reversed to assess the strength of CM learning. The attention-capturing strength (a measure of priority learning) was age-dependent with young adults showing greater effects. The results demonstrate that age differences in perceptual learning are primarily a function of a disruption in priority learning.