Negative Aging Stereotypes Disrupt both the Selection and Execution of Strategies in Older Adults.

BACKGROUND: Age-based cognitive deficits are exacerbated by stereotype threat effects (i.e., the threat of being judged as cognitively incapable due to aging). We tested whether age-based stereotype threat effects can occur via impair- ing older adults' ability to select the best strategy and/or to execute strategies efficiently. METHODS: Older adults (age range: 64.3-89.5 years) were randomly assigned to a stereotype threat or control condition before taking an episodic memory task. They encoded pairs of concrete words and of abstract words, with either a repetition or an imagery strategy, and then took a cued-recall task. Whereas participants in experiment 1 could choose between these two strategies, those of experiment 2 were forced to use either the repetition or the imagery strategy. RESULTS: Our findings showed that age-based stereotype threat disrupts both the selection and execution of the most efficient, but also most resource-demanding, imagery strategy, and that these stereotype threat effects were stronger on concrete words. CONCLUSION: Our findings have important implications to further understand age-based (and other) stereotype threat effects, and how noncognitive factors modulate age-related changes in human cognition.

Age-related differences in children's strategy repetition: A study in arithmetic.

Third and fifth graders (Experiment 1) and fifth and seventh graders (Experiment 2) accomplished computational estimation tasks in which they provided estimates to two-digit arithmetic problems (e.g., 34+68). Participants saw trials, each including three consecutive problems. Each trial was separated by a letter judgment task (i.e., participants needed to say whether a series of four letters included only vowels, only consonants, or both types of letters). On each problem, children were asked to select the better of the following strategies: rounding down (i.e., rounding both operands down to the nearest decades; e.g., 30+60=90) or rounding up (rounding both operands up to the nearest decades; e.g., 40+70=110). Half of the trials were repeated strategy trials (i.e., the better strategy was the same for the first two prime problems and the last target problem) and half were unrepeated strategy trials (i.e., the better strategy was different for prime and target problems). We found that (a) children repeated the same strategy over successive problems, even when they should change strategies to obtain better performance, (b) strategy repetitions decreased with age, (c) repeating the same strategy gave children performance benefits, and (d) these strategy repetition benefits were similar across grades. These effects of strategy repetition during strategy selection and strategy execution have important empirical and theoretical implications regarding how children choose among strategies, how children execute selected strategies on each problem, and how strategic variations change with age.

Age-related differences in sequential modulations of problem-size and rule-violation effects during arithmetic problem verification tasks.

Young and older adults were asked to verify true (e.g., 5 × 61 = 305) and false (5 × 61 = 315) arithmetic problems. Half the problems were small (e.g., 5 × 17 = 85) and half were large problems (e.g., 5 × 93 = 465). Half the false problems respected the five rule (i.e., the product of an operand multiplied by five ends with either 5 or 0), and half violated this rule (e.g., 21 × 5 = 115 vs. 21 × 5 = 113). Both young and older adults showed problem-size effects (i.e., they verified small problems more quickly than large problems) and five-rule violation effects (i.e., they verified problem violating five rule more quickly than problems respecting five rule). Moreover, we found sequential modulations of these problem-size and five-rule effects. Problem-size effects were larger on current problems following large problems than after small problems, and five-rule violation effects were larger after problems violating the five rule than after no-rule violation problems. Finally, sequential modulations of problem-size effects were larger in older adults than in young adults, and there were no age-related differences in sequential modulations of five-rule violation effects. These findings speak to the determiners of arithmetic performance, as to how well arithmetic calculation and non-calculation strategies are executed and selected on current problems depends on strategies used with preceding problems.

Effects of strategy sequences and response-stimulus intervals on children's strategy selection and strategy execution: a study in computational estimation.

The present study investigates how children's better strategy selection and strategy execution on a given problem are influenced by which strategy was used on the immediately preceding problem and by the duration between their answer to the previous problem and current problem display. These goals are pursued in the context of an arithmetic problem solving task. Third and fifth graders were asked to select the better strategy to find estimates to two-digit addition problems like 36 + 78. On each problem, children could choose rounding-down (i.e., rounding both operands down to the closest smaller decades, like doing 40 + 60 to solve 42 + 67) or rounding-up strategies (i.e., rounding both operands up to the closest larger decades, like doing 50 + 70 to solve 42 + 67). Children were tested under a short RSI condition (i.e., the next problem was displayed 900 ms after participants' answer) or under a long RSI condition (i.e., the next problem was displayed 1,900 ms after participants' answer). Results showed that both strategy selection (e.g., children selected the better strategy more often under long RSI condition and after selecting the poorer strategy on the immediately preceding problem) and strategy execution (e.g., children executed strategy more efficiently under long RSI condition and were slower when switching strategy over two consecutive problems) were influenced by RSI and which strategy was used on the immediately preceding problem. Moreover, data showed age-related changes in effects of RSI and strategy sequence on mean percent better strategy selection and on strategy performance. The present findings have important theoretical and empirical implications for our understanding of general and specific processes involved in strategy selection, strategy execution, and strategic development.

Effects of Prior-Task Success on Young and Older Adults' Cognitive Performance an Evaluation of the Strategy Hypothesis.

In prior-task success, older adults improve cognitive performance on target tasks after successfully accomplishing a prior task. We tested the hypothesis that effects of prior-task success occur via older adults' selecting the better strategy more often and executing strategies more efficiently on each problem under a prior-task success condition. Young and older participants accomplished computational estimation tasks (i.e., providing the best estimates to arithmetic problems) under a success or a control condition. They successfully accomplished a Stroop task or accomplished no prior task before taking the target arithmetic task. Participants had to select the better strategy on each problem in Experiment 1 and to execute a cue strategy in Experiment 2. Consistent with the strategy hypothesis, older adults, but not young adults, (a) obtained better performance, (b) used the better strategy more often, (c) inappropriately repeated the same strategy less often across successive problems, and (d) executed strategies more efficiently, under a prior-task success condition relative to a control condition. These results highlight the role of strategic variations in effects of prior-task success. They have important implications when assessing age differences in human cognition during both normal and pathological aging.

Adults' age-related differences in strategy perseveration are modulated by response-stimulus intervals and problem features.

Ageing results in the tendency of older adults to repeat the same strategy across consecutive problems more often than young adults, even when such strategy perseveration is not appropriate. Here, we examined how these age-related differences in strategy perseveration are modulated by response-stimulus intervals and problem characteristics. We asked participants to select the best strategy while accomplishing a computational estimation task (i.e., provide approximate sums to two-digit addition problems like 38 + 74). We found that participants repeated the same strategy across consecutive problems more often when the duration between their response and next problem display was short (300 ms) than when it was long (1300 ms). We also found more strategy perseverations in older than in young adults under short Response-Stimulus Intervals, but not under long Response-Stimulus Intervals. Finally, age-related differences in strategy perseveration decreased when problem features helped participants to select the best strategy. These modulations of age-related differences in strategy perseveration by response-stimulus intervals and characteristics of target problems are important for furthering our understanding of mechanisms underlying strategy perseveration and, more generally, ageing effects on strategy selection.