Age differences in implicit memory: fragmented object identification and category exemplar generation.

In a cross-sectional study of 164 participants aged 21 to 91, the authors examined age differences on two implicit tests, fragmented object identification (FOI) and category exemplar generation (CEG), and on tests of explicit memory, attention, and verbal fluency. FOI results revealed impaired perceptual skill learning in those over 60 and a decrease in perceptual priming across young, middle-aged, and older groups. CEG priming was impaired in those over 80. Regression analysis revealed explicit contamination of priming on both the FOI and CEG tests. Across the three implicit measures, age accounted for 4 to 13% of the variance when explicit memory was controlled. Semantic fluency predicted CEG priming, suggesting possible frontal lobe involvement on the test. Altogether, results indicate that age has a small but reliable influence on implicit memory.     

Age and gender differences in implicit motives

Research on age differences in implicit motives is rare and has shown contradictory results. We investigated age and gender differences in implicit motives (achievement, power, affiliation and intimacy), measured by the Picture Story Exercise (PSE), in an extensive, heterogeneous dyadic sample of 736 adults aged 20–80 years. Data were analyzed with a multilevel approach. Results indicate lower motive scores in all four measured motives in aged as compared to young adults but higher scores in activity inhibition. Further, women scored higher in affiliation and intimacy motives than men, while men scored higher in achievement and power motives and in activity inhibition than women. Possible underlying affective and neuroendocrinological processes of age dependent change in implicit motives are discussed.     

Age differences in recognition memory

It is generally believed that short-term memory (STM) performance decreases from maturity to old age, but the present paper questions the generality of this conclusion. The first experiment reported is a short-term recognition probe study—no significant age differences were found in either acquisition or the rate of forgetting. It is suggested that age decrements in STM are limited to situations where attention is divided at input or where the material must be manipulated during storage. Experiment II confirmed previous findings of minimal age losses in secondary memory word recognition. The results of this second study support the conclusion that there is poorer accessibility to stored verbal material with advancing age.     

Age differences in memory span

Five-year-olds recalled fewer items than adults in memory-span tasks involving both familiar and unfamiliar faces. This occurred even though the use of rehearsal and recoding strategies was minimized for adults. This residual age difference may be partially accounted for by two further processing limitations in children. The five-year-olds needed more time than adults to name a face (Experiment 1) and to encode a face (Experiment 2). In order to test whether limitations in children's initial recognition and stimulus-identification processes could account for recall performance, Experiment 3 reduced adults' exposure duration in the memory-span task. This led to a drastic reduction in the age difference. Other factors contributing to remaining age differences included adults' adaptability in using various alternative encoding and retrieval strategies which elevated their recall performance.     

Age differences in visuospatial working memory

In two visuospatial working memory (VSWM) span experiments, older and young participants were tested under conditions of either high or low interference, using two different displays: computerized versions of a 3 x 3 matrix or the standard (randomly arrayed) Corsi block task (P. M. Corsi, 1972). Older adults' VSWM estimates were increased in the low-interference, compared with the high-interference, condition, replicating findings with verbal memory span studies. Young adults showed the opposite pattern, and together the findings suggest that typical VSWM span tasks include opposing components (interference and practice) that differentially affect young and older adults.     

Gender differences in implicit and explicit memory for affective passages

Thirty-two participants were administered 4 verbal tasks, an Implicit Affective Task, an Implicit Neutral Task, an Explicit Affective Task, and an Explicit Neutral Task. For the Implicit Tasks, participants were timed while reading passages aloud as quickly as possible, but not so quickly that they did not understand. A target verbal passage was repeated three times, and alternated with other previously unread passages. The Implicit Affective and Neutral passages had strong affective or neutral content, respectively. The Explicit Tasks were administered at the end of testing, and consisted of multiple choice questions regarding the passages. Priming effects in terms of more rapid reading speed for the target compared to non-target passages were seen for both the Implicit Affective Task and the Implicit Neutral Task. Overall reading speed was faster for the passages with neutral compared to affective content, consistent with studies of the emotional Stroop effect. For the Explicit memory tasks, overall performance was better on the items from the repeated passage, and on the Affective compared to Neutral Task. The male subjects showed greater priming for affective material than female subjects, and a greater gain than female subjects in explicit memory for affective compared to neutral material.     

Counterintuitive cross-linguistic differences: More morphological computation in English than in Finnish

This study investigates the role of derivational morphology in lexical processing in two typologically quite different languages: Finnish and English. While Finnish is a language with an extremely rich morphology, English morphology is relatively poor. Consequently, the role of morphology in storing and processing words would be expected to be greater in Finnish than in English. With a series of visual lexical decision experiments in both languages, we find that the opposite is the case for derivational morphology: for English, parsing of morphological constituents is often required, whereas for Finnish, full-form storage and access seems to be the rule. We try to explain this counterintuitive finding by making an appeal to the lexical-statistical properties of both languages.     

Age differences in visual and kinesthetic short-term memory

30 elderly subjects were matched with 30 young subjects and tested on a kinesthetic short-term memory task which required the replication of criterion moves after a variable retention interval under conditions of either rest, differing interpolated movement tasks, or mental activity. A visual control condition was used. Differing interference and temporal decrements were observed. Both old and young subjects differed significantly between sighted and blindfold conditions; however, there was no difference between the performance of the old and the young in the blindfold (kinesthetic) condition. These findings were discussed with respect to practical implications for the retraining of old subjects on certain motor tasks.     

Age differences in self-set goal effects for memory

Research has shown that goal setting leads to gains in memory performance and memory self-efficacy across adulthood when goals are set by experimenters and accompanied by positive feedback. However, self-set memory goals have had less consistent impact. This research extended past studies on aging and memory goals to examine the impact of self-set goals using anchors to guide goal selection. Two trials of name, text, and list recall were administered to younger and older adults, comparing goal and no-goal groups. After baseline, participants assigned to the goal group set personal goals for memory gain on a second, post-goal trial for each of the three tasks. Anchoring for goal-setting was used to encourage the selection of realistic, yet challenging goals. Younger and older participants set comparable goals. Only younger adults showed a motivational response (higher gains across trials for goals than no goals), even though older adults reported being just as committed to their personal goals. Older adults may have failed to show reliable goal-related gains because no positive feedback was offered or because they were unable to activate effective strategies for improved performance.     

Age and individual differences influence prospective memory

The influence of age and individual ability differences on event-based prospective memory was examined using an adapted version of G. O. Einstein and M. A. McDaniel's (1990) task. Two samples of younger and older adults who differed in educational attainment, occupational status, and verbal ability were compared. Results yield comparable prospective performance for the younger groups and higher ability older adults; lower ability older adults performed more poorly by comparison. Hierarchical regression analyses indicated that working memory span and recognition accounted for small but significant proportions of variance in prospective performance. The contribution of ability level to prospective memory remained significant even after statistically controlling for self-reported health and social activity characteristics. Implications for current views on prospective memory aging are discussed.     

Age differences in collaborative memory: the role of retrieval manipulations

In two experiments, we examined age differences in collaborative inhibition (reduced recall in pairs of people, relative to pooled individuals) across repeated retrieval attempts. Younger and older adults studied categorized word lists and were then given two consecutive recall tests and a recognition test. On the first recall test, the subjects were given free-report cued recall or forced-report cued recall instructions (Experiment 1) or free recall instructions (Experiment 2) and recalled the lists either alone or in collaboration with another subject of the same age group. Free-report cued recall and free recall instructions warned the subjects not to guess, whereas forcedreport cued recall instructions required them to guess. Collaborative inhibition was obtained for both younger and older adults on initial tests of free-report cued recall, forced-report cued recall, and free recall, showing that the effect generalizes across several tests for both younger and older adults. Collaborative inhibition did not persist on subsequent individual recall or recognition tests for list items. Older adults consistently falsely recalled and recognized items more than did younger adults, as had been found in previous studies. In addition, prior collaboration may exaggerate older adults’ tendency toward higher false alarms on a subsequent recognition test, but only after a free recall test. The results provide generality to the phenomenon of collaborative inhibition and can be explained by invoking concepts of strategy disruption and source monitoring.     

Age differences in skill acquisition and transfer in an implicit learning paradigm

Age differences in learning a complex cognitive skill are examined. The type of knowledge gained and levels of performance and transfer achieved, under different practice conditions, were compared in younger and older groups of trainees. The development of verbalizable knowledge about the task but not task performance itself varied as a function of age and practice condition. All trainees achieved transfer to novel versions of the task but older subjects appeared restricted to tasks drawn from the same semantic domain. The implications of these findings for developing training programmes for older workers are discussed.     

Age differences in prefrontal cortical activity in working memory

Working memory (WM) declines with advancing age. Brain imaging studies indicate that ventral prefrontal cortex (PFC) is active when information is retained in WM and that dorsal PFC is further activated for retention of large amounts of information. The authors examined the effect of aging on activation in specific PFC regions during WM performance. Six younger and 6 older adults performed a task in which, on each trial, they (a) encoded a 1- or 6-letter memory set, (b) maintained these letters over 5-s. and (c) determined whether or not a probe letter was part of the memory set. Comparisons of activation between the 1- and 6-letter conditions indicated age-equivalent ventral PFC activation. Younger adults showed greater dorsal PFC activation than older adults. Older adults showed greater rostral PFC activation than younger adults. Aging may affect dorsal PFC brain regions that are important for WM executive components.     

Adult age differences in implicit and explicit memory: time course and encoding effects

Young and older adults were tested at three delays on word-stem completion or cued recall following semantic or structural word judgments. Identical three-letter stems were present at retrieval for both implicit (completion) and explicit (cued recall) tasks; only the intention to recall list words differed. The young adults outperformed the older adults on both implicit and explicit tasks at all test delays. Under some conditions, the older but not the young adults performed more poorly on cued recall than on stem completion, suggesting a possible failure to use implicitly available information to support explicit remembering. These results suggest that some forms of implicit memory decline with normal aging.     

A Research Note: Happiness by Age is More Complex than U-Shaped

Happiness varies with age, but there is no general agreement regarding the feature of the variation. Many studies have found that it is U-shaped such that there is a minimum between approximately 40 and 50 years of age. The result largely depends on the control variables used in the happiness modeling. Some authors do not even allow the use of any control variables, but the conventional theory of U-shaped studies stipulates the inclusion of such controls that essentially influence the basic living conditions of people. In this study, we do not strictly follow earlier findings but estimate our age-shape with different versions of them, using the data of 28 or 30 European countries. We also estimate a model without proper controls. This does not give any minimum age and thus supports some studies. Moreover, using any or all of our three controls some type of U-shape is found in most countries. Our U-shapes are not as simple as conventional research suggests. Minimum happiness can occur either below 40 years, or much above 50 years. A special feature is that the U-shape phenomenon holds better for males than for females. We also estimated models to see what happens after the minimum age happiness. In the case of gender models, the turning points for males are substantially lower than for females. This means that the old-age happiness of males stops to increase approximately at 70 years but more than 10 years later for females.     

Familiarity is related to conceptual implicit memory: An examination of individual differences

Explicit memory is thought to be distinct from implicit memory. However, growing evidence has indicated that explicit familiarity-based recognition memory judgments rely on the same process that supports conceptual implicit memory. We tested this hypothesis by examining individual differences using a paradigm wherein we measured both familiarity and conceptual implicit memory within the same participants. In Experiments 1a and 1b, we examined recognition memory confidence ROCs and remember/know responses, respectively, to estimate recollection and familiarity, and used a free association task to measure conceptual implicit memory. The results demonstrated that, across participants, familiarity, but not recollection, was significantly correlated with conceptual priming. In contrast, in Experiment 2, utilizing a similar paradigm, a comparison of recognition memory ROCs and explicit associative cued-recall performance indicated that cued recall was related to both recollection and familiarity. These results are consistent with models assuming that familiarity-based recognition and conceptual implicit memory rely on similar underlying processes.     

Age differences in everyday memory: laboratory analogues of telephone number recall

Three experiments were conducted to examine age differences in memory for telephone numbers by adults ranging from 18 to 85 years of age. In the first 2 studies, using visual simultaneous presentation, age declines in immediate recall were evident on 10-digit numbers, but not on 3-digit numbers. With 7-digit numbers, the youngest group performed significantly better than the oldest (70-85 years) group. In the second study, more marked age declines occurred when subjects had to redial a number after a busy signal. The third experiment replicated the observed aging pattern with auditory sequential presentation. Also, chunked presentation of local telephone numbers resulted in high performance for old and young in sequential recall. The findings were discussed in relation to task processing demands and practical issues related to telephone number recall.     

We remember the good things: Age differences in learning and memory

We combined a feedback-based learning task with a recognition memory paradigm to investigate how reward-based learning affects the event-related potential (ERP) correlates of recognition memory in younger and older adults. We found that positive, but not negative learning improves memory and results in an increased early ERP old–new effect, which is typically associated with familiarity-based memory. This indicates that reward-based learning supports a fast and relatively automatic memory retrieval process. Furthermore, we found age-related impairments in reward-based learning, whereas memory for the learned information was intact in the elderly, suggesting that declarative memory might be less affected by aging.     

Age differences in memory control: evidence from updating and retrieval-practice tasks

Some contemporary approaches suggest that inhibitory mechanisms play an important role in cognitive development. In addition, several authors distinguish between intentional and unintentional inhibitory processes in cognition. We report two experiments aimed at exploring possible developmental changes in these two types of inhibitory mechanisms. In Experiment 1, an updating task was used. This task requires that participants intentionally suppress irrelevant information from working memory. In Experiment 2, the retrieval-practice task was used. Retrieval practice of a subset of studied items is thought to involve unintentional inhibitory processes to overcome interference from competing memories. As a result, suppressed items become forgotten in a later memory test. Results of the experiments indicated that younger children (8) were less efficient than older children (12) and adults at intentionally suppressing information (updating task). However, when the task required unintentional inhibition of competing items (retrieval-practice task), this developmental trend was not found and children and adults showed similar levels of retrieval-induced forgetting. The results are discussed in terms of the development of efficient inhibition and the distinction between intentional and unintentional inhibitions.