Effects of age and anxiety on episodic memory: selectivity and variability

Selective age-related differences in source memory relative to item memory, and individual differences in memory performance in relation to anxiety were explored with high- and low-anxious subjects screened from normal young and elderly adults. They were read false facts about the locations of well-known and unknown sights in a male or female voice. Intentional and incidental learning instructions were administered for source memory. Selective age-related deficits in source memory were observed under both encoding conditions. Higher level of anxiety was related to lower memory performance only in the old group; this relation was stronger in source recall. The findings suggest that the presence of such selectivity is unrelated to the tradeoff between item encoding and source encoding. Anxiety affects the variability, and mediates the selectivity of age effects on episodic memory.     

A neuropsychological study of fact memory and source amnesia

We investigated the ability of amnesic patients to learn new facts (e.g., Angel Falls is located in Venezuela) and also to remember where and when the facts were learned (i.e., source memory). To assess the susceptibility of fact and source memory to retrograde amnesia, patients prescribed electroconvulsive therapy were presented facts prior to the first treatment and were tested after their second treatment. All amnesic patients exhibited marked fact memory impairment. In addition, some amnesic patients exhibited source amnesia (i.e., they recalled a few facts but then could not remember where or when those facts had been learned). Source amnesia was unrelated to the severity of the memory deficit itself, because patients who exhibited source amnesia recalled as many facts as the patients who did not. These results show that the deficit in amnesia includes an impairment in acquiring and retaining new facts. Source amnesia can also occur, but it is dissociable from impaired recall and recognition and appears to reflect difficulty in remembering the specific context in which information is acquired. The findings are discussed in terms of their significance for how memory is organized.     

The Influence of Reminder Trials on Contextual Interference Effects

Two experiments investigated the proposition of the elaboration explanation for contextual interference that more than one task is present in working memory when multiple tasks are practiced in a random schedule but that only one task is present in working memory when multiple tasks are practiced in a blocked schedule. Three motor tasks were performed as fast as possible in either a random or blocked practice schedule. At the end of practice, a reminder trial for each task was either given or not given. Acquisition performance was slower for the random practice conditions than for the blocked practice conditions. Retention performance was faster for the random practice conditions than for the blocked practice condition that did not receive a reminder trial for each task. Importantly, performance differences were not found between the random practice conditions and the blocked practice condition that did receive a reminder trial for each task. A blocked practice condition with a beneficial acquisition and reminder task order pairing performed faster during both acquisition and retention than a comparable random practice condition. Reminder trials can facilitate detailing of task characteristics, and their effectiveness is determined by the elapsed time and number of intervening tasks during acquisition and retention.     

The influence of reminder trials on contextual interference effects

Two experiments investigated the proposition of the elaboration explanation for contextual interference that more than one task is present in working memory when multiple tasks are practiced in a random schedule but that only one task is present in working memory when multiple tasks are practiced in a blocked schedule. Three motor tasks were performed as fast as possible in either a random or blocked practice schedule. At the end of practice, a reminder trial for each task was either given or not given. Acquisition performance was slower for the random practice conditions than for the blocked practice conditions. Retention performance was faster for the random practice conditions than for the blocked practice condition that did not receive a reminder trial for each task. Importantly, performance differences were not found between the random practice conditions and the blocked practice condition that did receive a reminder trial for each task. A blocked practice condition with a beneficial acquisition and reminder task order pairing performed faster during both acquisition and retention than a comparable random practice condition. Reminder trials can facilitate detailing of task characteristics, and their effectiveness is determined by the elapsed time and number of intervening tasks during acquisition and retention.     

Contextual interference effects in sequence learning for young and older adults

Practice of different tasks in a random order induces better retention than practicing them in a blocked order, a phenomenon known as the contextual interference (CI) effect. Our purpose was to investigate whether the CI effect exists in sequence learning, such that practicing different sequences in a random order will result in better learning of sequences than practicing them in blocks, and whether this effect is affected by aging. Subjects practiced a serial reaction time task where a set of three 4-element sequences were arranged in blocks or in a random order on 2 successive days. Subjects were divided into 4 groups based on a 2-GROUP (young or old) by 2-ORDER (random or blocked practice) between-subject design. Three days after practice (Day 5), subjects were tested with practiced and novel sequences to evaluate sequence-specific learning. The results replicate the CI effect in sequence learning in both young and older adults. Older adults retained sequences better when trained in a random condition than in a blocked condition, although the random condition incurs greater task switching costs in older adults during practice. Our study underscores the distinction between age-related effects on learning vs. performance, and offers practical implications for enhancing skill learning in older adults.     

Developmental changes in source memory

Remembering how one learned a fact can be important in itself (e.g. for considering the value of information). However, source memory is also important, along with the temporal and perceptual information on which it is based, in giving memory an episodic or autobiographical quality. The present study investigated developmental changes in children’s ability to monitor source, in a paradigm adapted from Schacter, Harbluk and McLachlan (1984). This task, unlike previous source monitoring tasks used with children, has the potential to show the existence of a serious kind of source error called source amnesia. Children of 4, 6 and 8 years participated. They also completed measures believed to assess prefrontal function. Children showed a steady improvement with age in their ability to remember facts, but showed abrupt improvement between 4 and 6 years in their ability to monitor the source of those facts. Most notably, 4–year–old children displayed a great deal of source amnesia (i.e. errors of the kind committed by populations with frontal dysfunction), but 6– and 8–year–old children showed very few such errors. In addition, source memory was related, in some analyses although not in others, to behavioral measures often used to assess prefrontal functioning. The timing of the transition in source monitoring ability is discussed, including implications for childhood amnesia.     

Recognition and retrieval of proper names: Age differences in the fan effect

Abstract

A spreading activation model was applied, to explain. some aspects of retrieval failure for proper names. The fact that retrieval failures occur more frequently for well-known names than for unfamiliar names, and the increased incidence of name blocking in the elderly, are both interpreted in terms of the fan effect. Fanning is created when multiple far are known about a single person and results in slower and more error-prone retrieval, but the fan effect can be counteracted if the facts form an integrated set. Three groups of subjects—young, middle-aged, and elderly—learned sets of name-attribute statements in three conditions. In the no-fan condition, each name was uniquely paired with a single attribute; in the fan condition, each name was linked with three different attributes; in the crossed-fan condition, different names shared some of the same attributes. Verification RTs and cued recall responses showed that all subjects found the crossed-fan condition most difficult, but, when name-attribute links were not crossed, young and middle-aged subjects were able to counteract the fan effect by integrating the facts into a unified representation. Elderly subjects were less able to integrate effectively and were more susceptible to the fan effect.     

年龄、焦虑与情节记忆之内容与来源的关系

将情节记忆区分为内容记忆和来源记忆,筛选年老和年轻的高、低特质焦虑者完成记忆任务,以探讨情节记忆年老化的选择性和变异性及其与焦虑之间的联系。两项实验结果表明来源记忆是否随增龄而有选择性受损受来源性质影响,与来源呈现方式和来源识记意识性无关。焦虑干扰了老年组的记忆操作,是老年人情节记忆存在个体差异的原因之一;但焦虑对青年组没有不利影响,提示焦虑调节两类记忆的年龄差异。     

发散性思维的年龄差异及“位置法”记忆训练的作用

该研究的目的是探讨发散性思维的年龄差异以及“位置法”记忆训练对发散性思维的迁移作用。训练组为经过记忆训练的青年人24名,老年组20名,对照组为相匹配的青年人24名、老年人19名。结果表明:(1)在图形、符号、语义三方面的流畅性、变通性和独特性上,老年组均很显著地比青年组差。青年组的个别差异较大,老年组的更大,尤其是独特性。(2)青年训练组的图形流畅性、独特性及语义的独特性成绩显著优于其对照组,老年训练组图形的变通性有优于其对照组的趋势(P=.052),说明“位置法”记忆训练对发散性思维有一定的间接迁移作用,尤其是对青年人。(3)发散性思维与想象力、数字符号、训练前和训练后词的记忆以及图形的记忆成绩均有很显著正相关。而词汇成绩只与训练组两项发散性思维有显著相关。     

Skill learning in the elderly: diminished implicit and explicit memory for a motor sequence.

Explicit and implicit memory for a cognitive-motor sequence was studied in elderly and young adults. Implicit memory was examined in a serial reaction-time paradigm in which sequences of hand postures repeated cyclically, then shifted to random sequences. Two control groups received random sequences throughout. Movement times (MTs) across the first 4 blocks did not improve more in the elderly-repeated than in the elderly-random group. In contrast, the young-repeated group showed greater improvement in MT across these blocks than the young-random group. MT was less affected in the elderly than in the young by shifts between repeated and random sequences, indicating impaired implicit memory. Explicit memory, which was assessed by free recall and cued recall, also was impaired in the elderly. Diminished implicit memory in the elderly could not be explained solely by the possible intrusion of conscious recollection strategies.     

Effects of short-term retrieval on adult age differences in long-term recall of actions.

In Experiment 1 young and elderly subjects either recalled or repeated after every block of 4 actions, whereas control subjects received neither interpolated short-term recall nor action repetition. On a later long-term memory test, experimental subjects, regardless of age or condition, recalled slightly more actions than control subjects. In Experiment 2 young adult and elderly subjects received 12 short-term memory trials in which 2 actions were performed on each trial, but only 1 was cued for recall after a brief retention interval filled with a distracting activity. On a later long-term memory test for the actions performed on the short-term trials, both young and elderly subjects recalled significantly more previously cued than noncued actions. The Age X Cuing Condition interaction was negligible. Prior retrieval of actions appears to enhance later recall regardless of age but seemingly only when prior retrieval requires considerable cognitive effort (as in Experiment 2).     

Contextual information and memory for unfamiliar tunes in older and younger adults

We examined age differences in the effectiveness of multiple repetitions and providing associative facts on tune memory. For both tune and fact recognition, three presentations were beneficial. Age was irrelevant in fact recognition, but older adults were less successful than younger in tune recognition. The associative fact did not affect young adults' performance. Among older people, the neutral association harmed performance; the emotional fact mitigated performance back to baseline. Young adults seemed to rely solely on procedural memory, or repetition, to learn tunes. Older adults benefitted by using emotional associative information to counteract memory burdens imposed by neutral associative information.     

Demonstrating the Effects of Presentation Rate on Aging Memory Using the California Verbal Learning Test (CVLT)

Previous research has repeatedly found that the elderly demonstrate significant declines in direct measures of memory. This study examined verbal learning and memory in the young and old participants using the California Verbal Learning Test (CVLT). We hypothesized that slowing down the presentation rate of a list of words, therefore giving the participants more time to rehearse while learning new information, would decrease the normal differences found between the young and old adults on memory recall. However, at a faster presentation rate, the usual differences would be found. Participants took the CVLT, and correct recall responses were measured as a function of age and presentation rate. It was found, as expected, that at the faster presentation rate, the young did significantly better than the old on recall, but at the slower presentation rate, the differences between age groups diminished. It was concluded that by giving the elderly more time to rehearse information, age-related differences in memory recall could be greatly diminished.     

Cognitive addition: strategy choice and speed-of-processing differences in young and elderly adults

Sixty young and 60 elderly adults completed a pencil-and-paper addition test and solved 40 computer-presented simple addition problems. Strategies and problem solution times were recorded on a trial-by-trial basis and were classified in accordance with the distributions of associations model of strategy choices. The elderly group showed a performance advantage on the ability measure and for the developmental maturity of the mix of problem-solving strategies, but the young group showed an advantage for overall solution times. A componential analysis of the overall solution times for memory retrieval trials, however, showed no reliable age difference for rate of retrieving addition facts from long-term memory but did suggest that the elderly adults might have been slower than the younger adults for rate of encoding digits and verbally producing an answer. Overall results are interpreted within the context of the strategy choice model.     

Effect of distinctive encoding on false recognition,discrimination, and decision criteria in young and elderly adults

In order to examine the effects of distinctive encoding on age-related differences in false memory and decision criteria, we used a standard recognition paradigm and manipulated three encoding conditions: control, general, and distinctive. The results revealed main effects of age and encoding condition on hits and false recognition, and interactions between these variables, with elderly adults benefiting more than young adults from the encoding tasks. In the distinctive encoding condition, the age-related difference on false recognition was eliminated. These findings are discussed in terms of an age-related deficit in self-initiated distinctive processing. Further analyses showed that elderly adults used a more lenient decision criterion than young adults. Distinctive encoding led all subjects to use stringent decision criteria, but did not eliminate age differences.     

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.     

强大的错误记忆效应:词表呈现时间与呈现方式的影响

本研究采用DRM范式(Deese-Roediger-McDermott paradigm),考察了词表项目的呈现时间与呈现方式对错误记忆效应的影响。结果发现,被试对关键诱饵的错误再认受到学习阶段词表项目的呈现方式的影响,表现为所有项目随机呈现条件下的错误再认明显低于分组呈现条件,尤其是在20ms的随机呈现条件下,观察到了对关键诱饵的最低错误再认率。说明在对词表项目的编码阶段产生了对关键诱饵的连续激活,而对关键诱饵的错误记忆则是基于连续激活的不断累积的结果,当词表项目的随机呈现阻断了连续激活过程时,便会有效降低错误记忆效应。而且,在所有实验条件下均发现了错误记忆效应产生中所伴随的强烈主观体验,证实了错误记忆是一种强大的效应。