Search

How rapidly can we encode the specifics versus the gist of episodic memories? Competing theories have opposing answers, but empirical tests are based primarily on tasks of item memory. Few studies have addressed this question with tasks measuring the binding of event components (e.g., a person and a location), which forms the core of episodic memory. None of these prior studies included older adults, whose episodic memories are less specific in nature. We addressed this critical gap by presenting face–scene pairs (e.g., an old man with a park) at various encoding presentation rates to 80 young (M = 21.83 years) and 86 older (M = 68.62 years) adults. Participants completed associative recognition tests featuring old/intact (e.g., the old man with the same park), similar (e.g., the old man with a different park), and unrelated (e.g., the old man with a kitchen) pairs. Multinomial-processing-tree model analyses revealed that young and older adults encoded each pair's gist representation more rapidly than its specific representation, supporting fuzzy-trace theory. No age-related differences in gist representations were obtained at any presentation rate, but older adults required more time to encode specific representations commensurate with those of younger adults. However, older adults' abilities to retrieve these representations were cue-dependent, as they were more susceptible than younger adults to experiencing vivid false memories of similar lures. These phantom recollections were remediated with further increases in encoding time. Thus, slower speed of encoding partially underlies age-related declines in episodic memory specificity, but retrieval mechanisms also play a role. Public Significance Statement: The present study provides novel insights into the speed with which specific (detailed) and gist (meaning-based) representations of episodic memories can be encoded among young and older adults. These insights constrain leading theories of information processing and have implications for understanding why older adults are less likely to remember the specific details of past episodes. Providing older adults with more time to learn new information may be one solution for fostering stronger and longer-lasting memories that are rich in specific details. [ABSTRACT FROM AUTHOR]

The relation between an individual's memory accuracy and reported confidence in their memories can indicate self-awareness of memory strengths and weaknesses. We provide a lifespan perspective on this confidence-accuracy relation, based on two previously published experiments with 320 participants, including children aged 6-13, young adults aged 18-27, and older adults aged 65-77, across tests of working memory (WM) and long-term memory (LTM). Participants studied visual items in arrays of varying set sizes and completed item recognition tests featuring 6-point confidence ratings either immediately after studying each array (WM tests) or following a long period of study events (LTM tests). Confidence-accuracy characteristic analyses showed that accuracy improved with increasing confidence for all age groups and in both WM and LTM tests. These findings reflect a universal ability across the lifespan to use awareness of the strengths and limitations of one's memories to adjust reported confidence. Despite this age invariance in the confidence-accuracy relation, however, young children were more prone to high-confidence memory errors than other groups in tests of WM, whereas older adults were more susceptible to high-confidence false alarms in tests of LTM. Thus, although participants of all ages can assess when their memories are weaker or stronger, individuals with generally weaker memories are less adept at this confidence-accuracy calibration. Findings also speak to potential different sources of high-confidence memory errors for young children and older adults, relative to young adults. [ABSTRACT FROM AUTHOR]

There is considerable evidence that listeners’ understanding of a spoken sentence need not always follow from a full analysis of the words and syntax of the utterance. Rather, listeners may instead conduct a superficial analysis, sampling some words and using presumed plausibility to arrive at an understanding of the sentence meaning. Because this latter strategy occurs more often for sentences with complex syntax that place a heavier processing burden on the listener than sentences with simpler syntax, shallow processing may represent a resource conserving strategy reflected in reduced processing effort. This factor may be even more important for older adults who as a group are known to have more limited working memory resources. In the present experiment, 40 older adults (Mage = 75.5 years) and 20 younger adults (Mage = 20.7) were tested for comprehension of plausible and implausible sentences with a simpler subject-relative embedded clause structure or a more complex object-relative embedded clause structure. Dilation of the pupil of the eye was recorded as an index of processing effort. Results confirmed greater comprehension accuracy for plausible than implausible sentences, and for sentences with simpler than more complex syntax, with both effects amplified for the older adults. Analysis of peak pupil dilations for implausible sentences revealed a complex three-way interaction between age, syntactic complexity, and plausibility. Results are discussed in terms of models of sentence comprehension, and pupillometry as an index of intentional task engagement.

There is considerable evidence that listeners' understanding of a spoken sentence need not always follow from a full analysis of the words and syntax of the utterance. Rather, listeners may instead conduct a superficial analysis, sampling some words and using presumed plausibility to arrive at an understanding of the sentence meaning. Because this latter strategy occurs more often for sentences with complex syntax that place a heavier processing burden on the listener than sentences with simpler syntax, shallow processing may represent a resource conserving strategy reflected in reduced processing effort. This factor may be even more important for older adults who as a group are known to have more limited working memory resources. In the present experiment, 40 older adults (M age = 75.5 years) and 20 younger adults (M age = 20.7) were tested for comprehension of plausible and implausible sentences with a simpler subject-relative embedded clause structure or a more complex object-relative embedded clause structure. Dilation of the pupil of the eye was recorded as an index of processing effort. Results confirmed greater comprehension accuracy for plausible than implausible sentences, and for sentences with simpler than more complex syntax, with both effects amplified for the older adults. Analysis of peak pupil dilations for implausible sentences revealed a complex three-way interaction between age, syntactic complexity, and plausibility. Results are discussed in terms of models of sentence comprehension, and pupillometry as an index of intentional task engagement. [ABSTRACT FROM AUTHOR]

Reduced hearing acuity is among the most prevalent of chronic medical conditions among older adults. An experiment is reported in which comprehension of spoken sentences was tested for older adults with good hearing acuity or with a mild-to-moderate hearing loss, and young adults with age-normal hearing. Comprehension was measured by participants’ ability to determine of the agent of an action in sentences that expressed this relation with a syntactically less complex subject-relative construction or a syntactically more complex object-relative construction. Agency determination was further challenged by inserting a prepositional phrase into sentences between the person performing an action and the action being performed. As a control, prepositional phrases of equivalent length were also inserted into sentences in a non-disruptive position. Effects on sentence comprehension of age, hearing acuity, prepositional phrase placement and sound level of stimulus presentations appeared only for comprehension of sentences with the more syntactically complex object-relative structures. Working memory as tested by reading span scores accounted for a significant amount of the variance in comprehension accuracy. Once working memory capacity and hearing acuity were taken into account, chronological age among the older adults contributed no further variance to comprehension accuracy. Results are discussed in terms of the positive and negative effects of sensory-cognitive interactions in comprehension of spoken sentences and lend support to a framework in which domain-general executive resources, notably verbal working memory, play a role in both linguistic and perceptual processing.

A fundamental question in psycholinguistic theory is whether equivalent success in sentence comprehension may come about by different underlying operations. Of special interest is whether adult aging, especially when accompanied by reduced hearing acuity, may shift the balance of reliance on formal syntax vs. plausibility in determining sentence meaning. In two experiments participants were asked to identify the thematic roles in grammatical sentences that contained either plausible or implausible semantic relations. Comprehension of sentence meanings was indexed by the ability to correctly name the agent or the recipient of an action represented in the sentence. In Experiment 1 young and older adults' comprehension was tested for plausible and implausible sentences with the meaning expressed with either an active-declarative or a passive syntactic form. In Experiment 2 comprehension performance was examined for young adults with age-normal hearing, older adults with good hearing acuity, and age-matched older adults with mild-to-moderate hearing loss for plausible or implausible sentences with meaning expressed with either a subject-relative (SR) or an object-relative (OR) syntactic structure. Experiment 1 showed that the likelihood of interpreting a sentence according to its literal meaning was reduced when that meaning expressed an implausible relationship. Experiment 2 showed that this likelihood was further decreased for OR as compared to SR sentences, and especially so for older adults whose hearing impairment added to the perceptual challenge. Experiment 2 also showed that working memory capacity as measured with a letter-number sequencing task contributed to the likelihood that listeners would base their comprehension responses on the literal syntax even when this processing scheme yielded an implausible meaning. Taken together, the results of both experiments support the postulate that listeners may use more than a single uniform processing strategy for successful sentence comprehension, with the existence of these alternative solutions only revealed when literal syntax and plausibility do not coincide. [ABSTRACT FROM AUTHOR]

Reduced hearing acuity is among the most prevalent of chronic medical conditions among older adults. An experiment is reported in which comprehension of spoken sentences was tested for older adults with good hearing acuity or with a mild-tomoderate hearing loss, and young adults with age-normal hearing. Comprehension was measured by participants' ability to determine the agent of an action in sentences that expressed this relation with a syntactically less complex subject-relative construction or a syntactically more complex object-relative construction. Agency determination was further challenged by inserting a prepositional phrase into sentences between the person performing an action and the action being performed. As a control, prepositional phrases of equivalent length were also inserted into sentences in a non-disruptive position. Effects on sentence comprehension of age, hearing acuity, prepositional phrase placement and sound level of stimulus presentations appeared only for comprehension of sentences with the more syntactically complex objectrelative structures. Working memory as tested by reading span scores accounted for a significant amount of the variance in comprehension accuracy. Once working memory capacity and hearing acuity were taken into account, chronological age among the older adults contributed no further variance to comprehension accuracy. Results are discussed in terms of the positive and negative effects of sensory-cognitive interactions in comprehension of spoken sentences and lend support to a framework in which domain-general executive resources, notably verbal working memory, play a role in both linguistic and perceptual processing. [ABSTRACT FROM AUTHOR]

Blow flies (Diptera: Calliphoridae) are typically the first insects to arrive at human remains and carrion. Predictable succession patterns and known larval development of necrophagous insects on vertebrate remains can assist a forensic entomologist with estimates of a minimum post-mortem interval (PMImin) range. However, adult blow flies are infrequently used to estimate the PMImin, but rather are used for a confirmation of larval species identification. Cuticular hydrocarbons have demonstrated potential for estimating adult blow fly age, as hydrocarbons are present throughout blow fly development, from egg to adult, and are stable structures. The goal of this study was to identify hydrocarbon profiles associated with the adults of a North American native blow fly species, Cochliomyia macellaria (Fabricius) and a North American invasive species, Chrysomya rufifacies (Macquart). Flies were reared at a constant temperature (25°C), a photoperiod of 14:10 (L:D) (h), and were provided water, sugar and powdered milk ad libitum. Ten adult females from each species were collected at day 1, 5, 10, 20, and 30 post-emergence. Hydrocarbon compounds were extracted and then identified using gas chromatography-mass spectrometry (GC-MS) analysis. A total of 37 and 35 compounds were detected from C. macellaria and Ch. rufifacies, respectively. There were 24 and 23 n-alkene and methyl-branched alkane hydrocarbons from C. macellaria and Ch. rufifacies, respectively (10 compounds were shared between species), used for statistical analysis. Non-metric multidimensional scaling analysis and permutational multivariate analysis of variance were used to analyze the hydrocarbon profiles with significant differences (P<0.001) detected among post-emergence age cohorts for each species, and unique hydrocarbon profiles detected as each adult blow fly species aged. This work provides empirical data that serve as a foundation for future research into improving PMImin estimates made by forensic practitioners and potentially increase the use of adult insects during death investigations. [ABSTRACT FROM AUTHOR]

Bruner and Potter (1964) demonstrated the surprising finding that incrementally increasing the clarity of images until they were correctly recognized (ascending presentation) was less effective for recognition than presenting images in a single presentation at that same clarity level. This has been attributed to interference from incorrect perceptual hypotheses formed on the initial presentations under ascending conditions. We demonstrate an analogous effect for spoken word recognition in older adults, with the size of the effect predicted by working memory span. This effect did not appear for young adults, whose group spans exceeded that of the older adults. [ABSTRACT FROM AUTHOR]

Abstract: Older adults often perform poorly on Theory of Mind (ToM) tests that require understanding of others’ beliefs and intentions. The course and specificity of age changes in belief reasoning across the adult lifespan is unclear, as is the cause of the age effects. Cognitive and neuropsychological models predict that two types of processing might influence age differences in belief reasoning: executive functioning and social cue detection. In the current study we assessed 129 adults aged between 18 and 86 on novel measures of ToM (video clips and verbal vignettes), which manipulated whether true or false belief reasoning was required. On both video and verbal tasks, older adults (aged 65–88) had specific impairments in false belief reasoning, but showed no such problem in performing true belief tasks. Middle-aged adults (aged 40–64) generally performed as well as the younger adults (aged 18–39). Difficulties in updating information in working memory (but not inhibitory problems) partially mediated the age differences in false belief reasoning. Also, the ability to decode biological motion, indexing social cue detection, partially mediated age-related variance in the ability to interpret false beliefs. These results indicate that age differences in decoding social cues and updating information in memory may be important influences on the specific problems encountered when reasoning about false beliefs in old age. [Copyright &y& Elsevier]

Older adults often have more difficulty listening in challenging environments than their younger adult counterparts. On the one hand, auditory aging can exacerbate and/or masquerade as cognitive difficulties when auditory processing is stressed in challenging listening situations. On the other hand, an older listener can overcome some auditory processing difficulties by deploying compensatory cognitive processing, especially when there is supportive context. Supportive context may be provided by redundant cues in the external signal(s) and/or by internally stored knowledge about structures that are functionally significant in communication. It seems that listeners may achieve correct word identification in various ways depending on the challenges and supports available in complex auditory scenes. We will review evidence suggesting that older adults benefit as much or more than younger adults from supportive context at multiple levels where expectations or constraints may be related to redundancies in semantic, syntactic, lexical, phonological, or other sub-phonemic cues in the signal, and/or to expert knowledge of structures at these levels. [ABSTRACT FROM AUTHOR]

Abstract: The effects of age on repetition priming and how such differences were related to intentional learning and working memory status were examined. Fourteen older (age 65–75) and 14 younger (age 18–28) healthy adults performed a modified delayed match-to-sample task consisting of a target object held in mind followed by nine test objects. Sixty four-channel EEGs were recorded as participants indicated whether each test object was the same or different from the target object. Half of all target and distractor objects were intentionally studied prior to the task, and both target and distractor objects were repeatedly presented up to four times in each trial. Although both age groups showed repetition priming effects, speed increases due to repetition were more enhanced for elderly. ERP repetition effects for both younger and older adults were indexed via early (200–550) and late (550–850ms) components. The early repetition effect was affected by whether a distractor was previously studied or not for younger but not for older adults. In contrast, the late repetition effect was not affected by prior intentional learning, and a marginal age effect suggested that repetitions of distractors likely affected older and younger adults differently. These findings suggest that at least two distinguishable repetition mechanisms differentially affect adult aging. [Copyright &y& Elsevier]

A shared feature of contemporary feminism and critical gerontology has been an attempted rapprochement between inequality in terms of social structure and the experience of identity under oppressive social conditions. For gerontology, this has meant the structural and personal implications of ageing in an ageist society. Narrative and masquerade have both been used as metaphors to examine strategies deployed in the management of an ageing, gendered self. They allow, it is argued, a critical space to arise between hidden aspects of identity and appearances, but the way that these concepts have been handled varies significantly between social theorists. Both narrative and masquerade may hold the danger of becoming inward-looking, and thus solipsistic, ceasing to be part of an interactive, dialogical process and end up as fixed, yet ungrounded psychic positions. The implications for a critical approach that reaches beyond the academy are considerable, and the paper ends with a discussion of the possibilities for solidarity across narrative boundaries presented by adult ageing. [Copyright &y& Elsevier]