Age-related changes in odor discrimination

Odor naming and recognition memory are poorer in children than in adults. This study explored whether such differences might result from poorer discriminative ability. Experiment 1 used an oddity test of discrimination with familiar odors on 6-year-olds, 11-year-olds, and adults. Six-year-olds were significantly poorer at discrimination relative to 11-year-olds and adults, who did not differ. Experiment 2 used the same procedure but with hard-to-name visual stimuli and compared only 6-year-olds with adults (as with the remaining experiments in this study). There was no difference in performance between these groups. Experiment 3 used the same procedure as Experiment 1 but with less familiar odors. Six-year-olds were significantly poorer at discrimination than adults. In Experiment 4 the researchers controlled for verbal labeling by using an articulatory suppression task, with the same basic procedure as in Experiment 1. Six-year-old performance was the same as for Experiment 1 and significantly poorer than that of adults. Impoverished olfactory discrimination may underpin performance deficits previously observed in children. These all may result from their lesser experience with odors, relative to adults.     

Age-related differences in the impact of spacing, lag, and retention interval

An experiment is reported that examines age-related differences in the lag effect and its relation to retention interval. A total of 30 young and 30 older adults received both once-presented pairs and twice-presented pairs that were tested in a continuous cued-recall paradigm either after a short retention interval (2 pairs intervening between the last presentation of a pair and its test) or a long retention interval (20 pairs intervening between the last presentation of a pair and its test). In addition, the twice-presented pairs were separated by either 0, 1, 4, 8, or 20 intervening pairs. The results replicated the interaction between retention interval and lag that has been reported by Glenberg (1976, Journal of Verbal Learning and Verbal Behavior, 15, 1-16). Furthermore, although the older adults performed considerably lower than the younger adults in overall recall performance, their data were remarkably similar to the younger adults in the patterning of means. A mathematical modeling procedure was used to fit the data to Estes' stimulus fluctuation model. The results of this modeling procedure suggest that, compared with younger adults, older adults (a) encode less contextual information at a given point in time and (b) have a slower rate of contextual fluctuation across time.     

Age-related differences in deception

Young and older participants judged the veracity of young and older speakers' opinions about topical issues. All participants found it easier to judge when an older adult was lying relative to a young adult, and older adults were worse than young adults at telling when speakers were telling the truth versus lying. Neither young nor older adults were advantaged when judging a speaker from the same age group. Overall, older adults were more transparent as liars and were worse at detecting lies, with older adults' worse emotion recognition fully mediating the relation between age group and lie detection failures.     

Age-related differences in irrelevant-speech effects

Three experiments examined age-related differences in irrelevant-speech effects. Younger and older adults were required to recall short prose texts or lists of semantically related words presented visually together with distractor speech. In all experiments, older adults made more semantically related intrusion errors from the irrelevant speech than younger adults. Results of a source memory test suggested that these age-related differences in interference are most likely due to both inhibitory deficits and source-monitoring problems. The results lend partial support to the inhibition deficit theory of cognitive aging.     

Proactive inhibition in short-term retention

Summary A model of Estes which describes retroactive inhibition effects was adapted to the process of proactive inhibition in short-term retention. Results obtained by Reutener (1972) with the single-item free recall paradigm could be adequately described with the proposed model.     

Age-related changes in children's hedonic response to male body odor

Male sweat smells disgusting to many adults, but it is unclear whether children find it so. In Experiment 1A, children (mean age = 8.7 years) and adolescents (M=16.6 years) smelled male sweat and other odors, rated each for liking, and attempted their identification. Only female adolescents disliked male sweat and could identify it. Experiment 1B, using the same procedure, obtained this gender difference in adults (M=26.7 years). In Experiment 2, children (M=8.1 years) and adolescents (M=16.6 years) were cued about the identity of the same odors. Irrespective of gender, adolescents disliked male sweat more than did children. In sum, dislike for the odor of male sweat may be an acquired social response that is based on odor identification.     

Age-related differences in inference revision processing

In comparison to younger adults, older adults demonstrate deficiencies in cognitive and linguistic abilities. Such cognitive factors that decline with age include working memory capacity and inhibitory abilities. The purpose of the present investigation was to measure differences in time course processing of inference revision abilities, as well as working memory, as they exist relative to adult age differences. Fifteen neurologically intact older adults and 15 younger adults participated in this study. A cross-modal lexical priming paradigm was chosen as the measure of the inference revision task; the listening span task of Tompkins, Bloise, Timko, and Baumgaertner (1994) was selected as the measure of working memory. Both groups demonstrated normal priming effects. No age-related differences were found on the working memory measure. Age-related differences did emerge on inferencing abilities. A significant correlation emerged between the older group's performance on comprehending inference revisions and their working memory capacity. Generally, inhibitory abilities and working memory capacity appeared to adversely affect older participant's performance.     

Age-related differences in localized attentional interference

Attentional selection of an object in the visual field degrades processing of neighboring stimuli in young adults. A pair of experiments examined the effects of aging on such localized attentional interference. In Experiment 1, younger and older observers made speeded same-different judgments of target shapes that varied in spatial separation. Performance declined for both age groups as the distance between targets decreased, but an Age x Distance interaction indicated that the magnitude of this effect was larger for older adults. Experiment 2 ruled out sensory masking as an explanation for these findings. Results indicate that older observers experience losses in the ability to attend to multiple spatially proximal stimuli within the visual field.     

Age-related differences in timing with breaks

Two groups of participants differing in age were compared on a time production task during which timing was temporarily interrupted. Produced intervals lengthened with increasing delay before the break occurrence, and the effect was more pronounced in older than in younger adults. A reaction time response to the signal beginning the break period was required also. Older participants responded more slowly to this signal, but they benefited to a greater extent from a lengthening of the time preceding its presentation. These results suggest that performance of older participants is affected by attention sharing and preparation involved in timing with breaks.     

Age-related differences in profiles of mood-change trajectories

As a group, older adults report positive affective lives. The extent to which there are subgroups of older adults whose moods are less positive, however, is unclear. Our aim in the present study was to identify and characterize different subgroups of adults who exhibit distinct trajectories of mood change across a relatively short time period. Seventy-nine young and 103 older adults continuously reported their moods while viewing emotional and neutral faces. Cluster analysis revealed four subgroups of mood-change trajectories. Both the most positive and the most negative subgroups included more older than young adults (ps < .05), suggesting that not all older adults exhibit higher positive affect than young adults. Analyses of variance revealed that the most negative group exhibited slower processing speed, more state anxiety and neuroticism, and looked less at happy faces than the other groups (ps < .05). The results are discussed from an adult developmental perspective, focusing on the increased variability of mood trajectories in the older adults and whether this is a reflection of adaptive functioning or a potential harbinger of dysfunction.     

The co-ordination of codes in short-term retention

The present experiments explored ways in which information encoded along different dimensions might be co-ordinated to determine memory performance. First, can an acoustic similarity decrement be offset by additional semantic encoding? Experiment I offers evidence for this compensatory interaction of codes. Second, does trade-off occur such that more information held in one code means less in another code? Third, are codes additive? Experiment II offers no support for the notion of a trade-off between encoding systems. However, when two codes were made available in the second study, recall was increased over the level achieved by either code alone.     

Interindividual differences in acuity for odor and aroma

To determine the olfactory acuity of 27 subjects a sensory test was presented which was divided into 4 subtests, 2 for nasal and 2 for oral stimulation. Each subtest contained 28 (4 substances X 7 concentrations) olfactory detection tasks (items). The substances used were lemon and rum aroma as well as ethyl butyrate and amyl acetate, the solvents tap water and sugared tap water. Analysis showed that the test provided a clear differentiation between subjects of low, medium, and high olfactory acuity. The intercorrelations among the test substances and the split-half reliabilities of the subtests proved relatively high, whereas only moderate to low intercorrelations among the subtests were found. This was considered an effect of intraindividual variations of olfactory sensitivity. Finally, some conclusions for the construction of acuity tests for odor and aroma are presented.     

Intra-list differences in short-term memory

Subjects attempted to recall lists of nine consonants immediately after presentation. Using various recall orders it was found that recall of part of a list interfered with retention of the other parts, memory for items presented early in a list being less affected by such interference than was that for later items. Since this result was not obtained when rate of presentation was increased, it is suggested that rehearsal contributed to the greater stability of early items.     

Age-related differences and similarities in dual-task interference

Differences between younger adults (mean age, 20.7 years) and older adults (mean age, 72.7 years) in dual-task performance were examined in 7 experiments in which the overlap between 2 simple tasks was systematically varied. The results were better fit by a task-switching model in which age was assumed to produce generalized slowing than by a shared-capacity model in which age was assumed to reduce processing resources. The functional architecture of task processing appears the same in younger and older adults. There was no evidence for a specific impairment in the ability of older adults to manage simultaneous tasks. There was evidence for both input and output interference, which may be greater in older adults.     

Age-related differences in episodic feeling-of-knowing arise from differences in memory performance

Previous studies about the effects of ageing on the episodic feeling-of-knowing (FOK) accuracy and its underlying processes have yielded conflicting results. Recent work suggests that using alternative measures to gamma correlations might allow more accurate and informative interpretations of metamemory performance in ageing. We therefore investigated this issue with a large sample of 59 young and 61 older participants using alternative signal-detection theory (SDT) measures. These measures (receiver operating characteristic curves and Brier score) are recommended in the literature and able to reveal the characteristic profile of impairment in ageing. Our results suggest that the FOK accuracy deficit observed in the literature arises from differences in memory performance. This observation provides a convenient explanation to the previous discrepancies and furthermore supports the interest of the use of SDT-derived measures in the frame of metamemory.