Biomedical subjects

Denise C Park

Publications and source records attributed to Denise C Park.

At least 19 recordsLinked to original sources

PubMed2006

fMRI environment can impair memory performance in young and elderly adults.

The influence of the fMRI (functional magnetic resonance imaging) scanning environment on working memory and long-term memory performance was investigated. We predicted that performance would be impaired on memory tasks in the distracting fMRI environment relative to laboratory performance. Results indicated that both young and old adults showed performance decrements in the scanning environment compared to the laboratory for a long-term memory task, but not for a passive working memory task, consistent with the idea that divided attention costs occur for more difficult tasks. In addition, elderly adults were disproportionately impaired by the scanning environment on the long-term memory task, congruent with the finding that divided attention costs at encoding are larger for older than younger adults. The findings suggest that performance may be changed by the scanning environment and that, in some circumstances, the fMRI environment may have a disproportionate effect on cognitive performance of older adults.

Adult↗

PubMed2006

Decreased neural specialization in old adults on a working memory task.

Compelling evidence shows that there is decreased neural specialization in the ventral visual cortex in older adults under passive viewing conditions. We assessed whether such specialization would be maintained on a working memory task and whether decreased specialization co-occurred with increased prefrontal activations. Participants encoded three faces or houses and maintained the set across an 8-s interval. Results provided evidence for less specialization of faces and houses in older adults than in younger adults, while the middle and inferior frontal cortex showed increased activation in elders compared with the young.

Adolescent↗

PubMed2006

Source memory, aging and culture.

BACKGROUND: The present study investigates the possibility that culture affects age differences in context memory. There is evidence that East-Asians process scenes more holistically and show better context memory than Americans. OBJECTIVE: We examined evidence for differences in binding source to context in young and old Americans and native Chinese. We hypothesized that age effects on source memory could be mitigated due to these cultural differences in processing style. METHODS: During incidental encoding, younger and older Chinese and Americans watched a video with statements spoken by four distinct speakers. After a brief interval, participants identified source (experiment 1) or item and source (experiment 2). RESULTS: We observed substantial age-related deficits in source memory in both cultures but little evidence for cultural differences in source or item memory. CONCLUSION: Basic source memory processes operate similarly across culture and age. The source of holistic processing differences observed between cultures may occur in cognitive operations that are more highly bound to a social context.

Adult↗

PubMed2006

Categorical organization in free recall across culture and age.

BACKGROUND: Cross-cultural differences in cognition suggest that Westerners use categories more than Easterners, but these differences have only been investigated in young adults. OBJECTIVE: The contributions of cognitive resource and the extent of cultural exposure are explored for free recall by investigating cross-cultural differences in categorical organization in younger and older adults. Cultural differences in the use of categories should be larger for elderly than young because categorization is a well-practiced strategy for Westerners, but age-related cognitive resource limitations may make the strategy difficult for elderly Easterners to implement. Therefore, we expect that cultural differences in categorization will be magnified in elderly adults relative to younger adults, with Americans categorizing more than Chinese. METHODS: Across two studies, 112 young and 112 elderly drawn from two cultures (American and Chinese) encoded words presented in their native language. One word list contained categorically-unrelated words and the other, categorically-related words; both lists were presented in the participants' native language. In experiment 1, the words were strong category associates, and in experiment 2, the words were weak category associates. Participants recalled all the words they could remember, and the number of words recalled and degree of clustering by category were analyzed. RESULTS: As predicted, cultural differences emerged for the elderly, with East-Asians using categories less than Americans during recall of highly-associated category exemplars (experiment 1). For recall of low-associate exemplars, East-Asians overall categorized less than Americans (experiment 2). Surprisingly, these differences in the use of categories did not lead to cultural differences in the number of words recalled. The expected effects of age were apparent with elderly recalling less than young, but in contrast to previous studies, elderly also categorized less than young. CONCLUSION: These studies provide support for the notion that cultural differences in categorical organization are larger for elderly adults than young, although culture did not impact the amount recalled. These data suggest that culture and age interact to influence cognition.

Adolescent↗

PubMed2006

Age-related stereotypes: a comparison of American and Chinese cultures.

BACKGROUND: It is commonly assumed that age-related stereotypes are more positive in East Asian cultures compared to Western cultures. However, research conducted in Western cultures has demonstrated that age-related stereotypes are multidimensional and their valence is content-dependent. OBJECTIVE: In this study we investigated stereotypes about young and old adults, held by both young and old in the US and in China by focusing on the valence of age stereotypes across two content domains: social/emotional and mental/physical. The goal was to identify whether there were any cultural differences in age-related stereotypes in Chinese and American cultures. METHODS: Both young and old Chinese and American participants were asked to describe typical young and typical old people. All responses were then coded for valence (positive/negative/neutral) and for content (mental/physical, social/emotional, other). Descriptors about young and old people were initially analyzed separately; then data were integrated to examine group tendencies to be more positive or negative for each target age group. RESULTS: In both cultures, stereotypes reflected a shift from more positive to increasingly negative views of mental and physical traits as a function of aging. In social and emotional domains, stereotypes regarding old and young adults were relatively neutral, except for a small positive bias found among the young Chinese adults for both target age groups. CONCLUSION: Our results indicate that age-related beliefs regarding typical older adults are similar across East-Asian and Western cultures and that a global positive bias for old age in East-Asia is absent.

Adolescent↗

PubMed2006

Cultural differences in neural function associated with object processing.

Behavioral research suggests that Westerners focus more on objects, whereas East Asians attend more to relationships and contexts. We evaluated the neural basis for these cultural differences in an event-related fMRI study. East Asian and American participants incidentally encoded pictures of (1) a target object alone, (2) a background scene with no discernable target object, and (3) a distinct target object against a meaningful background. Americans, relative to East Asians, activated more regions implicated in object processing, including bilateral middle temporal gyrus, left superior parietal/angular gyrus, and right superior temporal/supramarginal gyrus. In contrast to the cultural differences in object-processing areas, few differences emerged in background-processing regions. These results suggest that cultural experiences subtly direct neuralactivity, particularly for focal objects, at an early stage of scene encoding.

Adolescent↗

PubMed2005

Memory beliefs and function in fibromyalgia patients.

OBJECTIVE: The aim of this study was to investigate memory beliefs and their relationship to actual memory function in fibromyalgia (FM) patients. METHODS: Twenty-three FM patients, 23 age- and education-matched controls, and 22 older controls completed the Metamemory in Adulthood (MIA) questionnaire, which assessed beliefs about seven aspects of memory function. Group differences on the seven scales were assessed, and scores on the capacity scale were correlated with objective memory performance. RESULTS: FM patients reported lower memory capacity and more memory deterioration than did either control group. Patients reported lower control or self-efficacy over memory, higher achievement motivation, higher strategy use, and higher anxiety about memory than age-matched controls did. Among the patients, perceived capacity, achievement motivation, and self-efficacy were significantly correlated with objective memory performance on a recall task. CONCLUSION: FM patients' complaints about memory function have some accuracy.

Achievement↗

PubMed2005

Contributions of processing ability and knowledge to verbal memory tasks across the adult life-span.

This study investigated the relationships of processing capacity and knowledge to memory measures that varied in retrieval difficulty and reliance on verbal knowledge in an adult life-span sample (N = 341). It was hypothesized that processing ability (speed and working memory) would have the strongest relationship to tasks requiring active retrieval and that knowledge (vocabulary ability) would be related to verbal fluency and cued recall, as participants relied upon verbal knowledge to retrieve category items (fluency) or develop associations (cued recall). Measurement and structural equation models were developed for the entire sample and separately for younger (aged 20-54 years, n = 168) and older (aged 55-92 years, n = 173) subgroups. In accordance with the hypotheses, processing ability was found to be most highly related to free recall, with additional significant relationships to cued recall, verbal fluency, and recognition. Knowledge was found to be significantly related only to verbal fluency and to cued recall. Moreover, knowledge was more important for older than for younger adults in mediating variance in cued recall, suggesting that older adults may use age-related increases in knowledge to partially compensate for processing declines when environmental support is available in memory tasks.

Adult↗

PubMed2005

Aging and the neural correlates of successful picture encoding: frontal activations compensate for decreased medial-temporal activity.

We investigated the hypothesis that increased prefrontal activations in older adults are compensatory for decreases in medial-temporal activations that occur with age. Because scene encoding engages both hippocampal and prefrontal sites, we examined incidental encoding of scenes by 14 young and 13 older adults in a subsequent memory paradigm using functional magnetic resonance imaging (fMRI). Behavioral results indicated that there were equivalent numbers of remembered and forgotten items, which did not vary as a function of age. In an fMRI analysis subtracting forgotten items from remembered items, younger and older adults both activated inferior frontal and lateral occipital regions bilaterally; however, older adults showed less activation than young adults in the left and right parahippocampus and more activation than young adults in the middle frontal cortex. Moreover, correlations between inferior frontal and parahippocampal activity were significantly negative for old but not young, suggesting that those older adults who showed the least engagement of the parahippocampus activated inferior frontal areas the most. Because the analyses included only the unique activations associated with remembered items, these data suggest that prefrontal regions could serve a compensatory role for declines in medial-temporal activations with age.

Adult↗

PubMed2004

Aging reduces neural specialization in ventral visual cortex.

The present study investigated whether neural structures become less functionally differentiated and specialized with age. We studied ventral visual cortex, an area of the brain that responds selectively to visual categories (faces, places, and words) in young adults, and that shows little atrophy with age. Functional MRI was used to estimate neural activity in this cortical area, while young and old adults viewed faces, houses, pseudowords, and chairs. The results demonstrated significantly less neural specialization for these stimulus categories in older adults across a range of analyses.

Adult↗

PubMed2004

Aging and medical adherence: the use of automatic processes to achieve effortful things.

This research examined whether forming detailed implementation plans for achieving a goal improved older adults' adherence to a health behavior. Nondiabetic participants (N = 31) rehearsed, deliberated, or formed implementation intentions to perform home blood glucose monitoring, 4 times daily for 3 weeks. The implementation group performed tests nearly 50% more often than the 2 comparison groups. Results were not attributable to a priori differences in intentions to perform testing. Findings indicate that implementation intentions can facilitate older adults' performance of important medical self-care tasks in naturalistic settings over sustained periods of time and concur with previous research that implicates automatic cognitive processes that do not show age-related decline. These results support the utility of this technique for improving adherence to health behaviors in clinical populations.

Aged↗

PubMed2004

Category norms as a function of culture and age: comparisons of item responses to 105 categories by american and chinese adults.

Understanding how aging influences cognition across different cultures has been hindered by a lack of standardized, cross-referenced verbal stimuli. This study introduces a database of such item-level stimuli for both younger and older adults, in China and the United States, and makes 3 distinct contributions. First, the authors specify which item categories generalize across age and/or cultural groups, rigorously quantifying differences among them. Second, they introduce novel, powerful methods to measure between-group differences in freely generated ranked data, the rank-ordered logit model and Hellinger Affinity. Finally, a broad archive of tested, cross-linguistic stimuli is now freely available to researchers: data, similarity measures, and all stimulus materials for 105 categories and 4 culture-by-age groups, comprising over 10,000 fully translated unique item responses.

Adolescent↗

PubMed2004

A lifespan database of adult facial stimuli.

Faces constitute a unique and widely used category of stimuli. In spite of their importance, there are few collections of faces for use in research, none of which adequately represent the different ages of faces across the lifespan. This lack of a range of ages has limited the majority of researchers to using predominantly young faces as stimuli even when their hypotheses concern both young and old participants. We describe a database of 575 individual faces ranging from ages 18 to 93. Our database was developed to be more representative of age groups across the lifespan, with a special emphasis on recruiting older adults. The resulting database has faces of 218 adults age 18-29, 76 adults age 30-49, 123 adults age 50-69, and 158 adults age 70 and older. These faces may be acquired for research purposes from http://agingmind.cns.uiuc.edu/facedb/. This will allow researchers interested in using facial stimuli access to a wider age range of adult faces than has previously been available.

Adolescent↗

PubMed2004

A cross-culturally standardized set of pictures for younger and older adults: American and Chinese norms for name agreement, concept agreement, and familiarity.

The present study presents normative measures for 260 line drawings of everyday objects, found in Snodgrass and Vanderwart (1980), viewed by individuals in China and the United States. Within each cultural group, name agreement, concept agreement, and familiarity measures were obtained separately for younger adults and older adults. For a subset of 57 pictures (22%), there was equivalence in both name agreement and concept agreement, and for an additional subset of 29 pictures (11%), there was nonequivalent name agreement but equivalent concept agreement, across all culture-by-age groups. The data indicate substantial differences across culture-by-age groups in name agreement percentages and number of distinct name responses provided. We discovered significant differences between older and younger American adults in both name agreement percentages (67 pictures, or 26%) and concept agreement percentages (44 pictures, or 17%). Written naming responses collected for the entire set of Snodgrass and Vanderwart pictures showed shifts in both naming and concept agreement percentages over the intervening decades: Although correlations in name agreement were strong (r = .71, p < .001) between our younger American samples and those of Snodgrass and Vanderwart, name agreement percentages have changed for a substantial proportion (33%) of the 260 pictures; moreover, 63% of the stimuli for which Snodgrass and Vanderwart reported concept agreement now appear to differ. We provide comprehensive comparison statistics and tests for both the present study and prior ones, finding differences across numerous item-level measures. The corpus of data suggests that substantial differences in all measures can be found across age as well as culture, so that unequivocal conclusions with respect to cross-cultural or age-related differences in cognition can be made only when appropriate stimuli are selected for studies. Data for all 260 pictures, for each of the four groups, and all supporting materials and tests are freely archived at http://agingmind.cns.uiuc.edu/Pict_Norms. The full set of these norms may be downloaded from www.psychonomic.org/archive/.

Adolescent↗

PubMed2003

Working memory for complex scenes: age differences in frontal and hippocampal activations.

Age differences in frontal and hippocampal activations in working memory were investigated during a maintenance and subsequent probe interval in an event-related fMRI design. Younger and older adults either viewed or maintained photographs of real-world scenes (extended visual or maintenance conditions) over a 4-sec interval before responding to a probe fragment from the studied picture. Behavioral accuracy was largely equivalent across age and conditions on the probe task, but underlying neural activations differed. Younger but not older adults showed increased left anterior hippocampal activations in the extended visual compared with the maintenance condition. On the subsequent probe interval, however, older adults showed more left and right inferior frontal activations than younger adults. The increased frontal activations at probe in older adults may have been compensatory for the decreased hippocampal activations during maintenance, but alternatively could have reflected the increased difficulty of the probe task for the older subjects. Thus, we demonstrate qualitatively different engagement of both frontal and hippocampal structures in older adults in a working memory task, despite behavioral equivalence.

Adult↗

PubMed2003

The Martin and Park Environmental Demands (MPED) Questionnaire: psychometric properties of a brief instrument to measure self-reported environmental demands.

BACKGROUND AND AIMS: The present study examines the usefulness of a newly developed instrument, the Martin and Park Environmental Demands (MPED) Questionnaire, to measure the level of self-reported environmental demands of day-to-day events faced by adults aged 35 to 84 years, particularly as these demands influence forgetfulness in taking medications. METHODS: The MPED has two scales including Busyness, which addresses the density or pace of daily events to which an individual attends; and Routine, addressing the predictability or routinization of events independent of density. The MPED was administered to a sample of 121 rheumatoid arthritis patients, along with a baseline assessment battery measuring age, education, employment status, household size and other factors that might influence self-perception of Busyness and Routine. RESULTS: The scale showed good internal consistency and external validity. Higher levels of environmental demand were negatively correlated with age and positively correlated with employment, household size and medication-taking errors. There was a significant independent association between Busyness and adherence errors even after controlling for the effects of these sociodemographic variables. CONCLUSIONS: The MPED is recommended when trying to assess the general daily level of environmental demands.

Adult↗

PubMed2003

Contributions of source and inhibitory mechanisms to age-related retroactive interference in verbal working memory.

Determining contributions of source-monitoring and inhibitory function to age-related forgetting has been an elusive goal for cognitive theorists. Five studies used a verbal working memory paradigm to examine mechanisms accounting for disproportionate retroactive interference (RI) experienced with adult aging. Participants distinguished studied target-word pairs from interfering pairs that were read aloud. Source-monitoring and inhibitory task components varied through manipulations of response requirements. RI effects were primarily due to source-monitoring failures rather than to inhibitory failures. Removing both source and inhibitory components eliminated age differences in RI. When source monitoring was emphasized, RI continued to be observed in all age groups but disproportionately for older adults. Process dissociation analyses of memory found recollection decreases and familiarity increases consistent with source failures.

Adult↗

PubMed2003

Theoretical models of cognitive aging and implications for translational research in medicine.

PURPOSE: We provide an overview of theoretical models of cognitive aging and present empirical research that uses these models to explain older patients' medical behaviors and to develop interventions for improving the delivery of health information and services to older adults. DESIGN AND METHODS: Theoretical accounts of age and cognition are summarized and are related to key research findings, including age differences in comprehension of medical information, adherence, and use of medical technologies. The implications of cognitive aging theories for designing optimal medical environments and enhancing adherence are discussed. RESULTS: Age declines in basic cognitive abilities such as working memory capacity limit older adults' ability to comprehend and recall several types of novel medical information. In contrast, automatic processes and environmental cues can benefit older adults, as shown by age increases in compliance for practiced or mentally imaged health behaviors, but can also be dangerous, as shown by older adults' greater belief in false but familiar health statements. Last, cognitive aging is shown to be a useful model for investigating cognitive disorders. IMPLICATIONS: Cognitive aging theories are important for understanding older patient behaviors and suggest age-related declines as well as gains in performance in medical domains. In addition, models of cognitive aging are useful in guiding the development of interventions that improve health care in older patients and in furthering our understanding of cognitive dysfunction in populations other than older adults.

Aged↗