Patricia M. Simone

Selective attention in a reaching task : Effect of normal aging and Alzheimer's disease

This study examined the ability of young adults, older adults, and older adults suffering from Alzheimers disease (AD) to perform a selective reaching task. Normal aging did not increase interference caused by distractors. In contrast, patients with AD showed massively increased effects of distractor interference. AD patients showed a high probability of making responses to distractor items. The proportion of these incorrect responses was related to the inability to use inhibitory processes, which increased with the severity of AD. Responses to distractors occurred despite the fact that patients could discriminate targets and distractors and knew that their responses to distractors were in error. These data suggest that AD patients are impaired in their ability to inhibit incorrect responses.

Frailty, Leisure Activity and Functional Status in Older Adults: Relationship With Subjective Well Being

Older adults generally experience high levels of life satisfaction (e.g., Charles & Carstensen, 2010) and participation in leisure activities may mediate some of their overall well-being. Frailty associated with biological aging may be related to reduced leisure activity engagement and loss of social belonging that may diminish life satisfaction (Charles, 2011). This study examined differences in leisure activity engagement by frailty status, and then tested a model evaluating the link between functional status and subjective well-being in a sample of 95 community-dwelling older adults. Participants completed self-report questionnaires that assessed leisure activity participation, life satisfaction, frailty, and mood. Leisure activities were coded as either social (e.g., taking classes) or solitary (e.g., reading) and summed across to create two composite scores. Results indicated there was a strong relationship between functional status and subjective well-being in older adults. High frailty and low social leisure engagement was associated with reduced subjective well-being. Implications for future research and clinical applications are discussed.

Effect of a Defining Feature on Negative Priming Across the Life Span

Negative priming paradigms examine selective attention, and may be explained by inhibitory processes (e.g. Tipper, 1985). Our study examines inhibition in children (6-11 years), younger adults (18-22 years), and older adults (60-82 years). Younger adults show inhibition to the reported feature of a stimulus (location or identity) (Milliken, Tipper, & Weaver, 1994) and to the defining feature of a stimulus (identity or colour) (Simone, Carlisle, & McCormick, 1998). Neither children (Tipper, Bourque, Anderson, & Brehaut, 1989) nor older adults (Connelly & Hasher, 1993) have consistently shown significant inhibition to the reported feature of identity, suggesting developmentally impaired inhibitory processing. Our current study demonstrates that both inhibition of a defining feature of identity and a reported feature of location are stable across the life span.

The Role of Attention in a Spatial Memory Task in Alzheimer Disease Patients

Memory and attention are interrelated cognitive processes that most likely influence the functioning of each other, yet they are often difficult to distinguish in psychological experiments. Young, aged adults, and patients with Alzheimer disease (AD) were tested on a delay response task measuring spatial memory that also placed high demands on attentional resources. Aged adults performed as well as young, suggesting that neither attentional nor memory abilities were exceeded in either group. However, AD subjects were severely impaired on this task. Two further experiments with AD patients examined the relative contribution of attentional and memory deficits in the performance of this population. Both memory and attentional impairments were found; however, errors due to memory factors were more closely related to severity of disease as measured on the Folstein Mini-Mental State Examination than were errors of attentional origin. These studies demonstrate the necessity of accounting for attentional components in studies examining memory, especially in patients with AD.

Diminished But Not Forgotten: Effects of Aging on Magnitude of Spacing Effect Benefits

OBJECTIVES Age-related changes in memory performance are common in paired associate episodic memory tasks, although the deficit can be ameliorated with distributed practice. Benefits of learning episode spacing in older adults have been shown in single-session studies with spaced presentations of items followed by a test. This study examined the magnitude of the spacing effect benefit in older adults relative to younger adults when given a multiday spacing effect paradigm. METHOD We examined the impact of spacing gap (~15min vs. 24hr) in younger (N = 51, Mage = 19 years, SD = 0.6) and older (N = 54, Mage = 65 years, SD = 8.8) adults with a 10-day retention interval. RESULTS Spacing of learning episodes benefited both younger and older adults. There was an age-related difference in the magnitude of this benefit that has not been observed in earlier studies. DISCUSSION These results suggest that spacing benefited the long-term memory of older adults, however the effect was diminished and qualitatively different from that of younger adults.

Long-term memory, sleep, and the spacing effect.

Many studies have shown that memory is enhanced when study sessions are spaced apart rather than massed. This spacing effect has been shown to have a lasting benefit to long-term memory when the study phase session follows the encoding session by 24 hours. Using a spacing paradigm we examined the impact of sleep and spacing gaps on long-term declarative memory for Swahili–English word pairs by including four spacing delay gaps (massed, 12 hours same-day, 12 hours overnight, and 24 hours). Results showed that a 12-hour spacing gap that includes sleep promotes long-term memory retention similar to the 24-hour gap. The findings support the importance of sleep to the long-term benefit of the spacing effect.

Influence of Competing Distractors on Response Selection in Huntington's Disease and Parkinson's Disease

Current theories of the basal ganglia suggest a functional role in filtering stimuli that are competing for response selection. We hypothesised that damage to the basal ganglia, as occurs in Huntingtons disease (HD) and Parkinsons disease (PD), may alter the effects of distractors on this filtering process. Fourteen HD subjects, 16 PD subjects, and age-matched healthy controls performed an ignored repetition test of negative priming. Negative priming was defined as a significant time cost in responding to a target that shared features with the distractor from the previous trial. Results indicated that whereas healthy controls and PD subjects showed normal negative priming, HD subjects failed to show negative priming. The results indicate that disruption to cells in the neostriatum, but not necessarily to cells in the substantia nigra, may affect selective attention by altering the influence of distractor stimuli competing for action.

Student Demographics, Satisfaction and Cognitive Demand in Two Lifelong Learning Programs.

Leisure activity participation has been found to have a positive impact on our health and well-being (e.g., Rowe & Kahn, 1998), and interest in lifelong learning as a leisure time activity is rising. This study compared self-reported measures of demographics, life satisfaction, cognitive status, and mood states in adult populations (over 50 years old). These older adults were attending noncredit courses in two different adult education programs: an adult education center and a university setting. Students in the two programs differed in several demographic features (age, years of formal education, socioeconomic status, and satisfaction with life). While both groups reported the same level of cognitive functioning, adult education students found the classes more familiar yet more challenging. Students in both programs reported an improvement in mood at the end of the class compared to the beginning. This study suggests that demographic variables, such as years of formal education, socioeconomic status, and life satisfaction, may determine which lifelong learning program adults choose. Regardless of program choice, participation in noncredit lifelong learning programs improves the mood of adults and may provide longer term benefits to their overall health and well-being. Further research is needed to determine whether the degree of challenge (Salthouse, Merish, & Miles, 2002) or lack of familiarity (Park, Gutchess, Meade, & Stine-Morrow, 2007) with the material will influence whether participation in lifelong learning programs has a lasting impact on cognitive health.

Influence of Attended Repetition Trials on Negative Priming in Younger and Older Adults

A lengthened response time when a distractor becomes a target, called negative priming, is an undisputed phenomenon in selective attention, yet just what the underlying mechanism responsible for negative priming is has not been resolved. In this study, the proportion of attended repetition trials was manipulated in order to test the predictions of three theories that have been proposed for explaining spatial negative priming: distractor suppression (e.g., Tipper, 1985), episodic memory retrieval (e.g., Neill, Valdes, & Terry, 1995), and novelty bias (e.g., Milliken, Tipper, Houghton, & Lupiáñez, 2000). The results supported the proposal that a novelty bias, which is flexible and can be overridden, is the primary mechanism responsible for priming in spatial tasks. Memory retrieval obscured the novelty bias for target processing, was more selective in older adults, and did not affect distractor processing. Novelty bias and distractor suppression may share the same inhibitory attentional mechanism.

Within-session spacing improves delayed recall in children

Multiple retrievals of a memory over a spaced manner improve long-term memory performance in infants, children, younger and older adults; however, few studies have examined spacing effects with young school-age children. To expand the understanding of the spacing benefit in children, the current study presented weakly associated English word-pairs to children aged 7–11 and cued their recall two times immediately (massed), after a delay of 5 or 10 items (spaced) or not at all (control). After this encoding session with or without two retrievals, participants were tested two times for memory of all word-pairs: immediately and 30 minutes after the encoding session. Multiple retrievals significantly improved memory on the tests. However, words repeated in a spaced design were remembered at higher rates than those that were massed, while gap size between repetitions (5 or 10) did not differentially impact performance. The data show that a within-session spacing strategy can benefit childrens ability to remember word-pairs after 30 minutes. Thus, asking students to recall what they have learned within a lesson is a technique that can be used in a classroom to improve long-term recall.