The effect of presentation rate on implicit sequence learning in aging

Implicit sequence learning is thought to be preserved in aging when the to-be learned associations are first-order; however, when associations are second-order, older adults (OAs) tend to experience deficits as compared to young adults (YAs). Two experiments were conducted using a first (Experiment 1) and second-order (Experiment 2) serial-reaction time task. Stimuli were presented at a constant rate of either 800 milliseconds (fast) or 1200 milliseconds (slow). Results indicate that both age groups learned first-order dependencies equally in both conditions. OAs and YAs also learned second-order dependencies, but the learning of lag-2 information was significantly impacted by the rate of presentation for both groups. OAs showed significant lag-2 learning in slow condition while YAs showed significant lag-2 learning in the fast condition. The sensitivity of implicit sequence learning to the rate of presentation supports the idea that OAs and YAs different processing speeds impact the ability to build complex associations across time and intervening events.     

Recognition of faces and complex objects in younger and older adults

We examined whether (1) age-associated impairments in face recognition are specific to faces or also apply to within-category recognition of other objects and (2) age-related face recognition deficits are related to impairments in encoding second-order relations and holistic information. In Experiments 1 and 2, we found reliable age differences for recognition of faces, but not of objects. Moreover, older adults (OAs) and younger adults (YAs) displayed similar face inversion effects. In Experiment 3, unlike YAs, OAs did not show the expected decline in performance for recognition of composites (Young, Hellawell, and Hay, 1987). In Experiment 4, both OAs and YAs showed a whole/part advantage (Tanaka and Farah, 1993). Our results suggest that OAs have spared function for processing of second-order relations and holistic information. Possible explanations for the finding that OAs have greater difficulty recognizing faces than recognizing other objects are proposed.     

Effortful semantic decision-making boosts memory performance in older adults

A major concern in age-related cognitive decline is episodic memory (EM). Previous studies indicate that both resource and binding deficits contribute to EM decline. Environmental support by task manipulations encouraging stronger cognitive effort and deeper levels of processing may facilitate compensation for these two deficits. To clarify factors that can counteract age-related EM decline, we assessed effects of cognitive effort (four levels) and level of processing (LoP, shallow/deep) during encoding on subsequent retrieval. Young (YAs, N?=?23) and older (OAs, N?=?23) adults performed two incidental encoding tasks, deep/semantic and shallow/perceptual. Cognitive effort was manipulated by varying decision-making demands. EM performance, indexed by d-prime, was later tested using a recognition task. Results showed that regardless of LoP, increased cognitive effort caused higher d-primes in both age groups. Compared to YAs, OAs showed a lower d-prime after shallow encoding across all cognitive effort levels, and after deep encoding with low cognitive effort. Deep encoding with higher levels of cognitive effort completely eliminated these age differences. Our findings support an environmental-compensatory account of cognitive ageing and can have important therapeutic implications.     

Agreement processing and attraction errors in aging: evidence from subject-verb agreement in German

Effects of aging on lexical processing are well attested, but the picture is less clear for grammatical processing. Where age differences emerge, these are usually ascribed to working-memory (WM) decline. Previous studies on the influence of WM on agreement computation have yielded inconclusive results, and work on aging and subject-verb agreement processing is lacking. In two experiments (Experiment 1: timed grammaticality judgment, Experiment 2: self-paced reading + WM test), we investigated older (OA) and younger (YA) adults’ susceptibility to agreement attraction errors. We found longer reading latencies and judgment reaction times (RTs) for OAs. Further, OAs, particularly those with low WM scores, were more accepting of sentences with attraction errors than YAs. OAs showed longer reading latencies for ungrammatical sentences, again modulated by WM, than YAs. Our results indicate that OAs have greater difficulty blocking intervening nouns from interfering with the computation of agreement dependencies. WM can modulate this effect.     

Minimal functional brain differences between older adults with and without mild cognitive impairment during the stroop

This investigation compared the neural correlates of inhibition in normal older adults (OAs) and OAs with mild cognitive impairment (MCI). It was hypothesized the MCI group would require a greater amount of resources for inhibition, and therefore display greater functional activation in specific regions of interest (ROIs). Twenty-six OAs without and 17 with MCI completed the Stroop task during functional neuroimaging, and completed additional out-of-scanner neuropsychological measures. During inhibition, there were minimal functional Magnetic Resonance Imaging (fMRI) differences found between groups in a priori specified ROIs and with post-hoc multiple regression analyses. However, these minimal differences did not survive corrected thresholds. Robust differences were found with several tasks of a neuropsychological screening battery. The results of this study suggest only very minimal group differences in fMRI activation during inhibition which may not reliably identify MCI, and this condition may be best detected by traditional neuropsychological techniques.     

The effects of ageing and cognitive impairment on on‐line and off‐line motor learning

Skilled performance is a collective function of practice‐related experiences (online learning) and post‐practice memory consolidation during sleep (offline learning). This study examines the effects of ageing and cognitive impairment on the on‐ and offline learning of a point‐to‐point arm movement. In a 3‐day experiment, older adults (cognitively normal or impaired) and young adults (YAs) were randomly assigned to practice or no‐practice conditions. Changes in the dependent measures of movement time and timing error were analysed within and between conditions across days. The findings suggest that both age and cognitive function affect skill learning. YAs improved performance via both on‐ and offline learning whereas older adults with normal cognitive capacities appeared to learn the movement skill primarily in an online mode. Cognitive impairments were found to hinder both types of skill learning. Implications for motor skill acquisition and rehabilitation are briefly discussed. Copyright © 2009 John Wiley & Sons, Ltd.     

Naming Facilitates Young Children's Understanding of Scale Models: Language and the Development of Symbolic Understanding

Two studies examined language and understanding of scale models. First, children (N = 16; ages 2;4 to 3;5) received either the standard DeLoache model task or a naming version (in which children are asked to name the hiding location before retrieving a hidden object). Language ability positively correlated with performance on the model task, and children had significantly more errorless retrievals in the naming condition. Study 2 examined naming and transfer effects by giving children (N = 18; ages 2;5–3;1) both versions of the model task. Language ability correlated significantly only with performance in the naming condition. Both prior experience and naming condition significantly improved performance, with the effects being additive. Language and children's development of symbolic understanding are discussed.     

Age-related cognitive decline as a function of daytime testing

The current study investigates the effects of age, cognitive load, optimal time-of-day testing, and irrelevant background noise suppression on mental processing. One hundred and seventy-eight young (M = 22.97 years) and 114 old adults (M = 56.38 years) were assessed for implicit learning and speed of information processing under irrelevant sound interference early during daytime (7AM–2.30PM) or in the afternoons (3PM–midnight). No direct effect of irrelevant speech effect was found on implicit learning. An optimal time of testing per age group was identified according to the ability to suppress irrelevant auditory information. If no semantic meaning was derived from the sound conditions, irrelevant sound was easily inhibited leaving no room for declined cognitive performance. This suggests an intact phonological inhibition in older adults and a further circumvention of the phonological loop. However, when difficulty was increased, a widened performance gap between young and old people could be observed. Education modulated difficult performance irrespective of age. With increasing age, task demand fulfillment becomes a function of a limited time mechanism. If extraneous time is not adapted to cognitive skills and performance, higher order processing cannot be reached, rendering older adults slower than their younger counterparts.     

Mental rotation performance and the effect of gender in fourth graders and adults

The DSM-IV implicitly assumes that development is uniform across ability domains, which implies that relationships between ability measures do not differ across development. We assessed whether correlations between measures of nine ability constructs differed across samples of children aged 3 – 5 (n = 117), 6 – 8 (n = 116), 9 – 11 (n = 124) and 12 – 14 years (n = 92). LISREL analyses show that correlations in each age group differ from those of each other age group. Parallel analyses indicate that the latent structure of ability differs across age groups. We conclude that shared maturational processes, including changes in the connectivity of neural systems, are responsible for decreasingly and increasingly strong relationships between some ability measures.     

Force Control of Ankle Dorsiflexors in Young Adults: Effects of Bilateral Control and Leg Dominance

Abstract

We investigated whether bilateral lower-limb control and leg dominance affect force control ability in 15 healthy young adults (9 males and 6 females, age =26.8?±?4.1 years). Participants performed isometric ankle dorsiflexion force control tasks, matching a visual target (10% of maximal effort) as quickly and precisely as possible in ballistic and tonic tasks. Performance was evaluated using force error, force steadiness, amount of muscle activity of the tibialis anterior, and response time characteristics. Results showed no significant effects of leg dominance during both ballistic and tonic tasks, while bilateral condition resulted in significantly larger error, less force steadiness, compared to unilateral condition, and only during the tonic task. Consequently, bilateral control, specifically in tasks utilizing feedback control (i.e., tonic task) might affect force control ability, possibly because of the interhemispheric inhibition to meet bilateral task complexity and integrate afferent bilateral sensory information from both right and left legs.     

Prospective Associations Between Prosocial Behavior and Social Dominance in Early Childhood: Are Sharers the Best Leaders?

A short-term longitudinal study during early childhood (N = 96; M = 42.80; SD = 7.57) investigated the concurrent and prospective association between prosocial behavior and social dominance. Time-intensive school-based focal child sampling with continuous recording observations of prosocial behavior to peers were conducted and teacher-reports of social dominance were collected. The study documents significant prospective links between prosocial behavior to peers and increases in social dominance over time. Social dominance was not associated with changes in prosocial behavior. The findings extend past empirical work in early childhood and future directions are discussed.     

Working memory in very-low-birthweight children at the age of 11 years

The aim of this study is to investigate the working memory (WM) of very-low-birthweight (VLBW, ≤ 1500 g) children at the age of 11 years using Baddeley’s WM model. A regional cohort of 95 VLBW children was assessed for the domains of the WM model (central executive [CE], visuospatial sketchpad [VS], and phonological loop [PL]) using subtests from the Working Memory Test Battery for Children (WMTB-C) and the Wechsler Intelligence Scale for Children – Fourth Edition (WISC-IV). VLBW children were categorized into three groups according to their degree of brain pathology (normal, minor, or major) in neonatal brain magnetic resonance imaging at the term age, and the WM performance was compared between groups to test norms. The structure of the WM model was studied by analyzing correlations among domains. Even VLBW children with normal cognitive development (general ability index ≥ 85) performed worse compared to the test norms (M = 100, SD = 15) on CE (M = 87.64, SD = 20.54, p < .001) and VS (M = 91.65, SD = 11.03, p < .001), but their performance on PL was above the norm (M = 110.79, SD = 13.79, p < .001). VLBW children with major brain pathology performed significantly worse on VS and PL compared to the other groups. The correlations among the WM domains of the VLBW children differ from earlier findings in normative populations. To conclude, the WM of the VLBW children in the study differ—especially in the CE and VS subtest scores—from the normative population irrespective of the degree of brain pathology and level of cognitive development.     

Relationship of cognitive strategy use to prospective memory performance in a diverse sample of nondemented older adults with varying degrees of cognitive complaints and impairment

Although older adults typically have better performance on prospective memory (PM) tasks carried out in naturalistic settings, a paucity of research directly assesses older adults’ use of compensatory strategies on such tasks. The current study investigates external memory strategy use during performance of a clinical PM test that features both short-term (in laboratory) and long-term (out of laboratory) subtasks (i.e., the Royal Prince Alfred Prospective Memory Test – RPA-ProMem. Nondemented, community-dwelling older adults (n = 214; mean age = 80.5; 68.2% female; 39.7% non-white) with mild cognitive impairment, subjective cognitive decline, and healthy controls completed the RPA-ProMem while external strategy use was permitted and recorded. Overall, participants utilized external strategies 41% of the time on the RPA-ProMem. Increased utilization of external memory strategies was significantly associated with better PM performance. Additionally, better performance on executive functioning tasks was associated with increased use of external memory strategies. Results are discussed in relation to how memory strategy use can be enhanced to improve everyday memory ability in older adults at risk for dementia.     

Texture development during cross rolling of a dual-phase Fe–Cr–Ni alloy: experiments and simulations

Texture development during multi-step cross rolling of a dual-phase Fe–Cr–Ni alloy has been investigated. X-ray diffraction was used to investigate changes in crystallographic texture of both the constituent phases (austenite and ferrite) through changes in orientation distribution function. After deformation, rotated brass (rotated along φ₁, i.e. the sample normal direction ND), along with a weak cube texture was observed in austenite, while a strong rotated cube texture was obtained in ferrite. Texture was also simulated for various strains using a co-deformation model by self-consistent visco-plastic (VPSC) formulation. Simulations showed strong rotated brass texture in austenite and a strongly rotated cube, α-fibre (sample rolling direction RD //<1 1 0>) and γ-fibre (ND //<1 1 1>) in ferrite after highest strain (ε_t = 1.6). VPSC models could not effectively capture the change in crystallographic texture during cross rolling. In ferrite, simulations showed an overestimation of γ-fibre component and an underestimation of rotated cube component. Simulated texture of austenite, on the other hand, showed an overestimation of rotated brass with an absence of cube component. The results are rationalised based on the possible role of shear banding and activation of non-octahedral slip system during cross rolling, both of which are not incorporated in conventional VPSC models.     

Social cognition is not associated with cognitive reserve in older adults

Social and general cognitive abilities decline in late life. Those with high cognitive reserve display better general cognitive performance in old age; however, it is unknown whether this is also the case for social cognition. A total of 115 healthy older adults, aged 60–85 years (m = 44, f = 71) were assessed using The Awareness of Social Inference Test (TASIT-R; social cognition), the Lifetime of Experiences Questionnaire (LEQ; cognitive reserve), and the Wechsler Abbreviated Scale of Intelligence (WASI-II; general cognitive ability). The LEQ did not predict performance on any TASIT-R subtest: Emotion Evaluation Test (β = -.097, p = .325), Social Inference – Minimal (β = -.004, p = .972), or Social Inference – Enriched (β = -.016, p = .878). Sensitivity analyses using two alternative cognitive reserve measures, years of education and the National Adult Reading Test, supported these effects. Cognitive reserve was strongly related to WASI-II performance. Unlike general cognitive ability, social cognition appears unaffected by cognitive reserve. Findings contribute to the emerging understanding that cognitive reserve differentially affects individual cognitive domains, which has implications for the theoretical understanding of cognitive reserve and its brain correlates. Cognitive measures unbiased by cognitive reserve may serve as best indicators of brain health, free of compensatory mechanisms.     

Faces in Motion: Age‐Related Changes in Eyewitness Identification Performance in Simultaneous,Sequential, and Elimination Video Lineups

The identification performance of children (5 to 6 years, n = 180; 9 to 10 years, n = 180) and adults (n = 180) was examined using three types of video lineup procedures: simultaneous, sequential and elimination. Participants viewed a videotaped staged theft and then attempted to identify the culprit from a target‐present or target‐absent video lineup. Correct identifications in simultaneous and elimination video lineups did not differ as a function of age. The sequential video lineup was associated with a reduction in correct identifications for both child groups compared with adults. With respect to the target‐absent lineup condition, the video elimination lineup was associated with an increase in correct rejection rates for adult witnesses. Age was also significantly associated with accuracy. Differences in correct rejection rates were observed between adults and children and also between the two child groups. Implications and future directions are discussed. Copyright © 2011 John Wiley & Sons, Ltd.     

Cross-sectional and longitudinal analyses of everyday memory lapses in older adults

Everyday memory lapses experienced by older adults (OAs) were examined using a daily-diary checklist and retrospective questionnaire. In Experiment 1, 138 younger and 138 OAs indicated the frequency of forgetting of 16 memory lapses, and whether each occurred daily during the course of a week. OAs reported more memory lapses on the questionnaire, but not the daily diary. OAs reported more frequently forgetting names and words, while younger adults had more difficulty with appointments and personal dates. Fewer memory lapses on the daily diary were related to better performance on a laboratory-memory measure for OAs. In Experiment 2, 62 OAs returned for a five-year follow-up and endorsed experiencing more memory lapses on the daily diary compared to baseline, specifically forgetting more names and words, but not the retrospective questionnaire. Daily checklist memory lapses again correlated with the laboratory-memory measure. A daily checklist may be a viable way to assess everyday memory lapses.     

Visual scanning patterns and executive function in relation to facial emotion recognition in aging

ABSTRACT

Objective: The ability to perceive facial emotion varies with age. Relative to younger adults (YA), older adults (OA) are less accurate at identifying fear, anger, and sadness, and more accurate at identifying disgust. Because different emotions are conveyed by different parts of the face, changes in visual scanning patterns may account for age-related variability. We investigated the relation between scanning patterns and recognition of facial emotions. Additionally, as frontal-lobe changes with age may affect scanning patterns and emotion recognition, we examined correlations between scanning parameters and performance on executive function tests. Methods: We recorded eye movements from 16 OA (mean age 68.9) and 16 YA (mean age 19.2) while they categorized facial expressions and non-face control images (landscapes), and administered standard tests of executive function. Results: OA were less accurate than YA at identifying fear (p < .05, r = .44) and more accurate at identifying disgust (p < .05, r = .39). OA fixated less than YA on the top half of the face for disgust, fearful, happy, neutral, and sad faces (p values < .05, r values ≥ .38), whereas there was no group difference for landscapes. For OA, executive function was correlated with recognition of sad expressions and with scanning patterns for fearful, sad, and surprised expressions. Conclusion: We report significant age-related differences in visual scanning that are specific to faces. The observed relation between scanning patterns and executive function supports the hypothesis that frontal-lobe changes with age may underlie some changes in emotion recognition.     

Age and pre quit-day attrition during smoking cessation treatment

ABSTRACT

The present study aimed to replicate the finding that younger age predicts higher pre quit-day attrition. Our second aim was to explain this relation by examining empirically and theoretically informed age-related risk factors for low smoking cessation treatment engagement. 136 participants (M _age = 44.2 years, SD = 11.3 years; age = 22–64 years) were randomized to 15-weeks of either 1) an exercise intervention (n = 72) or 2) a wellness education control condition (n = 64). First, a logistic regression analysis was employed to test whether younger adults were more likely than older adults to drop prior to quit date. Next, we assessed whether smoking related health concerns, social expectancies, and/or perceived severity of craving affected the strength of the relation between age and attrition, by adding these three variables to the logistic regression along with age. The logistic regression model indicated that younger age and treatment condition were significantly related to the odds of dropping from treatment prior to the scheduled quit date. Further, health concerns, social expectancies, and/or perceived severity of cravings did not account for the effect of age on pre quit-day attrition. These findings highlight the importance of identifying empirically and theoretically informed variables associated with the pre quit-day attrition problem of young smokers.     

Changing dominance in mixed profession groups: putting theory into practice

An extended professional identity theory is proposed to enhance interprofessional collaboration. The purpose of this study is to investigate whether comparative feedback on interprofessional interaction can decrease the degree of profession-based dominance and general dominance in mixed profession groups. This observational study comprised a randomized double-blind pretest-posttest control group design with 19 mixed profession groups (10 intervention and nine control groups, each with three dental and three dental hygiene students). All groups received reflective feedback during two consecutive two hour team development meetings. Intervention groups also received comparative feedback. Profession-based dominance concerned the sum of three observation items (conversational turn-taking, dominance and contributing ideas) with a three-point scale: ?1 = dental dominance, 0 = no dominance, +1 = dental hygiene dominance. Polychoric correlations confirmed positive associations with the latent trait and an unidimensional underlying structure. Observation items were internally consistent (α > .70). General dominance concerned the sum of absolute values of observation items with a minimum value of zero (no dominance) and the maximum value of three (strong dominance). A two-way factorial ANOVA was performed. The results revealed a significant interaction effect with regard to general dominance, F(1,17) = 6.630, p = 0.020 and large effect size (partial eta squared = 0.28). Comparative feedback on interprofessional interaction decreases general dominance in mixed profession groups.