Reduced short-term memory capacity in Alzheimer's disease: the role of phonological, lexical, and semantic processing

Individuals with Alzheimer's disease (AD) are often reported to have reduced verbal short-term memory capacity, typically attributed to their attention/executive deficits. However, these individuals also tend to show progressive impairment of semantic, lexical, and phonological processing which may underlie their low short-term memory capacity. The goals of this study were to assess the contribution of each level of representation (phonological, lexical, and semantic) to immediate serial recall performance in 18 individuals with AD, and to examine how these linguistic effects on short-term memory were modulated by their reduced capacity to manipulate information in short-term memory associated with executive dysfunction. Results showed that individuals with AD had difficulty recalling items that relied on phonological representations, which led to increased lexicality effects relative to the control group. This finding suggests that patients have a greater reliance on lexical/semantic information than controls, possibly to make up for deficits in retention and processing of phonological material. This lexical/semantic effect was not found to be significantly correlated with patients' capacity to manipulate verbal material in short-term memory, indicating that language processing and executive deficits may independently contribute to reducing verbal short-term memory capacity in AD.     

Risk factors for addictive disorders: a discriminant analysis on 374 addicted and 513 nonpsychiatric participants

Many common risk factors have been described in addictive disorders. Little is known about factors' respective contributions to discrimination of addicted and nonaddicted participants. Two large samples were compared including 513 nonpsychiatric participants and 374 addicted participants meeting the DSM-IV criteria for eating disorders, alcohol, or substance dependence. Twenty-six risk factors were assessed by interview or self-rating scales. A discriminant analysis determined the respective weight of each risk factor. One discriminant function emerged and characterized a depressive dimension. The results suggest that the different risk factors described in addiction could be related to a depressive dimension.     

A further analysis of time bisection behavior in children with and without reference memory: the similarity and the partition task

Experiment 1 compared the temporal performance of 5-year-olds, 8-year-olds and adults in a bisection task with and without referent durations (similarity vs. partition). The results showed that temporal sensitivity was lower in the partition than in the similarity condition in children, whereas it was similar in these two conditions in the adults. In addition, the 5-year-olds produced a higher bisection point value in the partition than in the similarity task. Experiment 2, which examined changes in bisection performance over the trial blocks in the partition task, revealed that the 5-year-olds' bisection performance improved over the trial blocks, whereas the performance of the older participants did not. Further analyses revealed a greater variability in the establishment of the duration criterion in young children.     

Bidirectional Influences of Violence Exposure and Adjustment in Early Adolescence: Externalizing Behaviors and School Connectedness

This study utilized cross-lagged longitudinal models to examine prospective, bidirectional relationships between witnessing violence and victimization and three adjustment variables—delinquency, conduct problems, and school connectedness. Participants included 603 early adolescent boys and girls (78% African American, 20% Caucasian). Witnessing violence was related to subsequent lower levels of school connectedness and more conduct problems. For Caucasian but not African American adolescents, witnessing violence also predicted later delinquency. Victimization was linked with lower school connectedness over time, and for boys but not girls also with more conduct problems. Only adolescent delinquency was associated with subsequent witnessing violence and victimization. This research was partially supported by the Centers for Disease Control and Prevention Grant No. R49–CCR418569.     

Musical and verbal memory in Alzheimer’s disease: A study of long-term and short-term memory

Musical memory was tested in Alzheimer patients and in healthy older adults using long-term and short-term memory tasks. Long-term memory (LTM) was tested with a recognition procedure using unfamiliar melodies. Short-term memory (STM) was evaluated with same/different judgment tasks on short series of notes. Musical memory was compared to verbal memory using a task that used pseudowords (LTM) or syllables (STM). Results indicated impaired musical memory in AD patients relative to healthy controls. The deficit was found for both long-term and short-term memory. Furthermore, it was of the same magnitude for both musical and verbal domains whether tested with short-term or long-term memory tasks. No correlation was found between musical and verbal LTM. However, there was a significant correlation between verbal and musical STM in AD participants and healthy older adults, which suggests that the two domains may share common mechanisms.     

The assessment of recognition memory using the Remember/Know procedure in amnestic mild cognitive impairment and probable Alzheimer’s disease

This study used the Remember/Know (R/K) procedure combined with signal detection analyses to assess recognition memory in 20 elders with amnestic mild cognitive impairment (aMCI), 10 patients with probable Alzheimer’s disease (AD) as well as matched healthy older adults. Signal detection analyses first indicated that aMCI and control participants were comparable on general recognition performance. As regards AD patients, they were impaired relative to both aMCI and healthy elders. When assessing Remember and Know responses the aMCI group showed diminished sensitivity for Remember responses but intact Know responses compared to healthy elders. In contrast, AD patients showed decreased sensitivity for both Remember and Know responses compared to control and aMCI participants. The response bias index revealed that AD patients were more liberal than aMCI and control participants when providing Know responses. On the other measures, response bias was comparable between the groups. Overall, this study indicates that the R/K procedure can characterize different aspects of recognition memory performance in persons with aMCI or AD.     

Scientific, political, ethical, or pragmatic issues in the collection of ethnic statistics: an exploratory survey in public institutions in Montréal

In recent years, ethnic statistics have been at the core of a passionate debate in many Europeans countries. This debate has been as much about the political legitimacy of ethnoracial data collection in the census as it has been about the scientific legitimacy of ethnic statistics to understand social inequality and discrimination. These questions have not provoked the same kind of intense debate among academics in Canada. However, very few studies have examined the relevance of these issues beyond the census. This paper presents results of an exploratory study conducted with 14 major public institutions across diverse sectors including health, law enforcement and public safety, social services, and housing in Montréal. Investigating which institutions collects ethnic statistics and why, the study examined the political, scientific, ethical, and pragmatic issues raised by local managers.     

Testing the representation of time in reference memory in the bisection and the generalization task: the utility of a developmental approach

This study examined the effect of the variability of representation of durations in reference memory on temporal discrimination performance in children aged 5 and 8 years as well as in adults using a bisection (Experiment 1) and a generalization task (Experiment 2). In each task, the participants were familiarized before the blocks of tested trials with either the same referent duration values (fixed condition) or a distribution of referent duration values, with a mean equal to the referent durations used in the fixed condition and a .20 coefficient of variation (variable condition). The results showed that the sensitivity to duration was lower in the variable than in the fixed condition in the children and, to a lesser extent, in the adults. The modelling of the data indicated that this effect was due to the increase in the variability of the representation of durations in reference memory, but also to changes in the decisional processes.     

Scalar timing in temporal generalization in children with short and long stimulus durations.

This experiment investigated temporal generalization performance in children aged 3, 5, and 8 years by using auditory stimulus durations where the standard was 0.4 s or 4.0 s, and non-standard stimuli were spaced linearly around the standard. At all ages, generalization gradients superimposed well when plotted on the same relative scale, indicating conformity to scalar timing. Whatever the standard duration used, the principal developmental changes were the increasing steepness of the generalization gradient with increasing age and a shift from symmetrical gradients, in the 3- and 5-year-olds, to adult-like asymmetrical gradients in the 8-year-olds.     

Parental and family predictors of behavior problems in inner-city black children

Studied contributions of maternal psychological distress, family stress load, maternal and family risk factors, and family coping strategies in predicting behavior problems in 441 inner-city black primary-grade children. Results indicated maternal psychological distress and high family stress load were associated with high child behavior problems. Family coping strategies offered no protection against risk, while coping with life difficulties by reframing them was detrimental to child behavioral adjustment. Active help-seeking strategies (i.e., family mobilization, acquiring social supports) served to moderate the effects of maternal psychological distress and family risk attributes for boys, but exacerbated the effects of dysfunctional maternal social and psychiatric histories for girls. Implications for understanding vulnerability and resilience in inner-city black children and recommendations for future research are discussed.