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.     

The influence of handedness on profile and line drawing directionality in children,young, and older normal adults

One hundred twenty-two normal subjects--children, young and older adults (77 right-handers and 45 left-handers)--performed two drawing tasks in order to study their directionality trends. The first task consisted of drawing the profile of a face and in the second task subjects had to link two points in order to draw a line. The analysis of the drawing directionality revealed a significant effect of the age when right-handers drew profiles whereas this effect reached significance in left-handed subjects only when drawing lines. Left- and right-handers' performances across the two tasks were found to significantly differ. Results are discussed in terms of hemispheric and environmental factors.     

Cognitive abilities explaining age-related changes in time perception of short and long durations

The current study investigated how the development of cognitive abilities explains the age-related changes in temporal judgment over short and long duration ranges from 0.5 to 30 s. Children (5- and 9-year-olds) as well as adults were given a temporal bisection task with four different duration ranges: a duration range shorter than 1 s, two duration ranges longer than 3 s (4-8 s and >15 s), and an intermediate duration range (1.25-2.5 s). Their cognitive abilities were also assessed using a series of neuropsychological tests. The results showed that temporal sensitivity improved with age for each duration range but that this improvement occurred earlier for the short durations than for the long durations. Furthermore, the results revealed that the age-related improvement in time sensitivity for the durations shorter than 1 s was explained by the development of short-term memory span, whereas that for long durations was explained by the development of attention/executive functions. To summarize, the development of the abilities required to process long durations seems to be explained mainly by the development of attentional resources.     

Genetic testing for hereditary cancer: effects of alexithymia and coping strategies on variations in anxiety before and after result disclosure

This study assessed the impact of the results of genetic testing for hereditary cancer from a multifactorial health psychology perspective, considering that emotional expression plays a key role in psychological adjustment. Measures of dispositional and transactional coping strategies, anxiety and alexithymia were filled out by 77 participants in a longitudinal study design. Statistical analyses were performed using general linear models and partial least squares path modelling, low-constraint methods that are particularly useful in the behavioural sciences. While anxiety levels prior to the result announcement were predictive of the distress experienced by noncarriers, considerable variability was observed for mutation carriers. Some subjects who had lower anxiety levels before the test displayed greater anxiety afterwards, but others seemed to anticipate the distress they would experience with the result that they showed a decrease in anxiety. The mutation carriers behaved as though their adaptive functioning were reshaped by the test result, independent of their disposition and previous emotional state, except in the case of alexithymia. Difficulty expressing emotions prior to genetic testing contributed to a similar difficulty after receiving the result, adding to the latter's emotional impact by promoting emotion-focused coping strategies and increasing distress.     

Temperament Alters Susceptibility to Negative Peer Influence in Early Adolescence

The role of deviant peers in adolescent antisocial behavior has been well documented, but less is known about individual differences in susceptibility to negative peer influence. This study examined whether specific temperament dimensions moderate the prospective relationship between peer deviance and delinquent behavior in early adolescence. Participants included 704 adolescents recruited from the community. At baseline, parents provided information on adolescents’ temperament and youth reported on their own and their friends’ delinquent behavior. Self-reports of adolescents’ delinquent behavior were collected again 16 months later. Peer deviance was related to delinquent behavior over time more strongly for adolescents with low levels of task orientation, flexibility, and positive mood, compared to youth with high levels of task orientation, flexibility, and positive mood. Analyses of gender differences indicated that low flexibility increased susceptibility to negative peer influence only for males, but not females. General activity level and sleep rhythmicity did not moderate the effect of peer behavior on delinquency.     

Emotional time distortions: the fundamental role of arousal

An emotion-based lengthening effect on the perception of durations of emotional pictures has been assumed to result from an arousal-based mechanism, involving the activation of an internal clock system. The aim of this study was to systematically examine the arousal effect on time perception when different discrete emotions were considered. The participants were asked to verbally estimate the duration of emotional pictures from the International Affective Picture System (IAPS). The pictures varied either in arousal level, i.e., high/low-arousal, for the same discrete emotion (disgust or sadness) or in the depicted emotion, e.g., disgust/fear for pictures matched for arousal (high-arousal). The results systematically revealed a lengthening effect on the perception of the duration of the emotional compared to the neutral pictures and indicated that the magnitude of this effect increased with arousal level. Nevertheless, variations in time perception were observed for one and the same arousal level, with the duration of disgust-inducing pictures (e.g., body mutilation) being judged longer than that of fear-inducing pictures (e.g., snake). These results suggest that arousal is a fundamental mechanism mediating the effect of emotion on time perception. However, the effect cannot be reduced to arousal, since the impact of the content of pictures also plays a critical role.     

Future Time Perspective according to women's age and social role during adulthood

The purpose of the present research was to describe the kind of transformation Future Time Perspective (FTP) undergoes during adulthood and to investigate the differences that may occur in the extension and the content of goals of women according to their age groups and social roles (homemakers, students, and careerwomen). With a sentence completion technique, 622 Caucasian French-Canadian women (20 to 64 years of age) expressed their aspirations. These goals were classified into specific categories according to their temporal extension and their motivational content. Results indicate that the extension and the content of FTP undergo numerous changes during adulthood, revealing different goal profiles according to women's age and social role. Results are discussed in relation with current research.The authors are most grateful to the psychology students of the University of Sherbrooke for their contribution during the data gathering.     

Proper Name Hypermnesia in an Autistic Subject

The case study of an autistic “savant” subject with person names hypermnesia is presented. NM's performance in memorizing person names is compared to that of normal controls, IQ-matched controls, and one overtrained control. The data show a selective hypermnesia for both the free recall of person names and the recognition of faces. Recall of common names and of biographical informations linked to faces is unremarkable. NM's hypermnesia is restricted to list learning as low performance is observed in face-name learning tasks. A comparison of the data with that of the overtrained control indicates that training is not responsible for NM's pattern of results. These findings, when combined with previous results involving proper names, demonstrate a double dissociation between proper names and other types of semantic and referential information. However, aspects of NM's performance pattern are more compatible with a network model of proper names than with a sequential model. We propose that the contextual regularity of proper names in ecological situations can be responsible for their high memorization by NM.     

Are Time and Action Dissociated in Young Children''s Time Estimation?

Experiment 1 examined whether there is a developmental shift in children's ability to differentiate a given amount of time from a particular action. In three sessions, 3- and 5 1/2-year-olds were trained to produce an action (i.e., pressing on a squeezer) for 5 s. Twenty-four hours later, control participants were required to produce this target duration using the same action, whereas experimental participants had to do so with a new action (i.e., pressing a button). The results showed that the 5 1/2-year-olds achieved the same temporal performance in both groups. In contrast, the 3-year-olds' temporal performance was significantly better in the control group than in the experimental group. Two additional studies were run with 3-year-olds, the first designed to assess the transfer without a delay, and the second with explicit instructions to transfer duration. In each study, 3-year-olds' temporal performance was significantly better in the control group than in the experimental group. These findings as a whole suggest that 3-year-olds fail to understand that one and the same duration can be shared by several different actions. Early implicit knowledge of time was discussed.