Further evidence for temporal decay in working memory: reply to Lewandowsky and Oberauer (2009)

The sources of forgetting in working memory (WM) are a matter of intense debate: Is there a time-related decay of memory traces, or is forgetting uniquely due to representation-based interference? In a previous study, we claimed to have provided evidence supporting the temporal decay hypothesis (S. Portrat, P. Barrouillet, & V. Camos, 2008). However, reanalyzing our data, S. Lewandowsky and K. Oberauer (2009) demonstrated that they do not provide compelling evidence for temporal decay and suggested a class of alternative models favoring a representation-based interference account. In this article, we develop from the most recent proposals made by Lewandowsky and Oberauer 2 of the most plausible extensions of these alternative models. We show that neither of these extensions can account for recent findings related to between-domain WM performance and that both lead to predictions that are contradicted by new empirical evidence. Finally, we show that recent studies that have been claimed to rule out the temporal decay hypothesis do not resist close scrutiny. We conclude that the time-based resource-sharing model remains the most parsimonious way to account for forgetting and restoration of memory traces in WM.     

Attention and cognitive control networks assessed in a dichotic listening fMRI study

A meaningful interaction with our environment relies on the ability to focus on relevant sensory input and to ignore irrelevant information, i.e. top-down control and attention processes are employed to select from competing stimuli following internal goals. In this, the demands for the recruitment of top-down control processes depend on the relative perceptual salience of the competing stimuli. In the present functional magnetic resonance imaging (fMRI) study, we investigated the recruitment of top-down control processes in response to varying degrees of control demands in the auditory modality. For this purpose, we tested 20 male and 20 female subjects with a dichotic listening paradigm, in which the relative perceptual salience of two simultaneously presented stimuli was systematically manipulated by varying the inter-aural intensity difference (IID) and asking the subjects to selectively attend to either ear. The analysis showed that the interaction between IID and attentional direction involves two networks in the brain. A fronto-parietal network, including the pre-supplementary motor area, anterior cingulate cortex, inferior frontal junction, insula and inferior parietal lobe, was recruited during cognitively demanding conditions and can thus be seen as a top-down cognitive control network. In contrast, a second network including the superior temporal and the post-central gyri was engaged under conditions with low cognitive control demands. These findings demonstrate how cognitive control is achieved through the interplay of distinct brain networks, with their differential engagement determined as a function of the level of competition between the sensory stimuli.     

Motor skill learning in the middle-aged: limited development of motor chunks and explicit sequence knowledge

The present study examined whether middle-aged participants, like young adults, learn movement patterns by preparing and executing integrated sequence representations (i.e., motor chunks) that eliminate the need for external guidance of individual movements. Twenty-four middle-aged participants (aged 55–62) practiced two fixed key press sequences, one including three and one including six key presses in the discrete sequence production task. Their performance was compared with that of 24 young adults (aged 18–28). In the middle-aged participants motor chunks as well as explicit sequence knowledge appeared to be less developed than in the young adults. This held especially with respect to the unstructured 6-key sequences in which most middle-aged did not develop independence of the key-specific stimuli and learning seems to have been based on associative learning. These results are in line with the notion that sequence learning involves several mechanisms and that aging affects the relative contribution of these mechanisms.     

Smoking reduces language lateralization: a dichotic listening study with control participants and schizophrenia patients

Schizophrenia has been associated with deficits in functional brain lateralization. According to some authors, the reduction of asymmetry could even promote this psychosis. At the same time, schizophrenia is accompanied by a high prevalence of nicotine dependency compared to any other population. This association is very interesting, because sex-dependent effects of smoking in auditory language asymmetries have been reported recently, and the verbal domain is also one major focus in cognitive deficit studies of schizophrenia. Thus, the altered laterality pattern in schizophrenia could, at least in part, result from secondary artefacts due to smoking rather than being a pure cause of the disease itself. To test this hypothesis, the present study examined auditory language lateralization in 67 schizophrenia patients and in 72 healthy controls in a phonemic and an emotional dichotic listening task. Our findings replicate previous research, in that smoking reduces language lateralization in men in phonemic dichotic listening. In addition, we show that smoking also reduces laterality in women in the emotional dichotic listening task. Thus, smoking alters phonemic and emotional language asymmetries differentially for men and women, with a stronger effect for men in the left hemisphere phonemic task, and a stronger effect for women in the right hemisphere emotional task. Together, these findings point towards an effect of smoking which is possibly independent of sex and hemisphere. Importantly, by testing equal numbers of smoking and non-smoking patients and controls, we found no schizophrenia-associated asymmetry effect. Possible neurobiological mechanisms with which smoking may alter auditory microcircuits and thereby diminish left-right differences are discussed.     

Borderline personality traits in nonclinical young adults

The main purpose of this study was to explore the dimensionality of the borderline personality disorder in nonclinical young adults by means of the Borderline Personality Questionnaire (BPQ; Poreh et al., 2006). We also studied the phenotypic expression of the borderline personality traits as a function of participants' gender and age, and the relationship between BPQ subscales and measures of depressive symptoms, anxiety, stress, hallucinatory predisposition, and paranoid ideation. The sample comprised 809 young adults, 562 (69.5%) were women, with a mean age of 20.2 years (SD = 2.9). The results indicate that the BPQ self-report has adequate psychometric properties. The levels of internal consistency for the BPQ subscales ranged between .78 and .93. Analysis of the internal structure of the BPQ subscales yielded a one-dimensional solution. In contrast, second-order principal components analysis at the item level yielded a five-dimensional solution. Likewise, statistically significant differences in the mean scores of the borderline personality traits as a function of participants' gender and age were found. The BPQ subscales correlated significantly with measures of depression, anxiety, stress, paranoid ideation, and hallucinatory predisposition. These results help to improve our understanding of the dimensional structure of the borderline personality in the general population. Future research should continue to identify participants who are at risk for the development of borderline personality disorder and facilitating the development of early detection and prevention programs.     

Growth in infancy and childhood and hospitalization for personality disorders in adulthood: the Helsinki Birth Cohort Study

This study examined the associations between infant and childhood growth and severe personality disorders. Among 4,689 men and 4,200 women of the Helsinki Birth Cohort Study 1934-1944, 81 men and 68 women had been hospitalized with an ICD (-8, -9, -10) diagnosis of personality disorder in adulthood. Among men, slower gain in BMI between birth and 6 months, faster gain in weight and BMI between 6 months and 1 year, and slower gains in them between 7 and 11 years of age predicted an increased risk of hospitalization for personality disorders. Thinness at 6 months and again at 11 years also showed significant association with personality disorders among men. Among women, slower gain in height between 2 and 7 years predicted hospitalization for personality disorders. Our findings show the importance of early growth as a vulnerability factor of personality disorders severe enough to justify hospitalization.     

Amniocentesis Due to Advanced Maternal Age: The Role of Marital Intimacy in Couples’ Decision-Making Process

Due to the risk of fetal anomaly, pregnant women of advanced maternal age are given the option to undergo amniocentesis. In our study we aimed to describe couples’ decision-making process regarding amniocentesis, and assess whether it is influenced by marital intimacy and men’s participation in genetic counseling. During pregnancy, 112 couples answered the Personal Assessment of Intimacy in Relationships questionnaire and scales regarding the decision to undergo amniocentesis. Most couples shared and reached an agreement regarding this decision. Higher levels of marital engagement and communication, but not men’s participation, were associated with higher agreement, influence, and decision-sharing. Clinical implications are discussed.     

Do positive illusions predict overconfidence in judgment? A test using interval production and probability evaluation measures of miscalibration

We address the question as to whether judgmental overconfidence, as assessed by probability miscalibration, is related to positive illusions about the self. We first demonstrate that judgmental overconfidence measured with interval production procedures can be considered a trait, due to correlations observed in miscalibration scores in two sets of general‐knowledge questions of varying difficulty administered at different times. In addition, the hard‐easy effect operated in different ways on overprecision and self‐placement of one's performance relative to others: The more difficult the calibration task, the greater the over precision but the greater the under placement of one's performance. Finally, there was no evidence that miscalibration was related to dispositional optimism and self‐efficacy. A second study extended these results by including further measures of disposition to experience positive illusions such as unrealistic optimism, a general tendency to consider oneself “better‐than‐average,” and two indexes of dispositional perception of control. The positive illusion measures showed considerable inter‐correlations, but did not correlate with miscalibration on the interval production task, and correlated negatively with optimism concerning societal risks. A final study replicated this pattern of findings, but showed that disposition to positive illusions did predict miscalibration on the same questions measured with a probability evaluation technique. Our research demonstrates that “overconfidence” is not a unitary construct, but a series of overlapping ones. Copyright © 2010 John Wiley & Sons, Ltd.     

Children's activities and their meanings for parents: a mixed-methods study in six Western cultures

Theoretical perspectives and research in sociology, anthropology, sociolinguistics, and cultural psychology converge in recognizing the significance of children's time spent in various activities, especially in the family context. Knowing how children's time is deployed, however, only gives us a partial answer to how children acquire competence; the other part must take into account the culturally constructed meanings of activities, from the perspective of those who organize and direct children's daily lives. In this article, we report on a study of children's routine daily activities and on the meanings that parents attribute to them in six Western middle-class cultural communities located in Italy, The Netherlands, Poland, Spain, Sweden, and the United States (N = 183). Using week-long time diaries kept by parents, we first demonstrate similarities as well as significant differences in children's daily routines across the cultural samples. We then present brief vignettes--"a day in the life" --of children from each sample. Parent interviews were coded for themes in the meanings attributed to various activities. Excerpts from parent interviews, focusing on four major activities (meals, family time, play, school- or developmentally related activities), are presented to illustrate how cultural meanings and themes are woven into parents' organization and understanding of their children's daily lives. The results of this mixed-method approach provide a more reliable and nuanced picture of children's and families' daily lives than could be derived from either method alone.     

Interpersonal aggression and team effectiveness: The mediating role of team goal commitment

This study examines the detrimental effect that interpersonal aggressive behaviours may have on two dimensions of team effectiveness, namely team performance and team viability. Moreover, this study investigates the mediating role of team goal commitment in these relationships. Data were collected from 97 work teams (341 members and 97 immediate supervisors) working in a public safety organization. The results indicate that interpersonal aggression is negatively related to team performance and team viability. The results also show that team goal commitment exercises a complete mediating role with regard to these relationships. Overall, this study highlights potential negative consequences of interpersonal aggression at the team level.