Processing speed in normal aging: Effects of white matter hyperintensities and hippocampal volume loss

Changes in cognitive functioning are said to be part of normal aging. Quantitative MRI has made it possible to measure structural brain changes during aging which may underlie these decrements which include slowed information processing and memory loss. Much has been written on white matter hyperintensities (WMH), which are associated with cognitive deficits on tasks requiring processing speed and executive functioning, and hippocampal volume loss, which is associated with memory decline. Here we examine volumetric MRI measures of WMH and hippocampal volume loss together in relation to neuropsychological tests considered to be measures of executive functioning and processing speed in 81 non-demented elderly individuals, aged 75–90. Correlational analysis showed that when controlling for age, both greater WMH volume and smaller hippocampal volume were correlated with slower performances on most tests with the exception of a battery of continuous performance tests in which only WMH was correlated with slower reaction time (RT). We then performed a series of hierarchical multiple regression analyses to examine the independent contributions of greater WMH volume and reduced hippocampal volume to executive functioning and processing speed. The results showed that for the four measures requiring executive functioning and speed of processing, WMH volume and hippocampal volume combined predicted between 21.4% and 37% of the explained variance. These results suggest that WM integrity and hippocampal volume influence cognitive decline independently on tasks involving processing speed and executive function independent of age.     

Asymmetry of automatic change detection shown by the visual mismatch negativity: An additional feature is identified faster than missing features

In two experiments, we demonstrated that an asymmetric effect of the brain electric activity that is elicited by nonattended visual stimuli is similar to the one found in responses observed in the performance of visual search tasks. The automatic detection of violated sequential regularities was investigated by measuring the visual mismatch negativity (vMMN) component of event-related brain potentials (ERPs). In Experiment 1, within a sequence of stimulus displays with O characters, infrequently presented Q characters elicited an earlier vMMN than did infrequent O characters within a sequence of Q characters. In Experiment 2, similar asymmetric results emerged if only 16 % of the characters were different within an infrequent display. In both experiments, these stimuli were irrelevant; during the stimulus sequences, participants performed a demanding videogame. We suggest that the underlying match/mismatch and decision processes are similar in the vMMN and in the attention-related visual search paradigm, at least in the case of the stimuli in the present experiments.     

Biological markers of cognition in prodromal Huntington's disease: a review

Huntington’s disease (HD), an autosomal-dominant genetic disorder, has historically been viewed as a degenerative movement disorder but it also includes psychiatric symptoms and progressive cognitive decline. There has been a lack of consensus in the literature about whether or not cognitive signs can be detected in carriers before clinical (motor) onset of the disease, i.e., prodromal HD. However, recently validated mathematical formulas to estimate age of clinical onset, refined over the past 5–7 years, have allowed researchers to overcome the methodological limitation of treating all prodromal carriers as a homogenous high-risk group (i.e., whether they may be 2 or 15 years from diagnosis). Here we review 23 articles on the HD prodrome, all of which related cognition to a biological marker of disease burden (i.e., genetic load, neuroimaging). All studies found at least one cognitive domain was associated with disease burden in prodromal HD participants. There was greater variability in both the detection and cognitive domain affected in those farther from onset (or those with less pathology) while most studies reliably found declines in visuomotor performance and working memory in those closer to onset. These findings indicate that cognitive signs can be reliably detected in the HD prodrome when comparing cognition to additional disease markers, however, there continues to be significant variability on cognitive findings among large and methodologically rigorous studies. This may reflect true heterogeneity in the prodromal HD phenotype which must be further explored by analyzing intra-individual variance, determining demographic risk factors associated with decline/protection, and examining if particular HD families exhibit distinct cognitive profiles. These and additional future directions are discussed.     

Mothers' and Fathers' Psychological Symptoms and Marital Functioning: Examination of Direct and Interactive Links with Child Adjustment

A community sample of 51 mother-father dyads with a school-age child rated marital functioning, parental psychological symptoms, and children's adjustment problems. Parents with more psychological symptoms reported lower marital satisfaction levels. Mothers' and fathers' marital functioning and symptomatology individually related to children's adjustment in the expected directions. In addition, interaction tests revealed that, for mothers but not fathers, the combination of poorer marital functioning and higher levels of psychological symptoms amplified the negative effects on children's adjustment problems. These findings support the hypothesis that parental psychopathology and marital adjustment together affect children's functioning in an interactive way, underscoring the need to consider multiple family influences in studies of child development.     

Dogs' (Canis familiaris) responsiveness to human pointing gestures

In a series of 3 experiments, dogs (Canis familiaris) were presented with variations of the human pointing gesture: gestures with reversed direction of movement, cross-pointing, and different arm extensions. Dogs performed at above chance level if they could see the hand (and index finger) protruding from the human body contour. If these minimum requirements were not accessible, dogs still could rely on the body position of the signaler. The direction of movement of the pointing arm did not influence the performance. In summary, these observations suggest that dogs are able to rely on relatively novel gestural forms of the human communicative pointing gesture and that they are able to comprehend to some extent the referential nature of human pointing.     

Problem-solving performance and reproductive success of great tits in urban and forest habitats

Success in problem solving, a form of innovativeness, can help animals exploit their environments, and recent research suggests that it may correlate with reproductive success. Innovativeness has been proposed to be especially beneficial in urbanized habitats, as suggested by superior problem-solving performance of urban individuals in some species. If there is stronger selection for innovativeness in cities than in natural habitats, we expect problem-solving performance to have a greater positive effect on fitness in more urbanized habitats. We tested this idea in great tits (Parus major) breeding at two urban sites and two forests by measuring their problem-solving performance in an obstacle-removal task and a food-acquisition task. Urban pairs were significantly faster problem-solvers in both tasks. Solving speed in the obstacle-removal task was positively correlated with hatching success and the number of fledglings, whereas performance in the food-acquisition task did not correlate with reproductive success. These relationships did not differ between urban and forest habitats. Neophobia, sensitivity to human disturbance, and risk taking in the presence of a predator did not explain the relationships of problem-solving performance either with habitat type or with reproductive success. Our results suggest that the benefit of innovativeness in terms of reproductive success is similar in urban and natural habitats, implying that problem-solving skills may be enhanced in urban populations by some other benefits (e.g. increased survival) or reduced costs (e.g. more opportunities to gain practice with challenging tasks).     

Objectification and System Justification Impact Rape Avoidance Behaviors

There is little recent research on women’s adoption of rape avoidance behaviors, and there has been no known investigation into how adoption of these behaviors relates to various system justification beliefs or experiences of sexual objectification. We surveyed 294 U.S. women aged 18 to 40 to assess experiences of objectification, belief in a just world, gender-specific system justification, benevolent sexism, rape myth acceptance, and engagement in rape avoidance behaviors. Belief in a just world, gender-specific system justification, and benevolent sexism were conceptualized and analyzed as a “system justification” latent factor due to similarities between constructs regarding how they influence worldview, particularly regarding fairness and relations between dominant and subordinate groups. Our hypothesized model had good fit to the data and illustrated that experiencing objectification was related to increased rape myth acceptance and system justification, which, in turn, were related to implementation of rape avoidance behaviors. Further, system justification was significantly positively related to rape myth acceptance. Results show the continued importance of understanding the role of objectification in the endorsement of rape myths and assessments of societal fairness, as well as how women’s attitudes about society may ultimately affect their assessment of rape myths and their personal behavior. This research provides new information and groundwork for researchers developing rape education programming in addition to those interested in the complex relationship between women’s experiences and behavioral outcomes.     

Automatic change detection in vision: Adaptation,memory mismatch,or both? II: Oddball and adaptation effects on event-related potentials

In this study we compared the event-related potentials (ERPs) obtained in two different paradigms: a passive visual oddball paradigm and an adaptation paradigm. The aim of the study was to investigate the relation between the effects of activity decrease following an adaptor (stimulus-specific adaptation) and the effects of an infrequent stimulus within sequences of frequent ones. In Experiment 1, participants were presented with different line textures. The frequent (standard) and rare (deviant) texture elements differed in their orientation. In Experiment 2, windmill pattern stimuli were presented in which the number of vanes differentiated the deviant and standard stimuli. In Experiment 1 the ERP differences elicited between the oddball deviant and the standard were similar to the differences between the ERPs to the nonadapted and adapted stimuli in the adaptation paradigm. In both paradigms the differences appeared as a posterior negativity with the latency of 120–140 ms. This finding demonstrates that the representation of a sequential rule (successive presentation of the standard) and the violation of this rule are not necessary for deviancy effects to emerge. In Experiment 2 (windmill pattern), in the oddball paradigm the difference potentials appeared as a long-lasting negativity. In the adaptation condition, the later part of this negativity (after 200 ms) was absent. We identified the later part of the oddball difference potential as the genuine visual mismatch negativity—that is, an ERP correlate of sequence violations. The latencies of the difference potentials (deviant minus standard) and the endogenous components (P1 and N1) diverged; therefore, the adaptation of these particular ERP components cannot explain the deviancy effect. Accordingly, the sources contributing to the standard-versus-deviant modulations differed from those related to visual adaptation; that is, they generated distinct ERP components.     

Different Associations of Health Related Quality of Life with Pain,Psychological Distress and Coping Strategies in Patients with Irritable Bowel Syndrome and Inflammatory Bowel Disorder

The primary aim of this study was to measure psychological distress, pain severity, health related quality of life (QOL) and pain coping strategies in patients with irritable bowel syndrome (IBS) and ulcerative colitis (UC). A second aim was to determine the influence of somatic and psychological variables on health related QOL. Eighty-eight IBS and 66 UC patients completed the Irritable Bowel Syndrome Quality of Life Questionnaire (IBSQOL), Pain Severity Scale of West Haven Yale Multidimensional Pain Inventory (WHYMPY), Symptom Checklist-90-R (SCL-90-R) and Coping Strategies Questionnaire (CSQ). T-tests and GLM Analysis of Covariance were used for statistical analysis. IBS patients had significantly higher levels of psychological distress, pain severity and maladaptive pain coping strategies (catastrophization), and lower QOL than UC patients. Variance of QOL in IBS was explained for the most part by catastrophization (15%), then by psychological distress (8%), and for the less part by pain severity (5%). In UC, pain severity explained 21%, psychological distress 8%, and catastrophization 3% of the variance of QOL. These results suggest there are differences between IBS and UC patients in the role of physical and psychological factors in QOL and emphasize the importance of cognitive processes in IBS.     

Children and marital conflict resolution: implications for emotional security and adjustment.

This study addresses multiple gaps in understanding the implications of marital conflict resolution for children. Mothers' diary home reports (N = 102 mothers, N = 578 reports) of marital conflict resolution (i.e., compromise, apology, submission, agreement to disagree, withdrawal) and of children's responses, along with the reactions of children (N = 163) to analogue presentations of the same conflict endings in the laboratory, were examined. The significance of specific marital conflict endings, including the emotionality of endings, was supported and demonstrated for the first time in the home. Parents' and children's appraisals of resolution were generally similar, although for some endings these appraisals differed, supporting the notion that children are sensitive to the broader implications of conflict endings for interparental relations and family functioning. Children's responses to conflict resolution were related to their broader adjustment, further indicating the significance of conflict endings to understanding the impact of marital conflict.