Age Influences on Multi-Dimensional Set Switching

Using a task switching paradigm, we investigated age effects on switch costs as a function of the number of sets to be switched. In Experiment 1, younger and older subjects determined a color or shape of an object presented on the computer screen, responding either by moving the joystick or by pressing a button on the joystick. The switch costs were assessed with differences between switch trials (task-set switch, response-set switch, and double switch) and non-switch trials. Contrary to the prediction that age would negatively influence performance on the double switch trials, age effects on switch costs were observed only for the single switch trials (i.e., response-set switch condition). Additionally, both younger and older adults were capable of preparing for task and response-set switches in parallel. In Experiment 2, we manipulated the time available to prepare for a task and response-set switch. Both younger and older adults were able to utilize extra time to reduce switch costs. Furthermore, the age deficit found in Experiment 1 for response-set switching was eliminated in the second experiment in which preparation for task and response-set switching was temporally decoupled. The data are discussed in terms of task component coordination across the adult lifespan.     

Levels of visuo-spatial selection: An ERP study of negative priming

Usually, a probe target appearing in a recently ignored distractor location is less efficiently processed. This robust phenomenon is called (visuo-) spatial negative priming (SNP). Among other explanations, concepts of persisting or retrieved spatial inhibition play a major role. Two relevant issues were investigated using event-related brain potentials (ERPs). The first pertains to context sensitivity of inhibition: Is a probe distractor necessary for SNP? The second concerns levels of processing at which spatial inhibition operates: Does SNP affect perception, selection, and/or stimulus classification? A localization task with and without probe distractors was employed while 64-channel EEG was recorded. Obviously, SNP does not require a probe distractor; the distractor-absent SNP effect was larger than the distractor-present SNP effect. Distractor-present SNP had two lateralized ERP effects, N1pc amplitude reduction and N2pc amplitude increase. Smaller N1pc may indeed reflect perceptual decrement, but was inversely related to size of behavioral SNP. By contrast, only strong-SNP participants showed N2pc increase, which points to selection disadvantage due to persisting inhibition of higher-level spatial representations. Distractor-absent SNP had no N1pc/N2pc correlates; instead, reduced amplitude of a broadly distributed P300 component suggests impaired stimulus classification due to episodic retrieval of inappropriate prime information. Overall, SNP seems to emerge from relatively late stages of processing, thus challenging the idea of context-free persisting inhibition of low-level spatial representations. Furthermore, distractor-present and distractor-absent SNP are qualitatively different from each other.     

Word comprehension and production asymmetries in children and adults

Two studies investigated differences in the comprehension and production of words in 2-year-old children and adults. Study 1 compared children’s speaking and understanding of the names of 12 novel objects presented over three weekly sessions. Study 2 tested adults’ performance under similar training and testing conditions over two sessions. The findings indicated a comprehension advantage for both age groups. A fine-grained temporal analysis of individual words revealed that acquisition does not resemble a linear stage-wise progression from comprehension to production. Rather, dimensions of lexical knowledge develop at different rates, with words acquired, lost, and maintained over the course of learning. The findings support a dynamic and graded view of lexical processing and have implications for understanding what it means to know a word.     

Children's Spatial Behavior is Differentially Affected After Traumatic Brain Injury

Spatial behavior in 20 children with severe traumatic brain injury (TBI) and 20 healthy controls was investigated using the Kiel Locomotor Maze. Children had to remember defined locations in an experimental chamber with completely controlled intra- and extra-maze cues until learning criterion was reached. In a second experiment, spatial orientation strategies were assessed. Children with TBI were shown to be impaired in spatial learning and spatial memory. Spatial orientation was found to be deficient even in cases where spatial learning and memory proved to be unimpaired, especially in tasks that demanded the use of relational place strategies. Children who suffered a TBI at an early age proved to be more severely impaired in spatial learning and orientation than older children.     

Economic Disadvantage and Young Children’s Emotional and Behavioral Problems: Mechanisms of Risk

This study aimed to establish potential mechanisms through which economic disadvantage contributes to the development of young children’s internalizing and externalizing problems. Prospective data from fetal life to age 3 years were collected in a total of 2,169 families participating in the Generation R Study. The observed physical home environment, the provision of learning materials in the home, maternal depressive symptoms, parenting stress, and harsh disciplining practices were all analyzed as potential mediators of the association between economic disadvantage and children’s internalizing and externalizing problem scores. Findings from structural equation modeling showed that for both internalizing and externalizing problems, the mechanisms underlying the effect of economic disadvantage included maternal depressive symptoms, along with parenting stress and harsh disciplining. For internalizing but not for externalizing problem scores, the lack of provision of learning materials in the home was an additional mechanism explaining the effect of economic disadvantage. The current results suggest that interventions that focus solely on raising income levels may not adequately address problems in the family processes that emerge as a result of economic disadvantage. Policies to improve the mental health of mothers with young children but also their home environments are needed to change the economic gradient in child behavior.     

Beyond the heritability of life satisfaction – The roles of personality and twin-specific influences

In a behavior genetic design, we investigated individual differences in life satisfaction and its relation to personality with respect to both internal and external influences. We questioned the absence of shared environment and examined the specific contribution of additive and non-additive genetic influences. We also tested for twin-specific environmental influences in a total sample of 1308 dyads including identical and fraternal twins, siblings, mother–child and grandparent–child pairs. The results showed substantial shared environmental influences on life satisfaction that varied between twins and non-twins, supporting twin-specific environmental influences. Additive and non-additive genetic influences on life satisfaction were completely shared with personality. The remaining variance could be explained by unique non-shared environmental influences for life satisfaction independent of personality.     

Exemplar similarity and rule application

We report four experiments examining effects of instance similarity on the application of simple explicit rules. We found effects of similarity to illustrative exemplars in error patterns and reaction times. These effects arose even though participants were given perfectly predictive rules, the similarity manipulation depended entirely on rule-irrelevant features, and attention to exemplar similarity was detrimental to task performance. Comparison of results across studies suggests that the effects are mandatory, non-strategic and not subject to conscious control, and as a result, should be pervasive throughout categorization.     

Coping With Unemployment: The Impact of Unemployment Duration and Personality on Trajectories of Life Satisfaction

Unemployment is a major life event that causes an enormous drop in people's life satisfaction. However, there is substantial variability in people's ability (or inability) to cope with the experience of unemployment. In the present study, we examined the causes of individual differences in trajectories of life satisfaction when people were faced with unemployment by taking into account the persistence of unemployment, pre‐event personality and age. Analyses were based on data from the German Socio‐Economic Panel. Using latent growth curve modelling, life satisfaction was investigated from 3 years before to 3 years after a person became unemployed in a total sample of 908 individuals. As expected, unemployment caused a substantial drop in life satisfaction that persisted for at least 3 years after the event. On average, individuals did not completely return to their previous satisfaction level. This pattern existed even for participants who re‐entered the labour market. Moreover, our results showed that variability in coping with unemployment can be explained in part by personality traits. For people with short periods of unemployment, Conscientiousness reinforced the negative effect of unemployment, whereas Extraversion softened the effect. In sum, our analyses showed that (a) the negative effect of unemployment on life satisfaction differs according to the length of the unemployment period and (b) personality partially moderates responses to unemployment over time. Copyright © 2015 European Association of Personality Psychology     

A Bayesian approach to the argument from ignorance.

In this paper, we re-examine a classic informal reasoning fallacy, the so-called argumentam ad ignorantiam. We argue that the structure of some versions of this argument parallels examples of inductive reasoning that are widely viewed as unproblematic. Viewed probabilistically, these versions of the argument from ignorance constitute a legitimate form of reasoning; the textbook examples are inductive arguments that are not unsound but simply weak, due to the nature of the premises and conclusions involved. In an experiment, we demonstrated some of the variables affecting the strength of the argument, and conclude with some general considerations towards an empirical theory of argument strength.