Agreement between Parents and Children on Ratings of Post-Concussive Symptoms Following Mild Traumatic Brain Injury

The level of parent-child agreement on post-concussive symptoms (PCS) was examined in children following mild traumatic brain injuries (TBI). As part of a larger longitudinal study, 186 children with mild TBI and 99 with orthopedic injuries (OI), from 8 to 15 years of age, were recruited prospectively. Parents and children completed the PCS Interview (PCS-I) and the Health and Behavior Inventory (HBI) at 2 weeks, 1 month, 3 months, and 12 months postinjury. Item-level correlations between child and parent ratings on both measures of PCS were significant but modest in both groups. Parent-child correlations for composite scales on the HBI and the total score on the PCS-I were significant in both groups, but somewhat higher in the OI group than in the mild TBI group. Mean symptom ratings tended to be significantly higher for children as compared to parents, especially for somatic symptoms. Parents and children display modest agreement when reporting PCS; their ratings correlate significantly, but children report higher mean levels of symptoms than parents.     

Reasons for (prior) belief in Bayesian epistemology

Bayesian epistemology tells us with great precision how we should move from prior to posterior beliefs in light of new evidence or information, but says little about where our prior beliefs come from. It offers few resources to describe some prior beliefs as rational or well-justified, and others as irrational or unreasonable. A different strand of epistemology takes the central epistemological question to be not how to change one’s beliefs in light of new evidence, but what reasons justify a given set of beliefs in the first place. We offer an account of rational belief formation that closes some of the gap between Bayesianism and its reason-based alternative, formalizing the idea that an agent can have reasons for his or her (prior) beliefs, in addition to evidence or information in the ordinary Bayesian sense. Our analysis of reasons for belief is part of a larger programme of research on the role of reasons in rational agency (Dietrich and List, Nous, 2012a, in press; Int J Game Theory, 2012b, in press).     

Positive emotion broadens attention focus through decreased position-specific spatial encoding in early visual cortex: Evidence from ERPs

Recent evidence has suggested that not only stimulus-specific attributes or top-down expectations can modulate attention selection processes, but also the actual mood state of the participant. In this study, we tested the prediction that the induction of positive mood can dynamically influence attention allocation and, in turn, modulate early stimulus sensory processing in primary visual cortex (V1). High-density visual event-related potentials (ERPs) were recorded while participants performed a demanding task at fixation and were presented with peripheral irrelevant visual textures, whose position was systematically varied in the upper visual field (close, medium, or far relative to fixation). Either a neutral or a positive mood was reliably induced and maintained throughout the experimental session. The ERP results showed that the earliest retinotopic component following stimulus onset (C1) strongly varied in topography as a function of the position of the peripheral distractor, in agreement with a near–far spatial gradient. However, this effect was altered for participants in a positive relative to a neutral mood. On the contrary, positive mood did not modulate attention allocation for the central (task-relevant) stimuli, as reflected by the P300 component. We ran a control behavioral experiment confirming that positive emotion selectively impaired attention allocation to the peripheral distractors. These results suggest a mood-dependent tuning of position-specific encoding in V1 rapidly following stimulus onset. We discuss these results against the dominant broaden-and-build theory.     

Pressure to cooperate: Is positive reward interdependence really needed in cooperative learning?

Background. Despite extensive research on cooperative learning, the debate regarding whether or not its effectiveness depends on positive reward interdependence has not yet found clear evidence. Aims. We tested the hypothesis that positive reward interdependence, as compared to reward independence, enhances cooperative learning only if learners work on a ‘routine task’; if the learners work on a ‘true group task’, positive reward interdependence induces the same level of learning as reward independence. Sample. The study involved 62 psychology students during regular workshops. Method. Students worked on two psychology texts in cooperative dyads for three sessions. The type of task was manipulated through resource interdependence: students worked on either identical (routine task) or complementary (true group task) information. Students expected to be assessed with a Multiple Choice Test (MCT) on the two texts. The MCT assessment type was introduced according to two reward interdependence conditions, either individual (reward independence) or common (positive reward interdependence). A follow‐up individual test took place 4 weeks after the third session of dyadic work to examine individual learning. Results. The predicted interaction between the two types of interdependence was significant, indicating that students learned more with positive reward interdependence than with reward independence when they worked on identical information (routine task), whereas students who worked on complementary information (group task) learned the same with or without reward interdependence. Conclusions. This experiment sheds light on the conditions under which positive reward interdependence enhances cooperative learning, and suggests that creating a real group task allows to avoid the need for positive reward interdependence.     

Cognitive model decomposition of the BART: Assessment and application

The Balloon Analogue Risk Task, or BART, aims to measure risk taking behavior in a controlled setting. In order to quantify the processes that underlie performance on the BART, Wallsten, Pleskac, and Lejuez (2005) proposed a series of mathematical models whose parameters have a clear psychological interpretation. Here we examine a 2-parameter simplification of Wallsten et al.’s preferred 4-parameter model. A parameter recovery study shows that — with plausible restrictions on the number of participants and trials — both parameters (i.e., risk taking γ⁺ and response consistency β) can be estimated accurately. To demonstrate how the 2-parameter model can be used in practice, we implemented a Bayesian hierarchical version and applied it to an empirical data set in which participants performed the BART following various amounts of alcohol intake.     

The education of attention as explanation of variability of practice effects: learning the final approach phase in a flight simulator

The present study reports two experiments in which a total of 20 participants without prior flight experience practiced the final approach phase in a fixed-base simulator. All participants received self-controlled concurrent feedback during 180 practice trials. Experiment 1 shows that participants learn more quickly under variable practice conditions than under constant practice conditions. This finding is attributed to the education of attention to the more useful informational variables: Variability of practice reduces the usefulness of initially used informational variables, which leads to a quicker change in variable use, and hence to a larger improvement in performance. In the practice phase of Experiment 2 variability was selectively applied to some experimental factors but not to others. Participants tended to converge toward the variables that were useful in the specific conditions that they encountered during practice. This indicates that an explanation for variability of practice effects in terms of the education of attention is a useful alternative to traditional explanations based on the notion of the generalized motor program and to explanations based on the notions of noise and local minima.     

The beneficial and detrimental effects of major depression on intuitive decision-making

Intuitions play a central role in everyday life decision-making but little is known regarding this capacity during depression. Thus, in Study 1, N?=?39 depressed in-patients completed two well-established tasks, assessing intuitions of visual and semantic coherence. In the semantic coherence task, patients judged whether presented words triads were coherent (e.g. SALT DEEP FOAM, related to SEA) or not (e.g. DREAM BALL BOOK, no denominator). In the visual coherence task, patients judged whether blurred pictures depicted real-life objects (coherent) or not (incoherent). Results showed that higher depressive symptomatology was associated with impaired intuitions of semantic coherence but with enhanced intuitions of visual coherence. In Study 2, visual coherence intuitions of depressed patients (n?=?27) were compared to healthy control participants (n?=?30). Depressed patients outperformed the healthy control subjects in the visual coherence task. This pattern of findings shows both detrimental and beneficial decisional consequences of depression.     

Prospective memory: Are preparatory attentional processes necessary for a single focal cue?

The preparatory attentional and memory processes theory of prospective memory (PM) assumes that PM retrieval requires resource-demanding preparatory attentional processes, whereas the multiprocess theory assumes that retrieval can also occur spontaneously. On the basis of showing slowing on an ongoing task (i.e., task interference) —even when the PM cue was highly salient (i.e., the participant’s own name) —Smith, Hunt, McVay, and McConnell (2007) concluded that preparatory attentional processes are always necessary for PM retrieval. We argue that the presence of preparatory attentional processes cannot be used to rule out the existence of spontaneous retrieval processes, and the goal of the present research was to examine whether PM retrieval can occur in the absence of preparatory attentional processes. We varied whether we emphasized the importance of the PM task or the ongoing task, and we assessed task interference across quarters of the ongoing task. Our results showed no evidence of task interference and, hence, no evidence of preparatory attentional processes in the periods proximal to the target event, and yet participants showed high PM performance. Thus, the results suggest the existence of spontaneous retrieval processes and support the multiprocess theory.