Aging and the perception of depth and 3-D shape from motion parallax

The ability of younger and older observers to perceive 3-D shape and depth from motion parallax was investigated. In Experiment 1, the observers discriminated among differently curved 3-dimensional (3-D) surfaces in the presence of noise. In Experiment 2, the surfaces' shape was held constant and the amount of front-to-back depth was varied; the observers estimated the amount of depth they perceived. The effects of age were strongly task dependent. The younger observers' performance in Experiment 1 was almost 60% higher than that of the older observers. In contrast, no age effect was obtained in Experiment 2. Older observers can effectively perceive variations in depth from patterns of motion parallax, but their ability to discriminate 3-D shape is significantly compromised.     

Exploring the Generalization Process from Past Behavior to Predicting Future Behavior

Substantial evidence in social psychology documents that traits predict behavior. Research in behavioral economics establishes prior behavioral information—the actual behavior of another person in the past—influences future decision making, suggestive of the role of traits in guiding future behavior, but agnostic to the specific psychological mechanism. Yet the entire generalization process from past behavior to predicting future behavior has not been fully explored. Additionally, previous paradigms do not adequately dissociate prediction from explanation, and provide participants with trait information, or rely on participants to generate the appropriate trait. Here, we combine literature and experimental approaches in social psychology and behavioral economics to explore the generalization process from prior behavior that guides future decisions. Across three studies utilizing consequential economic game paradigms and online questionnaires, an initial group of participants (employees) played a time estimation game and a charity donations game before a second group of participants (employers) viewed the behavior of the first group, then decided whether to invest in employees in a trust game and rock guessing game. Although participants infer trait warmth and competence from the behavioral information in the first two games, estimates of normative behavior predicted investment decisions on the warmth‐relevant games better than trait inferences. These results dissociate generalizations guided by warmth and competence behavioral information, and question the extent to which traits always serve as heuristics to predict behavior. Copyright © 2015 John Wiley & Sons, Ltd.     

Performance Effects of Reward-Related Feedback on the Dimensional Change Card Sort Task

The Dimensional Change Card Sort (DCCS) is one of the most widely used measures of preschool executive function, yet relatively little is known about how altering emotional demands of the task affects DCCS performance. This study examined the effects of emotionally evocative reward-related feedback on preschool children's performance on the DCCS in a sample of 105 children aged 3.5–4.5 years. In a within-subjects design, children completed the standard DCCS and a modified version of the DCCS in which sticker rewards were gained or lost after each trial. With a reward at stake, children were more accurate but had slower reaction time on the post-switch DCCS. Another sample (N = 20) of 3.5- to 4.5-year-olds who completed the standard DCCS twice without reward showed no change in performance, indicating results are not due to practice effects. Findings demonstrate preschool children's ability to adjust their approach to the DCCS in the presence of emotionally evocative reward-related feedback by prioritizing accuracy over speed. Trial-by-trial reward-related feedback may facilitate cognitive control in early childhood.     

Adaptive memory: the comparative value of survival processing

We recently proposed that human memory systems are "tuned" to remember information that is processed for survival, perhaps as a result of fitness advantages accrued in the ancestral past. This proposal was supported by experiments in which participants showed superior memory when words were rated for survival relevance, at least relative to when words received other forms of deep processing. The current experiments tested the mettle of survival memory by pitting survival processing against conditions that are universally accepted as producing excellent retention, including conditions in which participants rated words for imagery, pleasantness, and self-reference; participants also generated words, studied words with the intention of learning them, or rated words for relevance to a contextually rich (but non-survival-related) scenario. Survival processing yielded the best retention, which suggests that it may be one of the best encoding procedures yet discovered in the memory field.     

Control, denial, and heightened sensitivity reactions to personal threat: testing the generalizability of the threat orientation approach

The threat orientation model proposes three dispositional responses to threats: control, heightened sensitivity, and denial. Two studies explored the psychometric properties of the previously developed threat orientation scales and the relationship between the orientations and the responses to a variety of threats. Study 1 found that the control-based and heightened sensitivity-based scales are reliable and were related to perceptions of health, financial, and terrorist threats with a nationally representative sample. Findings held across gender, age, and ethnic groups. Furthermore, Study 1 suggested two types of denial processes: optimistic denial and avoidance denial. Study 2 used a diverse sample to gain additional evidence for two processes of denial and developed measures of each type.     

Not all emotions are created equal: the negativity bias in social-emotional development

There is ample empirical evidence for an asymmetry in the way that adults use positive versus negative information to make sense of their world; specifically, across an array of psychological situations and tasks, adults display a negativity bias, or the propensity to attend to, learn from, and use negative information far more than positive information. This bias is argued to serve critical evolutionarily adaptive functions, but its developmental presence and ontogenetic emergence have never been seriously considered. The authors argue for the existence of the negativity bias in early development and that it is evident especially in research on infant social referencing but also in other developmental domains. They discuss ontogenetic mechanisms underlying the emergence of this bias and explore not only its evolutionary but also its developmental functions and consequences. Throughout, the authors suggest ways to further examine the negativity bias in infants and older children, and they make testable predictions that would help clarify the nature of the negativity bias during early development.     

Psychological trauma and schizotypal personality disorder

Two studies examined the relation between psychological trauma and schizotypal symptoms. In Study 1, in which 1,510 adults completed telephone interviews, both childhood maltreatment and the experience of an injury or life-threatening event were significantly associated with schizotypal symptoms. In Study 2, in which 303 adults (oversampled for having elevated levels of schizotypal symptoms) completed extensive in-person assessments, both childhood maltreatment and meeting posttraumatic stress disorder (PTSD) Criterion A were significantly associated with schizotypal symptoms. The links between schizotypal symptoms and at least some forms of psychological trauma could not be fully accounted for by shared variance with antisocial and borderline personality disorders, absorption/dissociation, PTSD symptom severity, family history of psychotic disorder, or signs of neurodevelopmental disturbance (as indexed by minor physical anomalies and inconsistent hand use). Schizotypal symptoms were more strongly associated with childhood maltreatment among men than among women, whereas schizotypal symptoms were more strongly associated with PTSD Criterion A among women than among men. Finally, among men, the association between childhood maltreatment and schizotypal symptoms was moderated by signs of neurodevelopmental disturbance.     

The Effects of Hurricane Katrina on Females with a Pre-Existing Fear of Storms

The purpose of this study was to determine the effects of Hurricane Katrina on those with preexisting storm fear. Participants were divided into two groups, those with a fear of storms and control participants with no reported fears of any specific stimuli. Differences were examined on measures of exposure to and distress from trauma, fear, coping self-efficacy, and demographic variables. The participants were 62 female undergraduate college students who completed an online survey examining the effects of Hurricane Katrina. Despite no differences in the overall occurrence of trauma between the two groups, storm-fearful participants reported significantly more overall distress from their exposure when compared to the non-fearful participants. Those with storm-fears also reported significantly poorer coping self-efficacy following the storm than those who were not fearful. Overall, individuals with a fear of storms reported experiencing greater psychological impact and poorer coping self-efficacy from the same degree of storm exposure.     

Pigeons' discounting of probabilistic and delayed reinforcers

Pigeons' discounting of probabilistic and delayed food reinforcers was studied using adjusting-amount procedures. In the probability discounting conditions, pigeons chose between an adjusting number of food pellets contingent on a single key peck and a larger, fixed number of pellets contingent on completion of a variable-ratio schedule. In the delay discounting conditions, pigeons chose between an adjusting number of pellets delivered immediately and a larger, fixed number of pellets delivered after a delay. Probability discounting (i.e., subjective value as a function of the odds against reinforcement) was as well described by a hyperboloid function as delay discounting was (i.e., subjective value as a function of the time until reinforcement). As in humans, the exponents of the hyperboloid function when it was fitted to the probability discounting data were lower than the exponents of the hyperboloid function when it was fitted to the delay discounting data. The subjective values of probabilistic reinforcers were strongly correlated with predictions based on simply substituting the average delay to their receipt in each probabilistic reinforcement condition into the hyperboloid discounting function. However, the subjective values were systematically underestimated using this approach. Using the discounting function proposed by Mazur (1989), which takes into account the variability in the delay to the probabilistic reinforcers, the accuracy with which their subjective values could be predicted was increased. Taken together, the present findings are consistent with Rachlin's (Rachlin, 1990; Rachlin, Logue, Gibbon, & Frankel, 1986) hypothesis that choice involving repeated gambles may be interpreted in terms of the delays to the probabilistic reinforcers.