Mental simulation of four visual object properties: similarities and differences as assessed by the sentence–picture verification task

In the sentence–picture verification (SPV) task, people read sentences implying the shape/size/colour/orientation of objects. They then verify whether pictured objects, which either match or mismatch the implied visual information mentioned in the sentence. Faster verification times on matching trials (match advantage) are considered supportive to the notion that readers perform mental simulations during sentence comprehension. This study advances this work by applying a within-subjects design to the SPV-task, enabling us to directly address the strength of and correlation between the match advantages for the properties shape, size, colour, and orientation. Results showed varying match advantages with colour showing the strongest effect, and no match advantage for orientation. Shape, size, and colour were significantly correlated, whereas there were no significant correlations with orientation. These findings suggest that interpretations of match advantages could benefit from a re-evaluation of mental simulation accountsby distinguishing between intrinsic (shape, size, and colour) and extrinsic (orientation) object properties.     

Problems with computer games without monetary reward: similarity to pathological gambling

An epidemiological study was performed on a representative sample of the Norwegian youth population (12 to 18 years old, N=3,237; response rate 45.2%). The percentage who were frequent players (weekly) of different computer games was 63.3%, and the percentage of infrequent users was 36.7%. A mean of 2.7% (4.2% of the boys, 1.1% of the girls) could be described as exhibiting "pathological playing" according to the criteria in the 1998 Diagnostic Questionnaire for Internet Addiction of Young, and an additional 9.82% (14.5% of the boys, 5.0% of the girls) were considered to be engaging in "at-risk playing." Of the weekly gamblers, 4.2% fulfilled 5 criteria for pathological playing, and an additional 15.5% 3 to 4 criteria, i.e., at-risk playing. This indicated that frequent gaming on computer games without money rewards may be related to problematic playing even though no monetary reward is involved.     

Internet addiction: characteristics of a questionnaire and prevalence in Norwegian youth (12-18 years)

The use of the Internet has increased considerably during the last few years, and there are also some clinical observations that some people 'get hooked', and develop an Internet addiction. An epidemiological study was performed in a representative sample of the Norwegian youth population (N= 3,237; response rate 45.2%). The proportion not using Internet was only 4.9%, while 35.8% were non-frequent users, and 49.6% (1,591) were frequent (weekly) users. They used the Internet on the mean 4.3 hours a week. A mean of 1.98% (boys 2.42%, girls 1.51%) could be described as having an 'Internet addiction' according to the criteria in the Diagnostic Questionnaire of Young (1998), and an additional 8.68% (in sum 10.66) were considered to have an at-risk Internet use (boys 9.21%, girls 8.13%). If these proportions were calculated on individuals who used the Internet frequently, 4.02% fulfilled 5 criteria, and an additional 17.66% 3-4 criteria, giving quite high figures of problematic Internet use (in sum 21.68). The different diagnostic criteria gave a broad range of affirmative answers (from 0.4% to 27.9%). The results have important implications for further studies of prevalence, implementation of preventive measures, and the development of treatment approaches for Internet addiction.     

Extending in vitro conditioning in Aplysia to analyze operant and classical processes in the same preparation

Operant and classical conditioning are major processes shaping behavioral responses in all animals. Although the understanding of the mechanisms of classical conditioning has expanded significantly, the understanding of the mechanisms of operant conditioning is more limited. Recent developments in Aplysia are helping to narrow the gap in the level of understanding between operant and classical conditioning, and have raised the possibility of studying the neuronal processes underlying the interaction of operant and classical components in a relatively complex learning task. In the present study, we describe a first step toward realizing this goal, by developing a single in vitro preparation in which both operant and classical conditioning can be studied concurrently. The new paradigm reproduced previously published results, even under more conservative and homogenous selection criteria and tonic stimulation regime. Moreover, the observed learning was resistant to delay, shortening, and signaling of reinforcement.     

Activation of midbrain structures by associative novelty and the formation of explicit memory in humans

Recent evidence suggests a close functional relationship between memory formation in the hippocampus and dopaminergic neuromodulation originating in the ventral tegmental area and medial substantia nigra of the midbrain. Here we report midbrain activation in two functional MRI studies of visual memory in healthy young adults. In the first study, participants distinguished between familiar and novel configurations of pairs of items which had been studied together by either learning the location or the identity of the items. In the second study, participants studied words by either rating the words' pleasantness or counting syllables. The ventral tegmental area and medial substantia nigra showed increased activation by associative novelty (first study) and subsequent free recall performance (second study). In both studies, this activation accompanied hippocampal activation, but was unaffected by the study task. Thus midbrain regions seem to participate selectively in hippocampus-dependent processes of associative novelty and explicit memory formation, but appear to be unaffected by other task-relevant aspects.     

Suicidal ideation and attempts in Norwegian police

Studies on suicide among police show inconsistent results, thereby contributing to considerable speculation regarding why police officers commit suicide. The present paper is the first nationwide study on suicidal ideation and attempts among police. 3,272 Norwegian police completed Paykel's Suicidal Feelings in the General Population questionnaire. Lifetime prevalence of specific questionnaire items ranged from 24% for the feeling that life was not worth living, 6.4% for having seriously considered suicide, and 0.7% for attempted suicide. Independent predictors of serious suicidal ideation were marital status, subjective health complaints, reality weakness, anxiety, and depression. Serious suicidal ideation was mainly attributed to personal and family problems.     

Egocentric and geocentric frames of reference in memory of large-scale space

This experiment investigated the frames of reference used in memory to represent the spatial structure of a large-scale outdoor environment. Participants learned the locations of eight objects in an unfamiliar city park by walking through the park on one of two prescribed paths that encircled a large rectangular building. The aligned path was oriented with the building; the misaligned path was rotated by 45°. Later, participants pointed to target objects from imagined vantage points using their memories. Pointing accuracy was higher in the aligned than in the misaligned path group, and the patterns of results differed: In the aligned condition, accuracy was higher for imagined headings parallel to legs of the path and for an imagined heading oriented toward a nearby lake, a salient landmark. In the misaligned condition, pointing accuracy was highest for the imagined heading oriented toward the lake, and decreased monotonically with angular distance. These results indicated that locations of objects were mentally represented in terms of frames of reference defined by the environment but selected on the basis of egocentric experience.     

Can we really reduce ethnic prejudice outside the lab? A meta‐analysis of direct and indirect contact interventions

The present meta‐analysis tested the effectiveness of contact‐based interventions for the reduction of ethnic prejudice. Up to now, a meta‐analysis summarizing the results of real‐world interventions that rest on the intergroup contact theory has been missing. We included evaluations of programs realizing direct (i.e., face‐to‐face) and/or indirect (i.e., extended or virtual) contact in real‐world settings outside the lab. The interventions' effectiveness was tested shortly after their end (k = 123 comparisons, N = 11 371 participants) and with a delay of at least 1 month (k = 25, N = 1650). Our data show that contact interventions improve ethnic attitudes. Importantly, changes persist over time. Furthermore, not only direct but also indirect contact interventions are successful. In addition, contact programs are effective even in the context of a serious societal conflict (e.g., in the Middle East). Although changes are typically larger for ethnic majorities, there is an impact on minorities, too. Finally, contact interventions not only improve attitudes toward individuals involved in the program, their effects also generalize to outgroups as a whole. In sum, social psychology provides an intervention for prejudice reduction that can be successfully implemented in the practical field. Copyright © 2015 John Wiley & Sons, Ltd.