Age-related differences in the visual processes implied in perception and action: distance and location parameters

The aim of the two present experiments was to examine the ontogenetic development of the dissociation between perception and action in children using the Duncker illusion. In this illusion, a moving background alters the perceived direction of target motion. Targets were held stationary while appearing to move in an induced displacement. In Experiment 1, 30 children aged 7, 9, and 12 years and 10 adults made a perceptual judgment or pointed as accurately as possible, with their index finger, to the last position of the target. The 7-year-old children were more perceptually deceived than the others by the Duncker illusion but there were no differences for the goal-directed pointing movements. In Experiment 2, 50 children aged 7, 8, 9, 10, and 11 years made a perceptual judgment or reproduced as accurately as possible, with a handle, the distance traveled by the target. Participants were perceptually deceived by the illusion, judging the target as moving although it was stationary. When reproducing the distance covered by the target, children were unaffected by the Duncker illusion. Our results suggest that the separation of the allocentric visual perception pathway from the egocentric action pathway occurs before 7 years of age.     

Selective search for conjunctively defined targets by children and young adults

Two experiments were conducted to investigate age-related differences in visual search for targets defined by the conjunction of two features. In the experiments, 7- and 10-year-old children and young adults searched visual displays for a black circle among distractors consisting of gray circles and black squares. In Experiment 1 (N = 60), we compared performance in the standard search task (where an equal number of each type of distractor appeared across all display sizes) with performance in a modified search task (where the number of black squares was fixed at two and the number of gray circles increased as the display size increased). In Experiment 2 (N = 60), the ratio of black stimuli to gray stimuli was varied systematically as the display size increased. Results of both experiments indicated that all participants were able to restrict search to an appropriate subset of the display rather than conduct an exhaustive search. However, the young adults were more efficient in their ability to do so than were either the 7- or 10-year-old participants. The 10-year-olds were as efficient as the young adults when the number of black stimuli in the display was relatively small. However, these children became relatively less able to restrict search effectively as the number of black stimuli increased. Discussion focused on possible preattentive and attentive processes that may change systematically with age.     

New Factor Structure of the Interpretation of Intrusions Inventory with University Students

The Obsessive Compulsive Cognitions Working Group (OCCWG) created the Interpretation of Intrusions Inventory (III) to measure appraisals (interpretations) of mental intrusions. Validation attempts by the OCCWG suggest that the three appraisal mechanisms hypothesized to comprise the III are better described as a single construct. The underlying factor structure of the III was investigated with university students (n = 307). Confirmatory factor analyses were conducted on the theoretically-derived three-factor model and on the empirically-derived one-factor model of the III. Both models failed to adequately fit the data. Thus, an exploratory factor analysis was conducted, which produced a two-factor model consisting of appraisals of Responsibility and Importance/Control of Thoughts. The new factors exhibited good predictive validity, as they predicted the severity of obsessive-compulsive symptoms and subtypes of obsessive-compulsive disorder (OCD).

A Comparison of Stress Measures in Children and Adolescents: A Self-Report Checklist Versus an Objectively Rated Interview

A self-report checklist assessing the occurrence of stressful life events in children and adolescents' lives was compared to an objectively rated interview to determine whether the checklist would introduce over-reporting of events or over-rating of event severity as a function of child/parent depressive symptoms, cognitive vulnerability, or anxiety. Participants completed the Children's Life Events Scale (CLES), the Life Events Interview (LEI), and questionnaires assessing cognitive vulnerability and symptoms of depression and anxiety. Findings yielded a positive association between the checklist and the interview. Contrary to hypotheses, depressive symptoms, cognitive vulnerability, and anxiety were not associated with over-reporting of events. Anxiety was associated with over-rating of event severity in parents but not children. Findings suggest that the checklist and interview may be equally viable approaches to assessing the occurrence of life events. Findings have mixed implications with regard to assessing event severity, as subjective reports may be systematically influenced by anxiety.

Hairpulling and Skin Picking in Relation to Affective Distress and Obsessive-Compulsive Symptoms

The current study examined the frequency and associated distress of both hairpulling and skin picking behaviors in 1,324 college students using the Massachusetts General Hospital Hairpulling Scale (MGHHS) and Skin Picking Scale (SPS). In this sample, many participants reported significant distress secondary to both hairpulling and skin picking. Participants who endorsed relatively frequent hairpulling or skin picking (N = 72) were scheduled for a follow-up testing session to further assess the relationship between these behaviors and measures of affective distress. Compared to a control sample, the follow-up sample endorsed significantly more symptoms of anxiety and stress reactivity, and had higher scores on a measure of obsessive-compulsive symptoms.

Internetchatgruppen in Psychotherapie und Psychosomatik

Zusammenfassung  In Zusammenarbeit mit der Techniker Krankenkasse (TK) und der Panorama-Fachklinik für Psychosomatik, Psychotherapeutische Medizin und Naturheilverfahren Scheidegg/Allgäu hat die Forschungsstelle für Psychotherapie das Projekt Internetbrücke initiiert. Die Patienten erhielten im Anschluss an ihre stationäre Behandlung das Angebot, für 12–15 Wochen an einer Gruppe teilzunehmen, die sich in einem speziell eingerichteten Chatraum wöchentlich traf. Das Projekt hatte die Ziele: (a) eine geeignete Internetumgebung für eine vertrauliche Kommunikation aufzubauen und deren Praktikabilität zu testen sowie (b) die Akzeptanz durch die Patienten und die Wirksamkeit zu evaluieren. Zur Evaluation wurde eine prospektive kontrollierte Studie durchgeführt. Chatteilnehmer (n=114) wurden mit einer gematchten Vergleichsgruppe (n=114) hinsichtlich ihres Gesundheitszustands ein halbes Jahr nach der Klinikentlassung verglichen. Die Technik erwies sich als robust und nutzerfreundlich. Das Angebot wurde sehr positiv von den Patienten aufgenommen; dies drückte sich u. a. in der niedrigen Abbruchrate (9,4%) und der hohen Akzeptanz (83,7% der Chatteilnehmer hielten eine Internetbrücke für sinnvoll) aus. Die Chatteilnehmer konnten die während der stationären Behandlung erreichten positiven Entwicklungen – gemessen mit dem globalen Kriterium der Stuttgart-Heidelberger Qualitätssicherung – besser erhalten als die Vergleichsgruppe (p<0,05). Es zeigten sich Vorteile für die Chatteilnehmer im Hinblick auf das psychische Befinden, während die Unterschiede im körperlichen Befinden eher gering waren. Die Konsequenzen für die psychosoziale Versorgung werden diskutiert.

On the fate of distractor stimuli in rapid serial visual presentation

Observers demonstrate an impaired ability to report the second of two targets in a rapid serial visual presentation (RSVP) stream if it appears within 500 ms of the first target--a phenomenon known as the attentional blink. This study investigated the fate of stimuli in dual-target RSVP streams that do not require report--the distractors. In five experiments, observers viewed dual-target RSVP streams where the items flanking Target 1 either had the same identity (repeats) or a different identity (non-repeats). Repeated distractors reduced the attentional blink, but only if two conditions were met (1) the items flanking Target 1 were featurally identical and (2) the distractors were drawn from a different alphanumeric category to the targets (e.g. digits vs. letters). We interpret this reduced blink magnitude in the repeat trials as evidence that in RSVP streams distractor items that appear in close temporal proximity to Target 1 are inhibited and we propose that this inhibition occurs both at the level of alphanumeric features and abstract identities.     

Time course of attentional bias for fear-relevant pictures in spider-fearful individuals

The time course of attentional biases for spider stimuli was assessed in two groups of individuals with high or low levels of spider fear. Pairs of photographs of spiders and cats were presented in a visual probe task with three exposure durations: 200, 500 and 2000 ms. Results indicated greater attentional bias for spider stimuli in high fear, than in low fear, individuals in the 200 ms condition. The attentional bias in the high fear group significantly reduced as stimulus exposure duration increased, with no significant biases found in the longer exposure conditions. Results support the view that high fear is associated with an enhanced initial attentional bias for fear-relevant stimuli, but that this attentional bias is not maintained over time.