Geometrical illusions in solid objects under ordinary viewing conditions

The Müller-Lyer and Ponzo illusions were obtained under free binocular viewing of three-dimensional objects, and the function relating magnitude of illusion to fin angle, characteristic of converging-line versions of the Müller-Lyer pattern, was closely paralleled by volumetric (three-cone), line-free objects (but not with an erect, planar “walk-through” construction and moving observers). Illusions cannot be dismissed as artifacts of static, impoverished viewing, therefore, but must be explained within any general theory of perception. Perspective explanations have difficulties with such three-dimensional manifestations, and seem completely inapplicable to our further finding that approximately the same amount of illusion occurred in objects and patterns with no oblique lines or edges. Confusion or averaging theories, not themselves tested here, remain unthreatened by these data.     

Expansion strategies of a mutual help organization

Described a study of the expansion strategies of a successful self- and mutual help organization for persons with mental illness. Resource mobilization and behavior-setting theories were used as conceptual frameworks to guide the investigation. Collaborative methods and a grounded theory approach were used. Archives, reports of contacts outside of the organization, and naturalistic observations were data sources. Of particular interest are the processes used by the organization to mobilize internal and external resources and to start new mutual help groups. Results suggest that the organization mobilizes resources from a variety of sources, displays flexibility in securing resources and defining organizational roles, and creates underpopulated settings to encourage individual involvement. The strategies appear to avoid overtaxing resource pools, reduce role ambiguity, and encourage pluralistic participation. Discussion includes several potential explanations for the successful growth of the organization.     

Measuring post-traumatic stress: A psychometric evaluation of symptom- and coping questionnaires based on a Norwegian sample

The purpose of this study was to evaluate the psychometric characteristics of the Norweigian versions of the Impact of Event Scale, the Post Traumatic Stress Scale-10 item version and General Coping Questionnaire-30 item version. A group of 40 male and 56 female medical students was tested one week and four months after having started dissection of cadavers for the first time. The results showed that all scales had good internal consistency and test-retest reliability. The student sample scored lower on the IES and PTSS-10 than comparable groups of traumatized subjects. A gender difference emerged, with female subjects scoring higher than male subjects. The factor analysis of the instruments indicated good construct validity for the symptom scales. The analysis of content validity related to DSM IV criteria indicated that the IES and PTSS-10 may have some limitations in their predictive validity of PTSD. Taken together, the three scales have shown good psychometric properties and could be used in future research and clinical work.     

The Processing of Grammatical Gender and Number in Spanish

The aim of the present study is to explore the representation and processing of inflectional morphology in Spanish. Experiment 1 compared the access time for words from the same base morpheme contrasted by the surface frequency of the masculine and feminine form, i.e., masculine-dominant items and feminine-dominant items. The results showed a surface frequency effect in both types of items. Experiment 2 compared the access time for masculine words having the same surface frequency but differing in their summed frequency (masculine plus feminine forms), the results showing no significant effect of this parameter. Finally, experiment 3 compared the access time for words from the same stem and contrasting by the surface frequencies for the singular and plural forms, i.e., singular-dominant and plural-dominant words. A clear frequency effect was observed for the singular-dominant words but not for plural-dominant ones. These results suggest that gender information is stored in the corresponding lexical entry and accessed from the full word form whereas the information about number is accessed from the stem corresponding to the singular form.     

Giving and Receiving Help: Interpersonal Transactions in Mutual-Help Meetings and Psychosocial Adjustment of Members

The helping transactions that occur in group meetings have been theorized to be important therapeutic mechanisms within mutual-help (or self-help) groups. Hypothesized links between giving and receiving help and psychosocial adjustment were examined in a mutual-help group for individuals with serious mental illness (GROW). Participants' adjustment was assessed at two time points and helping behaviors were measured with observational coding of weekly group interactions during the period between assessments. Frequencies of helping behaviors were used to predict Time 2 adjustment after controlling for initial adjustment. Consistent with the helper therapy principle, giving help to others predicted improvements in psychosocial adjustment; giving advice was a unique predictor. Total amount of help received was not associated with adjustment, but receiving help that provided cognitive reframing was associated with better social adjustment. A predicted interaction suggested that receiving help was related to better functioning when members experienced high levels of group integration.     

A method for measuring eye movements using Hall-effect devices

A system for precise recording of eye position and movements in laboratory animals, by means of Hall-effect devices, is described. The system, useful in neurophysiological and neurobehavioral studies, allows the analysis of saccadic eye movements, optokinetic- and vestibular-induced nystagmus, slow tracking movements, eye vergences, and so forth. This small, light-weight, and inexpensive system uses a set of Hall-effect devices and associated electronics to sense variations in the position of high-power magnets fixed in the eye sclera or in scleral contact lenses. The output of the Hall-effect devices is amplified by operational amplifiers, collected through an A/D converter, and analyzed in a PC computer by specific software.     

Dimensions of interpersonal orientation: Cross-cultural studies regarding the structure of the ‘DOI Kit’

The DOI Kit is a four-version instrument (Junior Self and Other-Report, and Adult Self-and Other-Report) developed in Spain to measure ‘Dimensions of Interpersonal Orientation’ (Spanish: ‘Dimensiones de Orientación Interpersonal’ or DOI), which are defined as prevalent postures in interpersonal behaviour. The DOI Kit has six first-level scales that collapse into two broad oblique dimensions: Prosocial versus Antisocial Behaviour, and Sociability versus Unsociability.The aim of this article is to find out whether the first- and second-level structure of the Spanish DOI Kit can also be applied to data gathered in Chile and in Germany. A total of eight groups of data were studied. In order to find the best common structure for Spanish, Chilean, and German samples, Simultaneous Component Analysis (SCA) was applied. SCA shows an excellent replication of the original DOI Kit structure. This is also found when separate factor analyses (varimax and oblimin rotations) are performed.     

Simulating naturalistic demands for speeded judgment

Responses to speeded judgment (e.g., “shoot/don’t shoot”) situations in naturalistic environments are influenced by many variables and psychological processes. We describe a custom-built simulator with head- and eye-tracking capabilities for basic and applied research on speeded decision making. The system allows the user to project life-sized, time-coded, videotaped, or computer-animated scenarios on a screen to collect reaction-time, shot-accuracy, and eye-movement data. An initial experiment is also reported to demonstrate the utility of the system for studying factors that affect speeded judgment under naturalistic situations.