Detection of temporal order of noise-like luminance functions

We study the capacities of human observers to time order light sources that emit dynamic noise, identical for the different light sources, except for an adjustable delay. There is a range of temporal delays for which human observers are perfectly able to perform this task, using the direction of the motion percept that is evoked by the stimulus as a cue. An optimal delay between light sources at which the observers are most robust against any deterioration of the stimulus is defined. We claim that optimal delays (15–25 msec) correspond to the time delay of a putative Reichardt correlation mechanism in human motion vision. Contrary to the ability of human observers to sense temporal correlations in noise sequences, observers are totally unable to detect anticorrelation between noise sequences. This inability rules out motion opponency as a viable model for human front-end (“early”) motion vision.     

Discrepancies between patients' and partners' perceptions of unsupportive behavior in chronic obstructive pulmonary disease

The literature on chronic diseases indicates that partner support, as perceived by patients, contributes to well-being of patients in either a positive or a negative way. Previous studies indicated that patients' and partners' perceptions of unsupportive partner behavior are only moderately related. Our aim was (1) to investigate whether discrepancies between patients' and partners' perceptions of two types of unsupportive partner behavior-overprotection and protective buffering-were associated with the level of distress reported by patients with chronic obstructive pulmonary disease (COPD) and (2) to evaluate whether the direction of the differences between patients' and partners' perceptions was associated with distress (i.e., whether patient distress was associated with greater patient or greater partner reports of unsupportive partner behavior). A cross-sectional study was performed using the data of a sample of 68 COPD patients and their spouses. Distress was assessed using the Hopkins Symptom Checklist-25. Patients' and partners' perceptions of unsupportive partner behavior were assessed with a questionnaire measuring overprotection and protective buffering. Distress was independently associated with patients' perceptions of protective buffering and discrepancies in spouses' perceptions of overprotection. Regarding the direction of the discrepancy, we found that greater partner reports of overprotection as compared with patient reports were related to more distress in COPD patients. Our study showed that patients' distress was associated not only with patients' perceptions, but also with discrepancies between patients' and partners' perceptions of unsupportive partner behavior.     

Social behaviour and social cognition in high-functioning adolescents with autism spectrum disorder (ASD): two sides of the same coin?

Of the triad of symptoms found in autism spectrum disorder (ASD), that is, social impairments, communication difficulties and repetitive interests and behaviour, the social impairments are the most stable and common throughout the lifespan. They typically manifest themselves in abnormalities as reciprocal interactions and difficulties in the expression and recognition of emotions. Although peer interactions become especially important during adolescence, little is known about the mentalizing abilities of high-functioning adolescents with ASD. Here, we compared the mentalizing skills and emotion recognition abilities of 21 high-functioning adolescents with ASD and 21 matched controls. All adolescents had estimated above-average verbal intelligence levels. Spontaneous social abilities and task-related social abilities were measured using questionnaires, tasks and the Autism Diagnostic Observation Schedule. Results confirm social impairment in daily life situations in adolescents with ASD, but were not found on experimental tasks of social cognition. The use of more explicit cognitive or verbally mediating reasoning techniques and a lesser tendency of high-functioning adolescents with ASD to search for and use social information in natural environments are further discussed.