Determining Cannabis Use Status From a Photograph: An Assessment of the "Jay-dar" in Neuropsychologists.

BACKGROUND: Few studies examining the cognitive effects of chronic cannabis use utilize research designs where examiners are blind to user status. Even in those that do, researchers may be able to guess the user status of participants, leaving these studies vulnerable to the expectancy effect confound. OBJECTIVES: The present study examined the ability of neuropsychologists (those who would conduct research on the cognitive effects of cannabis) to differentiate cannabis users and nonusers based on physical appearance from photographs. METHOD: We recruited 84 participants from an international neuropsychology listserv. The sample was 59.5% female and 95.2% Caucasian, with a mean age of 41.39 years (range 26-65). Each neuropsychologist rated 25 target faces (12 cannabis users, 13 nonusers) on a Marijuana Use Likelihood Index based upon individuals' photographs. RESULTS: Results indicate a main effect of user group, as neuropsychologists ascribed higher ratings to cannabis users on the Marijuana Use Likelihood Index, suggesting they perceive them as more likely to be users, relative to nonusers. Results also demonstrated a main effect of gender, as males received higher user ratings than females, and a significant main effect of rater gender, as female raters were more likely to rate individuals as cannabis users relative to male raters. Conclusions/Importance: The results demonstrate the importance of assessing researchers' expectations when studying the effects of chronic cannabis use, as even those designs that keep examiners blind to participant user status may be vulnerable to expectancy effects if examiners are able to guess user status based upon appearance alone.

Anorexia nervosa and bulimia nervosa: A meta-analysis of executive functioning.

OBJECTIVE: Research investigating the link between eating disorder (ED) diagnosis and executive dysfunction has had conflicting results, yet no meta-analyses have examined the overall association of ED pathology with executive functioning (EF). METHOD: Effect sizes were extracted from 32 studies comparing ED groups (27 of anorexia nervosa, 9 of bulimia nervosa) with controls to determine the grand mean effect on EF. Analyses included effects for individual EF measures, as well as an age-based subgroup analysis. RESULTS: There was a medium effect of ED diagnosis on executive functioning, with bulimia nervosa demonstrating a larger effect (Hedges's g=-0.70) than anorexia nervosa (g=-0.41). Within anorexia nervosa studies, subgroup analyses were conducted for age and diagnostic subtype. The effect of anorexia nervosa on EF was largest in adults; however, subgroup differences for age were not significant. CONCLUSIONS: Anorexia and bulimia nervosa are associated with EF deficits, which are particularly notable for individuals with bulimia nervosa. The present analysis includes recommendations for future studies regarding study design and EF measurement.

Effectiveness of a social robot, "Paro," in a VA long-term care setting.

Interest in animal assisted interventions (AAI) has grown over the years, but acceptance of AAI by the clinical and research community has been hampered by safety, hygiene, and logistical concerns. Advances in the field of social robotics have provided a promising route to deliver AAI while avoiding these aforementioned obstacles. Although there has been promising initial research on social robotics in older adults, to date there has been no such research conducted with a veteran population. The present pilot study followed 23 veteran residents of a Veterans Affairs (VA) geropsychiatric long-term care facility over the span of approximately a year and a half. It was found that use of Paro, a social robot, resulted in increased observed positive affective and behavioral indicators, with concomitant decreases observed in negative affective and behavioral indicators. The authors concluded that Paro is likely an effective nonpharmacological approach for managing dementia-related mood and behavior problems with veterans in VA long term care facilities. They additionally observed that Paro is best presented to residents who are relatively calm and approachable, as opposed to actively exhibiting behavior or mood problems. Future research directions are discussed in light of both the positive results noted and the inherent limitations of our pilot study. (PsycINFO Database Record