No effect of moderate alcohol intake on the detection of concealed identity information in the laboratory

Prevalence and Misreporting of Illicit Drug Use among Electronic Dance Music Festivals Attendees: A Comparative Study between Sweden and Belgium

Illicit drug use is common among attendees of electronic dance music (EDM) festivals, but is often significantly underreported by participants. The current study aimed to compare the prevalence and over- and under-reporting of illicit drug use among attendees at EDM festivals in two European countries with distinct drug laws and cultures. Self-reported data regarding recent drug use were collected through interviews. Participants' blood alcohol concentrations were measured using a breathalyzer. Recent illicit drug use was assessed through sampling microparticles in the breath and consequent off-site analysis through liquid chromatography and tandem mass spectroscopy. Illicit drug use was higher in Belgium than in Sweden as indicated by self-reports (56.8 vs. 4.3%) and drug testing (37.2 vs. 12.5%). Underreporting was higher in Sweden than in Belgium; in Sweden, only 2.6% reported taking an illicit drug other than cannabis, whereas 11.6% tested positive, while the corresponding figures in Belgium were 36.5% and 36.9%. In both countries, results from self-reporting and drug testing for specific drugs matched poorly at the individual level, indicating unwitting consumption of substances. This study indicates that the drug use prevalence and the likelihood of disclosure may differ between countries or cultures, which should be considered when choosing methods to investigate drug use prevalence.

Effects of alcohol and task difficulty on visual tracking and inattentional blindness

RATIONALE

Inattentional blindness (IB) describes the failure to notice salient but unexpected stimuli in one's focal visual field. It typically occurs while performing a demanding task (e.g. tracking and counting basketball passes), which consumes attentional resources. Alcohol intoxication is also known to reduce attentional resources, thereby potentially increasing IB and disrupting task performance.

OBJECTIVES

To test the extent to which acute alcohol and task difficulty disrupt counting performance and increase the rate of IB across two experimental tasks.

METHODS

To test the effects of alcohol consumption and task difficulty on IB, we used the Simons and Chabris (Percept 28:1059-1074, 1999) and Simons (2010) "gorilla in our midst" basketball clip in experiment 1 and abstract but analogous stimuli presented in a computerised alternative to that task in experiment 2.

RESULTS

IB was associated with increased (counting) task difficulty but not alcohol consumption. However, counting accuracy was impaired by both alcohol and increased task difficulty, with the largest detriment being for alcohol participants who noticed the salient but unexpected stimulus.

CONCLUSION

The absence of alcohol effects on IB in both experiments was unexpected and warrants further investigation in a field vs lab study comparison and in combination with baseline cognitive measures to test for alcohol expectancy and task compensation effects.