Ies [FIGS]; Maxwell, 1992). AVP biological activity Testing Session Procedures Prior to testing, participants abstained for >3 hr from caffeine and/or smoking/nicotine, too as from alcohol/drugs (other than contraceptives and medication necessary for a stabilized physical situation) starting at midnight. Upon arrival towards the laboratory, subjective mood evaluations have been carried out. Concurrently, electrodes were applied, after which the experiment commenced. This study was approved by the Royal Ottawa Health Care Group as well as the University of Ottawa Social Sciences and Humanities Research Ethics Boards and informed consent was obtained from all participants. Participants wereJ Impact Disord. Author manuscript; obtainable in PMC 2013 February 1.Jaworska et al.Pagecompensated 30.00 CDN/session (individuals participated in a number of sessions as a part of a larger study).NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptSubjective Mood Questionnaires Mood was assessed using the Profile of Mood States (POMS; McNair et al., 1992) on which participants rated their subjective state making use of a Likert scale on 65 mood adjectives, from which values had been aggregated to form seven mood dimensions (tension-anxiety, depressiondejection, anger-hostility, vigor-activity, fatigue-inertia, confusion-bewilderment and total mood disturbance). Emotional Faces Recognition Process The faces recognition activity was adapted from Krolak-Salmon et al. (2001). Thirty-six photographic faces displaying certainly one of four expressions (sadness [sad], joy, surprise [sur], neutral) were presented individually on a screen in front with the seated participant ( 1 m) within a dim, electrically-shielded and sound-attenuated space. Each emotion was expressed at three intensities (20 , 50 , 100 ) by one actor. Two males and two females displayed one emotion at all intensities (i.e., 16 actors). Expressions at 20 intensity have been considered “neutral” as they are not reliably distinguished (Orgeta Phillips, 2008) and 0 expressions are far more likely to be confused with unfavorable than with other facial expressions (Palermo Coltheart, 2004). Photographs were digitized and converted to grey-scale images, matched for luminance and contrast, with the neck and hair cropped out (Figure 1). Each and every expression (neutral, sad50, sad100, joy50, joy100, sur50, sur100) was pseudorandomly presented 80 times (no identical faces presented back-to-back) for 400 ms (ISI: 1500 ms; Presentation Computer software, Neurobehavioral Systems, Albany, CA, USA). Participants pressed a button to shocked faces (sur50, sur100) to ensure that they paid attention to expressions. Hits ( right responses to sur50 sur100), false alarms (FA; responses to non-surprised faces) and reaction times (RT) were recorded. Facial Expression Rating Questionnaire Right after the activity, participants rated 10 faces (one male and one particular female expressing every single of joy50, joy100, sad50, sad100 and neutral) presented in the course of the activity. Faces have been rated making use of a Likert scale from 0 (not at all) to ten (really a great deal) on two valence questions: how 1) “sad” and 2) “happy” does the face look. Participants rated the faces based on their gut reaction, taking 2? min to rate all faces. Two questionnaire versions, containing distinct faces but bearing precisely the same expressions, had been administered. No variations existed involving the versions, hence, ratings have been averaged across the questionnaires. Electrophysiological Recordings PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/21228935/ Data Reduction EEG activity was recorded (500 Hz) utilizing a cap embedded.
