Sivan Raz
Tel-Hai Academic College
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Publication
Featured researches published by Sivan Raz.
Journal of Behavior Therapy and Experimental Psychiatry | 2014
Rany Abend; Orrie Dan; Keren Maoz; Sivan Raz; Yair Bar-Haim
BACKGROUND AND OBJECTIVES Assessment of state anxiety is frequently required in clinical and research settings, but its measurement using standard multi-item inventories entails practical challenges. Such inventories are increasingly complemented by paper-and-pencil, single-item visual analog scales measuring state anxiety (VAS-A), which allow rapid assessment of current anxiety states. Computerized versions of VAS-A offer additional advantages, including facilitated and accurate data collection and analysis, and applicability to computer-based protocols. Here, we establish the psychometric properties of a computerized VAS-A. METHODS Experiment 1 assessed the reliability, convergent validity, and discriminant validity of the computerized VAS-A in a non-selected sample. Experiment 2 assessed its sensitivity to increase in state anxiety following social stress induction, in participants with high levels of social anxiety. RESULTS Experiment 1 demonstrated the computerized VAS-As test-retest reliability (r = .44, p < .001); convergent validity with the State-Trait Anxiety Inventorys state subscale (STAI-State; r = .60, p < .001); and discriminant validity as indicated by significantly lower correlations between VAS-A and different psychological measures relative to the correlation between VAS-A and STAI-State. Experiment 2 demonstrated the VAS-As sensitivity to changes in state anxiety via a significant pre- to during-stressor rise in VAS-A scores (F(1,48) = 25.13, p < .001). LIMITATIONS Set-order administration of measures, absence of clinically-anxious population, and gender-unbalanced samples. CONCLUSIONS The adequate psychometric characteristics, combined with simple and rapid administration, make the computerized VAS-A a valuable self-rating tool for state anxiety. It may prove particularly useful for clinical and research settings where multi-item inventories are less applicable, including computer-based treatment and assessment protocols. The VAS-A is freely available: http://people.socsci.tau.ac.il/mu/anxietytrauma/visual-analog-scale/.
Assessment | 2014
Sivan Raz; Yair Bar-Haim; Avi Sadeh; Orrie Dan
Continuous Performance Tests (CPTs) are used in research and clinical contexts to measure sustained attention and response inhibition. Reliability and validity of a new Online Continuous Performance Test (OCPT) was assessed. The OCPT is designed for delivery over the Internet, thereby opening new opportunities for research and clinical application in naturalistic settings. In Study 1, participants completed the OCPT twice over a 1-week period. One test was taken at home and one in the laboratory. Construct validity was assessed against a gold standard CPT measure. Results indicate acceptable reliability between the home- and laboratory-administered tests. Modest to high correlations were observed between the OCPT scales and the corresponding scales of the gold standard CPT. Study 2 examined whether the OCPT may discriminate participants with attention deficit hyperactivity disorder from healthy controls. Results revealed significantly higher rates of omission and commission errors and greater response time variability in participants with attention deficit hyperactivity disorder relative to healthy controls. These results support the reliability and validity of the OCPT and suggest that it may serve as an effective tool for the assessment of attention function in naturalistic settings.
Journal of Attention Disorders | 2015
Orrie Dan; Sivan Raz
Objective: The comorbidity of adult ADHD with test anxiety (TA) has not been previously reported. This comorbidity can potentially affect clinical and academic interventions among individuals with ADHD. The present study investigated the relationships among ADHD, self-esteem, and three subscales of TA among young adults: Cognitive Obstruction, Social Derogation, and Tenseness. Method: A total of 25 female participants diagnosed with ADHD and 30 female controls without ADHD of comparable age and education completed an Online Continuous Performance Test, an ADHD questionnaire, a self-esteem inventory, and a TA questionnaire. Results: Participants with ADHD exhibited significantly higher levels of TA on all three subscales and lower levels of self-esteem compared with controls. Self-esteem served as a partial mediator between ADHD and cognitive obstruction TA and as a full mediator between ADHD and social derogation TA, but had no mediation effect in the relationships between ADHD and tenseness TA. Conclusion: The findings of this study suggest that TA, well known to affect success on tests, is correlated with ADHD. Therefore, interventions for ADHD should include components aimed at reducing TA.
Biological Psychology | 2012
Orrie Dan; Sivan Raz
Attachment-related electrophysiological differences in emotional processing biases were examined using Event-Related Potentials (ERPs). We identified ERP correlates of emotional processing by comparing ERPs elicited in trials with angry and neutral faces. These emotional expression effects were then compared across groups with secure, anxious and avoidant attachment orientations. Results revealed significant interactions between attachment orientation and facial expression in mean amplitudes of the early C1 (50-80 ms post-stimulus) and P1 (80-120 ms post-stimulus) ERP components. Significant differences in C1 and P1 mean amplitudes were found at occipital and posterior-parietal channels in response to angry compared with neutral faces only within the avoidant attachment group. No such differences were found within the secure or anxious attachment groups. The present study underscores the usefulness of the ERP methodology, as a sensitive measure for the study of emotional processing biases in the research field of attachment.
Brain and Cognition | 2014
Sivan Raz; Orrie Dan; Leehu Zysberg
The present study was aimed at identifying potential behavioral and neural correlates of Emotional Intelligence (EI) by using scalp-recorded Event-Related Potentials (ERPs). EI levels were defined according to both self-report questionnaire and a performance-based ability test. We identified ERP correlates of emotional processing by using a visual-emotional oddball paradigm, in which subjects were confronted with one frequent standard stimulus (a neutral face) and two deviant stimuli (a happy and an angry face). The effects of these faces were then compared across groups with low and high EI levels. The ERP results indicate that participants with high EI exhibited significantly greater mean amplitudes of the P1, P2, N2, and P3 ERP components in response to emotional and neutral faces, at frontal, posterior-parietal and occipital scalp locations. P1, P2 and N2 are considered indexes of attention-related processes and have been associated with early attention to emotional stimuli. The later P3 component has been thought to reflect more elaborative, top-down, emotional information processing including emotional evaluation and memory encoding and formation. These results may suggest greater recruitment of resources to process all emotional and non-emotional faces at early and late processing stages among individuals with higher EI. The present study underscores the usefulness of ERP methodology as a sensitive measure for the study of emotional stimuli processing in the research field of EI.
Clinical Neurophysiology | 2015
Sivan Raz; Orrie Dan
OBJECTIVE This study investigated behavioral and neural correlates of emotional processing in adults with ADHD using scalp-recorded event-related potentials (ERPs). METHODS We used a visual-emotional oddball paradigm, in which subjects were confronted with neutral and emotional faces (happy and angry). Responses to target and non-target stimuli were compared across groups of 17 adults with ADHD and 20 control subjects. RESULTS Participants with ADHD had slower RTs than controls in response to happy but not to angry faces. ADHD participants, but not controls, responded faster to angry than to happy faces. ERP results indicated that group significantly interacted with the type of facial expression. P1 was significantly increased for the ADHD group compared with controls, but only to emotional (and not to neutral) faces. In the ADHD group, but not in controls, P1 was greater in response to emotional compared with neutral faces. N170 was more pronounced to angry than to happy faces in the ADHD group, while in the control group N170 was more pronounced to happy than to angry faces. Participants with ADHD showed a pronounced reduction in P3 to both emotional and neutral faces. CONCLUSIONS The current results provide indication of altered behavioral responses as well as altered P1, N170 and P3 to emotional faces in adults with ADHD compared with healthy controls. SIGNIFICANCE Behavioral and brain function measures of emotion processing may provide valuable additional tools for clinical assessment of ADHD in adulthood.
Assessment | 2014
Orit Bart; Sivan Raz; Orrie Dan
Objective. The study assesses the reliability and validity of a new Online Continuous Performance Test (OCPT) for measuring sustained attention, response inhibition, and response time consistency among children. Method. The study sample comprised 73 children (6-13 years), 47 children with attention deficit hyperactivity disorder and 24 in the control group. The Diagnostic Interview Schedule for Children was administered to participants’ parents to confirm group allocation. Children completed the OCPT in a laboratory setting, and a week later completed the OCPT at home. Results. Split-half correlation coefficients reflected high levels of reliability in the laboratory and at home. Significant correlations were found between the laboratory- and home-based OCPT scores. Significant differences in OCPT performance were found between children with and without attention deficit hyperactivity disorder on the OCPT in the two settings. Conclusions. These results support the reliability and validity of the OCPT and suggest that it may serve as an effective tool for the assessment of children’s attention function in naturalistic settings.
Behavioural Brain Research | 2014
Sivan Raz
The present study was aimed at identifying potential behavioral and neural correlates of cognitive and emotional processing during pregnancy using scalp-recorded Event-Related Potentials (ERPs). We used a 4-stimulus visual oddball task, combining emotional and non-emotional stimuli. Responses to target and non-target stimuli were compared across groups of 17 pregnant women on their third trimester and 19 non-pregnant women. Participants also completed a non-emotional test of sustained attention and response inhibition; the Online Continuous Performance Test (OCPT). Pregnant women had poorer performance than controls on most indices of the OCPT and the oddball task. ERP results indicated that pregnancy significantly interacted with the type of target stimuli. Results of the P3 component have demonstrated a comparative reduction in P3 amplitude in pregnant women in response to the target emotional faces but not in response to the target shapes. Moreover, among pregnant women, P3 amplitude was greater for the target shapes than for the target faces, while in non-pregnant women P3 amplitude was greater for the target faces than for the target shapes. Results of the N170 component showed that N170 to faces, but not to shapes, was more pronounced in pregnant women compared with non-pregnant women. The current results provide indication of modulation of cognitive-affective function during pregnancy. ERP alterations may suggest changes in the recruitment of neural resources to process emotional stimuli and alterations in attention allocation and evaluation of emotional stimuli among pregnant women.
Brain Research | 2013
Sivan Raz; Orrie Dan; Hen Arad; Leehu Zysberg
The present study was aimed at identifying potential behavioral and neural correlates of emotional intelligence (EI) by using scalp-recorded Event-Related Potentials (ERPs). EI levels were defined according to both self-report questionnaire and a performance-based test. We identified ERP correlates of emotional processing by comparing ERPs elicited in trials using pleasant, neutral and unpleasant pictures. The effects of these emotion-inducing pictures were then compared across groups with low and high EI levels. Behavioral results revealed a significant valence×EI group interaction effect since valence ratings were lower for unpleasant pictures and higher for pleasant pictures in the high EI group compared with the low EI group. The groups did not differ with respect to neutral picture ratings. The ERP results indicate that participants with high EI exhibited significantly greater mean amplitudes of the P2 (200-300ms post-stimulus) and P3 (310-450ms post-stimulus) ERP components in response to emotional and neutral pictures, at posterior-parietal as well as at frontal scalp locations. This may suggest greater recruitment of resources to process all emotional and non-emotional stimuli at early and late processing stages among individuals with higher EI. The present study also underscores the usefulness of ERP methodology as a sensitive measure for the study of emotional stimuli processing in the research field of EI.
Psychoneuroendocrinology | 2015
Sivan Raz; Dmitry Leykin
Individuals with ADHD suffer from increased vulnerability to environmental and mental stressors and may be at increased risk for chronic stress in everyday life. The Hypothalamic-Pituitary-Adrenal (HPA) axis is a critical physiological system that mediates responses to stress. The present study seeks to examine test performance, test anxiety, self-reported psychological stress and cortisol reactivity to mental-cognitive stress in adults with ADHD when compared with healthy controls. Stress was induced by an arithmetic ability test. Psychological stress was assessed repeatedly throughout the experimental session. Salivary cortisol, an indicator of the HPA axis function, was evaluated immediately upon arrival, as well as 1 min and 20 min post-test completion. Results revealed higher levels of test anxiety and poorer performance on the test in the ADHD group. The ADHD and control groups showed no difference in base-line levels of subjective stress and in subjective stress levels 20 min after the test. In contrast, individuals with ADHD reported significantly higher levels of stress at the test anticipation phase and 1 min post-test completion. Cortisol response to stress differed according to group: in the ADHD group, 20 min post-test cortisol levels were significantly higher than base-line cortisol levels. This was not evident in the control group. These results suggest greater activation of the HPA axis in response to stress in adults with ADHD when compared with healthy controls. Adults with ADHD do not differ from controls in basal levels of subjective stress and cortisol, but do have stronger psychophysiological reactions in response to stressful challenges. The present findings are among the first to demonstrate significant alterations in cortisol reactivity to stress in adults with ADHD.