Altered Plasma Levels of Glial Cell Line-Derived Neurotrophic Factor in Patients with Internet Gaming Disorder: A Case-Control, Pilot Study

Glial cell line-derived neurotrophic factor (GDNF) has been reported to be involved in negatively regulating the effects of addictive disorders. The objective of this study was to investigate alterations in the levels of GDNF in patients with Internet gaming disorder (IGD) and to assess the relationship between GDNF levels and the severity of IGD indices. Nineteen male patients with IGD and 19 sexmatched control subjects were evaluated for alteration of plasma GDNF levels and for relationship between GDNF levels and clinical characteristics of Internet gaming, including the Young's Internet Addiction Test (Y-IAT). The GDNF levels were found to be significantly low in patients with IGD (103.2±62.0 pg/mL) compared with the levels of controls (245.2±101.6 pg/mL, p<0.001). GDNF levels were negatively correlated with Y-IAT scores (Spearman's rho=-0.645, p=<0.001) and this negative correlation remained even after controlling for multiple variables (r=-0.370, p=0.048). These findings support the assumed role of GDNF in the regulation of IGD.

Effect of Stress and Serotonin-Transporter-Linked Polymorphic Region Variants on Internet Gaming Disorder in Korean Adults

OBJECTIVES: Internet gaming disorder (IGD) is known to be related to stress and the serotonin-transporter-linked polymorphic region (5-HTTLPR) that is known to be associated with stress and has been studied to affect various psychiatric illness outbreaks. We tried to examine the relationship between stress, 5-HTTLPR and IGD. METHODS: A total of 59 participants with IGD, diagnosed according to the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria and 67 normal controls (NC) were enrolled. The IGD group and the NC were compared using chisquare test and independent sample t-test, and logistic regression analysis was used to examine the relationship between stress, the 5-HTTLPR, and IGD. RESULTS: The mean scores for anxiety, impulsivity and stress were significantly higher in the IGD group than in the NC. In addition, there was a significant association between stress and IGD [odds ratio (OR) = 1.172, 95% confidence interval (CI) = 1.008–1.362]. CONCLUSIONS: This study showed that stress would affect IGD. Therefore, the evaluation and management of stress should be included in the diagnosis and treatment of IGD.

Comparing the Self-Report and Measured Smartphone Usage of College Students: A Pilot Study

OBJECTIVE: Nowadays smartphone overuse has become a social and medical concern. For the diagnosis and treatment, clinicians use the self-report information, but the report data often does not match actual usage pattern. The paper examines the similarity and variance in smartphone usage patterns between the measured data and self-reported data. METHODS: Together with the self-reported data, the real usage log data is collected from 35 college students in a metropolitan region of Northeast Asia, using Android smartphone monitoring application developed by the authors. RESULTS: The unconscious users underestimate their usage time by 40%, in spite of 15% more use in the actual usage. Messengers are most-used application regardless of their self-report, and significant preference to SNS applications was observed in addict group. The actual hourly pattern is consistent with the reported one. College students use more in the afternoon, when they have more free time and cannot use PCs. No significant difference in hourly pattern is observed between the measured and self-report. CONCLUSION: The result shows there are significant cognitive bias in actual usage patterns exists in self report of smartphone addictions. Clinicians are recommended to utilize measurement tools in diagnosis and treatment of smartphone overusing subjects.

Comprehensive Evaluation of Internet Gaming Disorder : Clinical and Neurobiological Assessments / 신경정신의학

A growing body of evidence supports that Internet gaming disorder (IGD) is considered as ‘behavioral addiction’ with neurobiological alterations. We have reviewed previous research into the clinical and neurobiological features of IGD, and suggest a flowchart for the comprehensive evaluation of IGD. Several self-rating screening tests based on Diagnostic and Statistical Manual of Mental Disorder, 5th edition (DSM-5) IGD criteria were developed. IGD is often comorbid with depressive disorder, social anxiety disorder, attention deficit/hyperactivity disorder (ADHD), and smartphone addiction. Individuals with IGD are prone to act impulsively and make risky decisions, especially in response to game-related cues. Functional neuroimaging results have shown altered functional activities in prefrontal cortex, cingulate cortex, superior temporal gyrus and nucleus accumbens (NAc). Structural neuroimaging demonstrated gray matter volume changes in prefrontal cortex and NAc, while showing white matter integrity disruption in thalamus and posterior cingulate cortex. There are few evidences on the attribution of specific genes to IGD. To evaluate IGD comprehensively, self-rating scales based on DSM-5 are useful, but a diagnostic interview by a clinician is more helpful to assess functional impairments of IGD. Presence of psychiatric comorbidities such as depressive disorder, social anxiety disorder, ADHD, and smartphone addiction should be evaluated. Neurocognitive tests that assess impulsivity, decision-making under risk, and cue-reactivity are helpful when planning individualized IGD treatment.

Characteristics and Psychiatric Symptoms of Internet Gaming Disorder among Adults Using Self-Reported DSM-5 Criteria

OBJECTIVE: The Section III of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) proposed nine diagnostic criteria and five cut-point criteria for Internet Gaming Disorder (IGD). We aimed to examine the efficacy of such criteria. METHODS: Adults (n=3041, men: 1824, women: 1217) who engaged in internet gaming within last 6 months completed a self-report online survey using the suggested wordings of the criteria in DSM-5. Major characteristics, gaming behavior, and psychiatric symptoms of IGD were analyzed using ANOVA, chi-square, and correlation analyses. RESULTS: The sociodemographic variables were not statistically significant between the healthy controls and the risk group. Among the participants, 419 (13.8%) were identified and labeled as the IGD risk group. The IGD risk group scored significantly higher on all motivation subscales (p<0.001). The IGD risk group showed significantly higher scores than healthy controls in all nine psychiatric symptom dimensions, i.e., somatization, obsession-compulsion, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, and psychoticism (p<0.001). CONCLUSION: The IGD risk group showed differential psychopathological manifestations according to DSM-5 IGD diagnostic criteria. Further studies are needed to evaluate the reliability and validity of the specific criteria, especially for developing screening instruments.

Genetic Association of CHRNB3 and CHRNA6 Gene Polymorphisms with Nicotine Dependence Syndrome Scale in Korean Population

OBJECTIVE: Cholinergic nicotinic receptor (CHRN) gene family has been known to mediate the highly additive effects of nicotine in the body, and implicated nicotine dependence (ND) and related phenotypes. Previous studies have found that CHRNA6-CHRNB3 cluster polymorphisms were significantly associated with the risk of ND and various tobacco behaviors. The aim of study was to evaluate the genetic association of CHRNB3 and CHRNA6 polymorphisms with the risk of ND based on the Fagerstrom Test for Nicotine Dependence (FTND) score and five subscales of nicotine dependence syndrome scale (NDSS) in Korean population. METHODS: Six SNPs in CHRNA6-CHRNB3 cluster were analyzed in 576 Korean subjects. Association analysis using logistic models and regression analysis with NDSS were performed. RESULTS: There was no association in the case-control analysis, whereas all six SNPs were significantly associated with drive factor among NDSS in subgroup based on the FTND score. CHRNB3 rs4954 and CHRNA6 rs16891604 showed significant associations with NDSSF1 (drive) in dominant models among moderate to severe ND among smokers after correction (p(corr)=0.02 and 0.001, respectively), whereas other four SNPs showed significant associations among mild ND after correction (p(corr)=0.03-0.02 in dominant model). CONCLUSION: This study showed that the genetic influence of CHRNB3-CHRNA6 cluster polymorphisms are found in a ND endophenotype (drive) using NDSS subscales, rather than the risk of ND in Korean population. Our findings might be the first report for the association of CHRNB3-CHRNA6 cluster with ND-related phenotypes in Korean and might offer an approach to elucidating the molecular mechanisms of ND and ND-related phenotypes.

Korean Addiction Treatment Guidelines (III) : Psychosocial Treatment of Alcohol Use Disorder / 신경정신의학

OBJECTIVES: The aim of this study is to develop guidelines for psychosocial treatment of alcohol use disorder. METHODS: According to the ADAPTE manual, the Korean alcohol use disorder treatment guidelines were developed by the guideline development committee. Recommendations from foreign guidelines were evaluated regarding the applicability and acceptability to domestic circumstances. In addition, a survey from experts was conducted, along with a review of Korean literature. By these means, recommendations of psychosocial treatment for alcohol use disorder were established. RESULTS: The main findings of the survey were as follows : 1) Although Group therapy was not recommended by foreign clinical guidelines, it was considered as a first-line treatment by Korean experts. 2) Among many psychosocial treatment programs, cognitive behavior therapy (CBT), coping skills training, 12-step facilitation, and Group therapy were commonly used programs in Korea. Finally, the following treatment methods were selected for recommendations : Group therapy, motivational enhancement treatment, CBT, behavioral self-management, alcoholic anonymous, 12-step facilitation, psychodynamic psychotherapy, psychoeducational intervention, continuous case management, and community residential rehabilitation program. CONCLUSION: Just as in treatment of chronic diseases such as hypertension, continuity is important for management of alcohol use disorder. Therefore, not only pharmacological treatment but also psychosocial treatment should be provided comprehensively after treatment of acute withdrawal symptoms.

The Difference in Comorbidities and Behavioral Aspects between Internet Abuse and Internet Dependence in Korean Male Adolescents

OBJECTIVE: This study examined the differences in psychiatric comorbidities and behavioral aspects in accordance with the severity of Internet addiction in male adolescents. METHODS: One hundred and twenty-five adolescents from four middle and high schools in Seoul were enrolled in this study. The subjects were divided into non-addict, abuse, and dependence groups according to a diagnostic interview by psychiatrists. The psychiatric comorbidities and behavioral aspects of subjects were evaluated through psychiatric clinical interviews based on the Diagnostic and Statistical Manual of Mental Disorders (4th edition), the Children's Depression Inventory, the State-Trait Anxiety Inventory, the Internet Addiction Test, and a self-reported questionnaire about behavioral aspects. RESULTS: The psychiatric comorbidity distributions were significantly different in the abuse and dependence groups, particularly in terms of attention-deficit hyperactivity disorder and mood disorder items. The Children's Depression Inventory, the State-Trait Anxiety Inventory, and the Internet Addiction Test scores were also significantly different among the three groups. There were significant differences in 10 of the 20 items of the Internet Addiction Test between the non-addict, abuse, and dependence groups. There were significant differences in seven items between the non-addict and abuse groups, but no differences between subjects in the abuse and dependence groups. Significant differences were observed in three items between the abuse and dependence groups, but there were no significant differences between the non-addict and abuse groups. In terms of behavioral aspects, scores for abusive, sexual, and decreased social interest behaviors were highest in the dependence group, and lowest in the non-addict group. However, the behavioral aspects of decreased interpersonal relationships did not show this difference between groups. CONCLUSION: This study suggests that there are differences in psychiatric comorbidities and behavioral aspects between adolescent males with characteristics of Internet abuse and Internet dependence.

Relationship between Internet Game Addiction and Psychiatric Symptoms in a Child and Adolescent Psychiatric Clinic

OBJECTIVES: The aim of this study was to examine the relationship between internet game addiction and psychiatric symptoms. METHODS: A total of 447 adolescents who were recruited from a child and adolescent psychiatric clinic of university hospital completed a self-report questionnaire consisting of Korean Internet Addiction Self-scale (K-scale), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Korean-Attention-Deficit Hyperactivity Disorder Rating Scale (K-ARS), and Adolescent Happiness Index (AHI). They were classified into three internet user groups, non-addicted group (below or equal to 94), potential risk group (95 to 107) and high risk group (above or equal to 108) according to K-scale total score. RESULTS: Significant mean differences in BDI, BAI, K-ARS, and AHI scores were observed among the three groups. The BDI, BAI and K-ARS scores showed positive correlation with K-score. The AHI score showed negative correlation with K-score. CONCLUSION: Findings of this study suggest that depression, anxiety, inattention, hyperactivity/impulsivity, and happiness are associated with internet game addiction.

Korean Addiction Treatment Guidelines Series (I) : Development of Korean Guidelines for the Treatment of Alcohol Use Disorder / 신경정신의학

OBJECTIVES: The aim of this study is to develop Treatment Guidelines for Alcohol Use Disorder-the Korean Addiction Treatment Guidelines-using the Adaptation method. METHODS AND PROCEDURES: As the Adaptation method of Guidelines, the ADAPTE Manual, which is developed by ADAPTE collaboration is applied. In Part 1 : preparatory work prior to the beginning of Adaptation is performed. In Part 2 : the core phase of the Adaptation in which we searched the guidelines and performed a systematic review of the literature. The two guidelines (of the AU and the UK) are selected by gone through the methodological quality and currency evaluation for guidelines. And, in order to choose the proper recommendations, the contents were evaluated with regard to the applicability and acceptability of guidelines to the domestic. Finally, in Part 3 : the adapted guideline is reviewed externally, with review and plan update. Therefore, in this way, the Korean Guidelines for Treatment of Alcohol Use Disorder, comprised of 55 recommendations, was developed. CONCLUSION: In this study, Korean Guidelines for Treatment of Alcohol Use Disorder were developed by application of the Adaptation method of ADAPTE. These are the first evidence-based Korean Guidelines for Treatment of Alcohol Use Disorder, which were modified and accepted in accordance with Korean circumstances within the range not damaging the validity of the treatment worth, and it is expected to contribute to improvement in quality and efficiency enhancement of Korean treatment of Alcohol Use Disorder.

Korean Addiction Treatment Guidelines Series (II): Pharmacological Treatment of Alcohol Withdrawal / 신경정신의학

OBJECTIVES: In development of Korean addiction treatment guidelines, the aim of this study was to investigate the experts' consensus regarding current pharmacological practice in treatment of alcohol withdrawal. METHODS: Using recommendations from foreign clinical guidelines, which were either lacking in evidence or could not be directly applied to Korea, the executive committee developed a questionnaire consisting of 17 questions. Using a nine-point scale, members of the Korean Addiction Psychiatry, who were experts (n=150) with sufficient experience in treatment of alcohol use disorder, were asked to evaluate the appropriateness of each item on the questionnaire. We classified the experts' opinion according to three categories, based on the lowest scores of 6.5 or greater as a first-line/preferred treatment, 3.5-6.5 as a second-line/reasonable treatment, and lower than 3.5 as a third-line/inappropriate treatment. The consensus was determined by chi-square test (p<0.05). Response rate was 70.4% (81/115). RESULTS: The results of the survey from the experts were as follows: 1) Symptom triggered therapy (STT) was the most appropriate strategy in treatment of alcohol withdrawal (95% CI 7.41-8.04). 2) Prophylactic benzodiazepine was recommended for management of expecting alcohol withdrawal in out-patient-department patients. 3) Among benzodiazepines, lorazepam was the most preferred. 4) For patients with severe withdrawal, lorazepam 7.4 mg/day (95% CI 6.48-8.25, maximum dose=20 mg) was recommended. 5) Risperidone, quetiapine, and haloperidol were the first-line drugs for patients with alcohol withdrawal and combined psychotic symptoms. 6) 127.5 mg (95% CI 111-145) for 2.8 months of prophylactic thiamine and 213.5 mg (95% CI 190-240) for 6.2 months of thiamine for Wernicke-Korsakoff's syndrome were recommended. CONCLUSION: We hope that these Korean addiction treatment guidelines, added by the Korean experts' consensus, will be helpful in promoting the efficacy of treatment for alcohol withdrawal.

Rash in Psychiatric and Nonpsychiatric Adolescent Patients Receiving Lamotrigine in Korea: A Retrospective Cohort Study

OBJECTIVE: Lamotrigine is a widely used medication for psychiatric disorders and epilepsy, but the adverse effects of this drug in adolescent Korean patients have not yet been investigated. In the present study, we sought to compare the incidence and impact of lamotrigine-induced skin rashes and different pattern of adverse events in psychiatric and nonpsychiatric adolescent patients. METHODS: Using a retrospective cohort design, all of the charts were reviewed for adolescents (13 to 20 years old), treated with lamotrigine during the previous 2 years in the Child and Adolescent Psychiatric Clinic and Pediatric Neurologic Clinic of the Ulsan University Hospital in South Korea. RESULTS: Of the 102 subjects, 23 patients developed a skin rash. All of these rashes were observed within 7 weeks of the initiation of the lamotrigine therapy. Only one subject developed a serious rash, which was diagnosed as Stevens-Johnson syndrome. Although the psychiatric subjects were administered statistically lower doses of lamotrigine during weeks 1 through 5 and at week 12, the likelihood of developing a rash was not significantly different between the psychiatric and nonpsychiatric patients. CONCLUSION: Careful dose escalation and close observation of side effects for the first 7 weeks of treatment is important. The present study reveals the tolerability of lamotrigine in an adolescent population, although a double-blind, controlled trial is needed to confirm these findings.

The Development of the 'Mental Fitness' Scale / 신경정신의학

OBJECTIVES: The purpose of this study was to develop and validate the 'Mental Fitness'Scale, which was designed to measure the characteristics of being mentally fit or positive mental health. METHODS: Interviews using open-ended questions were conducted on 105 healthy adults between 20 and 65 years of age to obtain the 25 candidate items of the 'Mental Fitness' Scale. To evaluate the validity of the new scale, these items and the Beck Depression Inventory (BDI), the Positive and Negative Affect Scale (PANAS), and the Epworth Sleepiness Scale(ESS) were administered to 212 healthy adults. To assess test-retest reliability, the preliminary 'Mental Fitness' Scale items were administered two weeks later to 47 healthy subjects selected by random sampling. A comparison was made between the 212 healthy subjects and 42 psychiatric patients with depressive or anxiety disorders. RESULTS: Factor analysis yielded four subscales (mental energy, empathic communication, flexibility, and self-assurance). Five items were excluded due to their low factor loadings. The test-retest reliability coefficients were significantly high, ranging between 0.57-0.76. Internal consistency was computed, and Cronbach's alpha for four subscales ranged between 0.66-0.88, and was 0.90 for the total score. Concurrent validity was assessed by correlating the four subscales and the total score with total scores on the BDI, PANAS, and ESS. The correlations were all at significant levels. CONCLUSION: These results indicate that the 'Mental Fitness' Scale is a reliable and valid instrument for assessing positive mental health.

Changes of Functional MRI Findings in a Patient Whose Pathological Gambling Improved with Fluvoxamine

Legalized gambling is a growing industry, and is probably a factor in the presently increasing prevalence of pathological gambling. We present a case of a 36-year-old pathological gambler who was treated with fluvoxamine, a selective serotonin reuptake inhibitor, and who was assessed by functional MRI before and after drug administration. During activation periods, the pathological gambler was shown cards as stimuli, and fMRI results in several brain regions showed differential effects before and after medication and a maintenance period. This case demonstrates that the treatment response to fluvoxamine in a pathological gambler was observed not only by subjective self-report, but also by objective fMRI results. Therefore, fMRI may be a useful tool in the diagnosis and prediction of treatment response in patients afflicted with pathological gambling.

Stress, Coping Style and Depression in Pathological Gamblers / 신경정신의학

OBJECTIVES: The present study aimed to improve understanding and treatment of pathological gambling by comparing levels of stress, coping styles, depression, 'Gambling attitudes and Beliefs' in pathological gamblers to groups of non-pathological gambling controls. METHODS: Pathological gambling was measured by the South Oaks Gambling Scale, depression by the Beck Depression Inventory, stress by Daily Hassles Scales, attitude and belief about gambling by the Gambling Attitude and Belief Scale and coping styles by Problem-focused Styles of Coping Inventory. RESULTS: Pathological gamblers reported significantly higher level of stress, depression, the Gambling Attitude and Belief, craving and more maladaptive styles of coping (reactive and suppressive) than control groups. Pathological gambler's use of maladaptive coping was disappeared when depression was controlled. CONCLUSION: The results of this study suggest that pathological gambler's maladaptive styles of coping might close related to depression, and treatment which is designed to improve depression and their ability to engage in reflective coping when stressors arise will be helpful. Further longitudinal studies may clarify the ways in which pathological gambler's depression and coping styles interact over time.

The Effect of ADH1B and NQO2 Polymorphisms on the Age of Onset of Alcohol Dependence and Alcohol Withdrawal Symptoms / 신경정신의학

OBJECTIVES: We hypothesized that polymorphisms of ADH1B and NQO2 could have an effect on the onset of alcohol dependence and withdrawal symptoms. METHODS: PCR (polymerase chain reaction) and RFLP (restriction fragment length polymorphism) were used to analyze genetic polymorphisms of ADH1B and NQO2 in 194 male patients with alcohol dependence (AD) and 152 healthy comparisons. The AD were classified into the early and late onset groups with the onset age of 25. Alcohol withdrawal symptoms were measured by Clinical Institute Withdrawal Assessment for Alcohol Scale (CIWA-Ar). RESULTS: 1) Alcohol dehydrogenase 1B gene : There was no difference in genotype distribution between the patients group and the control group. However, the frequency of ADH1B*2 allele in late-onset alcohol dependence was higher compared to the early-onset group. 2) NRH-quinone oxidoreductase 2 (NQO2) : The patients group had higher frequency of D allele than the healthy comparisons. In patients group, the frequency of the D allele in the late-onset group was higher than the early-onset group. 3) CIWA-Ar scale : There was no difference in the CIWA-Ar scale between the genetic polymorphisms of ADH1B. However, the patients with D allele of NQO2 showed significantly higher scores in the CIWA-Ar scale than those with I/I allele. CONCLUSION: With current results, we suggested that ADH1B*2 and D allele of NQO2 may have a possible association with alcohol withdrawal symptoms and that they may play a protective role in the onset of alcohol dependence.

The Relationship between Quality of Life and Psycho-Socio-Spiritual Characteristics in Male Patients with Alcohol Dependence / 신경정신의학

OBJECTIVES: This study was designed to evaluate the relationship between quality of life (QOL) and psycho-socio-spiritual characteristics in male patients with alcohol dependence. METHODS: The sample consisted of 109 men with alcohol dependence defined by DSM-IV criteria. We assessed QOL by the WHO QOL assessment instrument-BREF (WHOQOL) and SmithKline Beecham QOL (SBQOL). Sociodemographic and alcohol related data were collected, and 7 questionnaires were administered: MAST, BDI, STAI, Drinker Inventory of Consequences (DrInC), Scale of Social Support (SSS), Religious Beliefs and Behaviors (RBB) and Spiritual Well-being Scale (SWBS). The correlations between each QOL score and other variables were examined, and stepwise multiple regression analysis was performed. RESULTS: The WHOQOL score positively correlated with education level, SSS (support) and RBB and negatively correlated with MAST, DrInC, BDI, STAI (trait) and SSS (conflict) scores. In stepwise regression analysis, the scores on the STAI and BDI contributed to the score on the WHOQOL. The SBQOL score correlated with the income level, and negatively correlated with BDI and STAI score. STAI score was a weak predictor of SBQOL score. CONCLUSION: The significant predictors of QOL in patients with alcohol dependence were psychological factors such as anxiety and depression.

Acute Effect of Single Oral Administration of Nefazodone and Trazodone of Psychomotor Performance: A Duble-Blind Cross-Over Comparison in Healthy Volunteers / 대한정신약물학회지

OBJECTIVE: New antidepressant, nefazodone is classified as a serotonin -2 antagonist/reuptake inhibitor like old antidepressant, trazodone. Nefazodone, however, differs from trazodone in that it lacks anti-histaminergic properties and in that it has some norepinephrine reuptake inhibitory properties. These differences may account for the differences between the two drugs in the side effect profiles. This study was conducted to compare the acute effects of nefazodone on the psychomotor performance with those of trazodone. METHODS: The subjects were 12 healthy male volunteers aged between 20-40 years. A single, oral starting dose of nefazodone or trazodone was administered in a double-blind, randomized latin-square design with a 1-week interval between each drug switch. Psychomotor performances were assessed at 1 hour before and at 2 hours after administration of nefazodone 50 mg, nefazodone 100 mg or trazodone 50 mg. The measures of psychomotor performance included Vienna Determination Unit for complex choice reaction time, Critical Flicker Fusion Test, and Grooved Pegboard Test. RESULTS: In the Vienna Determination Unit, when 'within drug effect' (pre- vs. post-medication) was analyzed, nefazodone 100 mg decreased complex choice reaction time in both subtest 2 and subtest 3. Nefazodone 50 mg also decreased the reaction time in subtest 3 but not in subtest 2 which was more difficult and demanding task than subtest 3. On the other hand, no significant changes in the reaction time were observed with trazodone 50 mg in either subtest 2 or subtest 3. When 'between drug effect' was analyzed, however, the differences between drugs were not found to reach statistically significant level. No significant 'between drug effect' or 'within drug effect' was observed in Critical Flicker Fusion Test and Grooved Pegboard Test. CONCLUSION: Although the differences between nefazodone and trazodone did not reach statistically significant level, the results on the complex choice reaction time suggest that al least a single starting dose of nefazodone up to 100 mg does not impair psychomotor performances and it might have a less detrimental effect than trazodone on the psychomotor performance.