고위험군 및 초발 정신분열병 환자의 작업기억 관련 뇌 기능적 연결성의 변화

Dept. of Medicine/박사Higher cognitive functions require functional interactions between multiple specialized neuronal networks in the brain. Disturbances in functional connectivity have been proposed as a major pathophysiological mechanism for schizophrenia (SPR). In the present study, functional connectivity networks were explored using small-worldness and synchronization likelihood (SL) during a working memory task. Thirteen first-episode SPR patients, 11 UHR individuals, 13 healthy controls were recruited. EEG data were collected during a verbal 0- and 2-back task in all participants. For SL, there was significantly different pattern of change in UHR subjects and SPR patients as the working memory load varied (significant working memory load by group interaction, theta: p<0.001, F=21.768; alpha: p<0.001, F=22.779; beta: p<0.001, F=30.318, and gamma: p<0.001, F=17.452). Specifically, while SL significantly decreased as the working memory load increased in the controls (theta: p=0.017, alpha: p=0.003, beta: p=0.004, gamma: p=0.005), these working memory load effect was not observed in UHR subjects. In SPR patients, SL was significantly higher than controls or UHR during the 0-back task, but decreased as the working memory load increased (significant working memory load effect, theta: p<0.001, alpha: <0.001, beta: <0.001, gamma: <0.001). For small-worldness, a trend of the group effect was seen in the theta band (p=0.088, F=2.616), with decreased small-worldness in SPR patients compared to controls (p=0.031) as resulted from the pairwise comparisons. In correlation analyses, increased SL in UHR subjects was associated with lower working memory performance, lower neurocognitive function and more severe symptoms. These findings collectively support the disconnection hypothesis of schizophrenia and suggest an alteration of functional connectivity in the prodromal phase. These changes may be associated with impairments in functional trimming needed for modular specialization of brain networks for higher cognitive demands.ope

Synthesis and characterization of red emitting molecules and polymers showing aggregation-induced enhanced emission (AIEE)

학위논문(석사) --서울대학교 대학원 :재료공학부,2007.Maste

강박장애 환자에서 모호 얼굴 표정 자극에 대한 역겨움 및 분노 인식

Dept. of Medicine/석사[한글] 연구 목적 : 본 연구는 강박장애 환자에서 명확 얼굴표정 검사 및 모호 얼굴표정 검사를 이용하여 얼굴 표정 인식의 장애가 있는지, 특히 강박장애의 질병 모델에서 제시되고 있는 역겨움 정서에 대한 표정 인식 장애가 있는지를 살펴보고자 하였다. 연구 방법 : 연구대상은 강박장애 환자 41명과 정상 대조군 37명으로 하였다. 몰핑기법으로 만든 다양한 정서가를 가진 부정 정서의 얼굴 표정 사진을 사용하여, 70% 이상의 정서가를 가진 얼굴 표정을 제시하는 명확 과제와 50%의 정서가를 가진 얼굴 표정을 제시하는 모호 과제를 시행하였다. 연구결과 : 명확한 얼굴표정에 대하여 강박장애 환자군은 정산군과 정답율에서 차이를 보이지 않았다 (F=1.46, p=0.23). 모호 과제의 경우, 환자군은 모호한 얼굴 표정 사진에 대하여 역겨움 정서로 인식하는 경우가 정상 대조군에 비하여 유의미하게 많았으며 (F=5.1, p=0.03), 분노 정서로 인식하는 경우는 유의미하게 적었다 (F=5.9, p=0.02). 역겨움 정서에 대한 민감도를 측정하는 역겨움 척도에서 오염 관련 영역과 모호한 얼굴 표정 사진을 혐오 정서로 인식하는 경향이 양의 상관관계를 보였으며 (r=0.25, p=0.03), 분노 정서로 인식하는 경향이 음의 상관관계를 보였다 (r= -0.26, p=0.03). 결론 : 강박장애 환자들은 모호한 얼굴 표정 사진을 역겨움 정서로 인식하는 경향이 높았고, 분노로 인식하는 경향이 낮았다. 본 결과는 강박장애 환자들이 모호한 외부 자극을 역겨움 정서로 인식할 가능성이 높음을 시사한다. [영문] Objectives: The aim of this study is to examine the recognition of non-ambiguous and ambiguous facial expressions in OCD patients compared to normal controls, especially in relations to disgust recognition which has been implicated in the disease model of OCD. Methods: Forty-one patients with OCD and thirty-seven healthy controls performed the computerized emotion recognition task consisted of two paradigms, the non-ambiguous paradigm and the ambiguous paradigm. Morphed facial photographs of negative emotions of anger, disgust, fear and sadness were used. Results: There were no differences between the OCD patients and the normal controls in the frequency of correct identification of non-ambiguous facial expressions (F=1.46, p=0.23). In response to ambiguous facial expressions, OCD patients were more likely to perceive disgust (F=5.1, p=0.03) and less likely to perceive anger (F=5.9, p=0.02). Among the disgust domains, only the domain of Contamination-Based Disgust positively correlated with perception of ambiguous facial expression as disgust, specifically (r=0.25, p=0.03), while negatively correlating with anger (r= -0.26, p=0.03). Conclusion: OCD patients were significantly more likely to recognize ambiguous facial expressions as disgust. Current findings suggest that OCD patients might be more prone to perceiving stimuli as disgustful in ambiguous social context.ope

Norepinephrine transporter gene (SLC6A2) is involved with methylphenidate response in Korean children with attention deficit hyperactivity disorder

The purpose of this study was to investigate the association between the methylphenidate (MPH) response and the norepinephrine transporter (NET) gene polymorphisms in Korean children with attention deficit hyperactivity disorder (ADHD). One hundred and fourteen children with ADHD (mean age 9.08 ± 1.94 years) were recruited from a child psychiatric clinic in South Korea. The genomic DNA was extracted from the blood lymphocyte. Patients were administered MPH for 8 weeks. Good response was defined as a decrease of more than 50% from the baseline ADHD rating scale-IV scores or Clinical Global Impression-Severity score was 1 or 2 after treatment. We compared the MPH response according to the genotype of G1287A of the NET gene (SLC6A2). In patients with G/G genotype, 41 patients (71.9%) showed good response and 16 patients (28.1%) showed poor response when it was measured by the ADHD rating scale-IV. In comparison, 23 patients (46.0%) with G/A genotype and four patients (57.1%) with A/A genotype showed good response (P=0.018, by the Fisher's exact test). When we compared the response of MPH between patients with G/G genotype and those without G/G genotype, 41 patients (71.9%) with G/G genotype showed good response, whereas only 27 patients (46.4%) without G/G genotype showed good response. [Pearson χ² = 7.143, degrees of freedom (df)=1, P=0.008]. Our study found a significant association between the G1287A genotype of the NET gene and the MPH response in Korean children with ADHD. These findings support the significant role of the NET gene in ADHD treatment with MPH.ope

Abnormalities of emotional awareness and perception in patients with obsessive-compulsive disorder

BACKGROUND: Emotional awareness deficit may play a critical role in the production and maintenance of obsessive-compulsive symptoms and social dysfunction in patients with obsessive-compulsive disorder (OCD). The aim of this study was to investigate characteristics of emotional awareness such as empathy and alexithymia in OCD patients. In addition, we examined whether impaired emotional awareness measured by self-assessment questionnaires was associated with emotional facial recognition ability in OCD patients. METHODS: Study participants included 107 patients with OCD and 130 healthy age- and sex-matched volunteers. The Interpersonal Reactivity Index (IRI) and Toronto Alexithymia Scale-20 were applied as measures of empathy and alexithymia. A subset of 56 patients with OCD additionally performed the emotional perception task of face expression. RESULTS: Patients with OCD scored significantly lower for perspective taking, and significantly higher for personal distress of IRI, and significantly higher for alexithymia compared to normal controls. Impaired emotional awareness such as lower perspective taking and fantasy seeking had a perception bias towards disgust in response to ambiguous facial expressions in OCD patients. LIMITATIONS: The OCD group consisted of patients in different stages of the illness and with different degrees of severity. CONCLUSIONS: OCD involves the impairment of emotional awareness and perception and it may relate to social dysfunction and to impairments in the ability to shift naturally from obsessive thoughts to other thoughts in response to social situations in patients with OCD.ope

Influence of BDNF and COMT polymorphisms on emotional decision making

Decision making is an important brain function. Although little is known about the genetic basis of decision making, it has been suggested that it is mediated by the modulation of neurotransmitter systems. We investigated how the BDNF Val66Met and COMT Val158Met polymorphisms affect emotional decision making using the Iowa Gambling Task (IGT). One hundred sixty-eight healthy Korean college students (93 males, 75 females) with a complete dataset were included in the data analysis. The IGT and genotyping for the polymorphisms of BDNF Val66Met and COMT Val158Met were performed. Both Met/Met and Val/Met of the BDNF Val66Met polymorphism were significantly associated with a lower mean score of blocks 3-5 of the IGT and with less improvement from block 1 to block 3-5 than the Val/Val. However, the BDNF was not significantly associated with the score of block 1, and the COMT Val158Met polymorphism produced no significant effect on IGT performance. No interaction effect was observed between the BDNF and the COMT for the IGT. These findings suggest the BDNF Val66Met may affect the emotional decision making performanceope

Perception bias of disgust in ambiguous facial expressions in obsessive-compulsive disorder

Impaired recognition of facial expressions of disgust has been suggested for patients with obsessive-compulsive disorder (OCD). This study aimed to compare the perception of negative emotions by OCD patients and controls using both non-ambiguous and ambiguous facial expressions. Forty-one OCD patients and thirty-seven controls performed the computerised emotion perception task. There were no differences between OCD patients and controls in the frequency of correct identification of non-ambiguous facial expressions. However, OCD patients were more likely to perceive disgust and less likely to perceive anger in response to ambiguous facial expressions when controlling for covariates. In OCD patients, a higher cleaning dimension was associated with a lower perception of anger and a higher perception of disgust when presented with ambiguous facial expressions. The domains of core disgust and contamination-based disgust domains of disgust sensitivity were positively correlated with the perception of ambiguous facial expressions as disgust, as well as cleaning symptom dimension scores. Our findings suggest that OCD patients, particularly those with higher washing/contamination symptoms, are more likely to perceive disgust in ambiguous facial expressionsope

Psychometric analysis of the Korean version of the Disgust Scale-Revised.

OBJECTIVE: Disgust is a basic emotion associated with feelings of revulsion and withdrawal behaviors from dangerous situations. The aim of this study was to examine the psychometric properties of the Disgust Scale--Revised (DS-R), a tool designed to measure individuals' responses to various disgust-provoking situations, among Korean populations. METHODS: A sample of 1117 healthy volunteers completed self-report questionnaires containing the 27-item DS-R. A subsample (n = 231) completed the Temperament and Character Inventory (TCI), Eysenck Personality Questionnaire (EPQ), and State-Trait Anxiety Inventory (STAI). Principal component analysis using a varimax rotation was conducted. Construct validity was assessed using Pearson correlation analysis for the TCI, EPQ, and STAI. To examine differences in responses on the DS-R among populations, patients with obsessive-compulsive disorder were compared with healthy subjects who were matched with respect to age and sex. RESULTS: The Cronbach α estimates for total items and the 3 original subscales of the DS-R, including: core disgust, animal reminder disgust, and contamination-based disgust, were 0.86, 0.77, 0.80, and 0.55, respectively. Principal component analysis identified 5 factors, which accounted for 48% of the total variance of the scale. The 5 newly developed dimensions were labeled as core disgust-touch, core disgust-dirt, contamination-based disgust, animal reminder disgust, and social intolerance disgust. The Cronbach α coefficients were 0.79, 0.64, 0.46, 0.77, and 0.34, respectively, for these subscales. The DS-R was correlated positively with harm avoidance from the TCI, neuroticism from the EPQ, and the anxiety scores of STAI. Furthermore, the contamination-based disgust scores for patients with obsessive-compulsive disorder were higher than those of normal controls. CONCLUSION: The DS-R may be a reliable, valid, and acceptable tool to measure disgust sensitivity among Korean populations. The psychometric properties of the Korean version of the DS-R and the original DS-R are discussed.ope