Taiju Yamaguchi
Toho University
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Featured researches published by Taiju Yamaguchi.
Psychiatry and Clinical Neurosciences | 2011
Naohisa Tsujino; Takahiro Nemoto; Taiju Yamaguchi; Naoyuki Katagiri; Nao Tohgi; Ryu Ikeda; Nobuyuki Shiraga; Sunao Mizumura; Masafumi Mizuno
The purpose of the present study was to investigate regional cerebral blood flow (rCBF) changes in a patient with very‐late‐onset schizophrenia‐like psychosis (VLOS) with catatonia. A 64‐year‐old woman developed catatonia after experiencing persecutory delusions. The patients rCBF was examined using single photon emission computed tomography (SPECT) with easy Z‐score imaging system. Before treatment, hypoperfusion was observed in the striatum and the thalamus, whereas hyperperfusion was observed in the left lateral frontal cortex and the left temporal cortex. After treatment, the disproportions in rCBF disappeared, and hyperperfusion was observed in the motor cortex. Sequential SPECT findings suggest that rCBF abnormalities may be correlated with the symptomatology of catatonia in patients with VLOS.
Comprehensive Psychiatry | 2016
Miki Tobe; Takahiro Nemoto; Naohisa Tsujino; Taiju Yamaguchi; Naoyuki Katagiri; Chiyo Fujii; Masafumi Mizuno
BACKGROUND Deficits of motivation have been considered to be a core feature of schizophrenia, and recent studies have begun to reveal the biological and psychological characteristics and mechanisms underlying the deficits in motivation in schizophrenia patients. The aims of the present study were to investigate the characteristics of motivation in schizophrenia patients using the General Causality Orientations Scale (GCOS), and the impacts of motivational orientations on the functional outcomes in schizophrenia patients. METHODS A total of 53 outpatients with schizophrenia and 38 healthy controls were recruited for this study. The GCOS was used to assess individual tendencies in respect of three different motivational orientations: the autonomy, controlled, and impersonal orientations, corresponding to intrinsic motivation, extrinsic motivation, and amotivation, respectively. The cognitive functioning, psychiatric symptoms, social functioning, and quality of life of the subjects were also assessed. RESULTS The score for autonomy orientation was significantly lower in the patient group than that in the control group, while no significant differences were found between the two groups in respect of the scores for the other two orientations. The autonomy orientation was associated with various clinical variables, and regression analysis identified as one of the variables with the highest predictive accuracy for social functioning. CONCLUSIONS Intrinsic motivation measured by the GCOS in schizophrenia patients was significantly lower than that in healthy controls. The deficits of intrinsic motivation were broadly associated with the clinical features and were a determinant of social functioning. Development of treatments for enhancing intrinsic motivation would be essential for functional recovery in schizophrenia patients.
Psychiatry and Clinical Neurosciences | 2017
Junichi Saito; Masaaki Hori; Takahiro Nemoto; Naoyuki Katagiri; Keigo Shimoji; Shinya Ito; Naohisa Tsujino; Taiju Yamaguchi; Nobuyuki Shiraga; Shigeki Aoki; Masafumi Mizuno
Although volume reductions in the grey matter have been previously observed in individuals with an at‐risk mental state (ARMS) for psychosis, the features of white matter integrity and their correlation with psychiatric symptoms remain unclear.
Early Intervention in Psychiatry | 2017
Ryo Sekizaki; Takahiro Nemoto; Naohisa Tsujino; Chieko Takano; Chie Yoshida; Taiju Yamaguchi; Naoyuki Katagiri; Yutaka Ono; Masafumi Mizuno
Preventive intervention and treatment using internet‐based cognitive behaviour therapy (iCBT) can be easily administered to school students, as they are quite familiar with internet tools. This study aims to investigate the effectiveness and contribution of iCBT to mental healthcare in a school setting.
Comprehensive Psychiatry | 2017
Yoko Baba; Takahiro Nemoto; Naohisa Tsujino; Taiju Yamaguchi; Naoyuki Katagiri; Masafumi Mizuno
BACKGROUND Stigma toward psychosis can prevent social attendance and help-seeking behavior. Early detection and intervention has been shown to improve patient outcome in schizophrenia. The aim of this study was to reveal the characteristics and formulation process of stigma toward each clinical stage of schizophrenia, taking peoples backgrounds into consideration. METHODS The participants consisted of three groups: general public, patients with mental illness, and psychiatric professionals. We performed a survey examining stigmas toward people with psychotic-like-experiences (PLE), at-risk mental state for psychosis (ARMS), schizophrenia, or depression. Prejudice was measured using a 21-item questionnaire, and discrimination was measured using the Social Distance Scale. RESULTS The participants consisted of 149 people from the general public, 97 patients, and 119 psychiatric professionals. Generally, a similar pattern was observed among the groups in which prejudice and discrimination against PLE was mildest, followed by that against ARMS and depression, and finally schizophrenia. When the stigma of the general public was compared with that of psychiatric professionals, the prejudice and discrimination against PLE of the general public were both lower than those of the psychiatric professionals. However, the prejudice of the general public was stronger than that of the professionals for ARMS. Furthermore, the discrimination of the general public was stronger than that of the professionals for schizophrenia. CONCLUSIONS The stigmas of mental illness differed according to the clinical stage, although the pattern of severity was similar among the three groups. A formulation process is suggested in which stigma toward schizophrenia develops from an attitudinal property (prejudice) against ARMS and a behavioral property (discrimination) against schizophrenia.
Schizophrenia Bulletin | 2018
Takahiro Nemoto; Takashi Uchino; Sayaka Aikawa; Tomoyuki Funatogawa; Hiroshi Matsumoto; Taiju Yamaguchi; Naoyuki Katagiri; Naohisa Tsujino; Kei Sakuma; Masafumi Mizuno
Abstract Background Social functioning deficits are of critical importance in patients with schizophrenia, because they affect the long-term outcomes and quality of life (QOL) of the patients. Two aspects of social functioning, namely, competence (ability to perform skilled activities, that is, what one can do) and performance (actual performance of skilled activities, that is, what one actually does) are considered to have a significant influence on how well the patients can live independently in the community. Although the two aspects are usually thought to go hand in hand, discrepancy between the two is often observed in patients with schizophrenia in clinical practice. Some patients are not able to function in the community to the best of their ability; some patients appear to get along everyday living better than they would be expected to. The aim of the present study was to identify factors influencing the occurrence of such discrepancy of social functioning in patients with schizophrenia. Methods A total of 205 stable outpatients with schizophrenia aged 40 years old or under were recruited at the Toho University Omori Medical Center, Tokyo. Of the 205 patients, 100 were male (48.8%) and 105 (51.2%) were female. The mean age of the participants was 29.3 years and the mean estimated premorbid IQ was 100.8. The mean age at disease onset was 22.0 years old, and the mean duration of illness at the start of the study was 6.7 years. The social functioning, psychiatric symptoms, social anxiety, cognitive function, and QOL of the participants were assessed. The patients were divided into 4 groups by the cutoff points for competence and performance calculated using a comprehensive dataset of the Social Functioning Scale (SFS) obtained from multiple facilities. Results The subjects were divided according to their level of competence and performance as follows: good competence and good performance (CP) group, 108 (52.7%) patients; good competence but poor performance (Cp) group, 40 (19.5%) patients; poor competence but good performance (cP) group, 13 (6.3%) patients; poor competence and poor performance (cp) group, 44 (21.5%) patients. Among the 4 groups, the objects of particular interest in this study were the differences between CP and Cp groups and between the cP and cp groups. One-way ANOVA revealed significant differences among the groups in the scores on the Positive and Negative Syndrome Scale (PANSS), Liebowitz Social Anxiety Scale (LSAS), Global Assessment of Functioning Scale (GAF), World Health Organization-Quality of Life 26 (WHOQOL26), and Social Functioning Scale (SFS). Post-hoc comparisons revealed that the PANSS negative symptoms and general psychopathology scores, GAF score, WHOQOL26 score, and SFS total score were significantly worse in the Cp group than in the CP group, and that the LSAS score, GAF score, WHOQOL26 score, and SFS total score were significantly better in the cP group than in the cp group. Discussion In patients who are capable of living well in the community but do not perform well, negative symptoms may be involved in this discrepancy of social functioning. Patients who are able to maintain themselves well despite their poor social competence appear to have milder social anxiety symptoms as compared to patients who are neither competent nor capable of performing well in terms of social functioning in the community. Suitable and personalized approaches based on the patients’ profile of dysfunction would seem to be indispensable for the recovery of such patients.
Psychiatry and Clinical Neurosciences | 2018
Naohisa Tsujino; Hiromi Tagata; Yoko Baba; Akiko Kojima; Taiju Yamaguchi; Naoyuki Katagiri; Takahiro Nemoto; Masafumi Mizuno
The importance of early intervention in psychiatry is widely recognized among psychiatrists. However, it is unknown whether precise knowledge of at‐risk mental state has been disseminated. With this survey, we aimed to reveal how Japanese psychiatrists diagnose patients with at‐risk mental state and prescribe treatment strategies for them.
Psychiatry Research-neuroimaging | 2018
Sayaka Aikawa; Hiroyuki Kobayashi; Takahiro Nemoto; Satoshi Matsuo; Yo Wada; Noriyuki Mamiya; Taiju Yamaguchi; Naoyuki Katagiri; Naohisa Tsujino; Masafumi Mizuno
Social anxiety is commonly reported as a comorbid condition among people with schizophrenia. The aims of this study were to elucidate the associations between demographic/clinical features and social anxiety. A total of 207 outpatients with schizophrenia underwent assessments for social anxiety, psychiatric symptoms, social cognition, cognitive function, social functioning, and quality of life (QOL). To confirm the prediction model for social anxiety, we conducted multiple linear regressions using the Liebowitz Social Anxiety Scale (LSAS) score as an outcome variable and demographic/clinical variables as predictors. Of the 207 patients, 30 (14.5%) met the criteria for social anxiety disorder and 109 (52.7%) had a mean LSAS score higher than 30, suggesting that their social anxiety symptoms had reached a clinical level. Social anxiety was significantly correlated with psychiatric symptoms, social functioning, and QOL, whereas significant correlations with social cognition and cognitive function were not observed. A multiple regression analysis identified social functioning, gender, age of onset, and duration of untreated psychosis (DUP) as predictors that were most closely associated with the LSAS score. We confirmed that social anxiety symptoms were highly prevalent among outpatients with schizophrenia and were closely associated with social functioning and DUP, rather than social cognitive impairments.
Annals of General Psychiatry | 2015
Taiju Yamaguchi; Chiyo Fujii; Takahiro Nemoto; Naohisa Tsujino; Kiyoaki Takeshi; Masafumi Mizuno
BackgroundIn cases of untreated schizophrenia, the patients’ entourage often does not recognize the psychotic symptoms of the patient and the possibility that the patient may attempt suicide. The aim of this study was to investigate the discrepancies between the subjective experiences and observed behaviors in near-fatal suicide attempters with untreated schizophrenia.MethodsA semi-structured interview was carried out with seven near-fatal suicide attempters with untreated schizophrenia to examine the subjective experiences at the time of the suicide attempt. The families of the patients were also interviewed to determine their recognition of the patients’ psychotic symptoms and the suicidal ideation. The interview data were analyzed qualitatively.ResultsSix subjects were undergoing exacerbation of the psychotic symptoms at the time of exhibiting the suicide-related ideation. One subject had been in a prolonged depressive state before attempting suicide. Although all the patients experienced severe distress due to psychotic symptoms and depressive mood, they all exhibited only low level or no help-seeking behavior, and six of seven families had not recognized the change in the patient’s mental condition.ConclusionsAppropriate information about schizophrenia should be provided to the general public so that any help-seeking by the patients with this disease is not overlooked. In addition, accessible early intervention services for psychosis should be established.
Schizophrenia Research | 2015
Naoyuki Katagiri; Christos Pantelis; Takahiro Nemoto; Andrew Zalesky; Masaaki Hori; Keigo Shimoji; Junichi Saito; Shinya Ito; Dominic Dwyer; Issei Fukunaga; Keiko Morita; Naohisa Tsujino; Taiju Yamaguchi; Nobuyuki Shiraga; Shigeki Aoki; Masafumi Mizuno