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Dive into the research topics where Naoyuki Katagiri is active.

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Featured researches published by Naoyuki Katagiri.


Psychiatry and Clinical Neurosciences | 2011

Cerebral blood flow changes in very-late-onset schizophrenia-like psychosis with catatonia before and after successful treatment.

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.


Schizophrenia Bulletin | 2017

Reduced Thickness of the Anterior Cingulate Cortex in Individuals With an At-Risk Mental State Who Later Develop Psychosis

Yoichiro Takayanagi; Sue Kulason; Daiki Sasabayashi; Tsutomu Takahashi; Naoyuki Katagiri; Atsushi Sakuma; Chika Obara; Mihoko Nakamura; Mikio Kido; Atsushi Furuichi; Yumiko Nishikawa; Kyo Noguchi; Kazunori Matsumoto; Masafumi Mizuno; J. Tilak Ratnanather; Michio Suzuki

BACKGROUND Despite the fact that only a part of the individuals with at-risk mental state (ARMS) for psychosis do develop psychosis, biological markers of future transition to psychosis have not been well documented. Structural abnormality of the anterior cingulate gyrus (ACG), which probably exists prior to the onset of psychosis, could be such a risk marker. METHODS We conducted a multicenter magnetic resonance imaging (MRI) study of 3 scanning sites in Japan. 1.5-T 3D MRI scans were obtained from 73 ARMS subjects and 74 age- and gender-matched healthy controls. We measured thickness, volume, and surface area of the ACG using labeled cortical distance mapping and compared these measures among healthy controls, ARMS subjects who later converted to overt psychosis (ARMS-C), and those who did not (ARMS-NC). RESULTS Seventeen of 73 (23%) ARMS subjects developed overt psychosis within the follow-up period. The thickness of the left ACG was significantly reduced in ARMS-C relative to healthy subjects (P = .026) while both ARMS-C (P = .001) and ARMS-NC (P = .01) had larger surface areas of the left ACG compared with healthy controls. CONCLUSION Further studies will be needed to identify potential markers of future transition to psychosis though cortical thinning of the ACG might be one of the candidates.


Comprehensive Psychiatry | 2016

Characteristics of motivation and their impacts on the functional outcomes in patients with schizophrenia

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

Longitudinal study examining abnormal white matter integrity using a tract-specific analysis in individuals with a high risk for psychosis

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

School mental healthcare services using internet‐based cognitive behaviour therapy for young male athletes in Japan

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

Stigma toward psychosis and its formulation process: prejudice and discrimination against early stages of schizophrenia

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.


Rivista Di Neuroradiologia | 2009

Dyke-Davidoff-Masson Syndrome Demonstrated by Current MR images A Case Report

Masaaki Hori; Masafumi Mizuno; Naoyuki Katagiri; Kiyoaki Takeshi; Naohisa Tsujino; Araki T; Nobuyuki Shiraga

Current magnetic resonance imaging techniques demonstrated MR findings of Dyke-Davidoff-Masson syndrome in a 44-year-old man. Statistical parametric mapping analysis of the T1-weighted images showed focal atrophy in the basal ganglia. Three-dimensional white matter fibers of corticospinal tracts, corpus callosum and cingulate bundle were demonstrated using diffusion tensor data correlated to the patients clinical conditions.


European Archives of Psychiatry and Clinical Neuroscience | 2018

Surface morphology of the orbitofrontal cortex in individuals at risk of psychosis: a multicenter study

Mihoko Nakamura; Tsutomu Takahashi; Yoichiro Takayanagi; Daiki Sasabayashi; Naoyuki Katagiri; Atsushi Sakuma; Chika Obara; Shinsuke Koike; Hidenori Yamasue; Atsushi Furuichi; Mikio Kido; Yumiko Nishikawa; Kyo Noguchi; Kazunori Matsumoto; Masafumi Mizuno; Kiyoto Kasai; Michio Suzuki

Changes in the surface morphology of the orbitofrontal cortex (OFC), such as a fewer orbital sulci and altered sulcogyral pattern of the ‘H-shaped’ orbital sulcus, have been reported in schizophrenia, possibly reflecting abnormal neurodevelopment during gestation. However, whether high-risk subjects for developing psychosis also exhibit these gross morphologic anomalies is not well documented. This multicenter MRI study from four scanning sites in Japan investigated the distribution of the number of intermediate and posterior orbital sulci, as well as the OFC sulcogyral pattern, in 125 individuals with an at-risk mental state (ARMS) [of whom 22 later developed psychosis (ARMS-P) and 89 did not (ARMS-NP)] and 110 healthy controls. The ARMS group as a whole had a significantly lower number of intermediate and posterior orbital sulci compared with the controls, which was associated with prodromal symptomatology. However, there was no group difference in OFC pattern distribution. The ARMS-P and -NP groups did not differ in OFC surface morphology. These results suggest that gross morphology of the OFC in high-risk subjects may at least partly reflect neurodevelopmental pathology related to vulnerability to psychosis.


Schizophrenia Research | 2018

Federated multi-site longitudinal study of at-risk mental state for psychosis in Japan

Kazunori Matsumoto; Masahiro Katsura; Naohisa Tsujino; Shimako Nishiyama; Takahiro Nemoto; Naoyuki Katagiri; Tsutomu Takahashi; Yuko Higuchi; Noriyuki Ohmuro; Hiroo Matsuoka; Michio Suzuki; Masafumi Mizuno

There has been recent accumulation of evidence and clinical guidance regarding the at-risk mental state (ARMS) for psychosis. However, most studies have been observational cohort and intervention studies of Western populations. To assess the validity of the ARMS concept and the transition rate to psychosis in a non-Western nation, we retrospectively combined and analyzed clinical data of individuals diagnosed with ARMS who were prospectively followed-up at three specialized clinical services for ARMS in Japan. In total, we included 309 individuals with ARMS, of whom 43 developed overt psychosis. We estimated cumulative transition rates to psychosis with the Kaplan-Meier method, obtaining rates of 12% at 12, 16% at 24, 19% at 36, and 20% at 48 months. Only two individuals reported past cannabis use. Despite several differences among the three sites, transition rates did not differ among them. Furthermore, the transition rate of children aged between 14 and 17 years did not differ from that of individuals aged 18 years or older. Regression analysis revealed that meeting the brief limited intermittent psychotic symptoms (BLIPS) criterion was associated with an increased risk of transition to psychosis, whereas genetic risk factors were not. Although antipsychotic prescription was relatively frequent in this cohort, there was no evidence supporting frequent use of antipsychotics for this population. In conclusion, our findings support the assertion that the current concept of ARMS is applicable in Japan. Development of local clinical guidelines and training for clinicians is necessary to disseminate this concept to more clinical settings.


Schizophrenia Bulletin | 2018

F238. COMPETENCE-PERFORMANCE DISCREPANCY IN SOCIAL FUNCTIONING IN PATIENTS WITH SCHIZOPHRENIA: THE IMPACT OF SOCIAL ANXIETY

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.

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