Toyosaku Ota

Tai Chi exercise versus rehabilitation for the elderly with cerebral vascular disorder: a single-blinded randomized controlled trial

Background:  Cerebral vascular disorder (CVD) might result in a quantifiable decrease in quality of life, which is determined not only by the neurological deficits but also by impairment of cognitive functions. There are few studies that report on the cognitive effect of Tai Chi exercise (Tai Chi) on the elderly with CVD. The purpose of the present study was to examine the cognitive effect of Tai Chi on the elderly with CVD using P300 measurement, in addition to the General Health Questionnaire (GHQ) and Pittsburgh Sleep Quality Index (PSQI).

Lower prefrontal activity in adults with obsessive-compulsive disorder as measured by near-infrared spectroscopy

Recent developments in near-infrared spectroscopy (NIRS) have enabled the non-invasive elucidation of the neurobiological underpinnings of psychiatric disorders. Functional neuroimaging studies in human patients have suggested that the frontal cortex and subcortical structures may play a role in the pathophysiology of obsessive-compulsive disorder (OCD). Here we used NIRS to investigate neurobiological function in 12 patients with OCD and 12 age- and sex-matched, healthy control subjects. The relative concentrations of oxyhemoglobin (oxy-Hb) were measured with prefrontal probes every 0.1 s, during performance of a Stroop color-word task, using 24-channel NIRS. Oxy-Hb changes in the prefrontal cortex of the OCD group were significantly smaller than those in the control group, especially in the left lateral prefrontal cortex. These results suggest that patients with OCD have reduced prefrontal hemodynamic responses as measured by NIRS.

Effects of osmotic-release methylphenidate in attention-deficit/hyperactivity disorder as measured by event-related potentials

Aim:  Attention‐deficit/hyperactivity disorder (ADHD) is a relatively common central nervous system disorder in school‐age children, which may involve a specific disorder in cognition and/or information processing. Event‐related potentials (ERP) are commonly used as physiological measures of cognitive function as they are easily measured and non‐invasive. Thus, in the present study, we examined the effects of osmotic‐release methylphenidate (MPH) (Concerta), a common treatment for childhood attention‐deficit/hyperactivity disorder (ADHD), in ADHD children as measured by ERP.

Differential patterns of blood oxygenation in the prefrontal cortex between patients with methamphetamine-induced psychosis and schizophrenia

Despite some slight differences in symptomatology, differential diagnosis of methamphetamine-induced psychosis (MAP) versus schizophrenia can be challenging because both disorders present a large overlap in their clinical symptoms. However, a recent study has shown that near-infrared spectroscopy (NIRS) performed during a cognitive task can be a powerful tool to differentiate between these two disorders. Here, we evaluated verbal fluency task performance during NIRS in 15 patients diagnosed with MAP and 19 with schizophrenia matched for age and sex. We used prefrontal probes and a 24-channel NIRS machine to measure the relative concentrations of oxyhaemoglobin every 0.1 s during the task. For each patient, the neurocognitive function and clinical psychopathology were evaluated using the Positive and Negative Symptom Scale (PANSS), and the Brief Assessment of Cognition in Schizophrenia (BACS). Oxyhaemoglobin changes in the prefrontal cortex were significantly higher in the MAP group compared to those in the schizophrenia group, particularly in the right dorsolateral prefrontal cortex. In contrast, we found no significant difference in PANSS and BACS scores. Our findings suggest that NIRS measurement could be applied to differentiate patients with MAP from those with schizophrenia, even in cases where clinical symptoms are similar.

Event-related potentials in drug-naïve pediatric patients with obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) is one of the most common mental health disorders, characterized by obsessive thoughts and/or compulsive behaviors, which may involve specific disorders in cognition and/or information processing. Event-related potentials (ERPs) are commonly used as physiological measures of cognitive function as they are easily measured and noninvasive. In the present study, 20 drug-naïve pediatric patients with OCD were compared with 20 healthy control participants who were age- and sex-matched to perform the ERP. Based on the guidelines for evoked potential measurement, the P300 and mismatch negativity (MMN) were obtained by auditory odd-ball tasks. We found that the amplitudes of the P300 components in the Fz, Cz, Pz, C3, and C4 regions were significantly smaller in the OCD group compared with the control group. There were no between-group differences in P300 latency, MMN amplitude, or MMN latency. Moreover, we found significant correlations between scores on the Childrens Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) and P300 amplitudes at Cz, Pz, and C3. The present study is the first to report smaller P300s and the associations between P300 abnormalities and CY-BOCS scores.

Event-related potentials reflect the efficacy of pharmaceutical treatments in children and adolescents with attention deficit/hyperactivity disorder.

Few objective biological measures of pharmacological treatment efficacy exist for attention deficit/hyperactivity disorder (ADHD). Although we have previously demonstrated that event-related potentials (ERPs) reflect the effects of osmotic-release methylphenidate in treatment of naïve pediatric patients with ADHD, whether this is true for the therapeutic effects of atomoxetine (ATX) is unknown. Here, we used the Japanese version of the ADHD rating-scale IV to evaluate 14 patients with ADHD, and compared their ERP data with 14 age- and sex-matched controls. We measured P300 and mismatch negativity (MMN) components during an auditory oddball task before treatment (treatment naïve) and after 2 months of ATX treatment. Compared with controls, P300 components at baseline were attenuated and prolonged in the ADHD group at Fz (fronto-central), Cz (centro-parietal), Pz (parietal regions), C3 and C4 electrodes. ATX treatment reduced ADHD symptomology, and after 2 months of treatment, P300 latencies at Fz, Cz, Pz, C3, and C4 electrodes were significantly shorter than those at baseline. Moreover, MMN amplitudes at Cz and C3 electrodes were significantly greater than those at baseline. Thus, ERPs may be useful for evaluating the pharmacological effects of ATX in pediatric and adolescent patients with ADHD.

Comparison of pervasive developmental disorder and schizophrenia by the Japanese version of the National Adult Reading Test

Abstract Objective. In adults, it is sometimes difficult to discriminate between pervasive developmental disorder (PDD) and schizophrenia (SCH) when positive symptoms are not outstanding. We examined whether the Japanese version of the National Adult Reading Test (JART), is a valid scale for evaluating pre-morbid intelligence quotient (IQ) in patients with SCH, and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) are useful for helping to discriminate between PDD and SCH. Methods. Sixteen patients with adult PDD and 16 age-, education- and sex-matched patients with SCH participated in the present study. In addition, two groups were matched for JART and GAF scores. All subjects were scored on the JART and WAIS-R after informed consent on the aim of this study. Examiners who were blind to the diagnoses measured JART and WAIS-R. Results. Significant diagnosis-by-IQ examination interactions were found (F[1,30] = 10.049, P = 0.003). Furthermore, WAIS-R scores of the PDD group were higher than those of the SCH group (P = 0.002) considering two groups were matched for JART. Conclusions. The comparison of IQ in the PDD group and in the SCH group by JART and WAIS-R might be an easy and useful method for helping to discriminate between PDD and SCH.

Reduced Prefrontal Cortex Hemodynamic Response in Adults with Methamphetamine Induced Psychosis: Relevance for Impulsivity.

Patients with methamphetamine abuse/dependence often exhibit high levels of impulsivity, which may be associated with the structural abnormalities and functional hypoactivities observed in the frontal cortex of these subjects. Although near-infrared spectroscopy (NIRS) is a simple and non-invasive method for characterizing the clinical features of various psychiatric illnesses, few studies have used NIRS to directly investigate the association between prefrontal cortical activity and inhibitory control in patients with methamphetamine-induced psychosis (MAP). Using a 24-channel NIRS system, we compared hemodynamic responses during the Stroop color-word task in 14 patients with MAP and 21 healthy controls matched for age, sex and premorbid IQ. In addition, we used the Barrett Impulsivity Scale-11 (BIS-11) to assess impulsivity between subject groups. The MAP group exhibited significantly less activation in the anterior and frontopolar prefrontal cortex accompanied by lower Stroop color-word task performance, compared with controls. Moreover, BIS-11 scores were significantly higher in the MAP group, and were negatively correlated with the hemodynamic responses in prefrontal cortex. Our data suggest that reduced hemodynamic responses in the prefrontal cortex might reflect higher levels of impulsivity in patients with MAP, providing new insights into disrupted inhibitory control observed in MAP.

Paliperidone extended release for the treatment of pediatric and adolescent patients with Tourette's disorder.

ObjectiveA subgroup of patients with Tourettes disorder (TD) has symptoms refractory to haloperidol, a standard therapeutic drug for TD.MethodsWe report on three cases of pediatric and adolescent patients who were treated with paliperidone extended release.ResultsIn two cases, TD symptoms were remarkably improved by switching from haloperidol to paliperidone extended release, and in another case, paliperidone extended release showed significant efficacy in treating TD symptoms as the first-line drug. In all cases, no significant adverse side effects were detected.ConclusionPaliperidone extended release may be a strong candidate for the treatment of pediatric and adolescent patients with TD.

A longitudinal event-related potential study of selective serotonin reuptake inhibitor therapy in treatment-naïve pediatric obsessive compulsive disorder patients

Obsessive-compulsive disorder (OCD) is characterized by obsessive thoughts and/or compulsive behaviors, involving specific cognition and/or information processing disorders. Event-related potentials (ERPs) are commonly used as physiological measures of cognitive function. In conscious patients, ERPs are easily and non-invasively measured. Previous ERP studies have revealed differences between OCD patients and control subjects. Whether ERPs reflect the pharmacological effects of OCD treatment, particularly in treatment-naïve pediatric patients, remains unknown. We used the Childs Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) to evaluate the symptomatic severity of 12 treatment-naïve pediatric OCD patients. Comparisons were made with 12 age-, sex-, and intelligence-matched controls. The P300 and mismatch negativity (MMN) components were measured during an auditory odd-ball task at baseline in both groups and after the 3-year serotonin reuptake inhibitor (SSRI) treatment in OCD patients. Compared with controls, P300 amplitudes were smaller n the OCD group at Fz, Cz, Pz, C3, and C4. After SSRI treatment, P300 amplitudes increased partly at Fz and C4 in association with symptomatic improvements. We found a significant positive correlation between P300 amplitude in C4 and CY-BOCS scores. Our findings confirm the utility of SSRIs in pediatric OCD, and suggest the utility of ERPs for evaluating pharmacological effects in treatment-naïve pediatric OCD patients.