Publications by authors named "Ryo Ochi"

Aim: Although numerous studies have reported that chronic alcohol consumption causes brain volume reduction and cerebrospinal fluid volume increase, few studies have examined the acute effects of alcohol on brain structure. This study aims to investigate the short-term brain volume changes following alcohol administration.

Methods: Moderate doses of alcohol were administered intravenously to 18 healthy volunteers for a total of 90 min to achieve a blood alcohol concentration of 0.

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Background: To elucidate the neurobiology underlying alcohol's effect on the human brain, we examined the acute effects of moderate alcohol administration on levels of glutamatergic neurometabolites and N-acetylaspartate, an amino acid found in neurons, may reflect disordered neuronal integrity.

Methods: Eighteen healthy Japanese participants (7 males/11 females) aged 20-30 years who were heterozygous for an inactive allele of acetaldehyde dehydrogenase-2 (ALDH/*1/*2) were included. Participants underwent an intravenous alcohol infusion using the clamp method at a target blood alcohol concentration (BAC) of 0.

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Background And Hypothesis: Given the heterogeneity and possible disease progression in schizophrenia, identifying the neurobiological subtypes and progression patterns in each patient may lead to novel biomarkers. Here, we adopted data-driven machine-learning techniques to identify the progression patterns of brain morphological changes in schizophrenia and investigate the association with treatment resistance.

Study Design: In this cross-sectional multicenter study, we included 177 patients with schizophrenia, characterized by treatment response or resistance, with 3D T1-weighted magnetic resonance imaging.

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Acute alcohol administration affects functional connectivity, yet the underlying mechanism is unknown. Previous work suggested that a moderate dose of alcohol reduces the activity of gamma-aminobutyric acidergic (GABAergic) interneurons, thereby leading to a state of pyramidal disinhibition and hyperexcitability. The present study aims to relate alcohol-induced changes in functional connectivity to regional genetic markers of GABAergic interneurons.

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Background: Abnormalities in the anterior cingulate cortex (ACC) are thought to play an important role in the pathophysiology of schizophrenia. Given regional variations in ACC structure, the present study aimed to examine ACC structural subdivisions and their relationships to treatment resistance and glutamatergic levels in schizophrenia.

Methods: This study included 100 patients with schizophrenia and 52 healthy controls from 2 cohorts.

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Background: Resilience is a crucial factor preventing the onset of mental illness and contributing to the well-being and healthy longevity, whose neural bases are not fully elucidated in older people. The present study aimed to identify the cortical thickness associating with resilience in older adults.

Methods: This is a part of the cross-sectional Arakawa geriatric cohort study for people aged 65 years or older, consisting of 1001 individuals.

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Sleep disturbance is a common symptom of psychiatric and neurodevelopmental disorders and, especially in childhood, can be a precursor to various mental disorders. However, the genetic etiology of mental illness that contributes to sleep disturbance during childhood is poorly understood. We investigated whether the polygenic features of psychiatric and neurodevelopmental disorders are associated with sleep disturbance during childhood.

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Despite previous neuroimaging studies demonstrating morphological abnormalities of the thalamus and other subcortical structures in patients with schizophrenia, the potential role of the thalamus and its subdivisions in the pathophysiology of this illness remains elusive. It is also unclear whether similar changes of these structures occur in individuals at high risk for psychosis. In this study, magnetic resonance imaging was employed with the Multiple Automatically Generated Templates (MAGeT) brain segmentation algorithm to determine volumes of the thalamic subdivisions, the striatum (caudate, putamen, and nucleus accumbens), and the globus pallidus in 62 patients with schizophrenia, 38 individuals with an at-risk mental state (ARMS) [4 of whom (10.

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Previous diffusion tensor imaging (DTI) studies have reported white matter alterations in patients with schizophrenia. Notably, one third of this population does not respond to first-line antipsychotics and is thus referred to as treatment-resistant schizophrenia (TRS). Despite potentially distinct neural bases between TRS and non-TRS, few studies have compared white matter integrity between these groups.

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Aim: Stress-related disorders and severe stress exposure can cause atrophy of the whole hippocampus and its subfields. However, the impact of stress coping strategies on the hippocampus remains unclear. Therefore, we aimed to examine the relation between approach- and avoidance-oriented coping strategies and hippocampal volume in elderly persons.

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