Masaki Nishida | Jichi Medical University (original) (raw)

Papers by Masaki Nishida

Leprosy Review, Sep 1, 2006

Prevalence and characteristics of depression in mild cognitive impairment: the Sydney memory and ... more Prevalence and characteristics of depression in mild cognitive impairment: the Sydney memory and ageing study. Objective: Depression might be a risk factor for dementia. However, little is known about the prevalence of depressive symptoms in mild cognitive impairment (MCI) and whether mood or motivation-related symptoms are predominant. Method: A total of 767 non-demented community-dwelling adults aged 70-90 years completed a comprehensive assessment, including neuropsychological testing, and a past psychiatric ⁄ medical history interview. Depressive symptoms were assessed using the Geriatric Depression Scale (GDS) and Kessler Psychological Distress Scale (K10). Exploratory factor analysis was performed on the GDS and K10 to derive ÔmoodÕ and ÔmotivationÕ subscales. Results: A total of 290 participants were classified as having MCI and 468 as cognitively normal (CN). Participants with MCI reported more depressive symptoms, and more MCI participants met the cutoff for clinically significant symptoms, relative to CN participants. Those with amnestic MCI (aMCI), but not non-amnestic MCI, had more depressive symptoms and were more likely to meet the cutoff for clinically significant depressive symptoms, relative to CN participants. Participants with MCI reported more mood-related symptoms than CN participants, while there were no differences between groups on motivation-related symptoms. Conclusion: Individuals with MCI, especially aMCI, endorse more depressive symptoms when compared with cognitively intact individuals. These findings highlight the importance of assessing and treating depressive symptoms in MCI.

Clocks & Sleep

Daytime napping offers benefits for motor memory learning and is used as a habitual countermeasur... more Daytime napping offers benefits for motor memory learning and is used as a habitual countermeasure to improve daytime functioning. A single nap has been shown to ameliorate motor memory learning, although the effect of consecutive napping on motor memory consolidation remains unclear. This study aimed to explore the effect of daytime napping over multiple days on motor memory learning. Twenty university students were divided into a napping group and no-nap (awake) group. The napping group performed motor adaption tasks before and after napping for three consecutive days, whereas the no-nap group performed the task on a similar time schedule as the napping group. A subsequent retest was conducted one week after the end of the intervention. Significant differences were observed only for speed at 30 degrees to complete the retention task, which was significantly faster in the napping group than in the awake group. No significant consolidation effects over the three consecutive nap inte...

Scientific Reports, 2020

We recently demonstrated that sleeping on high rebound [HR] mattress toppers induced a continuous... more We recently demonstrated that sleeping on high rebound [HR] mattress toppers induced a continuous and more rapid decline in core body temperature compared to low rebound [LR] mattress toppers during the initial phase of nocturnal sleep in young healthy volunteers. HR toppers are characterized by their supportive feel and high breathability whereas LR toppers are pressure-absorbing. In the current study, we evaluated effects of HR mattress toppers on objectively-(actigraphy) and subjectively-(questionnaires) evaluated sleep, vigilance (psychomotor vigilance test), and athletic performance (40-m sprint time, long jump distance, and star drill time) in youth male athletes age 10–19, in two sessions: fifty-one subjects in 2013 (study I) and 23 subjects in 2014 (study II). Sleeping on HR mattress toppers for four to six weeks improved some athletic performance measures compared to sleeping on LR or sleeping directly on spring mattresses without a topper. Statistically significant improve...

Background: Only a few patients with strokes following suicide attempt (SFSA) are described in th... more Background: Only a few patients with strokes following suicide attempt (SFSA) are described in the literature and dissection of cervical arteries is the best-known mechanism. We aimed to determine the frequency, clinical presentation, mechanisms and outcomes of such patients by systematic observation in a single academic institution.Method: We retrospectively identified in our acute ischemic stroke registry all SFSA over 11 years. A thorough work-up was performed to establish the stroke mechanism. We also searched all published SFSA in the world literature for further analysis of demographics, comorbidities and long-term outcome. Results: Work-up showed multiple stroke mechanisms as well as multiple psychiatric. After adding 7 already published SFSA and comparing all SFSA with our stroke registry, SFSA were younger, had similar stroke severity, higher early mortality, and similar long-term functional outcome.Conclusions: SFSA is rare, affects younger patients and may be missed witho...

The Japanese Journal of Rehabilitation Medicine, 2018

Journal of Affective Disorders, 2017

Sleep complaints are associated with reduced left prefrontal activation during a verbal fluency t... more Sleep complaints are associated with reduced left prefrontal activation during a verbal fluency task in patients with major depression: A multi-channel near-infrared spectroscopy s t u d y ,

Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine, Jan 29, 2016

Delayed encephalopathy (DE) after acute carbon monoxide poisoning causes persistent or delayed co... more Delayed encephalopathy (DE) after acute carbon monoxide poisoning causes persistent or delayed cognitive deficits. Although DE affects not only the cerebral white matter and globus pallidus but also the cortex and thalamus, whether these brain lesions alter sleep along with clinical manifestations of DE remains unknown. A 46-year-old man with DE underwent repetitive hyperbaric oxygen therapy. The patient was evaluated by not only neuropsychological and neuroimaging testing but polysomnography (PSG) over the clinical course. Neurological symptoms improved markedly; however, profound frontal cognitive deficits continued. The PSG revealed prolonged absence and delayed recovery of sleep spindles across recordings. Alterations in spindle oscillations in DE could provide further insight into sleep regulatory networks.

Japanese journal of leprosy, 2007

Neurology Psychiatry and Brain Research

Psychogeriatrics, 2012

Here, we report a case of rapid eye movement sleep behavioural disorder in an elderly patient wit... more Here, we report a case of rapid eye movement sleep behavioural disorder in an elderly patient with dementia with Lewy bodies. Pretreatment polysomnography revealed atonia during rapid eye movement sleep, absence of sleep spindles and loss of slow-wave sleep. Administration of donepezil, an acetylcholinesterase inhibitor, markedly improved delusional symptoms and cognitive function. Pretreatment polysomnography performed after donepezil administration revealed a considerable number of sleep spindles. The effects of cholinergic modulation induced by donepezil seemed to cause remarkable improvement in mental status, incorporating associated with sleep spindles generated by the thalamocortical circuit involved in this patient.

International Clinical Psychopharmacology, 2004

We report that perospirone may have had positive effects on the obesity of three patients with sc... more We report that perospirone may have had positive effects on the obesity of three patients with schizophrenia and on the fasting blood sugar (FBS) and HbA1C of two of them who had type 2 diabetes mellitus.

Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society, 2014

To compare the properties of sleep spindles between healthy subjects and medicated patients with ... more To compare the properties of sleep spindles between healthy subjects and medicated patients with major depressive episode, including frequency range, spectra power, and spatial distribution of spindle power. Continuous 16-channel EEG was used to record nocturnal sleep in healthy control subjects and medicated depressive patients. Recordings were analyzed for changes in EEG power spectra and power topography. Additionally, we graphically demonstrated the pattern of spatial distribution of each type of sleep spindle, divided into fast (12.5-14 Hz) and slow spindles (11-12.5 Hz). Sleep EEG records of depressive subjects exhibited a significantly higher amplitude of slow spindles in the prefrontal region, compared with the healthy controls (P < 0.01). Fast spindles were dominant in the centroparietal region in both depressive patients and the control group. Enhanced slow spindles in the prefrontal region were observed in the medicated depressive patients and not in the healthy contro...

Neuropsychiatric Disease and Treatment

Background: The development of attention-deficit/hyperactivity disorder (ADHD) and autism spectru... more Background: The development of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASDs) has various influences on physical abilities. Identification of specific physical abilities of people with ADHD/ASDs as biomarkers for diagnosing these conditions is necessary. Therefore, in the present review, we aimed firstly to extract the difference in physical abilities of people with ADHD or ASDs compared to those of normal individuals. Secondly, we aimed to extract the specific physical ability characteristics for identifying potential diagnostic biomarkers in people with ADHD/ASDs. Methods: A systematic literature review was performed. The databases were searched for relevant articles on motor function deficits and characteristics of ADHD or ASD. Results: Forty-one cross-sectional studies and three randomized controlled trials were identified, comprising 33 studies of ADHD, 10 studies of ASDs, and 1 study of both ADHD and ASDs. The quality of studies varied. Three types of physical activities/exercises were identified, including coordinated movement, resistance-type sports, and aerobic-type sports. People with ADHD/ASDs generally exhibited poorer physical abilities for all types of activities, possibly because of low levels of physical activity. Specifically, we found temporal discoordination of movement in ADHD and integration or synchronization of separate movements in ASDs. Conclusion: Specific deficits in physical ability may be attributed to ADHD/ASDs. However, there is not enough research on the physical abilities of people with ADHD and ASDs to clarify the specific deficits. Investigation of specific motor functions that characterize ADHD/ASDs should be facilitated.

Nature and Science of Sleep, 2016

Evidence has accumulated, which indicates that, in healthy individuals, sleep enhances procedural... more Evidence has accumulated, which indicates that, in healthy individuals, sleep enhances procedural memory consolidation, and that sleep spindle activity modulates this process. However, whether sleep-dependent procedural memory consolidation occurs in patients medicated for major depressive disorder remains unclear, as are the pharmacological and physiological mechanisms that underlie this process. Methods: Healthy control participants (n=17) and patients medicated for major depressive disorder (n=11) were recruited and subjected to a finger-tapping motor sequence test (MST; nondominant hand) paradigm to compare the averaged scores of different learning phases (presleep, postsleep, and overnight improvement). Participants' brain activity was recorded during sleep with 16 electroencephalography channels (between MSTs). Sleep scoring and frequency analyses were performed on the electroencephalography data. Additionally, we evaluated sleep spindle activity, which divided the spindles into fast-frequency spindle activity (12.5-16 Hz) and slow-frequency spindle activity (10.5-12.5 Hz). Result: Sleep-dependent motor memory consolidation in patients with depression was impaired in comparison with that in control participants. In patients with depression, age correlated negatively with overnight improvement. The duration of slow-wave sleep correlated with the magnitude of motor memory consolidation in patients with depression, but not in healthy controls. Slow-frequency spindle activity was associated with reduction in the magnitude of motor memory consolidation in both groups. Conclusion: Because the changes in slow-frequency spindle activity affected the thalamocortical network dysfunction in patients medicated for depression, dysregulated spindle generation may impair sleep-dependent memory consolidation. Our findings may help to elucidate the cognitive deficits that occur in patients with major depression both in the waking state and during sleep.

Sports Medicine International Open, 2021

This study explored the effect of long naps on handball-related performance and assessed the role... more This study explored the effect of long naps on handball-related performance and assessed the role of the cardiac autonomic nervous system in this process. Eleven male collegiate handball players performed a repeated sequential trial consisting of a 20-m consecutive turnaround run, 10-m run with a load, and shooting the ball into a target. Participants were allocated randomly and sequentially to have a short (20 minutes) nap, long (60 minutes) nap, or no nap. The Pittsburgh Sleep Quality Index was used to assess regular sleep quality. Subjective sleepiness before and after napping was measured using the Karolinska Sleepiness Scale. Heart rate variability was recorded to assess cardiac autonomic nervous function during napping. The Pittsburgh Sleep Quality Index score was correlated with shot accuracy only after long naps (ρ=0.636, r=0.048). A negative correlation was observed between the root mean square of successive differences and average load run time (ρ=−0.929, p<0.001). Long...

Although ample evidence has demonstrated that daytime napping is beneficial for health and cognit... more Although ample evidence has demonstrated that daytime napping is beneficial for health and cognitive performance, bedding for napping has not yet been scientifically investigated. In this study, we assessed the effect of a bean bag chair (BC), which would automatically adjust according to body shape and size, on daytime napping and physiological parameters related to sleep, such as electroencephalogram (EEG), electromyogram (EMG), and heart rate variability (HRV). Fourteen healthy participants were enrolled within the context of a randomized, single-blind, crossover study to evaluate the effects of a BC in comparison with those of a urethane chair manufactured to have a similar shape (UR). EEG analyses revealed no significant differences in sleep architecture or frequency components; however, a significant decrease was found in EMG recordings in the trapezius muscle, which represents the neck region (p = 0.024). Additionally, a significant main effect of bedding in the LF/RF ratio (...

Journal of Medical and Biological Engineering, 2020

When examining cerebral activity, it is important to decrease a subject’s fatigue with an appropr... more When examining cerebral activity, it is important to decrease a subject’s fatigue with an appropriate task design that also maintains data quality. This study evaluated how well devices designed to reduce fatigue would affect functional near-infrared spectroscopy (fNIRS) data. A WOT-100 10-channel wearable fNIRS system was used to study the prefrontal areas of thirteen healthy volunteers. The stimulation task was a consistent incongruent Stroop test, but with two variations. First, the subjects’ answers could be delivered either by vocalization or keyboard output. Second was whether or not there was an offset such as simple finger movements or vocalization during control periods. Four sessions using both variations were performed. The relative changes of fNIRS data during the stimulation periods were used as a marker for cerebral activity. There was only a significant difference in two channels (Channel 3: p = 0.040, Channel 9: p = 0.022) when voice output was used. The result might have been due to voice output being generated from the temporal area, near the prefrontal area. We found that the omission of offset with keyboard output might be possible as there was only a small effect, but offset with voice output is necessary.

Indian Journal of Sleep Medicine, 2010

The Journal of ECT, 2017

Background: The effects of repetitive transcranial magnetic stimulation (rTMS) on physical activi... more Background: The effects of repetitive transcranial magnetic stimulation (rTMS) on physical activity and sleep patterns in individuals with major depressive disorder (MDD) remain unclear. Method: We examined the effects of rTMS treatment on the rest-activity cycle and sleep disturbances in MDD. In this open-label pilot study, 14 patients with medication-resistant MDD underwent 10 rTMS sessions over the bilateral dorsolateral prefrontal cortex. In addition to Hamilton Depression Rating Scale and Pittsburgh Sleep Quality Index scores, waist actigraphy was used to evaluate alterations in the rest-activity cycle over the course of rTMS treatments. Actigraphic data were evaluated at baseline and in the first (rTMS sessions 1-3), second (rTMS sessions 4-7), and third (rTMS sessions 8-10) sections. Results: Although Hamilton Depression Rating Scale and Pittsburgh Sleep Quality Index scores were significantly improved by rTMS, sleep variables assessed by actigraphy did not show significant changes. However, post hoc tests indicated a significant increase in mean steps per day between the baseline and first section time points (P = 0.014; t 13 = −2.316). Conclusions: Our data indicated that a daytime physical activity response to rTMS occurred in early sessions, whereas subjective symptom improvements were consistent across all sessions. Future double-blind placebo-controlled studies assessing the effects of rTMS on the restactivity cycle and sleep disturbances in MDD are warranted.