Shuntaro Itagaki

Event-related potentials in patients with adult attention-deficit/hyperactivity disorder versus schizophrenia

Event-related potentials (ERPs) such as Nd, N2b, and P300 in an attentional task and an auditory oddball task were compared among 54 adult AD/HD patients, 43 schizophrenic patients (SZ), and 40 healthy age-matched volunteers (HC). It is known that Nd, N2b, and P300 reflect selective attention, voluntary attention, and cognitive context updating respectively. The peak amplitude of P300 was significantly lower in the adult AD/HD and SZ groups than in the HC group. The peak latencies of late Nd, N2b, and P300 were significantly longer in the SZ group than in the HC and adult AD/HD groups. Thus, attenuated amplitude and prolonged latency of various ERP components in the SZ group suggest the possibility of impairment of basic mechanisms underlying cognitive processing. Unlike the SZ group, the adult AD/HD group exhibited reduced amplitude of P300 but not prolonged latency. These findings suggest the existence of a different type of cognitive dysfunction in the adult AD/HD group, which might be closely related to attentional function.

Effective surgical intervention for schizophrenia-like symptoms and low event-related potentials caused by arachnoid cyst.

quine 200 mg/day and had remission of symptoms. She had had one major depressive episode at the age of 43 and a manic episode at 51, which had subsided under psychotropic treatment within 1 month. She was admitted to our psychiatric ward due to persecutory delusion, auditory and visual hallucination, and labile mood for 1 week. As the patient had normal serological data, no systemic lupus signs, and no abnormality on brain computed tomography (CT), both the rheumatologist and psychiatrist favored the diagnosis of bipolar I disorder with psychotic features. To control her psychotic symptoms, we first prescribed aripiprazole 15 mg/day. However, her visual and tactile hallucinations were aggravated. She often witnessed and felt water dripping on her face from the dry ceiling. Two weeks later, we switched to amisulpride 800 mg/day but there was still no improvement. Meanwhile, another major depressive episode developed, which did not respond to lamotrigine 150 mg/day and bupropion 300 mg/day augmentation. The rheumatologist still favored primary psychosis because the autoimmune profiles (anticardiolipin antibodies [IgG and IgM], C3, C4 complements, antinuclear antibody, anti-Ro, anti-La, D-D dimmer) were still within normal limits. Nevertheless, her erythrocyte sedimentation rate (ESR) was 62 mm/h. On the third rheumatologic consultation, brain magnetic resonance imaging (MRI) revealed a 0.8-cm old infarction in the left thalamus and old leukoaraiosis in periventricular white matter. Tc-ECD brain single-photon emission computed tomography (SPECT) showed bilateral ventricle dilatation, and moderate to severe hypoperfusion in bilateral frontal and parietal cerebrum. The diagnosis was modified to NPSLE. On the 90th day of admission, she was transferred to the rheumatologic ward for immunosuppressant therapy. After a 3-day course of cyclophosphamide pulse therapy, she was discharged with dramatic improvement. Although her lupus activity seemed in the remitted phase, NPSLE was most likely due to persistently vivid tactile and visual hallucination, the changeable and treatment-refractory course of psychosis and depression, abnormally high level of ESR as well as brain hypoperfusion on SPECT. The dramatic improvement under a 3-day course of cyclophosphamide pulse therapy supported our rationale. The moderate-tosevere hypoperfusion in bilateral frontal and parietal lobes could explain her psychotic and depressive symptoms. Patchy hypoperfusion in the parietal lobes and frontal lobes occurs in up to 80% and 65%, respectively, in SPECT in patients with NPSLE. The infarct and periventricular white matter changes are also common findings. Though her presentations did not fulfill the usual diagnostic criteria of SLE, the evidences strongly suggested NPSLE. Although there is still no single neurodiagnostic tool proven to be definitive in diagnosing NPSLE, we suggest that, for a patient in the remitted phase of SLE showing psychosis, the brain MRI and SPECT could be beneficial in making the differential diagnosis and further management.

Exercise Habits Are Important for the Mental Health of Children in Fukushima After the Fukushima Daiichi Disaster: The Fukushima Health Management Survey

After the Great East Japan Earthquake and the subsequent nuclear reactor accident, the outdoor activities of children greatly decreased. We investigated adverse effects on the exercise habits and mental health of children after the disaster. The target subjects were children aged 6 to 15 years living inside the government-designated evacuation zone as of March 11, 2011 (n = 29  585). The subjects’ parents/guardians completed the Strengths and Difficulties Questionnaire (SDQ) and exercise habit data were obtained from the 2011 Fukushima Health Management Survey. A total of 18  745 valid responses were returned. We excluded questionnaires with incomplete answers leaving 10  824 responses for the final analysis. SDQ scores ≥16 indicated high risk of mental health. Children in the evacuation zone who did not get regular exercise had a higher risk of mental problems as evaluated by SDQ (multivariate-adjusted prevalence ratio [PR] = 1.49; 95% CI 1.38-1.62). When stratified by sex, age, place of residence, treatment for illnesses and experienced the nuclear reactor accident the associations were essentially the same. Regular exercise is important for maintaining children’s mental health after a disaster. This is the first large-scale report to examine the impact of outdoor exercise limitations among children in a nuclear accident.

Temporal integration of segmented-speech sounds probed with mismatch negativity.

Deviant sounds occurring in a sequence of standard sounds, in the absence of attention, elicit an event-related potential known as mismatch negativity (MMN). Standard sounds are encoded in auditory sensory memory trace and processed as a single unit within 160–170 ms, where each unitary event stored is closely related to the temporal window of integration. The temporal window of integration of pure tone sound has already been reported. However, there are no reported correlations between segmented-speech sounds and a temporal unit. It is well known that pure tone sounds are predominantly recognized in the right hemisphere, whereas speech sounds are recognized in the left hemisphere. The aim of this study was to examine whether segmented-speech sounds were processed as a temporal unit like pure tone sounds and whether there were differences between right and left ear stimuli. Twenty-five right-handed healthy Japanese men participated in this study. Stimuli consisted of the vowel /a/ spoken by a Japanese female and the stimuli sequences were randomized from short standard sounds and three types of long deviant sounds. The stimuli were presented to both ears separately. All bilateral stimuli induced definite MMN with similar peak latencies. The MMN amplitude gradually enhanced from the short to the long duration deviant. There were no differences in MMN between the right and the left ear stimuli. These findings perhaps show that bilateral deviant segmented-speech sounds were processed equally as a temporal unit.

Only a stimulus onset might initiate the temporal window of integration

The acoustic brain has the ability to detect the deviant sounds in the series of homogeneous sounds. The mismatch negativity (MMN) is considered to reflect this ability. Various types of deviations including the omission of sound can elicit MMN. MMN is generated by the comparison process between sound change and the memory trace of the preceding sounds stored in sensory memory. When the trace of sound is formed in sensory memory, the mechanism termed the temporal window of integration (TWI) which integrates the closely presented sounds into single units is activated. MMN to omission has provided the evidence for the presence of TWI mechanism. MMNs were elicited by the omitted tones only when SOAs were shorter than 160 ms. It suggests a temporal correspondence between the duration of the neural sound representations in sensory memory and the TWI of 160–170 ms. However, nobody knows whether TWI is initiated by the stimulus onset or not. Therefore, we tried to clarify what initiates the TWI as reflected by MMN. We employed four types of stimulus pairs of the deviants and standards which were different in duration. Finally, we found that the onset of stimulus initiated the TWI, and the TWI did not slide with the stimulus.

Trajectories of Emotional Symptoms and Peer Relationship Problems in Children after Nuclear Disaster: Evidence from the Fukushima Health Management Survey

The Fukushima Daiichi Nuclear Power Plant accident, which occurred in March 2011, is having long-term effects on children. We planned this study to describe the trajectories of emotional symptoms and peer relationship problems in children and to examine potential risks and protective factors over the 35 months following the accident. The sample was 11,791 children in the first to sixth elementary grades. We identified four patterns for emotional symptoms and three patterns for peer relationship problems, using group-based trajectory modelling. For emotional symptoms, female gender, experience of tsunami and nuclear plant accident, out-of-prefecture evacuees, and insufficient physical activity were associated with the very severe trajectory. In contrast, for peer relationship problems, male gender, experience of nuclear plant accident, and insufficient physical activity were associated with the very severe trajectory. Different factors might be related to the very severe trajectories of emotional symptoms and peer relationship problems.

The Relationship between Sleep Time and Mental Health Problems According to the Strengths and Difficulties Questionnaire in Children after an Earthquake Disaster: The Fukushima Health Management Survey

A cross-sectional study was performed on the adverse effects of sleep time on the mental health of children after the Great East Japan Earthquake and subsequent nuclear reactor accident in March 2011. The target participants were children aged 4–15 years living inside the government-designated evacuation zone as of 11 March 2011 (n = 29,585). The participants’ parents/guardians completed the Strengths and Difficulties Questionnaire (SDQ) and sleep time data were obtained from the 2011 Fukushima Health Management Survey. A total of 18,745 valid responses were returned. We excluded questionnaires with incomplete answers leaving 13,272 responses for the final analysis. First, we divided the children into three age groups for analysis. Second, we divided each age group into four or five groups based on sleep time per day. We used SDQ scores ≥16 to indicate a high risk of mental health problems. In the 4–6-year-old group, those with a sleep time of <9 h had a higher risk. In the 7–12-year-old group, those with ≥10 h of sleep time had a higher risk. In the 13–15-year-old group, those with ≥9 h of sleep time had a higher risk. Shorter sleep time was associated with a higher risk of mental health in 4–6-year-olds. On the other hand, oversleeping was associated with a high risk of mental health in 7–15-year-olds.

The efficacy of antipsychotics for prolonged delirium with renal dysfunction

Aim Delirium is commonly encountered in daily clinical practice. To identify predictors influencing outcomes, we retrospectively examined the characteristics of inpatients with delirium who required psychiatric medication during hospitalization. Methods We extracted all new inpatients (n=523) consulted for psychiatric symptoms at Fukushima Medical University Hospital between October 2011 and September 2013. We selected 203 inpatients with delirium diagnosed by psychiatrists. We analyzed data from 177 inpatients with delirium who received psychiatric medication. We defined an “early improvement group” in which delirium resolved in ≤3 days after starting psychiatric medication, and a “prolonged group” with delirium lasting for >3 days. Among the 83 inpatients with renal dysfunction (estimated glomerular filtration rate <60 mL/min/1.73 m2), we defined an “early improvement group with renal dysfunction” in which delirium resolved in ≤3 days after starting psychiatric medication and a “prolonged group with renal dysfunction” with delirium lasting for >3 days. We then examined differences between groups for different categorical variables. Results Dose of antipsychotic medication at end point was significantly lower in the prolonged group with renal dysfunction than in the early improvement group with renal dysfunction. Conclusion The results suggest that maintaining a sufficient dose of antipsychotics from an early stage may prevent prolongation of delirium even in inpatients with renal dysfunction.

Dynamic changes in near-infrared spectroscopy (NIRS) findings in first-episode schizophrenia: a case report

The clinical course of schizophrenia is characterized by recurrence and chronicity and has a large burden on society.　Nevertheless, diagnosis of schizophrenia is based only on distinctive symptoms and the disease course.　Near-infrared spectroscopy (NIRS) is a useful method for measuring changes in the hemoglobin concentration in the cortical surface area and reflects brain function.　We measured NIRS four times during the clinical course in a patient with first-episode schizophrenia.A 17-year-old woman admitted to our hospital because of hallucinations, delusions and appetite loss. After treatment with low-dose antipsychotics, NIRS findings showed a prompt increase in the cerebral blood volume in the frontal region.　On the basis of the clinical course of this patient, we introduce a new point of view, namely, that NIRS findings may be useful as a state marker that indicates the severity of schizophrenia in some cases.

S12-5. The history of mismatch negativity researches in dementia

The mismatch negativity (MMN) component of the event-related potentials reflects the automatic detection mechanism of sound change. MMN is elicited by a neuronal mismatch process between deviant (infrequent) auditory input and the sensory memory trace of standard (frequent) stimuli. Dementia is one of the memory disorders, and some studies have suggested that MMN reflecting in the memory trace relevance to dementia. Pekkonen et al. (1994, 2000) and Kolbjorn et al. (2010) investigated whether MMN responses were elicited in patients with Alzheimer disease. They found MMN was fairly unaffected in patients with Alzheimer disease at short inter-stimulus intervals (ISIs), whereas MMN was reduced at long ISIs in the same patients. The prolonged ISIs did not affect the deviation process but the developing process of a memory trace. We therefore suggested that investigation of a memory trace as reflected by the MMN response which is elicited by ISIs change reflects the memory function in a patient with dementia.