慢性期統合失調症患者における、聴性定常反応を指標とした高周波数及び低周波数γ帯域同期性の検討

1. Introduction / 2. Methods / 3. Results / 4. Discussion / References / Figure legendsSubmitted by 真弓 小柳 ([email protected]) on 2012-04-20T01:08:49Z No. of bitstreams: 8 med2468.pdf: 145456 bytes, checksum: d2e1c81db81cabf4244f683e3101c65a (MD5) med2468_abstract.pdf: 242533 bytes, checksum: 0952c914c85e12858002f759abdb9b15 (MD5) med2468_Figure1.pdf: 82882 bytes, checksum: fc894e482f9850bff8b135366065f0db (MD5) med2468_Figure2.pdf: 285105 bytes, checksum: 9dc61ce903eca79bef050cf1459c0476 (MD5) med2468_Figure3.pdf: 320928 bytes, checksum: 46f762fa08dc2a56d2a77e23b050e077 (MD5) med2468_Figure4.pdf: 125292 bytes, checksum: bd3f6add8a10bc96f7928c42b8dab0d2 (MD5) med2468_Figure5.pdf: 71127 bytes, checksum: 7cce7af7ab56c1f1adf0df7130f590d5 (MD5) med2468_Table.pdf: 65412 bytes, checksum: a5c0b455e98ad801893c58d7605ff1a8 (MD5)Made available in DSpace on 2012-04-20T01:08:49Z (GMT). No. of bitstreams: 8 med2468.pdf: 145456 bytes, checksum: d2e1c81db81cabf4244f683e3101c65a (MD5) med2468_abstract.pdf: 242533 bytes, checksum: 0952c914c85e12858002f759abdb9b15 (MD5) med2468_Figure1.pdf: 82882 bytes, checksum: fc894e482f9850bff8b135366065f0db (MD5) med2468_Figure2.pdf: 285105 bytes, checksum: 9dc61ce903eca79bef050cf1459c0476 (MD5) med2468_Figure3.pdf: 320928 bytes, checksum: 46f762fa08dc2a56d2a77e23b050e077 (MD5) med2468_Figure4.pdf: 125292 bytes, checksum: bd3f6add8a10bc96f7928c42b8dab0d2 (MD5) med2468_Figure5.pdf: 71127 bytes, checksum: 7cce7af7ab56c1f1adf0df7130f590d5 (MD5) med2468_Table.pdf: 65412 bytes, checksum: a5c0b455e98ad801893c58d7605ff1a8 (MD5) Previous issue date: 2012-03-27医学系学府_医学統合失調症では、認知や行動の機能障害の基盤として、神経回路の異常が存在することが示唆されている。聴性定常反応the auditory steady state response (ASSR)は聴覚処理の神経回路機能の指標の一つとなり得ると考えられている。さらに近年では、高周波数γ帯域(> 60Hz) oscillationsに関する研究に関心が持たれている。今回の研究では、全頭型の306チャンネル脳磁計を用い、低周波数、高周波数帯域のASSRを測定した。対象は、17名の統合失調症患者と22名の健常対照者である。両耳に20、30、40、80Hzの頻度でクリック音を提示した。ASSRの平均パワー、平均位相同期性phase-locking factor、電流双極子（ダイポール）モーメント、ダイポールの位置を算出した。また、統合失調症患者の症状とASSRの関連について調べた。主な結果は以下の通りであった。１）40 Hzと80 Hzにおいて、統合失調症患者では両側性にパワーとダイポールモーメントが減少していた、２）健常対照者で認められる40 Hz刺激でのASSR パワーとphase-locking factorの右＞左というパターンは統合失調症患者で失われていた、３）統合失調症では、幻聴の重症度と80Hz刺激での左半球におけるASSRパワーは負の相関を示した。今回の研究で高周波数、低周波数γ帯域の異常が明らかになった。これは統合失調症の神経回路異常を示している可能性が高い。Schizophrenia has been conceptualized by dysfunctional cognition and behavior related to abnormalities in neural circuitry. The functioning of the neural circuitry can be assessed using the auditory steady state response (ASSR). Moreover, in recent years, research on high (>60 Hz) gamma band oscillations has become of increasing interest. The current study used whole-head, 306-channel magnetoencephalography (MEG) and investigated low and high gamma band oscillations with the ASSR. The subjects comprised 17 patients with schizophrenia and 22 controls. The current study investigated the MEG-ASSR elicited by click trains of 20-, 30-, 40- and 80-Hz frequencies, and symptom-ASSR associations in patients with schizophrenia. The mean power, phase-locking factor, dipole moments and source locations of the ASSR were estimated. The main findings were : (1) patients with schizophrenia showed bilaterally reduced ASSR power and dipole moments specific to the 40-Hz and 80-Hz frequencies ; (2) patients with schizophrenia showed less right-greater-than-left 40-Hz ASSR power and phase-locking factor compared with healthy subjects, indicating that schizophrenics may be characterized by an abnormal asymmetry of the 40-Hz ASSR ; (3) increased severity of global hallucinatory experiences was significantly associated with smaller left 80-Hz MEG-ASSR in patients with schizophrenia. The current study highlights the high and low frequency gamma abnormalities and provides clear evidence that schizophrenia is characterized by abnormalities in neural circuitry

Anthropometrics, Lifestyle and BP

Background : High blood pressure (BP) is a healthcare problem in young persons. There are racial differences in anthropometrics, dietary habit and lifestyle relating to BP. Therefore, this study investigated the relationship between anthropometrics, lifestyle and BP obtained in the Japanese university students. Materials and Methods : Participants were recruited in annual health screening including questionnaire, measurements of BP and anthropometrics calculating body mass index (BMI). Totally, 14,280 students (10,273 males and 4,007 females) were eligible. Multiple regression analyses were applied to predict contributors to high BP. Results : BMI was the most powerful contributor to high BP in many subgroups divided by gender and graduation (p < 0.001). In lifestyle, contribution of lack of exercise to high BPs was observed in the undergraduates. Smoking drinking and breakfast skipping had no significant impact on high BP. However, smoking and drinking permeated and exercise habit declined after graduation. Prevalence of obesity (BMI ≥ 25 kg / m2) and hypertension ( ≥ 140 / 90 mmHg) increased in subgroups with advanced age (p < 0.001). Conclusion: BMI was found to be the most powerful contributor to high BPs. Health literacy to modify lifestyle is important to prevent hypertension for university students who are exposed to social trends of unhealthy lifestyle

Gamma Band Neural Synchronization Deficits for Auditory Steady State Responses in Bipolar Disorder Patients

Periodic auditory click stimulation has been reported to elicit an auditory steady state response (ASSR). The ASSR has been suggested to reflect the efficiency of γ-amino butyric acid (GABA) inhibitory interneuronal activity. Although a potential role for GABAergic dysfunction has been previously proposed, the role of neural synchronization in the ASSR in people with bipolar disorder (BD) has received little attention. In the current study, we investigated ASSRs to 20 Hz, 30 Hz, 40 Hz and 80 Hz click trains in BD patients. A total of 14 (4 males) BD patients and 25 (10 males) healthy controls participated in this study. ASSRs were obtained using whole-head 306-channel magnetoencephalography to calculate, ASSR power values and phase locking factors (PLF). BD patients exhibited significantly reduced mean ASSR power and PLF values bilaterally at frequencies of 30, 40, and 80 Hz (p<0.05 for these frequencies). At 20 Hz, bipolar patients showed no significant reduction in mean ASSR power and PLF values. There was a significant negative correlation between 80 Hz-ASSR-power values obtained from the right hemisphere and scores on the Hamilton Depression Rating Scale (rho = −0.86, p = 0.0003). The current study showed reduced low and high gamma band ASSR power and PLF bilaterally with no significant beta band ASSR reduction in BD patients. BD patients are characterized by deficits in gamma band oscillations, which may be associated with GABA inhibitory interneuronal activity dysfunction

Layout of the measured channels.

<p>The MEG signals were acquired using a whole-head, 306-channel sensor array comprised of 102 identical triple-sensor elements. Each sensor consisted of two orthogonal planar-type gradiometers and one magnetometer. We used 11 sensors (a 22-channel orthogonal gradiometer) around the location that elicited the strongest response in each hemisphere. Circled squares indicate the sensors used for analysis.</p

Dipole locations of the ASSR.

<p>Data are given as mean ± SD. HC: healthy controls, BD: patients with bipolar disorder.</p><p>The zero point was the mid-point of the line connecting the bilateral preauricular points. The x-axis was the line from the left to the right with positive values toward the right, the y-axis was the postero-anterior line with positive values presented anteriorly, and the z-axis was the ventro-dorsal line with positive values located dorsally.</p

Mean ASSR-power.

<p>Data are given as mean ± SD.</p><p>ASSR: auditory steady state response, HC: healthy controls,</p><p>BD: patients with bipolar disorder.</p

Mean ASSR PLF.

<p>Data are given as mean ± SD.</p><p>ASSR: auditory steady state response, PLF: phase locking factor,</p><p>HC: healthy controls, BD: patients with bipolar disorder.</p

Group averaged time-frequency maps of ASSR-PLF for each hemisphere.

<p>The color scales signify ASSR-PLF value. HC, healthy controls; BD, patients with bipolar disorder.</p

Demographic and Clinical Characteristics of Participants.

<p>Values are mean ± SD unless otherwise noted. HC: healthy controls, BD: patients with bipolar disorder,</p><p>SES = socioeconomic status, YMRS = Young Mania Rating Scale, SIGH-D = Structured Interview Guide for the Hamilton Depression Rating Scale.</p><p>Patients with BD were administered the following medications : N = 2 lithium & valproate; N = 1 lithium, quetiapine & zotepine; N = 1 lithium & quetiapine; N = 1 quetiapine, amoxapine & paroxetine; N = 1 valproate, amoxapine, trazodone & paroxetine; N = 1 valproate & quetiapine, N = 1 quetiapine & paroxetine; N = 1 lithium, valproate, quetiapine & amitriptyline; N = 1 valproate & trazodone; N = 1 lithium, valproate, olanzapine & risperidone; N = 1 valproate & quetiapine; N = 1 lithium, valproate & quetiapine; N = 1 lithium, quetiapine & levomepromazine.</p