Usefulness of Prehospital 12-Lead Electrocardiography System in ST-Segment Elevation Myocardial Infarction Patients in Oita　- Comparison Between Urban and Rural Areas, Weekday Daytime and Weekday Nighttime/Holidays.

BACKGROUND: We have reported that a prehospital 12-lead electrocardiography system (P-ECG) contributed to transport of suspected acute coronary syndrome (ACS) patients to appropriate institutes and in this study, we compared its usefulness between urban and rural areas, and between weekday daytime and weekday nighttime/holiday.Methods and Results: Consecutive STEMI patients who underwent successful primary percutaneous coronary intervention after using P-ECG were assigned to the P-ECG group (n=123; 29 female, 70±13 years), and comparable STEMI patients without using P-ECG were assigned to the conventional group (n=117; 33 females, mean age 70±13 years). There was no significant difference in door-to-reperfusion times between the rural and urban cases (70±32 vs. 69±29 min, P=0.73). Door-to-reperfusion times in the urban P-ECG group were shorter than those in the urban conventional group for weekday nighttime/holiday (65±21 vs. 83±32 min, P=0.0005). However, there was no significance different between groups for weekday daytime. First medical contact to reperfusion time (90±22 vs. 105±37 min, P=0.0091) in the urban P-ECG group were significantly shorter than in the urban conventional groups for weekday nighttime/holiday, but were not significantly different between the groups for weekday daytime. CONCLUSIONS: P-ECG is useful even in urban areas, especially for patients who develop STEMI during weekday nighttime or while on a holiday.

Prehospital 12-Lead Electrocardiography System in Oita Assisted Transport of "True" Acute Coronary Syndrome Patients to Optimal Institutes.

BACKGROUND: Mobile cloud electrocardiography (C-ECG) can reduce the door-to-balloon time of acute coronary syndrome (ACS) patients, so we hypothesized it would also assist in transporting ACS-suspected patients to the optimal institutes.Methods and Results: Initially, 10 fire departments in Oita had 10 ambulances equipped with C-ECG. Ambulance crews recorded a 12-lead ECG from the patient at the first point of contact and transmitted them to 18 hospitals (13 institutions (PCII) with 24-h availability for percutaneous coronary intervention (PCI) and 5 regional core hospitals (RCH) without 24-h PCI) for analysis by a cardiologist. During 41 months, 476 ECGs suspected to be ACS were transmitted and analyzed. Of these, 24 ECGs transmitted to PCII were judged as not requiring PCI, and the patients were directly transported to a RCH (PCII-RCH); 35 ECGs sent to a RCH were judged as requiring PCI, and the patients were directly transported to a PCII (RCH-PCII). The prevalence of cardiovascular disease was significantly higher in the RCH-PCII group than in the PCII-RCH group (P<0.01). There was no significant difference in the door-to-balloon time between the RCH-PCII and the group in which the C-ECG was sent to a PCII and the patients were transported directly to PCII (PCII-PCII) (49±14 vs. 59±20 min, P=0.14). CONCLUSIONS: Prehospital 12-lead ECG can assist in transporting ACS-suspect patients to the optimal treatment facility.

Affective temperaments are associated with the white matter microstructure in healthy participants.

OBJECTIVES: Five affective temperaments are regarded as potential precursors of bipolar disorder. These are depressive, cyclothymic, hyperthymic, irritable, and anxious temperaments. However, the neural substrates underlying these temperaments have not been identified. The aim of this study was to determine whether these temperaments are associated with specific neural substrates related to the brain white matter integrity in healthy participants. METHODS: We conducted a cross-sectional neuroimaging study of 71 healthy participants (38 males and 33 females) with affective temperaments. All participants screened for past and present psychiatric disorders. The scores of the five affective temperaments were measured by the temperament scale of Memphis, Pisa, Paris, and San Diego-autoquestionnaire. We analyzed the association between the fractional anisotropy (FA) and mean diffusivity (MD) of the brain white matter and these affective temperaments using tract-based spatial statistics (TBSS). RESULTS: The cyclothymic temperament score had a significant positive association with the FA and a significant negative association with the MD in the white matter in the right frontal part of brain. The hyperthymic temperament score was negatively associated with the MD in a wide area of the brain white matter. The anxious temperament score was positively associated with the FA in the bilateral frontal, temporal, and parietal regions of the brain white matter. The depressive and irritable temperament scores were not associated with either the FA or the MD. CONCLUSION: The present findings suggest that cyclothymic, hyperthymic, and anxious temperaments are associated with brain white matter integrity in healthy participants.

Quantitative GABA magnetic resonance spectroscopy as a measure of motor learning function in the motor cortex after subarachnoid hemorrhage.

The neural mechanisms underlying gross and fine motor dysfunction after subarachnoid hemorrhage (SAH) remain unknown. The γ-aminobutyric acid (GABA) deficit hypothesis proposes that reduced neuronal GABA concentrations and the subsequent lack of GABA-mediated inhibition cause motor impairment after SAH. This study aimed to explore the correlation between GABA levels and a behavioral measure of motor performance in patients with SAH. Motor cortical GABA levels were assessed in 40 patients with SAH and 10 age-matched healthy controls using proton magnetic resonance spectroscopy. The GABA and N-acetylasparate (NAA) ratio was measured in the normal gray matter within the primary motor cortex. The relationship between GABA concentration and hand-motor performance was also evaluated. Results showed significantly lower GABA levels in patients with SAH's left motor cortex than in controls (GABA/NAA ratio: 0.282 ± 0.085 vs. 0.341 ± 0.031, respectively; p = 0.041). Reaction times (RTs), a behavioral measure of motor performance potentially dependent on GABAergic synaptic transmission, were significantly longer in patients than in controls (936.8 ± 303.8 vs. 440.2 ± 67.3 ms, respectively; p < 0.001). Moreover, motor cortical GABA levels and RTs exhibited a significant positive linear correlation among patients (r = 0.572, rs = 0.327, p = 0.0001). Therefore, a decrease in GABA levels in the primary motor cortex after SAH may lead to impaired cortical inhibition of neuronal function and indicates that GABA-mediated synaptic transmission in the motor cortex is critical for RT.

Increased volume of the left hippocampal dentate gyrus after 4 weeks of bright light exposure in patients with mood disorders: a randomized controlled study.

Bright light exposure (BL) induces neurogenesis in the rat hippocampal dentate gyrus (DG). We had previously conducted a randomized controlled trial (RCT) in which a 4-week period of BL in healthy participants resulted in increased volume of the left DG-head. This study aimed to investigate the effects of BL on the DG in patients with mood disorders. A 4-week RCT was conducted in which patients with mood disorders were randomly assigned to either a BL group (10,000 lx) or dim light exposure group (DL group; 50 lx). All patients underwent clinical assessment and magnetic resonance imaging at baseline and after the intervention. The study registration number is UMIN000019220. Our final sample included 24 patients (BL group, n = 12; DL group, n = 12). A significant effect of time and group was detected in the volumes of the left DG-head (F (1, 22) = 11.6, partial η2 = 0.35, p = 0.003) and left DG-total (left DG-total = left DG-head + left DG-body; [F (1, 22) = 6.5, partial η2 = 0.23, p = 0.02]). Additionally, the BL group demonstrated a significant increase in the volume of the left DG-head (95% CI: -5.4 to -1.6, d = 1.2, p = 0.002) and left DG-total (95% CI: -6.3 to -1.5, d = 1.06, p = 0.005) as well as a positive correlation between the percentage change in the volume of the left DG-total and the percentage change in the scores of the mood visual analog scale (r = 0.58, p = 0.04). In conclusion, our study results suggest that compared to DL, BL leads to a significantly greater increase in the left DG volume in patients with mood disorders. This increase in the left DG volume may be associated with mood improvement in the patients.

Continuous theta-burst stimulation to the sensorimotor cortex affects contralateral gamma-aminobutyric acid level and resting-state networks.

Continuous theta-burst stimulation (cTBS) is a noninvasive repetitive brain stimulation protocol that suppresses the excitability of the primary motor cortex. It induces cerebral cortical inhibition by increasing inhibitory interneuronal excitability that is associated with increases in gamma-aminobutyric acid (GABA) concentration in the stimulated cortices. cTBS has been applied in the rehabilitation of stroke patients to modulate interhemispheric imbalance. However, the precise mechanisms of cTBS in remote brain areas remain uncertain. We evaluated cTBS-induced GABA level changes in bilateral sensorimotor cortices using GABA-edited magnetic resonance spectroscopy, alternations of motor evoked potentials (MEPs), and resting-state networks (RSNs) using resting-state functional magnetic resonance imaging in 24 healthy right-handed adults (mean age: 34.4 ± 5.0 years). GABA levels in the stimulated left hemisphere significantly increased from baseline (p = 0.013), which was comparable with those of previous reports. GABA levels in the unstimulated right hemisphere showed a trend decrease. cTBS induced a significant decrease in right hand-MEP amplitudes (22.06% ± 43.50%) from baseline (p = 0.026) in accordance with GABA concentrations. However, multiple RSNs, including the default mode and primary motor networks, did not show any obvious differences between pre- and post-stimulus comparisons in the sensorimotor network using the dual regression approach. These results suggest that cTBS simultaneously increases ipsilateral GABA in the stimulated left hemisphere and decreases contralateral GABA in the unstimulated right hemisphere. Neuromodulation following cTBS may be associated with the interhemispheric inhibition because of alterations in GABA levels between the stimulated and unstimulated cortices.

Homocysteine levels are associated with hippocampus volume in type 2 diabetic patients.

BACKGROUND: Elevated total plasma homocysteine (tHcy) levels are associated with cognitive dysfunction, in which changes in the hippocampus plausibly play a pivotal role. We tested the hypothesis that elevated tHcy levels are correlated with hippocampus volume and insulin resistance in nondementia patients with type 2 diabetes. MATERIALS AND METHODS: The study included 43 nondementia patients with type 2 diabetes, who were divided into two groups: a high tHcy group (age: 65 ± 8 years, mean ± standard deviation, n = 16) and a normal tHcy group (64 ± 9 years, n = 27). Hippocampus volume was quantified with a computer-assisted analysis using a magnetic resonance imaging (MRI) voxel-based specific regional analysis system developed for the study of Alzheimer's disease (VSRAD), which yields a Z-score as the end point for the assessment of hippocampal volume. Results The Z-score was higher in the high tHcy group compared to the normal tHcy group (P < 0·0001). The fasting plasma glucose (P < 0·01) and insulin (P < 0·0001) concentrations and the homoeostasis model assessment (HOMA) index (P < 0·0001) were higher in the high tHcy group than in the normal tHcy group. Multiple regression analysis showed that the main factors that influenced tHcy levels may be the Z-score and the HOMA index. CONCLUSIONS: Our results indicate that the elevated levels of tHcy in Japanese nondementia patients with type 2 diabetes are characterised by hippocampal atrophy and insulin resistance and that the Z-score and HOMA index may be the primary factors that influence tHcy levels.

Increase in the left hippocampal dentate gyrus head volume after a 4-week bright light exposure in healthy participants: A randomized controlled study.

INTRODUCTION: Bright light therapy (BLT) has been used for treating seasonal affective disorder, depression and bipolar depression. However, it's precise mechanism remains unclear. Bright light exposure (BL) induces neurogenesis in the adult rat hippocampal dentate gyrus (DG). We hypothesized that BL may induce neurogenesis in the human DG as well. METHOD: A 4-week randomized controlled trial study was conducted, where healthy participants were randomly assigned to a BL group (10,000 lux) or dim light exposure group (DL group; 50 lux). Magnetic resonance imaging was performed at baseline and after 4 weeks. Longitudinal hippocampal subfield segmentation was generated via the FreeSurfer 7.1.1 hippocampal subfields module to evaluate volume of bilateral granule cell and molecular layer of the DG-head and -body. RESULTS: Our final sample size was 20, which consisted of BL group (n = 10) and DL group (n = 10). After age and sex adjustment, significant effects of time and group were detected in the left DG-head volume (p = 0.04). In the BL group, the left DG-head volume significantly increased (p = 0.004), whereas no significant volumetric change was observed in the DL group. CONCLUSIONS: This study revealed that 4-week BL significantly increased left DG-head volume in healthy participants. Thus, neurogenesis might be induced by BL in the human DG, which is a completely new mechanism of BLT.

Perfusion Parameter Obtained on 3-Tesla Magnetic Resonance Imaging and the Ki-67 Labeling Index Predict the Overall Survival of Glioblastoma.

BACKGROUND: Pulsed arterial spin-labeling, diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS) are useful for predicting glioma survival. We performed a comparative review of multiple parameters obtained using these pulse sequences on 3-Tesla magnetic resonance imaging (MRI) including the molecular status and Ki-67 labeling index in newly diagnosed supratentorial glioblastomas. METHODS: A total of 35 patients with glioblastomas underwent pulsed arterial spin-labeling, DTI, and MRS studies using 3-Tesla MRI preoperatively. The isocitrate dehydrogenase (IDH) mutation status, methylguanine-DNA methyltransferase methylation status, and Ki-67 labeling index were calculated from the tumor specimen. Cutoff values were identified by analyzing a receiver operating characteristic curve, and the multivariate survival statistical technique was performed to determine the significant and independent parameters for predicting overall survival. RESULTS: The multivariate Cox analysis showed that the maximum/mean relative cerebral blood flow (rCBF) ratio and the Ki-67 labeling index were significant and independent predictive parameters with a cutoff value of 1.589 for the maximum rCBF ratio, 1.286 for the mean rCBF ratio, and 19% for the Ki-67 labeling index and hazard ratios of 6.132 and 5.119, respectively. The Kaplan-Meier survival curves showed that patients with higher rCBF ratios and Ki-67 labeling indices had a shorter overall survival than others, with median overall survival durations of 479 (95% CI, 370-559) and 1243 (95% CI, 666-NA) days, respectively (P = 0.000167). CONCLUSIONS: Our findings indicate that the preoperative rCBF ratio and Ki-67 labeling index are useful parameters for predicting the overall survival of cerebral glioblastomas.

Abdominal visceral fat accumulation is associated with hippocampus volume in non-dementia patients with type 2 diabetes mellitus.

Obesity is associated with cognitive dysfunction, for which changes in the hippocampus plausibly play a pivotal role. We tested the hypothesis that an elevated level of visceral fat accumulation (VFA) correlates with hippocampus volume and insulin resistance in non-dementia patients with type 2 diabetes. Subjects included 48 non-dementia patients with type 2 diabetes, who were divided into two groups, high VFA group (mean+/-standard deviation: age=65+/-6 years, n=30) and normal VFA group (65+/-5 years, n=18). Hippocampus volume has been quantitated with computer-assisted analysis using a magnetic resonance imaging (MRI) voxel-based specific regional analysis system developed for the study of Alzheimer's disease (VSRAD), which yields a Z-score as the end point for assessment of hippocampal volume. The Z-score was higher in the high VFA group than in the normal VFA group (p<0.0001). The fasting plasma glucose (p<0.05) and insulin concentrations (p<0.0001) and the homeostasis model assessment (HOMA) index (p<0.0001) were higher in the high VFA group than in the normal VFA group. Multiple regression analysis showed that VFA levels were independently predicted by Z-score and HOMA index. Our results indicate that the elevated level of VFA in Japanese non-dementia patients with type 2 diabetes is characterized by increased hippocampus volume and insulin resistance, and that the Z-score and HOMA index are independent predictors of VFA.

Impact of Mobile Cloud Electrocardiography System on Door-to-Balloon Time in Patients With Acute Coronary Syndrome in Oita Prefecture.

Background: The mobile cloud electrocardiography (C-ECG) system is useful for reducing door-to-balloon (DTB) time in patients with acute coronary syndrome (ACS), but few studies have reported the usefulness of the C-ECG system across a wide provincial prefecture, such as Oita, in Japan. Methods and Results: On 17 April 2017, the C-ECG system was integrated into the Oita remote image transmission system, in 10 ambulances of 10 respective fire departments in Oita Prefecture. During 6 months, 162 ECG indicating suspected ACS were transmitted to 18 hospitals using the C-ECG system. Of 162 patients, 17 who received emergency percutaneous coronary intervention (PCI) were assigned to the cloud group (mean age, 71±11 years). The control group consisted of 29 consecutive ACS patients who were transported to Oita University Hospital without using the C-ECG system (mean age, 66±12 years). Another 40 consecutive patients were diagnosed with ACS before transportation to Oita University Hospital, and were assigned to the diagnosed group (mean age, 70±14 years). DTB time (70±26 min vs. 96±24 min, P<0.005) and door-to-catheterization laboratory time (33±20 min vs. 53±22 min, P<0.0001) were shorter in the cloud group than in the control group, respectively. Conclusions: C-ECG system integration in Oita Prefecture was useful to appropriately transfer ACS patients to hospital and to facilitate earlier PCI than in the conventional diagnostic system.

CORRIGENDUM: Impact of Mobile Cloud Electrocardiography System on Door-to-Balloon Time in Patients With Acute Coronary Syndrome in Oita Prefecture.

[This corrects the article DOI: 10.1253/circrep.CR-19-0020.].

Relationship Between the Japanese Version of the Montreal Cognitive Assessment and PET Imaging in Subjects with Mild Cognitive Impairment.

BACKGROUND: The Montreal Cognitive Assessment (MoCA) test has high sensitivity and specificity for detecting mild cognitive impairment or early dementia. How the MoCA score relates to findings of positron emission tomography imaging, however, remains unclear. OBJECTIVE: This prospective study examined the relationship between the Japanese version of the MoCA (MoCA-J) test and brain amyloid deposition or cerebral glucose metabolism among subjects with mild cognitive impairment. METHODS: A total of 125 subjects with mild cognitive impairment underwent the MoCA-J test, and amyloid- and 18F-fluorodeoxyglucose- positron emission tomography. Linear correlation analysis and multiple linear regression analysis were conducted to investigate the relationship between the MoCA-J score and demographic characteristics, amyloid deposition, and cerebral glucose metabolism. Moreover, Statistical Parametric Mapping 8 was used for a voxel-wise regression analysis of the MoCA-J score and cerebral glucose metabolism. RESULTS: The MoCA-J score significantly correlated with age, years of education, and the Mini-Mental State Examination score. After adjusting for age, sex, and education, the MoCA-J score significantly correlated negatively with amyloid retention (ß= -0.174, p= 0.031) and positively with cerebral glucose metabolism (ß= 0.183, p= 0.044). Statistical Parametric Mapping showed that Japanese version of MoCA score correlated with glucose metabolism in the bilateral frontal and parietal lobes, and the left precuneus. CONCLUSION: The total MoCA-J score correlated with amyloid deposition and frontal and parietal glucose metabolism in subjects with mild cognitive impairment. Our findings support the usefulness of the MoCA-J test for screening subjects at high risk for Alzheimer's disease.

High-sensitivity C-reactive protein level is a significant risk factor for silent cerebral infarction in patients on hemodialysis.

In patients with chronic renal failure on hemodialysis (HD), silent cerebral infarctions (SCIs) are associated with high mortality. The levels of high-sensitivity C-reactive protein (HSCRP), a marker of inflammation and atherosclerosis, elevate with increasing renal dysfunction. We tested the hypothesis that increased HSCRP levels correlate with the occurrence of SCI in HD patients. By brain magnetic resonance imaging findings, we divided 54 patients undergoing HD into a with-SCI group (61 +/- 8 years, n = 30) and a without-SCI group (60 +/- 7 years, n = 24). We compared sex, body mass index, metabolic profiles, HSCRP levels, and smoking habits in Japanese patients on HD with and without SCI. We made the following observations: (1) The number of patients with diabetes or hypertension did not differ between the 2 groups. (2) The levels of HSCRP were higher in the with-SCI group in comparison with the without-SCI group (P < .0001). (3) The proportion of smokers was higher in the with-SCI group than in the without-SCI group (P < .05). (4) Plasma levels of high-density lipoprotein cholesterol were lower, whereas uric acid was higher, in the with-SCI group than in the without-SCI group (P < .05 and P < .0001, respectively). (5) Multivariate logistic analysis identified HSCRP levels as being significantly associated with the presence of SCI (odds ratio, 1.61; 95% confidence interval, 1.17-2.85; P < .001). This study indicates that patients in chronic renal failure who are maintained on HD exhibit an increased prevalence of SCI and that HSCRP is significantly associated with the presence of SCI in HD patients.

Functional brain mapping during recitation of Buddhist scriptures and repetition of the Namu Amida Butsu: a study in experienced Japanese monks.

BACKGROUND: The invocation Namu Amida Butsu (Nembutsu), voices the hope of rebirth into Amida's Pure Land. In the Nembutsu, Buddhists imagine that they are absorbed into Amida's Pure Land. Shiritori, a Japanese word chain game, is a common task used to activate language related regions in Japanese. The purpose of this study was to identify the regions activated during praying of the Namo Amida Butsu (Nembutsu), and the reciting of Buddhist scriptures (Sutra). MATERIAL AND METHOD: Functional MRI (fMRI) was used to identify the regions activated by the Nenbutsu, the Sutra and the Shiritori in eight highlytrained Japanese monks. RESULTS: The task of repeating the Nenbutsu activates the medial frontal gyrus, which is mainly related to mental concentration and visuospatial attention, similar to the areas activated by meditation. The task of reciting the Sutra activates the left lateral middle frontal gyrus, the right angular gyrus, and the right supramarginal gyrus, which are related to visuospatial attention also involved in the area activated by meditation. CONCLUSION: These results suggest that different types of meditation in Japanese Buddhism showed different brain regional activation. The Nenbutsu activated the prefrontal cortex, and the Sutra activated the left dorsolateral prefrontal cortex and right parietal cortex.

Predictors for silent cerebral infarction in patients with chronic renal failure undergoing hemodialysis.

In patients with chronic renal failure undergoing hemodialysis (HD), silent cerebral infarctions (SCIs) are associated with high mortality. Levels of hepatocyte growth factor (HGF) increase with renal dysfunction and may be a novel predictor of cerebrovascular events. We examined if HGF is a predictor of SCI in HD patients. Brain magnetic resonance imaging findings were used to divide 50 patients undergoing HD into 2 groups, a group with SCI (age, 61 +/- 8 years, mean +/- SD; n = 27) and a group without SCI (age, 60 +/- 7 years; n = 23). These patients received 24-hour ambulatory blood pressure monitoring. The number of patients with diabetes or hypertension was not different between the 2 groups. We made the following observations: (1) The percentage of smokers was higher in the group with SCI than in the group without SCI (P < .05). (2) Plasma levels of high-density lipoprotein cholesterol were lower and HGF levels were higher in the group with SCI compared with the group without SCI (P < .05 and P < .005, respectively). (3) Systolic ambulatory blood pressure and mean heart rate at night were higher in the group with SCI than in the group without SCI (P < .05). Multiple logistic regression analysis identified HGF as a significant risk factor for SCI (odds ratio, 1.89; 95% confidence interval, 1.57-3.38; P < .005). Our findings indicate that HGF may be a novel useful predictor of SCI in patients with chronic renal failure undergoing HD.

Hyperhomocysteinemia is a significant risk factor for silent cerebral infarction in patients with chronic renal failure undergoing hemodialysis.

In patients with chronic renal failure undergoing hemodialysis (HD), the presence of silent cerebral infarction (SCI) is associated with high mortality. Plasma total homocysteine (tHcy), which increases with renal dysfunction, has been flagged as a novel predictor for cerebrovascular events. We tested the hypothesis that the presence of SCI correlates with tHcy in HD patients. Based on brain magnetic resonance imaging findings, 44 patients undergoing HD were divided into a with-SCI group (61+/-9 years [mean+/-SD]; n=24) and a without-SCI group (60+/-8 years, n=20), in whom 24-hour ambulatory blood pressure monitoring was performed. The number of patients with diabetes or hypertension was not different between the 2 groups. We made the following observations: (1) the percentage of smokers was higher in the with-SCI group than in the without-SCI group (P<.05); (2) plasma levels of high-density lipoprotein cholesterol were lower and tHcy was higher in the with-SCI group than in the without-SCI group (P<.05 and P<.0001, respectively); (3) and systolic ambulatory blood pressure and mean heart rate during nighttime were higher in the with-SCI group than in the without-SCI group (P<.05). Multivariate logistic analysis identified hyperhomocysteinemia as an independent and significant risk factor for SCI (odds ratio, 1.22; 95% CI, 1.10-1.36; P<.01). Our findings indicate that plasma tHcy may be a novel useful predictor for SCI in patients with chronic renal failure undergoing HD.

Identification of the neural correlates of cyclothymic temperament using a working memory task in fMRI.

BACKGROUND: Recently, we reported a significantly negative association of cyclothymic temperament scores with activations of the left lingual gyrus during esthetic judgments of paintings, suggesting that cyclothymic temperament may be associated with the left lingual gyrus. In view of potential associations of cyclothymic temperament, bipolar disorder and dementia, this study examined the relationship of temperament to lingual gyrus activity using a working memory task as a new context. METHODS: N-back tasks (0-, 1-, 2- and 3-back tasks) were performed on 34 healthy subjects using functional MRI. Multiple regression analyses were applied to measure the association between cyclothymic temperament scores and each of 4 beta images corresponding to 0-, 1-, 2- and 3-back tasks with gender, age and the other temperament scores (depressive, hyperthymic, irritable and anxious) as covariates. RESULTS: The whole brain analysis corrected for multiple comparisons revealed a significant activation of the left lingual gyrus associated with cyclothymic temperament scores in a new context-working memory for both 2- and 3-back tasks. LIMITATIONS: The number of subjects was relatively small. The subjects were almost medical staff or students and the results should be interpreted with caution. CONCLUSIONS: The present findings reconfirm that cyclothymic temperament may be associated with the left lingual gyrus.

Association between affective temperaments and regional gray matter volume in healthy subjects.

BACKGROUND: Affective temperaments such as cyclothymic and hyperthymic temperaments have been regarded as potential antecedents of bipolar disorder but the neural substrates underlying these temperaments have not been identified. The aim of this study is to determine whether these temperaments are associated with specific neural substrates in regional brain morphology in healthy subjects. METHODS: We conducted a cross-sectional neuroimaging study of 60 healthy subjects (30 males and 30 females) with affective temperaments. All participants underwent the Mini-International Neuropsychiatric Interview (MINI) to screen for the past and present psychiatric disorder. The scores of cyclothymic and hyperthymic temperaments were measured by the Temperament Scale of Memphis, Pisa, Paris and San Diego-Autoquestionnaire. We analyzed the association between voxel-based morphometry of the brain and these affective temperaments. RESULTS: Subjects classified as having high cyclothymic scores had a significantly larger gray matter volume of the left medial frontal gyrus (MFG) than low cyclothymic subjects. High hyperthymic males also had significantly larger gray matter volume of the left MFG than low hyperthymic males, but there was no difference in females. Subjects with both high cyclothymic and high hyperthymic temperaments demonstrated significantly larger gray matter volume of the left MFG than their counterparts. Region of interest analysis revealed that peaks of these clusters showed a significant positive correlation of the regional volume with temperament scores. LIMITATIONS: The subjects were relatively young and the number was relatively small. Due to the nature of a cross-sectional research design, we could not determine the causal relationship between temperament and the volume changes. CONCLUSIONS: These findings suggest that cyclothymic and hyperthymic temperaments in healthy subjects may have their morphological basis in the left MFG.