50 research outputs found
Network Changes during tACS Induced Oscillations
Oscillatory neural activity is considered a basis of signal transmission in brain networks. However, the causal role of neural oscillations in regulating cortico-cortical signal transmission has so far not been directly demonstrated. To date, due to methodological limitations, studies on the online modulatory mechanisms of transcranial alternating current stimulation (tACS)-induced neural oscillations are confined to the primary motor cortex. To address the causal role of oscillatory activity in modulating cortico-cortical signal transmission, we have established a new method using concurrent tACS, transcranial magnetic stimulation (TMS) and electroencephalography (EEG). Through tACS, we introduced 6-Hz (theta) oscillatory activity in the human dorsolateral prefrontal cortex (DLPFC). During tACS, we applied single-pulse TMS over the DLPFC at different phases of tACS and assessed propagation of TMS-induced neural activity with EEG. We show that tACS-induced theta oscillations modulate the propagation of TMS-induced activity in a phase-dependent manner and that phase-dependent modulation is not simply explained by the instantaneous amplitude of tACS. The results demonstrate a phase-dependent modulatory mechanism of tACS at a cortical network level, which is consistent with a causal role of neural oscillations in regulating the efficacy of signal transmission in the brain
Traumatic reactions in train disasters
Objective : The purpose of this study was to examine the relationship between peritraumatic reactions, posttraumatic stress disorder (PTSD) symptoms, and pain in people injured in train disasters. Methods : The participants were injured in a train crash in Japan that left more than 100 dead. There were 218 participants in the analysis, with a mean age of 37.50 ± 14.67 years. Peritraumatic reactions were assessed using the Peritraumatic Distress Inventory. PTSD symptoms were evaluated using the Impact of Event Scale-Revised Japanese-language version. Pain was measured using the Visual Analog Scale. Results : Peritraumatic reactions did not directly affect PTSD symptoms but were found to be associated via latent variables. Regarding pain and PTSD symptoms, intrusive memories were more associated with pain than other symptoms were. There was an associative path from intrusion to pain, but no such path from pain to intrusion. Conclusions : Our results suggest that a therapeutic approach to intrusion may be effective in ameliorating the pain caused by injury. Future research should examine integrated treatment approaches for both PTSD and pain, rather than just for aspects of PTSD
Effect of cognitive function on jumping to conclusion in patients with schizophrenia
The âjumping to conclusionâ (JTC) bias is related to the formation and maintenance of delusions. Higher JTC bias can be based on both neurocognitive dysfunction and social cognitive dysfunction in patients with schizophrenia. The aim of this study was to assess the relationship between JTC bias, neurocognition, and social cognition in patients with schizophrenia.
A total of 22 patients with schizophrenia and 21 controls participated in this study. Neurocognition and social cognition were assessed using the Brief Assessment of Cognition in Schizophrenia (BACS) and Social Cognition Screening Questionnaire (SCSQ), respectively. The JTC bias and the decision confidence were assessed using the beads task.
The patients were classified into the JTC group (with higher JTC bias; nâŻ=âŻ10) and JTC-non group (nâŻ=âŻ12). The JTC group scored significantly lower on verbal memory, working memory, and motor speed sub-scores of BACS than the JTC-non group. No difference in social cognition was observed between the two groups. The decision confidence was predicted by metacognition, which is an SCSQ sub-score. Similarly to the patients, the controls were classified into the JTC group (higher JTC bias; nâŻ=âŻ9) and the JTC-non group (nâŻ=âŻ12). There were no significant differences in neurocognition and social cognition between the control JTC and JTC-non groups.
The present results indicated that JTC bias is related to neurocognition and decision confidence is related to social cognition in patients with schizophrenia. These findings may bridge the gaps between psychotic symptom and cognitive dysfunction in schizophrenia
Psychological state in cancer patients
The psychological state and changes over time of cancer patients in the active treatment stage were classified into emotions by the speech and behavior of the patient described in the medical record article of the cancer psychological interview record, and the analysis of the âemotional state mapâ was attempted. In all cases, positive / negative emotions were mixed and appeared with variation, but a relatively large number of positive emotions, including , , and , were manifested, and the same was true in patients who experienced stressful treatment events. In the background, the existence of appropriate support from medical professionals and psychological characteristics peculiar to the stage of active treatment was inferred, such as the active treatment of the target patient, the hospitalization environment in which mental and physical pain promptly appealed to medical professionals, and the influence of psychological interviews. Cancer patients during active treatment perceived and expressed changes in the body and pain caused by the disease, and after responses from medical professionals and family members, they were conscious of their physical condition and emotions. It is suggested that this analysis method helps to objectively understand and explain the invisible and ever-changing psychological state of cancer patients in the active treatment stage
CBT Reduces CBF
Background: Imaging studies have provided evidence that cognitiveâbehavioral therapy (CBT ) is able to change brain activation in phobic patients in response to threatening stimuli. The changes occurred in both emotionâgenerating and modulatory regions. In this study, we use a dataâdriven approach to explore resting state cerebral blood flow (CBF ) measured by arterial spin labeling (ASL ), before and after CBT. Methods: Eight female patients with spider phobia were scanned before and 1 month after an exposureâbased group therapy for spider phobia. Each MRI session consisted of an ASL resting state measurement acquired before and after a symptom provocation task involving the showing of spider pictures in the scanner. The first ASL acquisition measured anticipatory anxiety and the second measured postprocessing of phobiaârelevant stimuli. Results: Cognitiveâbehavioral therapy significantly reduced spider phobic symptoms in all patients. Symptom reduction during anticipatory anxiety was accompanied by reduced bilateral CBF in the parahippocampal gyrus, ventral anterior thalamus, Brodmann area 8, and the anterior cingulate cortex. During postprocessing of phobiaârelevant stimuli, patients showed reduced CBF in the bilateral insula, components of the motor cortex, and areas associated with language functions. Conclusions: Longitudinal CBF dynamics following CBT were in concordance with results from several studies using BOLD fMRI to investigate the effects of psychotherapy on brain activity. CBF can be quantified by ASL , with the principal advantage of sensitivity to slow variations in neural activity and task independence. Therefore, ASL may be a suitable method for monitoring and evaluating the efficacy of psychotherapy or pharmacotherapy approaches
Clinical factors influencing resilience in patients with anorexia nervosa
Purpose: This study was to elucidate clinical factors influencing resilience in anorexia nervosa (AN) patients.
Patients and methods: Twenty female patients with AN (median age =30.0 years, quartile deviation =6.8) and 40 female healthy controls (HCs) (median age =30.0 years, quartile deviation =8.6) participated in the present study. Resilience was assessed with the ConnorâDavidson resilience scale (CD-RISC). Clinical symptoms were evaluated with the structured interview guide for the Hamilton depression rating scale (SIGH-D) and the eating disorder inventory-2 (EDI-2).
Results: Scores of the CD-RISC in the AN group were lower than those in the HC group, and the SIGH-D score in the AN group was higher than that in the HC group. Scores of interoceptive confusion, interpersonal difficulty and negative self-image subscales of the EDI-2 negatively correlated with the CD-RISC score. Moreover, stepwise regression analysis showed that negative self-image score was an independent predictor of the CD-RISC score.
Conclusion: These results suggest that among these clinical factors including psychopathologies, self-dissatisfaction and feeling of being rejected by others are the most important influencing factors on an AN patientsâ resilience
Left Side Electrode of DBS Caused an Acute Mood Swing
No previous reports have described a case in which deep brain stimulation elicited an acute mood swing from a depressive to manic state simply by switching one side of the bilateral deep brain stimulation electrode on and off. The patient was a 68-year-old woman with a 10-year history of Parkinsonâs disease. She underwent bilateral subthalamic deep brain stimulation surgery. After undergoing surgery, the patient exhibited hyperthymia. She was scheduled for admission. On the first day of admission, it was clear that resting tremors in the right limbs had relapsed and her hyperthymia had reverted to depression. It was discovered that the left-side electrode of the deep brain stimulation device was found to be accidentally turned off. As soon as the electrode was turned on, motor impairment improved and her mood switched from depression to mania. The authors speculate that the lateral balance of stimulation plays an important role in mood regulation. The current report provides an intriguing insight into possible mechanisms of mood swing in mood disorders
Folate and gender in schizophrenia
Aim: Gender differences in serum folate concentrations are well known, but no studies have investigated the association between serum folate levels and schizophrenia based on gender. In this study in a Japanese population, we examined the difference in serum folate levels between patients with schizophrenia and nonâpsychiatric controls stratified by gender. The relationships between serum folate levels, plasma total homocysteine (tHcy) and serum vitamin B6 (pyridoxal) levels were also examined using data from our previous studies.
Methods: The serum folate concentrations of 482 patients diagnosed with schizophrenia and 1,350 nonâpsychiatric control subjects were measured. We conducted an analysis of covariance to examine the differences in serum folate levels between the two groups based on gender. Spearmanâs rank correlation was used to evaluate the relationships between folate, tHcy and vitamin B6 levels.
Results: In the control group, serum folate concentrations were higher in women than in men. Lower levels of serum folate were observed in both male and female patients with schizophrenia. An inverse correlation between serum folate and plasma tHcy and a weak positive correlation between serum folate and vitamin B6 were observed in the combined cohort.
Conclusion: Our findings suggest that (1) a low serum folate level may be associated with schizophrenia regardless of gender, and (2) folate administration may be beneficial for the treatment of schizophrenia. In schizophrenic patients with low serum folate levels, folate administration might result in improvements in high tHcy and an increase in low vitamin B6 levels
Blood glutamate levels were significantly higher in MDD patients
Purpose: There is growing evidence that glutamatergic signaling may be involved in major depressive disorder (MDD). In regard to peripheral blood glutamate changes in MDD, inconsistent findings have been reported. The purpose of the present study was to evaluate whether blood glutamate levels differed between MDD patients and control participants.
Materials and methods: We conducted a systematic review and meta-analysis of 12 association studies between blood glutamate levels and MDD in a total of 529 MDD patients and 590 controls. Subsequently, we conducted subgroup analyses and a meta-regression analysis to examine the sources of potential heterogeneity.
Results: A random effects model showed that blood glutamate levels were significantly higher in MDD patients than in controls (standardized mean difference=0.54, 95% CI=0.27â0.82, p=8.5Ă10-5) with high heterogeneity (I2=75.0%, p<0.05). Subgroup analyses showed elevated glutamate levels in MDD patients compared with controls in plasma, but not serum studies, and in studies using high-performance liquid chromatography but not with mass spectrometry for glutamate assay. A meta-regression analysis showed no effects of age, gender, medication use, sample size, and published year on blood glutamate levels.
Conclusion: Our findings suggest that altered glutamate levels may be implicated in MDD, which provides further evidence of glutamatergic dysfunction in MDD
Social and cognitive functions in schizophrenia
Purpose: The purpose of the present study was to examine clinical factors related to social function in people with schizophrenia.
Patients and methods: The participants were 55 stabilized outpatients with schizophrenia. Their mean age was 39.36 (SD =10.65) years. Social function was assessed using the Quality of Life Scale (QLS). Cognitive function was evaluated with the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB). Clinical symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale for Schizophrenia, and the Drug-Induced Extrapyramidal Symptoms Scale.
Results: Neither the MCCB cognitive domain score nor composite score was correlated with the QLS scores. However, of the 10 MCCB subtests, the Trail Making Test Part A and the Brief Assessment of Cognition in Schizophrenia-Symbol Coding (BACS-SC) scores were positively correlated with the QLS scores. Among clinical variables, especially the PANSS negative syndrome scale score had a strong negative correlation with the QLS scores. Stepwise regression analyses showed that the PANSS negative syndrome scale score was an independent predictor of the QLS scores, and although the BACS-SC score predicted the QLS common objects and activities subscale score, the association was not so strong compared to the PANSS negative syndrome scale score.
Conclusion: These results indicate that speed of processing evaluated by BACS-SC could predict some aspect of social function but negative symptoms have a much stronger impact on global social function in people with schizophrenia