Efficacy and Mechanisms of Transcranial Direct Current Stimulation (tDCS) - Effects on Working Memory in Schizophrenia
Impairments of cognition are a core, severely disabling feature of schizophrenia leading to poor long-term outcome with no established treatment available.
Particularly impaired executive functions (e.g working memory) are frequently observed and are consistently associated with reduced activation of the dorsolateral prefrontal cortex (dlPFC). Deficits in those functions have been shown to be closely related to negative symptoms, thought disorder, and functional outcome in schizophrenia leading to the notion that frontal lobe dysfunction is crucially important in schizophrenic psychopathology.
Noninvasive brain stimulation like tDCS can enhance executive functions like working memory in healthy subjects as well as in patients. To identify the optimal parameters for this intervention in patients with schizophrenia, the investigators first test the effects of different polarities (anodal, cathodal), stimulation intensities (1mA, 2mA) and laterality (left, right) on working-memory performance (nback task) in a sham-controlled cross-over design (n=128). To elucidate mechanisms of action, oscillatory brain activity will be registered with electroencephalography (EEG).
These experiments will provide reliable data for an evidence-based development of new clinical interventions to improve treatment of cognitive deficits in patients with schizophrenia and thus enhance schizophrenia prevention and recovery.
研究概览
详细说明
Working hypothesis:
In patients with subacute schizophrenia, transcranial direct current stimulation (tDCS) to the dorsolateral prefrontal cortex (dlPFC) exerts lasting beneficial effects on working-memory performance.
Research question(s):
In patients with remitted early phase schizophrenia, this research project aims at providing evidence for:
i) immediate improvement of working-memory performance by application of tDCS to the dlPFC in patients with schizophrenia; ii) determination of the optimal stimulation polarity, dosage and localization; iii) neurophysiological mechanisms (modulation in oscillatory activity and functional connectivity) and predictors of tDCS effects; iv) modulating effect of gender on the malleability of executive functions with tDCS.
Previous work of the investigators:
The investigators have provided proof-of principle evidence for persisting improvement of cognitive planning by a polarity-specific learning-stage dependent coupling of training and stimulation. The investigators have demonstrated that working memory and deficient cognitive control can be enhanced with anodal tDCS in depression and that the effects of tDCS are modulated by genetic polymorphisms. The investigators were the first to show impaired cortical plasticity following tDCS in schizophrenia patients at different disease states. Finally, the investigators have just successfully finished the world-wide largest clinical trial investigating the efficacy of non-invasive brain stimulation (rTMS) on negative symptoms in schizophrenia (DFG 241/10-1, Falkai, Hasan).
- Aims and work plan:
To examine the potential of tDCS for the improvement of working memory with remitted schizophrenia the investigators are following this work plan:
I) Immediate effects on performance:
Assessment of efficacy of tDCS polarity (anodal, cathodal), dosage (1mA, 2mA) and laterality (left and right dlPFC) on working memory (adaptive n-back(6)) in patients (n=2x2x2x16=128). In a two-session cross-over design, stimulation (tDCS and sham) will be applied to the dlPFC (left or right) for 20min (during task performance).
研究类型
注册 (预期的)
阶段
- 不适用
联系人和位置
学习联系方式
- 姓名：Christian Plewnia, MD
- 电话号码：++49 (0)7071-2986121
- 邮箱：christian.plewnia@uni-tuebingen.de
学习地点
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Muenchen、德国
- 招聘中
- LMU Muenchen, Department of Psychiatry and Psychotherapy
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接触：
- Alkomiet Hasan, MD
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Tuebingen、德国、72076
- 招聘中
- University Hospital Tuebigen, Department of Psychiatry and Psychotherapy
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接触：
- Christian Plewnia, MD
- 电话号码：+49 7071 29 86121
- 邮箱：christian.plewnia@uni-tuebingen.de
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-
参与标准
资格标准
适合学习的年龄
接受健康志愿者
有资格学习的性别
描述
Inclusion Criteria:
- diagnosed schizophrenia (DSM-V)
- age (18 - 60 years)
- right handedness
- stable medication during 1 week of treatment and 1 week before
Exclusion Criteria:
- history of seizures
- metal device throughout the body
- pregnancy
- use of anticonvulsive medication
- use of benzodiazepines more than 1 mg of Lorazepam equivalent
- current substance abuse (nicotine excluded)
学习计划
研究是如何设计的？
设计细节
- 主要用途：基础科学
- 分配：随机化
- 介入模型：交叉作业
- 屏蔽：双倍的
武器和干预
参与者组/臂 |
干预/治疗 |
|---|---|
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有源比较器：Transcranial direct current stimulation
tDCS with varying intensity, location and polarity
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其他名称：
|
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安慰剂比较：Sham stimulation
Double blind sham stimulation with sham mode of neuroConn device
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其他名称：
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研究衡量的是什么？
主要结果指标
结果测量 |
措施说明 |
大体时间 |
|---|---|---|
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Change of dprime
大体时间：Assessment during stimulation in a n-back task at three specific timepoints during one week
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dprime provides the separation between the means of the signal and the noise distributions, compared against the standard deviation of the signal plus noise distributions
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Assessment during stimulation in a n-back task at three specific timepoints during one week
|
次要结果测量
结果测量 |
大体时间 |
|---|---|
|
Change of reaction time in n-back task
大体时间：Assessment during stimulation in a n-back task at three specific timepoints during one week
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Assessment during stimulation in a n-back task at three specific timepoints during one week
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合作者和调查者
调查人员
- 首席研究员：Christian Plewnia, Prof., MD、University Hospital Tuebingen, Department of Psychiatry and Psychotherapy
研究记录日期
研究主要日期
学习开始
初级完成 (预期的)
研究完成 (预期的)
研究注册日期
首次提交
首先提交符合 QC 标准的
首次发布 (估计)
研究记录更新
最后更新发布 (实际的)
上次提交的符合 QC 标准的更新
最后验证
更多信息
与本研究相关的术语
其他相关的 MeSH 术语
其他研究编号
- 01EE1407H
计划个人参与者数据 (IPD)
计划共享个人参与者数据 (IPD)？
药物和器械信息、研究文件
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研究美国 FDA 监管的设备产品
在美国制造并从美国出口的产品
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