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.
調査の概要
詳細な説明
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).
研究の種類
入学 (予想される)
段階
- 適用できない
連絡先と場所
研究連絡先
- 名前：Christian Plewnia, MD
- 電話番号：++49 (0)7071-2986121
- メール：christian.plewnia@uni-tuebingen.de
研究場所
-
-
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Muenchen、ドイツ
- 募集
- LMU Muenchen, Department of Psychiatry and Psychotherapy
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コンタクト：
- Alkomiet Hasan, MD
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Tuebingen、ドイツ、72076
- 募集
- University Hospital Tuebigen, Department of Psychiatry and Psychotherapy
-
コンタクト：
- Christian Plewnia, MD
- 電話番号：+49 7071 29 86121
- メール：christian.plewnia@uni-tuebingen.de
-
-
参加基準
適格基準
就学可能な年齢
健康ボランティアの受け入れ
受講資格のある性別
説明
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)
研究計画
研究はどのように設計されていますか？
デザインの詳細
- 主な目的：基礎科学
- 割り当て：ランダム化
- 介入モデル：クロスオーバー割り当て
- マスキング：ダブル
武器と介入
参加者グループ / アーム |
介入・治療 |
|---|---|
|
アクティブコンパレータ：Transcranial direct current stimulation
tDCS with varying intensity, location and polarity
|
他の名前：
|
|
プラセボコンパレーター：Sham stimulation
Double blind sham stimulation with sham mode of neuroConn device
|
他の名前：
|
この研究は何を測定していますか？
主要な結果の測定
結果測定 |
メジャーの説明 |
時間枠 |
|---|---|---|
|
Change of dprime
時間枠：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
|
Assessment during stimulation in a n-back task at three specific timepoints during one week
|
二次結果の測定
結果測定 |
時間枠 |
|---|---|
|
Change of reaction time in n-back task
時間枠：Assessment during stimulation in a n-back task at three specific timepoints during one week
|
Assessment during stimulation in a n-back task at three specific timepoints during one week
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協力者と研究者
捜査官
- 主任研究者：Christian Plewnia, Prof., MD、University Hospital Tuebingen, Department of Psychiatry and Psychotherapy
研究記録日
主要日程の研究
研究開始
一次修了 (予想される)
研究の完了 (予想される)
試験登録日
最初に提出
QC基準を満たした最初の提出物
最初の投稿 (見積もり)
学習記録の更新
投稿された最後の更新 (実際)
QC基準を満たした最後の更新が送信されました
最終確認日
詳しくは
本研究に関する用語
追加の関連 MeSH 用語
その他の研究ID番号
- 01EE1407H
個々の参加者データ (IPD) の計画
個々の参加者データ (IPD) を共有する予定はありますか?
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米国FDA規制機器製品の研究
米国で製造され、米国から輸出された製品。
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