Abstract：
Abnormal cognitive development, particularly working memory (WM) deficits, is among the first apparent manifestations of psychosis. Yet, cognitive impairment only shows limited response to current pharmacological treatment. Alternative interventions to target cognition are highly needed in individuals at high risk for psychosis, like carriers of 22q11.2 deletion syndrome (22q11.2DS). Here we applied theta-tuned transcranial alternating current stimulation (tACS) between frontal and temporal regions during a visual WM task in 34 deletion carriers. We conducted a double-blind sham-controlled study over three consecutive days. The stimulation parameters were derived from individual structural MRI scan and HD-EEG data acquired at baseline (Day 1) to model current intensity and individual preferential theta peak. Participants were randomized to either sham or tACS (Days 2 and 3) and then completed a visual WM task and a control task. Our findings reveal that tACS was safe and well-tolerated among participants. We found a significantly increased accuracy in the visual WM but not the control task following tACS. Moreover, this enhancement in WM accuracy was greater after tACS than during tACS, indicating stronger offline effects than online effects. Our study therefore supports the application of repeated sessions of brain stimulation in 22q11.2DS.
摘要：
认知发育异常,特别是工作记忆(WM)缺陷，是精神病的第一个明显表现。然而，认知障碍对目前的药物治疗仅显示有限的反应。在精神病高风险的个体中，非常需要针对目标认知的替代干预措施，22q11.2缺失综合征(22q11.2DS)的类似携带者。在这里，我们在34个缺失携带者的视觉WM任务中，在额叶和颞叶区域之间应用了theta调谐的经颅交流电刺激（tACS）。我们连续三天进行了双盲假对照研究。刺激参数来源于在基线(第1天)获取的个体结构MRI扫描和HD-EEG数据,以模拟电流强度和个体优先θ峰。参与者被随机分配到假手术或tACS（第2天和第3天），然后完成视觉WM任务和对照任务。我们的研究结果表明，tACS在参与者中是安全且耐受性良好的。我们发现视觉WM的准确性显着提高，但tACS后的控制任务却没有。此外，TACS后WM准确性的这种增强比TACS期间更大，表明离线效应比在线效应更强。因此，我们的研究支持在22q11.2DS中应用重复的脑刺激。
