Resting-State Functional Connectivity as a Predictor of tDCS Effects in Adolescents With Autism Spectrum Disorder
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 90
- 试验地点
- 1
- 主要终点
- Changes in EEG theta coherence
研究概览
简要总结
Background: Transcranial Direct Current Stimulation (tDCS) is a form of non-invasive brain stimulation that has aroused increased interests in the past decade. Not only that it is transient with little side-effects, and can be well-tolerated by children, it is also affordable and readily accessible, making it an appealing treatment option for autism spectrum disorder (ASD).
Objective: (1) To evaluate the therapeutic effects of tDCS on improving cognitive function in patients with ASD, (2) to better understand the neural mechanisms underlying the neuromodulation effects of tDCS in patients with ASD, and (3) to determine whether resting-state functional connectivity measures can predict the therapeutic effects of active tDCS in individuals with ASD.
Methods: To assess the therapeutic effects and neural mechanisms of tDCS, 90 adolescents with ASD (age 12-22 years) will receive three stimulation conditions: cathodal tDCS of the left DLPFC, anodal tDCS of the left DLPFC and sham-tDCS with at least a week apart each time. During the active tDCS or sham-tDCS condition, the participants will be administered a computerized test battery (Cambridge Neuropsychological Test Automated Battery, CANTAB®) to evaluate their cognitive function. EEG before and after the tDCS to evaluate the tDCS-induced alteration in their neural activity and functional connectivity.
Hypothesis: Drawing together the different evidence linking ASD with cortical hyper-excitability and disordered neural connectivity, as reviewed previously, the investigators hypothesize that, relative to a sham-tDCS condition, active cathodal (inhibitory) and anodal (excitatory) tDCS over the left DLPRC will induce stimulation-linked facilitation of learning and resultant improvement of cognitive functioning in patients with ASD.
In addition to the therapeutic effects of tDCS, enhanced neural connectivity, as indexed by altered level EEG theta coherence in patients with ASD, will mediate the beneficial effects of tDCS, relative to sham tDCS, on improvements in cognitive function. Moreover, resting-state functional connectivity will moderate the beneficial effects of active tDCS on cognitive function, relative to sham tDCS, such that participants with greater pre-treatment resting state functional connectively will evidence greater/less response to tDCS, relative to participants receiving sham tDCS.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Triple (Participant, Care Provider, Outcomes Assessor)
入排标准
- 年龄范围
- 12 Years 至 22 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •being 12-22 years old
- •diagnosed with ASD given by registered psychiatrists or clinical psychologists according to the Diagnostic and Statistical Manual of Mental Disorders-5th Edition (DSM-5) criteria of ASD
- •able to communicate in Chinese
排除标准
- •without a confirmed diagnosis from the clinical psychologist
- •history of other neurological and psychiatric disorders and head trauma
- •on psychiatric medication
研究组 & 干预措施
Cathodal active tDCS
For cathodal tDCS condition, participants will receive cathodal stimulation on the dorsolateral prefrontal cortex with ramp up and ramp down mode for 10 seconds, eliciting a tingling sensation on the scalp that fades over seconds. Following that, a twenty-minute executive functional task will be initiated five minutes subsequent to the stimulation mode, and the stimulation will be terminated when the task ends.
干预措施: tDCS (Device)
Anodal active tDCS
For anodal tDCS condition, participants will receive anodal stimulation on the dorsolateral prefrontal cortex with ramp up and ramp down mode for 10 seconds, eliciting a tingling sensation on the scalp that fades over seconds. Following that, a twenty-minute executive functional task will be initiated five minutes subsequent to the stimulation mode, and the stimulation will be terminated when the task ends.
干预措施: tDCS (Device)
Sham tDCS
For sham-tDCS condition, participants will receive initial stimulation with ramp up and ramp down mode for 30 seconds, eliciting a tingling sensation on the scalp then it will be discontinued. Participant will also receive the twenty-minute executive functional task five minutes subsequent to the stimulation mode.
干预措施: tDCS (Device)
结局指标
主要结局
Changes in EEG theta coherence
时间窗: Before tDCS session, Right after tDCS session (2 timepoints, up to 20 minutes)
Each participant will be tested individually to collect EEG data. The participants' eyes-open resting condition will be assessed by EEG for 5 minutes, before and after the tDCS to evaluate the tDCS-induced alteration in their neural activity and functional connectivity. Raw data will be processed with the EEGLAB Toolbox using MATLAB® R2019a. Data from 19 electrodes will be used for analysis.
Change in CANTAB® cognitive test - Reaction Time (RTI)
时间窗: During each stimulation session, last around 3mins
RTI assesses motor and mental response speeds, reaction time, response accuracy and impulsivity. It consists of 30 trials with five potential targets and requires participants to make flexible responses as fast as possible to the target stimulus (shown in yellow). Specifically, movement and reaction time will be measured, where shorter duration reflects faster processing speed.
Change in CANTAB® cognitive test - Spatial Working Memory (SWM)
时间窗: During each stimulation session, last around 6mins
SWM assesses retention and manipulation of visuospatial information. The participant should find one yellow "token" in each of a number of boxes and use them to fill up an empty column on the right of the screen by selecting the boxes and using a process of elimination. Error selecting boxes that have already been found to be empty and revisiting boxes which have already been found to contain a token will be measured.
Change in CANTAB® cognitive test - Multitasking Test (MTT): Response Latencies
时间窗: During each stimulation session, last around 8mins
MTT assesses the ability to resolve the interference of task-irrelevant information (stroop-like effect). The test displays an arrow which can appear on either the left or right side of the screen and can point to either the left or right side. In each trial, participants are presented with a cue that indicates which button to press according to two different rules. And the rules that participants have to follow may change from trial to trial in a randomized order. Participant's response latencies will be measured.
Change in CANTAB® cognitive test - Multitasking Test (MTT): Error Scores
时间窗: During each stimulation session, last around 8mins
MTT assesses the ability to resolve the interference of task-irrelevant information (stroop-like effect). The test displays an arrow which can appear on either the left or right side of the screen and can point to either the left or right side. In each trial, participants are presented with a cue that indicates which button to press according to two different rules. And the rules that participants have to follow may change from trial to trial in a randomized order. Participant's error scores will be measured.
Changes in EEG theta coherence
时间窗: Before tDCS session, Right after tDCS session (2 timepoints, up to 20 minutes)
Each participant will be tested individually to collect EEG data. The participants' eyes-open resting condition will be assessed by EEG for 5 minutes, before and after the tDCS to evaluate the tDCS-induced alteration in their neural activity and functional connectivity. Raw data will be processed with the EEGLAB Toolbox using MATLAB® R2019a. Data from 19 electrodes will be used for analysis.
次要结局
未报告次要终点
研究者
Dr Yvonne Han
Associate Professor
The Hong Kong Polytechnic University