Department of Psychiatry, National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru, India.
Department of Psychiatry, National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru, India.
Neuropsychologia. 2023 Nov 5;190:108683. doi: 10.1016/j.neuropsychologia.2023.108683. Epub 2023 Sep 18.
Self-bias effect is expressed as a preferential selection and accelerated perception of self-related sensory information. Intentional binding (IB) is a related phenomenon where the sensory outcome from a voluntary action and the voluntary action itself are perceived to be closer to each other in time in both predictive (voluntary action predicting sensory consequence) and retrospective (sensory consequence features triggering self-related inference) contexts. Recent evidence indicates that self-related visual stimuli can affect retrospective intentional binding (rIB). We aimed to 1) replicate rIB in the auditory context, and 2) investigate the potential role of left temporoparietal junction (l-TPJ), a crucial node for the self-monitoring process, in self-bias effect and intentional binding effect by manipulating l-TPJ activity with neuromodulation [using High-Definition Transcranial Direct Current Stimulation (HD-tDCS)]. We anticipated self-bias and rIB effects to increase with anodal stimulation of l-TPJ in comparison to cathodal-stimulation of l-TPJ.
Fourteen, right-handed, healthy participants performed sound-label matching (matching tones to self-and-other labels) and rIB (estimating time interval between a button press and a self/other labelled tone) tasks. Each participant underwent both anodal and cathodal stimulation of l-TPJ in separate sessions (at least 72 h apart). Assignment of HD-tDCS type was random and counter-balanced across participants. Behavioural data was collected at three time points: once at baseline (no-stimulation), and twice after stimulation with HD-tDCS.
Strong self-bias effect was observed across all experimental conditions. Neuromodulation of l-TPJ affected processing of other-labelled tone in the sound-label matching task. rIB was noted in baseline and anodal-HD-tDCS conditions where participants exhibited stronger binding for self-associated stimuli compared to other-associated stimuli.
l-TPJ may potentially play a critical role in self-other distinction. This may have possible implications for disorders of self-disturbances like psychosis.
自我偏向效应表现为对自我相关感觉信息的优先选择和加速感知。意图绑定（IB）是一种相关现象，即在预测（自愿行动预测感觉后果）和回顾（感觉后果特征触发自我相关推断）背景下，自愿行动产生的感觉结果和自愿行动本身在时间上彼此更接近。最近的证据表明，与自我相关的视觉刺激会影响回顾性意图绑定（rIB）。我们旨在 1）在听觉背景下复制 rIB，以及 2）通过神经调节[使用高清晰度经颅直流电刺激（HD-tDCS）]来操纵左颞顶联合区（l-TPJ）的活动，来研究 l-TPJ 在自我偏向效应和意图绑定效应中的潜在作用，l-TPJ 是自我监测过程的关键节点。我们预计与 l-TPJ 的阴极刺激相比，l-TPJ 的阳极刺激会增加自我偏向和 rIB 效应。
14 名右利手健康参与者进行了声音标签匹配（将音调与自我和他人标签匹配）和 rIB（估计按钮按下和自我/他人标记音之间的时间间隔）任务。每个参与者在单独的会议中接受 l-TPJ 的阳极和阴极刺激（至少相隔 72 小时）。HD-tDCS 类型的分配是随机的，并在参与者之间平衡。行为数据在三个时间点收集：一次在基线（无刺激），两次在刺激后用 HD-tDCS。
在所有实验条件下都观察到强烈的自我偏向效应。l-TPJ 的神经调节影响声音标签匹配任务中其他标记音的处理。在基线和阳极-HD-tDCS 条件下观察到 rIB，参与者表现出对自我相关刺激的绑定比其他相关刺激更强。
l-TPJ 可能在自我与他人的区分中发挥关键作用。这可能对精神障碍等自我障碍障碍有潜在的影响。
