Triple network dysfunction theory of schizophrenia postulates that the interaction between the default-mode and the fronto-parietal executive network is disrupted by aberrant salience signals from the right anterior insula (rAI). To date, it is not clear how the proposed resting-state disruption translates to task-processing inefficiency in subjects with schizophrenia. Using a contiguous resting and 2-back task performance fMRI paradigm, we quantified the change in effective connectivity that accompanies rest-to-task state transition in 29 clinically stable patients with schizophrenia and 31 matched healthy controls. We found an aberrant task-evoked increase in the influence of the rAI to both executive (Cohen’s d = 1.35, p = 2.8 × 10⁻⁶) and default-mode (Cohen’s d = 1.22, p = 1.5 × 10⁻⁵) network regions occur in patients when compared to controls. In addition, the effective connectivity from middle occipital gyrus (dorsal visual cortex) to insula is also increased in patients as compared with healthy controls. Aberrant insula to executive network influence is pronounced in patients with more severe negative symptom burden. These findings suggest that control signals from rAI are abnormally elevated and directed towards both task-positive and task-negative brain regions, when task-related demands arise in schizophrenia. This aberrant, undiscriminating surge in salience signalling may disrupt contextually appropriate allocation of resources in the neuronal workspace in patients with schizophrenia.

精神分裂症的三重网络功能障碍理论假设默认模式和额顶叶执行网络之间的相互作用受到来自右前岛叶（rAI）的异常显着信号的干扰。迄今为止，尚不清楚所提出的静息状态中断如何转化为精神分裂症受试者的任务处理效率低下。使用连续静息和 2-back 任务表现 fMRI 范式，我们量化了 29 名临床稳定的精神分裂症患者和 31 名匹配的健康对照者伴随休息到任务状态转换的有效连接的变化。我们发现rAI对执行网络（Cohen's d  = 1.35，p  = 2.8 × 10 ⁻⁶）和默认模式（Cohen's d  = 1.22，p  = 1.5 × 10 ⁻⁵）网络的影响均出现异常的任务诱发增加。与对照组相比，患者体内出现了区域。此外，与健康对照相比，患者中枕中回（背侧视觉皮层）到岛叶的有效连接也有所增加。异常岛叶对执行网络的影响在负性症状负担更严重的患者中更为明显。这些发现表明，当精神分裂症患者出现与任务相关的需求时，来自 rAI 的控制信号异常升高，并定向到任务积极和任务消极的大脑区域。这种异常的、不加区别的显着信号激增可能会扰乱精神分裂症患者神经元工作空间中资源的适当分配。