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Self-agency is the awareness of being the agent of ones own thoughts and actions. Self-agency is essential for interacting with the outside world (reality-monitoring). The medial prefrontal cortex (mPFC) is thought to be one neural correlate of self-agency. We investigated whether mPFC activity can causally modulate self-agency on two different tasks of speech-monitoring and reality-monitoring. The experience of self-agency is thought to result from making reliable predictions about the expected outcomes of ones own actions. This self-prediction ability is necessary for the encoding and memory retrieval of ones own thoughts during reality-monitoring to enable accurate judgments of self-agency. This self-prediction ability is also necessary for speech-monitoring where speakers consistently compare auditory feedback (what we hear ourselves say) with what we expect to hear while speaking. In this study, 30 healthy participants are assigned to either 10 Hz repetitive transcranial magnetic stimulation (rTMS) to enhance mPFC excitability (N = 15) or 10 Hz rTMS targeting a distal temporoparietal site (N = 15). High-frequency rTMS to mPFC enhanced self-predictions during speech-monitoring that predicted improved self-agency judgments during reality-monitoring. This is the first study to provide robust evidence for mPFC underlying a causal role in self-agency, that results from the fundamental ability of improving self-predictions across two different tasks.

To further improve the application quality of the waterborne epoxy resin (WER) in road engineering, a variety of WER and polyurethane-modified WER were prepared. The WER was treated by acid solution immersion, alkali solution immersion, salt solution immersion, oil immersion or artificial-accelerated aging. The mechanical properties of the WER before and after the treatment by various methods were tested. Based on the ideal point method of entropy weight, the influence degree of each treatment method on the mechanical properties of the WER was analysed, and the mechanical properties decay and residual mechanical properties of the WER were evaluated. The bonding durability of the WER was analysed. The results show that after the xenon lamp aging treatment, the mechanical properties of the WER decreased most significantly. The mechanical durability of the WER modified by polyurethane is improved to a certain extent, and the retention rates of their mechanical properties are >85%. After treatment by various corrosion or aging methods, the retention rates of mechanical properties of the PUE-E44 WER are >89.29%, showing an improved corrosion and aging resistance. The residual mechanical and bonding properties of the PUD-E51 WER are at a high level, and still show improved mechanical and bonding properties. [ABSTRACT FROM AUTHOR]

A successful efference copy self-prediction suppresses auditory signals in the primary auditory cortex (A1) is necessary for speakers to successfully compare auditory feedback during speech production with auditory feedback during passive listening, this is called speaker-induced suppression (SIS). The top-rank positive symptom in schizophrenic (SZ) patients, auditory verbal hallucination, for instance, is hypothesized to relate to failure to distinguish the internal voice and external sounds, and this deficit is thought to be associated with impaired self-prediction in comparing external and self-generated contents. In this magnetoencephalographic imaging (MEGI) study, we compared SIS M100 in the primary auditory cortex (A1) between the healthy controls (HC; N = 30) and SZ patients (N = 22). The SZ patients displayed reduced SIS and M100 in the A1, and this impairment is negatively correlated with auditory hallucinations. These outcomes suggest that the SZ patients' hallucinatory symptoms are caused by misattribution between the external and self-generated stimuli. We proposed that the weakened self-agency and neural oscillations may lead to this misattribution.