Mathalon Daniel H, Ford Judith M
Psychiatry Service, San Francisco VA Medical Center, USA.
Clin EEG Neurosci. 2008 Apr;39(2):82-6. doi: 10.1177/155005940803900212.
Evidence is accumulating that schizophrenia is characterized by dysfunction of efference copy/corollary discharge mechanisms that normally allow us to unconsciously recognize and disregard sensations resulting from our own actions. This dysfunction may give rise to subtle but pervasive sensory/perceptual aberrations in schizophrenic patients, altering their experience of their own overt and covert actions, as well as their interactions with the environment. It may also contribute to symptoms such as hallucinations and delusions, and may disrupt the motivation to engage with people and in activities. We developed neurophysiological paradigms to study motor-sensory feed-forward processes, or efference copy/corollary discharge mechanisms, in the speech-auditory system, and showed these processes to be deficient in chronic schizophrenia. Specifically, we observed neural responses during talking that made evident the suppressive consequences of a successful corollary discharge mechanism. We also observed synchronous neural activity preceding talking that we believe reflects the efference copy in action. Recently, we extended this neurophysiological research to the somatosensory system, again finding evidence of deficient motor-sensory feed-forward processes in schizophrenia. If dysfunction of this elemental mechanism is reliable, valid, and not the result of antipsychotic medications, it might represent a major new class of electrophysiological measures sensitive to a fundamental and ubiquitous pathophysiological process in schizophrenia.
越来越多的证据表明，精神分裂症的特征是传出副本/伴随放电机制功能失调，而这种机制通常能让我们在无意识的情况下识别并忽略自身行为产生的感觉。这种功能失调可能会在精神分裂症患者身上引发细微但普遍存在的感觉/知觉异常，改变他们对自身公开和隐蔽行为的体验，以及他们与环境的互动。它还可能导致幻觉和妄想等症状，并可能扰乱与他人交往和参与活动的动机。我们开发了神经生理学范式来研究言语-听觉系统中的运动-感觉前馈过程，即传出副本/伴随放电机制，并发现这些过程在慢性精神分裂症患者中存在缺陷。具体而言，我们观察到说话过程中的神经反应，这些反应表明了成功的伴随放电机制的抑制作用。我们还观察到说话之前的同步神经活动，我们认为这反映了传出副本的作用。最近，我们将这项神经生理学研究扩展到了体感系统，再次发现精神分裂症患者存在运动-感觉前馈过程缺陷的证据。如果这种基本机制的功能失调是可靠、有效的，且不是抗精神病药物导致的结果，那么它可能代表了一类主要的新电生理指标，对精神分裂症中一种基本且普遍存在的病理生理过程敏感。
