Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Harvard Medical School, MA 02114, USA.
Schizophr Res. 2013 Jan;143(1):150-7. doi: 10.1016/j.schres.2012.10.038. Epub 2012 Nov 30.
Patients with schizophrenia may have altered pain perception, as suggested by clinical reports of pain insensitivity, and recent neuroimaging findings. Here, we examined neural responses to an aversive electrical stimulus and the immediate anticipation of such a stimulus using fMRI and a classical conditioning paradigm, which involved pairing an electrical shock with a neutral photograph. Fifteen men with schizophrenia and 13 healthy men, matched for demographic characteristics, electrical stimulation level and scan movement, were studied. The shock induced robust responses in midbrain, thalamus, cingulate gyrus, insula and somatosensory cortex in both groups. However, compared to controls, the schizophrenic patients displayed significantly lower activation of the middle insula (p(FWE)=0.002, T=5.72, cluster size=24 voxels). Moreover, the lack of insula reactivity in the schizophrenia group was predicted by the magnitude of positive symptoms (r=-0.46, p=0.04). In contrast, there were no significant differences between the two groups in the magnitude of neural responses during anticipation of the shock. These findings provide support for the existence of a basic deficit in interoceptive perception in schizophrenia, which could play a role in the generation and/or maintenance of psychotic states.
精神分裂症患者可能存在疼痛感知改变，这在临床报告中表现为对疼痛不敏感，最近的神经影像学研究也发现了这一点。在这里，我们使用 fMRI 和经典条件反射范式检查了对厌恶电刺激的神经反应和对这种刺激的即时预期，该范式涉及将电击与中性照片配对。我们研究了 15 名男性精神分裂症患者和 13 名在人口统计学特征、电刺激水平和扫描运动方面相匹配的健康男性。在两组中，电击都能引起中脑、丘脑、扣带回、脑岛和躯体感觉皮层的强烈反应。然而，与对照组相比，精神分裂症患者的中间脑岛的激活明显较低（p(FWE)=0.002，T=5.72，簇大小=24 个体素）。此外，精神分裂症组的脑岛反应缺失可由阳性症状的严重程度预测（r=-0.46，p=0.04）。相比之下，两组在预期电击时的神经反应幅度上没有显著差异。这些发现支持了精神分裂症中存在内脏感知基本缺陷的观点，这可能在精神病状态的产生和/或维持中发挥作用。
