FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain.
FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain.
Schizophr Res. 2018 Nov;201:224-230. doi: 10.1016/j.schres.2018.06.013. Epub 2018 Jun 25.
Brain functional changes reported in schizophrenia include reduced prefrontal cortex activation (hypofrontality), increased frontal activation (hyperfrontality) and failure of de-activation in the medial frontal cortex. The relative importance of these changes is unestablished.
A 'discovery' sample of 32 schizophrenic patients and 32 controls was used to establish regions of altered activation and de-activation in the patients. The discriminatory power of these regions was examined using receiver-operator characteristics (ROC) analysis in two 'test' samples, one of 83 patients with chronic schizophrenia and 83 healthy controls, and the other of 31 first-episode patients and 31 healthy controls.
The discovery sample revealed reduced activation in the prefrontal cortex and other regions, and failure of de-activation in the medial frontal cortex. Failure of de-activation had significantly greater power to distinguish the chronic patients from the healthy controls than hypoactivation. The pattern was similar in the first-episode patients, where additionally the discriminatory power of hypoactivation was poor. Controlling for the effects of n-back task performance tended to reduce discriminatory power overall, but this persisted for failure of de-activation in the chronic test sample.
Both hypoactivation and failure of de-activation can distinguish patients with chronic schizophrenia from healthy subjects, but the latter abnormality has more power. Failure of de-activation cannot be construed simply as a passive consequence of reduced prefrontal activation in the disorder.
精神分裂症患者的大脑功能变化包括前额叶皮层激活减少（低前额叶功能）、前额叶激活增加（高前额叶功能）和内侧前额叶皮层去激活失败。这些变化的相对重要性尚未确定。
使用 32 名精神分裂症患者和 32 名对照的“发现”样本，确定患者中激活和去激活改变的区域。使用接收器操作特性（ROC）分析在两个“测试”样本中检查这些区域的区分能力，一个包括 83 名慢性精神分裂症患者和 83 名健康对照者，另一个包括 31 名首发精神分裂症患者和 31 名健康对照者。
发现样本显示前额叶皮层和其他区域的激活减少，以及内侧前额叶皮层的去激活失败。去激活失败在区分慢性患者与健康对照组方面的能力显著大于低激活。首发精神分裂症患者的模式类似，其中低激活的区分能力较差。控制 n-back 任务表现的影响往往会降低整体区分能力，但在慢性测试样本中，去激活失败的情况仍然存在。
低激活和去激活失败都可以区分慢性精神分裂症患者和健康受试者，但后者的异常更具影响力。去激活失败不能简单地被视为该疾病中前额叶激活减少的被动后果。
