Hazlett E A, Buchsbaum M S, Haznedar M M, Singer M B, Germans M K, Schnur D B, Jimenez E A, Buchsbaum B R, Troyer B T
Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029-6574, USA.
Psychophysiology. 1998 Mar;35(2):186-98.
Attentional modulation of the startle reflex was studied in 16 unmedicated schizophrenia patients and 15 control individuals during the 18F-2-deoxyglucose uptake period for positron emission tomography. In a task involving attended, ignored, and novel tones that served as prepulses, control individuals showed greater prepulse inhibition (PPI) at 120 ms and greater prepulse facilitation at 4,500 ms during attended than during ignored prepulses; the amount of PPI and facilitation during novel prepulses was intermediate. In contrast, patients failed to show differential PPI at 120 ms and tended to show greater facilitation at 4,500 ms during novel prepulses. For control individuals, greater PPI was associated with higher relative metabolic activity rates in prefrontal (Brodmann Areas 8, 9, and 10 bilaterally) and lower in visual cortex. Patients showed this relationship only for Area 10 on the left. Patients also had low metabolism in superior, middle, and inferior prefrontal cortex. Consistent with animal models, our results demonstrate the importance of the functional integrity of prefrontal cortex to PPI modulation.
在正电子发射断层扫描的18F-2-脱氧葡萄糖摄取期，对16名未用药的精神分裂症患者和15名对照个体进行了惊吓反射的注意调制研究。在一项涉及作为预脉冲的被注意、被忽视和新异音调的任务中，对照个体在被注意的预脉冲期间，在120毫秒时表现出更大的预脉冲抑制（PPI），在4500毫秒时表现出比被忽视的预脉冲更大的预脉冲易化；新异预脉冲期间的PPI和易化量处于中间水平。相比之下，患者在120毫秒时未表现出差异PPI，并且在新异预脉冲期间在4500毫秒时倾向于表现出更大的易化。对于对照个体，更大的PPI与双侧前额叶（布罗德曼区8、9和10）更高的相对代谢活动率以及视觉皮层更低的相对代谢活动率相关。患者仅在左侧的10区表现出这种关系。患者在额上回、额中回和额下回也有低代谢。与动物模型一致，我们的结果证明了前额叶皮层功能完整性对PPI调制的重要性。
