Giakoumaki Stella G, Roussos Panos, Rogdaki Maria, Karli Costandina, Bitsios Panos, Frangou Sophia
Department of Psychiatry and Behavioral Sciences, Medical School, University of Crete, Crete, Greece.
Biol Psychiatry. 2007 Dec 15;62(12):1418-22. doi: 10.1016/j.biopsych.2006.12.002. Epub 2007 May 3.
Prepulse inhibition (PPI) of the startle response refers to a reduction in the response to a strong stimulus (pulse) if preceded shortly by a weak stimulus (prepulse). Disrupted PPI is thought to reflect abnormalities in the inhibitory control of information processing. Reduced PPI has been reported in mania, although it is not clear whether it represents a trait feature of bipolar disorder (BD). To address this issue, the present study examined whether disrupted PPI is present in individuals at high risk for BD.
Twenty-one remitted BD patients and 19 of their unaffected siblings were compared with 17 age- and gender-matched healthy volunteers on tests of acoustic startle reactivity and PPI of the startle response.
There were no group differences in startle reactivity. Compared with healthy individuals, BD patients and their unaffected siblings showed lower PPI. In the patient group, no significant correlations were found between PPI and measures of symptom and disease severity or medication.
This is the first study to report reduced PPI in remitted BD patients and their unaffected first-degree relatives. This finding, although in need of replication, suggests that PPI disruption may represent a trait deficit in BD associated with genetic predisposition.
惊吓反应的前脉冲抑制（PPI）是指如果在强刺激（脉冲）之前不久出现弱刺激（前脉冲），则对强刺激的反应会降低。PPI的破坏被认为反映了信息处理抑制控制的异常。虽然目前尚不清楚PPI降低是否代表双相情感障碍（BD）的一种特质特征，但已有研究报道躁狂症患者存在PPI降低的情况。为解决这一问题，本研究调查了BD高危个体中是否存在PPI破坏。
将21名缓解期BD患者及其19名未患病的同胞与17名年龄和性别匹配的健康志愿者进行对比，测试听觉惊吓反应性和惊吓反应的PPI。
惊吓反应性方面不存在组间差异。与健康个体相比，BD患者及其未患病的同胞显示出较低的PPI。在患者组中，未发现PPI与症状、疾病严重程度或药物治疗指标之间存在显著相关性。
这是第一项报道缓解期BD患者及其未患病的一级亲属中PPI降低的研究。这一发现虽然需要重复验证，但表明PPI破坏可能代表与遗传易感性相关的BD特质缺陷。
