Canali Paola, Sferrazza Papa Giovanna, Casali Adenauer G, Schiena Giandomenico, Fecchio Matteo, Pigorini Andrea, Smeraldi Enrico, Colombo Cristina, Benedetti Francesco
Department of Clinical Neurosciences, Scientific Institute Ospedale San Raffaele and University Vita-Salute San Raffaele, Milano, Italy.
Bipolar Disord. 2014 Dec;16(8):809-19. doi: 10.1111/bdi.12249. Epub 2014 Sep 15.
It is still unclear which biological changes are needed to recover from a major depressive episode. Current perspectives focus on cortical synaptic neuroplasticity. Measures of cortical responses evoked by transcranial magnetic stimulation (TMS) change with sleep homeostasic pressure in humans and approximate measures of synaptic strength in animal models. Using repeated total sleep deprivation as a model of antidepressant treatment, we aimed to correlate recovery from depression with these measures of cortical excitability.
We recorded electroencephalographic responses to TMS in the prefrontal cortex of 21 depressed inpatients with bipolar disorder treated with repeated sleep deprivation combined with light therapy. We performed seven TMS/electroencephalography sessions during one week and calculated three measures of cortical excitability.
Cortical excitability progressively increased during the antidepressant treatment and as a function of time awake. Higher values differentiated responders from non-responders at baseline and during and after treatment on all measures.
Changes in measures of cortical excitability parallel and predict antidepressant response to combined sleep deprivation and light therapy. Data suggest that promoting cortical plasticity in bipolar depression could be a major effect of successful antidepressant treatments, and that patients not responding could suffer a persistent impairment in their neuroplasticity mechanisms.
目前仍不清楚从重度抑郁发作中恢复需要哪些生物学变化。当前观点聚焦于皮质突触神经可塑性。经颅磁刺激（TMS）诱发的皮质反应测量值会随人类睡眠稳态压力而变化，并且与动物模型中突触强度的近似测量值相关。我们以反复完全睡眠剥夺作为抗抑郁治疗的模型，旨在将抑郁恢复情况与这些皮质兴奋性测量值相关联。
我们记录了21名双相情感障碍抑郁住院患者在接受反复睡眠剥夺联合光疗治疗时前额叶皮质对TMS的脑电图反应。我们在一周内进行了七次TMS/脑电图检查，并计算了三种皮质兴奋性测量值。
在抗抑郁治疗期间以及作为清醒时间的函数，皮质兴奋性逐渐增加。在基线、治疗期间及治疗后，所有测量值中，较高的值可区分反应者与无反应者。
皮质兴奋性测量值的变化与联合睡眠剥夺和光疗的抗抑郁反应平行且可预测该反应。数据表明，促进双相抑郁中的皮质可塑性可能是成功抗抑郁治疗的主要作用，而无反应的患者可能在其神经可塑性机制方面存在持续损害。
