Burger Andreas M, Verkuil Bart, Van Diest Ilse, Van der Does Willem, Thayer Julian F, Brosschot Jos F
Institute of Psychology, Leiden University, Wassenaarseweg 52, 2333 AK Leiden, The Netherlands.
Faculty of Psychology, Katholieke Universiteit Leuven, Tiensestraat 102, 3000 Leuven, Belgium.
Neurobiol Learn Mem. 2016 Jul;132:49-56. doi: 10.1016/j.nlm.2016.05.007. Epub 2016 May 21.
A critical component of the treatment for anxiety disorders is the extinction of fear via repeated exposure to the feared stimulus. This process is strongly dependent on successful memory formation and consolidation. Stimulation of the vagus nerve enhances memory formation in both animals and humans. The objective of this study was to assess whether transcutaneous stimulation of the vagus nerve (tVNS) can accelerate extinction memory formation and retention in fear conditioned humans. To assess fear conditioning and subsequent fear extinction, we assessed US expectancy ratings, fear potentiated startle responses and phasic heart rate responses. We conducted a randomized controlled trial in thirty-one healthy participants. After fear conditioning participants were randomly assigned to receive tVNS or sham stimulation during the extinction phase. Retention of extinction memory was tested 24h later. tVNS accelerated explicit fear extinction learning (US expectancy ratings), but did not lead to better retention of extinction memory 24h later. We did not find a differential physiological conditioning response during the acquisition of fear and thus were unable to assess potential effects of tVNS on the extinction of physiological indices of fear. These findings complement recent studies that suggest vagus nerve stimulation could be a promising tool to improve memory consolidation and fear extinction.
焦虑症治疗的一个关键组成部分是通过反复接触恐惧刺激来消除恐惧。这个过程强烈依赖于成功的记忆形成和巩固。刺激迷走神经可增强动物和人类的记忆形成。本研究的目的是评估经皮迷走神经刺激(tVNS)是否能加速恐惧条件化人类的消退记忆形成和保持。为了评估恐惧条件化和随后的恐惧消退,我们评估了预期电击评分、恐惧增强的惊吓反应和阶段性心率反应。我们对31名健康参与者进行了一项随机对照试验。在恐惧条件化后,参与者在消退阶段被随机分配接受tVNS或假刺激。24小时后测试消退记忆的保持情况。tVNS加速了明确的恐惧消退学习(预期电击评分),但在24小时后并没有导致更好的消退记忆保持。我们在恐惧习得过程中没有发现不同的生理条件化反应,因此无法评估tVNS对恐惧生理指标消退的潜在影响。这些发现补充了最近的研究,表明迷走神经刺激可能是改善记忆巩固和恐惧消退的一个有前景的工具。