Department of Experimental Psychology, Institute of Psychology, Health, and Society, University of Liverpool, UK.
Eur J Pain. 2013 Mar;17(3):324-35. doi: 10.1002/j.1532-2149.2012.00206.x. Epub 2012 Aug 24.
Previous studies have shown increases in experimental pain during induction of a negative emotion with visual stimuli, verbal statements or unpleasant odours. The goal of the present study was to analyse the spatio-temporal activation patterns underlying pain augmentation during negative emotional sounds.
Negative (e.g., crying), positive (e.g., laughter) and neutral (e.g., distant traffic) sound samples of 4 s duration were presented while noxious laser stimuli were administered to the dorsum of the right hand in 16 healthy participants. The electroencephalographic laser-evoked potentials (LEPs) were modelled using six equivalent source dipoles located in the left and right fronto-opercular/anterior-insular cortex, left parietal operculum, left primary somatosensory cortex, medial parietal cortex and left medial temporal cortex.
Negative emotional sounds were associated with stronger pain than neutral or positive sounds. The source activity in the left medial temporal cortex, purportedly involving hippocampal formation, in the epoch 294-330 ms was greater during negative than neutral or positive sounds. In the left fronto-opercular/anterior-insular cortex, negative sounds failed to show the positive potential component at around 260 ms that was observed during positive and especially during neutral sounds.
Results suggest increased input of pain-related information into the hippocampal formation when listening to negative emotional sounds, which may in turn facilitate temporal binding between representations of noxious and other behaviourally relevant stimuli, and perhaps associative learning. Absence of the positive potential component fronto-opercular/anterior-insular cortex during negative sounds points to a slow attentional disengagement from pain and increased awareness of the painful stimulus.
先前的研究表明，在使用视觉刺激、言语陈述或不愉快气味诱发负面情绪时，实验性疼痛会增加。本研究的目的是分析负面情绪声音引起疼痛增强时的时空激活模式。
16 名健康参与者的右手背部接受有害激光刺激的同时，呈现持续 4s 的负面（例如，哭泣）、正面（例如，笑声）和中性（例如，远处的交通）声音样本。使用位于左、右额顶叶/前岛叶和左顶叶外侧、左初级体感皮层、内侧顶叶和左内侧颞叶的六个等效源偶极子对激光诱发的脑电图（LEP）进行建模。
负面情绪声音引起的疼痛强于中性或正面声音。在 294-330ms 时程内，左侧颞叶内侧（据称涉及海马结构）的源活动在负性声音时比中性或正性声音时更强。在左侧额顶叶/前岛叶和前岛叶皮层中，负性声音未能显示出大约 260ms 时出现的正电势成分，而正性声音和特别是中性声音时会出现该成分。
结果表明，当聆听负面情绪声音时，与疼痛相关的信息会更多地传入海马结构，这可能反过来促进疼痛和其他行为相关刺激的表示之间的时间绑定，并且可能促进联想学习。在负性声音时，额顶叶/前岛叶皮层中没有正电势成分，这表明对疼痛的注意力难以脱离，对疼痛刺激的意识增强。
