Alkozei Anna, Creswell Cathy, Cooper Peter J, Allen John J B
University of Reading, United Kingdom; University of Arizona, United States.
University of Reading, United Kingdom.
J Affect Disord. 2015 Apr 1;175:25-33. doi: 10.1016/j.jad.2014.11.056. Epub 2014 Dec 6.
Psychophysiological theories suggest that individuals with anxiety disorders may evidence inflexibility in their autonomic activity at rest and when responding to stressors. In addition, theories of social anxiety disorder, in particular, highlight the importance of physical symptoms. Research on autonomic activity in childhood (social) anxiety disorders, however, is scarce and has produced inconsistent findings, possibly because of methodological limitations.
The present study aimed to account for limitations of previous studies and measured respiratory sinus arrhythmia (RSA) and heart rate (HR) using Actiheart heart rate monitors and software (Version 4) during rest and in response to a social and a non-social stressor in 60 anxious (30 socially anxious and 30 'other' anxious), and 30 nonanxious sex-and age-matched 7-12 year olds. In addition, the effect of state anxiety during the tasks was explored.
No group differences at rest or in response to stress were found. Importantly, however, with increases in state anxiety, all children, regardless of their anxiety diagnoses showed less autonomic responding (i.e., less change in HR and RSA from baseline in response to task) and took longer to recover once the stressor had passed.
This study focused primarily on parasympathetic arousal and lacked measures of sympathetic arousal.
The findings suggest that childhood anxiety disorders may not be characterized by inflexible autonomic responding, and that previous findings to the contrary may have been the result of differences in subjective anxiety between anxious and nonanxious groups during the tasks, rather than a function of chronic autonomic dysregulation.
心理生理学理论表明，焦虑症患者在静息状态以及应对压力源时，其自主神经活动可能表现出灵活性不足。此外，社交焦虑症理论尤其强调身体症状的重要性。然而，关于儿童（社交）焦虑症自主神经活动的研究较少，且结果不一致，这可能是由于方法学上的局限性所致。
本研究旨在克服以往研究的局限性，使用Actiheart心率监测器及软件（版本4），对60名焦虑儿童（30名社交焦虑儿童和30名“其他”焦虑儿童）以及30名性别和年龄匹配的7至12岁非焦虑儿童在静息状态下、应对社交和非社交压力源时的呼吸性窦性心律不齐（RSA）和心率（HR）进行测量。此外，还探讨了任务期间状态焦虑的影响。
在静息状态或应对压力时未发现组间差异。然而，重要的是，随着状态焦虑的增加，所有儿童，无论其焦虑诊断如何，自主神经反应均减少（即，任务期间HR和RSA相对于基线的变化较小），且压力源过后恢复所需时间更长。
本研究主要关注副交感神经兴奋，缺乏交感神经兴奋的测量。
研究结果表明，儿童焦虑症可能并非以自主神经反应缺乏灵活性为特征，先前相反的研究结果可能是由于任务期间焦虑组和非焦虑组主观焦虑存在差异，而非慢性自主神经调节异常所致。
