From the Emotion and Development Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD (Abend, Bajaj, Harrewijn, Matsumoto, Leibenluft, Pine); the Department of Psychology, University of California Riverside, Riverside, CA (Michalaska); the 3 National Center for Complementary and Integrative Health, National Institutes of Health, Bethesda, MD (Necka, Atlas); and the 1 Department of Psychology, University of Pittsburgh, Pittsburgh, PA (Palacios-Barrios).
J Psychiatry Neurosci. 2021 Mar 11;46(2):E212-E221. doi: 10.1503/jpn.200110.
Threat anticipation engages neural circuitry that has evolved to promote defensive behaviours; perturbations in this circuitry could generate excessive threat-anticipation response, a key characteristic of pathological anxiety. Research into such mechanisms in youth faces ethical and practical limitations. Here, we use thermal stimulation to elicit pain-anticipatory psychophysiological response and map its correlates to brain structure among youth with anxiety and healthy youth.
Youth with anxiety (n = 25) and healthy youth (n = 25) completed an instructed threat-anticipation task in which cues predicted nonpainful or painful thermal stimulation; we indexed psychophysiological response during the anticipation and experience of pain using skin conductance response. High-resolution brain-structure imaging data collected in another visit were available for 41 participants. Analyses tested whether the 2 groups differed in their psychophysiological cue-based pain-anticipatory and pain-experience responses. Analyses then mapped psychophysiological response magnitude to brain structure.
Youth with anxiety showed enhanced psychophysiological response specifically during anticipation of painful stimulation (b = 0.52, p = 0.003). Across the sample, the magnitude of psychophysiological anticipatory response correlated negatively with the thickness of the dorsolateral prefrontal cortex (pFWE < 0.05); psychophysiological response to the thermal stimulation correlated positively with the thickness of the posterior insula (pFWE < 0.05).
Limitations included the modest sample size and the cross-sectional design.
These findings show that threat-anticipatory psychophysiological response differentiates youth with anxiety from healthy youth, and they link brain structure to psychophysiological response during pain anticipation and experience. A focus on threat anticipation in research on anxiety could delineate relevant neural circuitry.
威胁预期涉及到进化而来的促进防御行为的神经回路；该回路的干扰可能会产生过度的威胁预期反应，这是病理性焦虑的一个关键特征。在年轻人中研究这种机制面临着伦理和实际的限制。在这里，我们使用热刺激来引发疼痛预期的心理生理反应，并在焦虑症青年和健康青年中映射其与大脑结构的相关性。
焦虑症青年（n=25）和健康青年（n=25）完成了一项指令性威胁预期任务，其中线索预测非疼痛或疼痛性热刺激；我们使用皮肤电反应来标记预期和体验疼痛时的心理生理反应。在另一项访问中收集了 41 名参与者的高分辨率脑结构成像数据。分析测试了这两组在基于线索的疼痛预期和疼痛体验反应方面是否存在差异。然后分析将心理生理反应幅度映射到大脑结构上。
焦虑症青年在预期疼痛刺激时表现出更强的心理生理反应（b=0.52，p=0.003）。在整个样本中，心理生理预期反应的幅度与背外侧前额叶皮质的厚度呈负相关（pFWE<0.05）；心理生理对热刺激的反应与后岛叶的厚度呈正相关（pFWE<0.05）。
限制包括样本量较小和横断面设计。
这些发现表明，威胁预期的心理生理反应可以将焦虑症青年与健康青年区分开来，并且它们将大脑结构与疼痛预期和体验时的心理生理反应联系起来。在焦虑症研究中关注威胁预期可以描绘出相关的神经回路。
