Structural differences in the amygdala (AMG) are implicated in anxiety and observed among individuals with generalized (GAD) and social anxiety (SAD) disorders. Findings have been mixed, perhaps because studies rarely examine differences between GAD and SAD, test comorbidity, or examine age-related differences. We tested AMG volume differences among a sample of adults and youth with/without SAD and GAD. Participants (N = 242; ages 7–60 years) completed an MRI scan, diagnostic interviews, and anxiety symptom measures. Groups were formed from diagnostic interviews: 1) Typically developing (TD; n = 91); 2) GAD (n = 53); 3) SAD (n = 35); and 4) comorbid SAD/GAD (n = 63). We used analysis of covariance with a bonferroni correction to examine group differences in AMG volume. The SAD and comorbid SAD/GAD groups exhibited increased bilateral AMG volume compared to the TD group. GAD and TD groups did not differ from each other in AMG size. The SAD, but not the comorbid SAD/GAD group, displayed greater right AMG size relative to the GAD group. SAD and comorbid SAD/GAD groups did not differ from the GAD group in left AMG volume. SAD and SAD/GAD groups did not exhibit different bilateral AMG size. Linear regression analyses demonstrated that greater social anxiety but not generalized anxiety symptom severity was associated with enlarged AMG volume. Age was not associated with AMG volume and nor did age moderate any group or symptom effects. Future longitudinal studies should examine whether larger AMG volume is a unique biomarker for SAD across the lifespan.

杏仁核 (AMG) 的结构差异与焦虑有关，并在患有广泛性 (GAD) 和社交焦虑 (SAD) 障碍的个体中观察到。结果喜忧参半，可能是因为研究很少检查 GAD 和 SAD 之间的差异、测试合并症或检查与年龄相关的差异。我们测试了有/没有 SAD 和 GAD 的成人和青年样本之间的 AMG 体积差异。参与者（N = 242；年龄 7-60 岁）完成了 MRI 扫描、诊断性访谈和焦虑症状测量。小组由诊断性访谈组成：1）典型发展（TD；n  = 91）；2）GAD（n  = 53）；3) 悲伤 ( n  = 35); 和 4) 共病 SAD/GAD ( n = 63）。我们使用具有 bonferroni 校正的协方差分析来检查 AMG 体积的组差异。与 TD 组相比，SAD 和合并症 SAD/GAD 组的双侧 AMG 体积增加。GAD 和 TD 组在 AMG 大小上没有区别。与 GAD 组相比，SAD 组（但不是 SAD/GAD 合并症组）显示出更大的右侧 AMG 大小。SAD 和合并症 SAD/GAD 组在左侧 AMG 体积方面与 GAD 组没有区别。SAD 和 SAD/GAD 组没有表现出不同的双侧 AMG 大小。线性回归分析表明，更大的社交焦虑而不是广泛性焦虑症状的严重程度与 AMG 体积增大有关。年龄与 AMG 体积无关，年龄也不会减轻任何组或症状影响。