Ankara University, Department of Psychiatry, Brain Research Center, Ankara, Turkey.
Yenimahalle Hospital, Department of Psychiatry, Ankara, Turkey.
Prog Neuropsychopharmacol Biol Psychiatry. 2021 Jan 10;104:110012. doi: 10.1016/j.pnpbp.2020.110012. Epub 2020 Jun 14.
The cognitive and emotional vulnerability of individuals with social anxiety disorder (SAD) and their response to repeated experiences of social rejection and social acceptance are important factors for the emergence and maintenance of symptoms of the disorder. Functional neuroimaging studies of SAD reveal hyperactivity in regions involved in the fear circuit such as amygdala, insula, anterior cingulate, and prefrontal cortices (PFC) in response to human faces with negative emotions. Observation of brain activity, however, involving studies of responses to standardized human interaction of social acceptance and social rejection have been lacking.
We compared a group of index subjects with SAD (N = 22, mean age:26.3 ± 5.4, female/male: 7/15) (SADG) with a group of healthy controls (CG) (N = 21, mean age:28.7 ± 4.5, female/male: 14/7) in measures of cortical activity during standardized experiences of human interaction involving social acceptance (SA) and social rejection (SR) video-simulated handshaking tasks performed by real actors. In a third, control condition (CC), the subjects were expected to press a switch button in an equivalent space. Subjects with a concurrent mood episode were excluded and the severity of subclinical depressive symptoms was controlled. 52-channel functional near-infrared spectroscopy (fNIRS) was used to measure cortical activity.
Activity was higher in the SAD subjects compared to healthy controls, in particular in channels that project to middle and superior temporal gyri (STG), frontal eye fields (FEF) and dorsolateral prefrontal cortex (DLPFC) in terms of both SA and SR conditions. Cortical activity during the CC was not different between the groups. Only in the SAD-group, activity in the pre-motor and supplementary motor cortices, inferior and middle temporal gyri and fronto-polar area was higher during the rejection condition than the other two conditions. Anxiety scores were correlated with activity in STG, DLPFC, FEF and premotor cortex, while avoidance scores were correlated with activity in STG and FEF.
SA and SR are represented differently in terms of cortical activity in SAD subjects compared to healthy controls. Higher activity in both social conditions in SAD subjects compared to controls may imply biological sensitivity to these experiences and may underscore the importance of increased cortical activity during social interaction experiences as a putative mediator of vulnerability to SAD. Higher cortical activity in the SADG may possibly indicate stronger need for inhibitory control mechanisms and higher recruitment of theory of mind functions during social stress. Higher activity during the SR compared to the SA condition in the SAD subjects may also suggest distinct processing of social cues, whether they involve acceptance or rejection.
社交焦虑障碍（SAD）患者的认知和情绪脆弱性，以及他们对重复的社交拒绝和社交接纳体验的反应，是该障碍症状出现和持续存在的重要因素。SAD 的功能神经影像学研究显示，在面对带有负面情绪的人脸时，杏仁核、岛叶、前扣带皮层和前额叶皮层（PFC）等参与恐惧回路的区域会过度活跃。然而，涉及对社交接纳和社交拒绝的标准化人际互动反应的脑活动观察研究仍有所欠缺。
我们比较了一组 SAD 索引受试者（N=22，平均年龄 26.3±5.4，女性/男性比例 7/15）（SADG）与一组健康对照组（CG）（N=21，平均年龄 28.7±4.5，女性/男性比例 14/7）在标准化人际互动体验期间的皮质活动，这些体验涉及由真实演员进行的社交接纳（SA）和社交拒绝（SR）视频模拟握手任务。在第三个对照条件（CC）中，受试者需要在等效空间中按下开关按钮。排除同时出现心境发作的受试者，并控制亚临床抑郁症状的严重程度。使用 52 通道近红外光谱（fNIRS）测量皮质活动。
与健康对照组相比，SAD 受试者在 SA 和 SR 条件下，尤其是在投射到中颞回和额眼运动区（FEF）以及背外侧前额叶皮层（DLPFC）的通道中，活动更高。两组在 CC 期间的皮质活动没有差异。只有在 SAD 组中，在拒绝条件下，运动前皮质和辅助运动皮质、下颞回和中颞回以及额极区的活动高于其他两种条件。焦虑评分与 STG、DLPFC、FEF 和运动前皮质的活动相关，而回避评分与 STG 和 FEF 的活动相关。
与健康对照组相比，SAD 受试者在 SA 和 SR 方面的皮质活动表现不同。与对照组相比，SAD 受试者在两种社交条件下的活动更高，这可能意味着他们对这些体验具有更高的生物学敏感性，并且可能强调在社交互动体验中增加皮质活动作为 SAD 易感性的潜在介导因素的重要性。SADG 中的皮质活动较高，可能表明其对抑制控制机制的需求更强，以及在社交压力下更高的心理理论功能招募。与 SA 相比，SAD 受试者在 SR 条件下的活动更高，这也可能表明他们对社交线索的处理方式不同，无论是接受还是拒绝。
