While the insula was not an a priori ROI in the current study, expansive α deficits spanning the posterior and anterior insula emerged in PTSD following whole-brain correction. The insula is a highly heterogeneous structure, with the posterior portion receiving strong sensory afferents and the anterior portion densely connected with limbic and prefrontal regions as a key node of the salience network/SN (Craig, 2002; Critchley, 2004; Seeley et al., 2007; Menon and Uddin, 2010). Abnormal insular and SN activity has been repeatedly observed in patients with PTSD (Lanius et al., 2015; Koch et al., 2016), and α suppression via neurofeedback can increase SN activity (Ros et al., 2013). Our data provide preliminary evidence of insular α dysrhythmia in PTSD, potentially underlying some of the insular anomalies. Interestingly, our exploratory whole-brain connectivity analyses further isolated an additional region, the right superior temporal gyrus, showing attenuated connectivity with the DMN (i.e., PCC) in PTSD. This area represents the associative auditory cortex and a primary source of auditory α (“tau”) oscillations (Lehtelä et al., 1997; Billig et al., 2019). This finding thus further
