Altered functional connectivity of the amygdala and its subregions in typhoon-related post-traumatic stress disorder

Background New evidence suggests that the centromedial amygdala (CMA) and the basolateral amygdala (BLA) play different roles in threat processing. Our study aimed to investigate the effects of trauma and post-traumatic stress disorder (PTSD) on the functional connectivity (FC) of the amygdala and its subregions. Methods Twenty-seven patients with typhoon-related PTSD, 33 trauma-exposed controls (TEC), and 30 healthy controls (HC) were scanned with a 3-Tesla magnetic resonance imaging scanner. The FCs of the BLA, the CMA, and the amygdala as a whole were examined using a seed-based approach, and then, the analysis of variance was used to compare the groups. Results We demonstrated that the BLA had a stronger connectivity with the prefrontal cortices (PFCs) and angular gyrus in the PTSD group than in the TEC group. Additionally, compared with the PTSD and the HC groups, the TEC group exhibited decreased and increased BLA FC with the ventromedial PFC and postcentral gyrus (PoCG), respectively. Furthermore, the PTSD group showed abnormal FC between the salience network and default-mode network, as well as the executive control network. Compared with the HC group, the TEC group and the PTSD group both showed decreased BLA FC with the superior temporal gyrus (STG). Finally, the FCs between the bilateral amygdala (as a whole) and the vmPFC, and between the BLA and the vmPFC have a negative correlation with the severity of PTSD. Conclusions Decreased BLA-vmPFC FC and increased BLA-PoCG FC may reflect PTSD resilience factors. Trauma leads to decreased connectivity between the BLA and the STG, which could be further aggravated by PTSD.

Automated summary

The study found that in patients with typhoon-related PTSD, BLA had stronger connectivity with PFC and angular gyrus compared to the TEC group. Additionally, the TEC group showed decreased and increased BLA connectivity with vmPFC and PoCG, respectively, compared to the PTSD and HC groups. The PTSD group exhibited abnormal connectivity between BLA and STG, and connectivity between BLA and vmPFC showed a negative correlation with the severity of PTSD.