[PREPRINT] Neural vulnerability and hurricane-related media predict posttraumatic stress in youth

Dick AS, Silva K, Gonzalez R, Sutherland MT, Laird AR, Thompson WK, Tapert SF, Squeglia LM, Gray KM, Nixon SJ, Cottler LB, Le Greca AM, Gurwitch RH, Comer JS, bioRxiv (2020).

Abstract

As natural disasters increase in frequency and severity1,2, mounting evidence reveals that their human toll extends beyond death, injury, and loss. Posttraumatic stress (PTS) can be common among exposed individuals, and children are particularly vulnerable3,4. Curiously, PTS can even be found among youth far removed from harm’s way, and media-based exposure may partially account for this phenomenon5–8. Unfortunately, susceptibility to media effects has been difficult to characterize because most research is initiated post-event, precluding examination of pre-disaster factors. In this study, we mitigate this issue with data from nearly 400 9- to 11-year-old children collected prior to and after Hurricane Irma. We evaluate whether preexisting neural patterns predict degree of media effects on later Irma-related PTS. We show that “dose” of Irma-related media exposure predicted Irma-related PTS–even among children dwelling thousands of kilometers away from the hurricane. Furthermore, we show, using pre-hurricane functional magnetic resonance imaging data, that neural responses in brain regions associated with anxiety and stress confer particular vulnerability to media effects and PTS among certain children. Specifically, right amygdala predicted Irma-related PTS, and bilateral orbitofrontal cortex and right parahippocampal gyrus moderated the association between Irma-related media exposure and PTS. Collectively, these findings run counter to outdated “bullseye” models of disaster exposure that assume negative effects are narrowly circumscribed around a disaster’s geographic epicenter9. In contrast, for some youth with measurable preexisting vulnerability, consumption of extensive disaster-related media appears to offer an alternative pathway to disaster exposure that transcends geography and objective risk. This preventable exposure should be considered in disaster-related mental health efforts.