Beyond direct trauma: Vicarious exposure, media-induced stress, and external stress overload as emerging public mental health challenges

Table 1 Summary of included studies on indirect threat exposure, media-induced stress, and psychological outcomes

Ref.	Design	Population	Exposure	Outcomes	Key findings	Relevance to model
Lisa Mccann and Pearlman[1]	Conceptual	Clinicians	Indirect trauma exposure	Psychological impact	Introduced the vicarious trauma framework	Foundational for indirect exposure
Figley[2]	Conceptual	Care providers	Secondary trauma	Emotional fatigue	Defined compassion fatigue	Theoretical basis
Pfefferbaum and North[3]	Narrative review	General population	Pandemic stress	Anxiety; distress	Described widespread mental health burden during the pandemic	Population-level context
Holman et al[4]	Longitudinal	United States adults	Media exposure after Boston Marathon bombing	Acute stress	Higher media exposure was associated with greater stress; in some cases exceeding direct exposure	Core evidence
Holman et al[5]	Longitudinal	Adults	Trauma-related media	Mental health; functioning	Media exposure predicted distress and functional impairment	Core evidence
Silver et al[6]	Longitudinal	United States population	9/11 media exposure	PTSD symptoms; distress	Showed persistent psychological effects across the population	Core evidence
Pfefferbaum et al[7]	Systematic review	Mixed populations	Disaster media exposure	Psychological outcomes	Reported a consistent link between disaster media exposure and distress	Meta-level support
Garfin et al[15]	Conceptual review	General population	COVID-19 media exposure	Stress; anxiety	Proposed that media exposure may amplify public health consequences	Conceptual bridge
Racine et al[16]	Meta-analysis	Children and adolescents	Pandemic-related stress	Anxiety; depression	Reported increased prevalence of depressive and anxiety symptoms	Vulnerability subgroup
World Health Organization[8]	Policy report	Global population	Infodemic exposure	Distress	Highlighted potential harm from information overload and misinformation	Infodemic concept
Gao et al[9]	Cross-sectional	Chinese population	Social media exposure	Anxiety; depression	High social media exposure was linked to poorer mental health	Modern empirical support
Bendau et al[10]	Cross-sectional	Adults	COVID-19 media consumption	Anxiety; depression	Media use correlated with symptoms of anxiety, depression, and COVID-related fear	Strong modern evidence
Olagoke et al[11]	Cross-sectional	Adults	News exposure	Depression; risk perception	Exposure to coronavirus news was associated with higher distress	Supports exposure effect
Satici et al[12]	Mediation analysis	Adults	Uncertainty	Anxiety; wellbeing	Intolerance of uncertainty and rumination mediated distress	Mechanism: Uncertainty
Garfin et al[22]	Systematic review	Mixed populations	Acute stress exposure	Health outcomes	Acute stress predicted later health outcomes	Stress pathway
McEwen[18]	Review	General	Stress	Neurobiological impact	Described allostatic load as a cumulative biological burden	Biological plausibility
Arnsten[19]	Review	Neurobiology	Stress	Prefrontal cortex dysfunction	Stress impairs prefrontal/executive control	Mechanism
LeDoux[20]	Review	Neurobiology	Threat processing	Emotional circuits	Described amygdala-based threat processing	Mechanism
Chao et al[13]	Cross-sectional	General population	COVID-19 media exposure	Anxiety; stress	Media use was linked to acute psychological outcomes	Strong synthesis
Thompson et al[17]	Cross-sectional	United States adults	Ebola media exposure	Distress; worry	Media exposure predicted distress during a global health crisis	Population evidence
Buchanan et al[14]	Experimental	Adults	Doomscrolling vs positive content	Affect; optimism	Negative content produced immediate emotional decline; positive content did not	Mechanistic support

Studies were selected for their relevance to indirect threat exposure, media-induced stress, crisis-related information exposure, cognitive and behavioral mechanisms, and biological plausibility within the external stress overload framework. PTSD: Post-traumatic stress disorder; COVID-19: Coronavirus disease 2019.