18 SEP 2026 (FRI) 15:00-15:15
- 3 days ago
- 2 min read
Updated: 3 hours ago
HKU GEOGRAPHY: Monthly Research Talks
Real-Time Physiological and Emotional Responses to the Deadly Tai Po Fire in Hong Kong
Date: 18 SEP 2026 (Friday)
Time: 15:00-15:15 (HKT)
(No registration required)
Abstract:
Research on the mental health impacts of urban traumatic events has mainly relied on retrospective questionnaires. While useful for capturing subjective experiences, these methods are vulnerable to recall bias and cannot detect acute stress responses. This limits knowledge of how traumatic events affect mental health beyond the incident site.
Wearable biosensors combined with GPS offer a methodological alternative by capturing physiological stress responses as people move through changing environments. However, few studies have applied this approach to traumatic events. We use this method to examine indirect stress responses during the November 2025 Tai Po Fire in Hong Kong, the city’s deadliest fire in nearly 80 years, which claimed 168 lives. The fire rapidly changed natural and social environments, with air pollution spreading citywide and news covered on social media.
Following our published protocol, we analyzed 166,114 minute-level electrodermal activity (EDA) records and GPS trajectories from 19 participants, along with 227 daily surveys. PM2.5 and PM10 exposures were estimated at participants’ locations using inverse distance weighting. Mixed-effects models examined pollution-related stress responses during the incident.
Results showed that 42% of participants had significant EDA elevations during the fire period. Stress responses were positively associated with fire-related air pollution. Negative affect increased significantly, while higher screen time was associated with lower positive affect. These findings show the value of integrating biosensors, GPS, and survey data to capture multi-pathway stress responses that traditional methods may overlook. Policies should consider both environmental and digital stressors beyond the incident site in mental health responses.
Professor Yanjia Cao
Assistant Professor, Department of Geography, HKU
