Cyclists can feel safe at the very moment they are most at risk, according to new Monash research that could reshape how cities design shared streets.
The study found that after a vehicle overtakes a cyclist, riders often experience a short "perceptual relief period" where they feel safer, even though the risk from vehicles behind them remains high.
The study analysed 72 cyclists riding a fixed-base bicycle simulator, using immersive virtual reality and real-time brain monitoring to track how they responded to changing traffic situations as they unfolded.
By synchronising brain activity, traffic simulation data and built environment features, the team identified moments where perception and actual risk diverged.
At the same time, researchers calculated "time-to-collision" (TTC), estimating how long it would take for a vehicle to collide with a cyclist if neither changed speed or direction.
Lead author Lurong Xu, a PhD Candidate at the Department of Civil and Environmental Engineering, said this mismatch between perceived safety and actual crash risk could create a hidden window of danger on mixed-traffic streets.
"Cyclists often feel relieved once a car has passed them. But our data shows the objective risk from following vehicles behind them can still be significant during that moment," Ms Xu said.
The findings also showed that places with lots of greenery, highly detailed building structures, or areas that feel enclosed were more likely to increase the difference between how safe cyclists felt and how much risk they were actually facing.
"Trees, enclosed streets and visually rich surroundings can make a street feel calm and inviting. But in high-risk spots where cyclists and cars are in close interaction, those same features can create a false sense of security, lowering alertness and masking real risks from nearby vehicles," Ms Xu said.
While the experimental street layout was based on a real-world setting in China, the researchers say the underlying principles could be relevant among cities globally, including in Australian cities where cyclists frequently share roads with cars.
"The core takeaway is that feeling safe is not the same as being safe. This is a universal pattern rooted in how the human brain processes risk, which we captured through precise data," Ms Xu said.
"These insights have value for urban environments globally where cyclists and drivers share space because they're based on human biology, but this isn't a one-size-fits-all solution.
"Perceptions of safety are shaped by local street design, geography and driving culture. But the principles we identified can help cities ask better questions about how streets are experienced in real time."
Ms Xu said the findings point to the value of closer collaboration between transport engineering, urban design and neuroscience.
"Our study offers a new lens for understanding cycling safety," Ms Xu said.
"While the results shouldn't be treated as a blueprint for any one city, they highlight the importance of paying attention to how streets feel as well as how they function."
Read the research paper: https://doi.org/10.1016/j.aap.2026.108418
