Study: “Community severance” by roads and traffic increases schizophrenia-related hospital admissions

The new framework from Brown University researchers evaluates the impact of urban design elements on mental health disorders separate from pollution-related factors — a first in its field.

2 minute read

April 29, 2026, 9:00 AM PDT

By Christine McLaren


A groundbreaking new study by Brown University researchers has revealed the mental health impacts of "community severance" caused by roadways and traffic patterns, Bioengineer.org reports. Specifically, the study details hospital visits related to mood, anxiety, adjustment, and schizophrenia disorders in New York State, showing significantly increased rates of schizophrenia-related hospital admissions in areas of higher severance across demographic boundaries.

“While previous research has extensively documented the harmful impacts of traffic-related air pollution and noise on psychological well-being, this study uniquely focuses on how the physical fragmentation of neighborhoods by roads and the resultant social isolation affect mental health outcomes, with a particular emphasis on schizophrenia-related hospital visits,” Bioengineer.org reports. 

“Unlike traditional measures of urban pollution and noise, this index captures the extent to which road infrastructure—such as divided highways, lack of sidewalks, and inadequate crosswalks—disrupts pedestrian connectivity and social interactions within communities. This framework allows for an unprecedented evaluation of how urban design elements contribute independently to mental health disorders, separate from pollution-related factors.”

The study details how neighborhood walkability, vibrancy and sociability — all discouraged by severance — impact key protective mental health pillars like social supports, exercise and access to the outdoors. They emphasized the importance of the findings in relation to the transition to electrified vehicles, noting that while EVs reduce emissions and noise pollution, they do not sufficiently mitigate the mental health impacts of car dependency and the loss of community connectivity it brings.

The federally-funded study was supported by the National Institute of Environmental Health Sciences and the National Institute on Aging. It was based on the Community Severance Index, a metric developed initially at Columbia Mailman School of Public Health and refined through collaboration with Brown University experts. 

Read the full story, below.

Monday, April 27, 2026 in Bioengineer.org

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