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

Young Professional

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban and Environmental Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban and Environmental Planner

Get top-rated, practical training for planners

"Planetizen federal action tracker" logo superimposed over black and white image of US Capitol dome.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

October 28, 2026 - Zachary Whalen

A car drives through a puddle, making a large splash. Rain pours down.

California plans to bury El Niño’s downpour

If the state plays its cards right, it may be able to store a billion acre-feet of El Niño’s water in aquifers.

October 28, 2026 - Grist

Lake Powell with much of the water evaporated.

Desperate measures: Advocates weigh draining Lake Powell to fill Colorado River

Draining the reservoir could reduce evaporation losses by a couple hundred thousand acre-feet.

October 30, 2026 - Yale Environment 360

The Chicago Avenue Bridge when it was open, a dark red bridge in front of downtown.

Chicago Avenue bridge construction delays enrages city leaders

The bridge has been closed since 2025. The city originally aimed to re-open it in December, and now expects to finish construction in 2027.

November 1 - Block Club Chicago

People walk to a bus in Queens

NYC bus network redesign speeds up Queens buses

Rush routes have seen a 4.6% speed increase after the redesign.

November 1 - Mass Transit

A rendering of the California high speed rail Fresno station. Two escalators leading into the station are visible.

California High-Speed Rail Authority picks trainset manufacturer

The California High-Speed Rail Authority aims to start servicing passengers by 2033.

November 1 - Railway News