title: Environmental Determinants of Aggression in Adolescents: Role of Urban Neighborhood Greenspace.
abstract: Neighborhood greenspace improves mental health of urban-dwelling populations, but its putative neurobehavioral benefits in adolescents remain unclear. We conducted a prospective study on urban-dwelling adolescents to examine the association between greenspace in residential neighborhood and aggressive behaviors.
  
  
  
  Participants (n = 1,287) of the Risk Factors for Antisocial Behavior Study, a multi-ethnic cohort of twins and triplets born in 1990 to 1995 and living in Southern California, were examined in 2000 to 2012 (aged 9-18 years) with repeated assessments of their aggressive behaviors by the parent-reported Child Behavior Checklist. Normalized Difference Vegetation Index (NDVI) derived from satellite imagery was used as a proxy for residential neighborhood greenspace aggregated over various spatiotemporal scales before each assessment. Multilevel mixed-effects models were used to estimate the effects of greenspace on aggressive behaviors, adjusting for within-family/within-individual correlations and other potential confounders.
  
  
  
  Both short-term (1- to 6-month) and long-term (1- to 3-year) exposures to greenspace within 1,000 meters surrounding residences were associated with reduced aggressive behaviors. The benefit of increasing vegetation over the range (∼0.12 in NDVI) commonly seen in urban environments was equivalent to approximately 2 to 2.5 years of behavioral maturation. Sociodemographic factors (e.g., age, gender, race/ethnicity, and socioeconomic status) and neighborhood quality did not confound or modify these associations, and the benefits remained after accounting for temperature.
  
  
  
  Our novel findings support the benefits of neighborhood greenspace in reducing aggressive behaviors of urban-dwelling adolescents. Community-based interventions are needed to determine the efficacy of greenspace as a preemptive strategy to reduce aggressive behaviors in urban environments.
authors.affiliation: Keck School of Medicine of the University of Southern California, Los Angeles. Electronic address: dyounan@usc.edu.
authors.forename: Diana
authors.initials: D
authors.lastname: Younan
authors.affiliation: University of Southern California Dornsife College of Letters, Arts, and Sciences, Los Angeles; School of Law, Psychology and Social Work, Örebro University, Örebro, Sweden.
authors.forename: Catherine
authors.initials: C
authors.lastname: Tuvblad
authors.affiliation: Keck School of Medicine of the University of Southern California, Los Angeles.
authors.forename: Lianfa
authors.initials: L
authors.lastname: Li
authors.affiliation: Program in Public Health, University of California, Irvine College of Health Sciences, Irvine.
authors.forename: Jun
authors.initials: J
authors.lastname: Wu
authors.affiliation: Sonoma Technology, Inc., Petaluma, CA.
authors.forename: Fred
authors.initials: F
authors.lastname: Lurmann
authors.affiliation: Keck School of Medicine of the University of Southern California, Los Angeles.
authors.forename: Meredith
authors.initials: M
authors.lastname: Franklin
authors.affiliation: Keck School of Medicine of the University of Southern California, Los Angeles.
authors.forename: Kiros
authors.initials: K
authors.lastname: Berhane
authors.affiliation: Keck School of Medicine of the University of Southern California, Los Angeles.
authors.forename: Rob
authors.initials: R
authors.lastname: McConnell
authors.affiliation: Keck School of Medicine of the University of Southern California, Los Angeles.
authors.forename: Anna H
authors.initials: AH
authors.lastname: Wu
authors.affiliation: University of Southern California Dornsife College of Letters, Arts, and Sciences, Los Angeles.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Baker
authors.affiliation: Keck School of Medicine of the University of Southern California, Los Angeles.
authors.forename: Jiu-Chiuan
authors.initials: JC
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D000374:Aggression; D002140:California; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D000068316:Parks, Recreational / Q000706:statistics & numerical data*; D012111:Residence Characteristics; D014505:Urban Population
keywords: adolescents; aggression; environment; epidemiology; greenspace