title: The relationship between natural outdoor environments and cognitive functioning and its mediators.
abstract: Urban residents may experience cognitive fatigue and little opportunity for mental restoration due to a lack of access to nature. Natural outdoor environments (NOE) are thought to be beneficial for cognitive functioning, but underlying mechanisms are not clear.
  
  
  
  To investigate the long-term association between NOE and cognitive function, and its potential mediators.
  
  
  
  This cross-sectional study was based on adult participants of the Positive Health Effects of the Natural Outdoor Environment in Typical Populations in Different Regions in Europe (PHENOTYPE) project. Data were collected in Barcelona, Spain; Doetinchem, the Netherlands; and Stoke-on-Trent, United Kingdom. We assessed residential distance to NOE, residential surrounding greenness, perceived amount of neighborhood NOE, and engagement with NOE. Cognitive function was assessed with the Color Trails Test (CTT). Mediation analysis was undertaken following Baron and Kenny.
  
  
  
  Each 100m increase in residential distance to NOE was associated with a longer CTT completion time of 1.50% (95% CI 0.13, 2.89). No associations were found for other NOE indicators and cognitive function. Neighborhood social cohesion was (marginally) significantly associated with both residential distance to NOE and CTT completion time, but no evidence for mediation was found. Nor were there indications for mediation by physical activity, social interaction with neighbors, loneliness, mental health, air pollution worries, or noise annoyance.
  
  
  
  Our findings provide some indication that proximity to nature may benefit cognitive function. We could not establish which mechanisms may explain this relationship.
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain. Electronic address: wilma.zijlema@isglobal.org.
authors.forename: Wilma L
authors.initials: WL
authors.lastname: Zijlema
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain.
authors.forename: Margarita
authors.initials: M
authors.lastname: Triguero-Mas
authors.affiliation: Staffordshire University, Leek Road, Stoke-on-Trent ST4 2DF, UK.
authors.forename: Graham
authors.initials: G
authors.lastname: Smith
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Cirach
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Martinez
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain.
authors.forename: Payam
authors.initials: P
authors.lastname: Dadvand
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain.
authors.forename: Mireia
authors.initials: M
authors.lastname: Gascon
authors.affiliation: Staffordshire University, Leek Road, Stoke-on-Trent ST4 2DF, UK.
authors.forename: Marc
authors.initials: M
authors.lastname: Jones
authors.affiliation: Staffordshire University, Leek Road, Stoke-on-Trent ST4 2DF, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Gidlow
authors.affiliation: Staffordshire University, Leek Road, Stoke-on-Trent ST4 2DF, UK.
authors.forename: Gemma
authors.initials: G
authors.lastname: Hurst
authors.affiliation: Staffordshire University, Leek Road, Stoke-on-Trent ST4 2DF, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Masterson
authors.affiliation: Staffordshire University, Leek Road, Stoke-on-Trent ST4 2DF, UK.
authors.forename: Naomi
authors.initials: N
authors.lastname: Ellis
authors.affiliation: Department of Public & Occupational Health and EMGO Institute for Health and Care research, VU University Medical Center, De Boelelaan 1105, 1081 HV Amsterdam, The Netherlands.
authors.forename: Magdalena
authors.initials: M
authors.lastname: van den Berg
authors.affiliation: Department of Clinical, Neuro and Developmental Psychology, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081 HV Amsterdam, The Netherlands.
authors.forename: Jolanda
authors.initials: J
authors.lastname: Maas
authors.affiliation: RIVM, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands.
authors.forename: Irene
authors.initials: I
authors.lastname: van Kamp
authors.affiliation: VGGM, Eusebiusbuitensingel 43, 6828 HZ Arnhem, The Netherlands.
authors.forename: Peter
authors.initials: P
authors.lastname: van den Hazel
authors.affiliation: RIVM, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands.
authors.forename: Hanneke
authors.initials: H
authors.lastname: Kruize
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Nieuwenhuijsen
authors.affiliation: Barcelona Institute for Global Health (ISGlobal), Doctor Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Doctor Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029 Madrid, Spain. Electronic address: jordi.julvez@isglobal.org.
authors.forename: Jordi
authors.initials: J
authors.lastname: Julvez
mesh_terms: D000328:Adult; D000368:Aged; D000397:Air Pollution; D002947:Cities; D003071:Cognition; D004777:Environment; D015444:Exercise; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008132:Loneliness; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D009426:Netherlands; D009622:Noise; D013030:Spain; D006113:United Kingdom; D055815:Young Adult
keywords: Built environment; Cognition; Environmental epidemiology; Green space; Mediation; Natural outdoor environments