Association between urban upbringing and functional brain connectivity in schizophrenia

Indian Journal of Psychiatry, vol. 66, pp. 71–81

Abstract

Background: Environmental factors considerably influence the development of the human cortex during the perinatal period, early childhood, and adolescence. Urban upbringing in the first 15 years of life is a known risk factor for schizophrenia (SCZ). Though the risk of urban birth and upbringing is well-examined from an epidemiological perspective, the biological mechanisms underlying urban upbringing remain unknown. The effect of urban birth and upbringing on functional brain connectivity in SCZ patients is not yet examined. Methods: This is a secondary data analysis of three studies that included 87 patients with SCZ and 70 healthy volunteers (HV) aged 18 to 50 years. We calculated the developmental urbanicity index using a validated method in earlier studies. Following standard pre-processing of resting functional magnetic resonance imaging (fMRI) scans, seed-return on investment (ROI) functional connectivity analysis was performed. Results: The results showed a significant association between urban birth and upbringing on functional connectivity in SCZ patients and HV ( P < 0.05). In SCZ patients, connections from the right caudate, anterior cingulate cortex, left and right intracalcarine cortices, left and right lingual gyri, left posterior parahippocampal cortex to the cerebellum, fusiform gyri, lateral occipital cortex, and amygdala were significantly associated with the urbanicity index ( P < 0.05). Conclusions: These study findings suggest a significant association between urban birth and upbringing on functional brain connectivity in regions involved in reward processing and social cognition in SCZ. Assessment of social cognition could have implications in developing an in-depth understanding of this impairment in persons with SCZ.

Authors 11

1. Vittal Korann corresponding

   Centre for Addiction and Mental Health · University of Toronto

   Affiliation as printed

   Institute of Medical Science, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada

   Schizophrenia Division, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada

2. Umesh Thonse corresponding

   Manipal Academy of Higher Education · Kasturba Medical College, Manipal

   Affiliation as printed

   Department of Psychiatry, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India

3. Ranjini Garani Ramesh

   Douglas Mental Health University Institute · McGill University

   Affiliation as printed

   Douglas Research Centre, Montreal, Quebec, Canada

   Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada

4. Arpitha Jacob

   National Institute of Mental Health and Neurosciences

   Affiliation as printed

   Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India

5. Shukti Ramkiran Aachen Department of Psychiatry, Psychotherapy and Psychosomatics

   Universitätsklinikum Aachen

   Affiliation as printed

   Department of Psychiatry, Psychotherapy and Psychosomatics, Uniklinik RWTH Aachen, Pauwelsstraße 30, 52074 Aachen, Germany

6. Samir Kumar Praharaj

   Manipal Academy of Higher Education · Kasturba Medical College, Manipal

   Affiliation as printed

   Department of Psychiatry, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India

7. Rose Dawn Bharath

   National Institute of Mental Health and Neurosciences

   Affiliation as printed

   Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India

8. Vijay Kumar

   National Institute of Mental Health and Neurosciences

   Affiliation as printed

   Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India

9. Shivarama S. Varambally

   National Institute of Mental Health and Neurosciences

   Affiliation as printed

   Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India

10. Ganesan Venkatasubramanian

    National Institute of Mental Health and Neurosciences

    Affiliation as printed

    Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India

11. Naren Prahalada Rao

    National Institute of Mental Health and Neurosciences

    Affiliation as printed

    Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India