Psychiatry and Society

Is schizophrenia bound to human evolution? Schizophrenia is a neuro-developmental disorder characterised by delusions, hallucinations, and bizarre behaviours. No other animal displays these symptoms. Depression, addiction, anxiety are all found in other animal species, but not schizophrenia. Schizophrenia is not even found in chimpanzees our most recent evolutionary ancestors. It is inheritable, and highly disadvantageous to survival of the affected person. Given this, schizophrenia should be almost non-existent. Yet it continues to affect a massive 1% of the global population. Something is pushing for the persistence of this disorder and its spontaneous manifestation in humans. Human evolution separated from the chimpanzees 5.5 million years ago when we walked upright and then acquired language abilities. Language ability developed after 'lateralisation', the separation of brain functions into the left (sequential) and right (parallel processing) hemispheres. The pecu...

Last week I gave a talk on Personality and Sexuality. One question that cropped up was - "How do I know if my partner is cheating on me?" By chance the next morning there was a newspaper article attributing uncommitted sex, one-night stands, and acts of infidelity to genetics. Individuals who have frequent sex with multiple partners are psychologically different from those who have frequent sex with single partner (Simpson & Gangestad, 1991). This sociosexual difference places individuals in two groups Unrestricted sociosexual types , have a higher number of sexual partners, and one night stands. They have a permissive attitude to casual and uncommitted sex. Restricted sociosexual types , require greater closeness and commitment before sex with their romantic partner.   Genetics plays an important role in sociosexuality Genes evolve to enhance survival of the species. From an evolutionary viewpoint females reproduce with a mate who will invest in ...