Subtitles section Play video Print subtitles We all have an inner dialogue inside our mind - reminding yourself to pay your cellphone bill, or even rehearsing a tough conversation with a friend. But what if that voice becomes voices that are out of your control? Psychologist Julian Jaynes proposed a theory that, not so long ago all humans heard voices - created internally from the right hemisphere of the brain, but perceived as external from the left hemisphere (bicameralism). As a result these voices were perceived as communication from the gods. But around 1000 BC, with the rise of modern consciousness, these voices became recognized as our own. Some psychiatrists believe that the brains of schizophrenic people may revert to this state, and not recognize some of their thoughts as their own. Schizophrenia is a disease of the nervous system, affecting approximately 1% of the population. To be clear, schizophrenia is not the same as having ‘multiple personality disorder’. Symptoms often include hallucinations: from seeing things that aren’t there, to delusions such as a higher belief in conspiracy, higher rates of depression, and most notably hearing voices. Auditory hallucinations occur in many disorders - from simple sounds to words or names being called - but the voices heard in schizophrenics are quite different. They are often associated with their current mental state, and can be quite hostile, accusing, threatening or persecuting (58); ultimately embodying many of their fears. A 2006 study of over 3000 schizophrenic patients found that genes related to immune function may play a role - specifically the complement component 4 or C4 genes. C4 is a gene involved in trimming the synapses in the brain; for example, teenage brains undergo a process known as ‘synaptic pruning’ in which unused connections are cut away to aid in our brains efficiency. But in individuals with schizophrenia, this C4 gene may be overactive and cut down areas that are involved in planning, cognition and thinking. Links have also made between microbes in the gut - after all, the microbes that live within us have also been shown to modulate immune response and impact brain development. One study found that lactic acid bacteria were significantly more abundant in people with schizophrenia, while another found that the prevalence of lipid and glucose abnormalities is much higher in patients with schizophrenia. And while diagnosing schizophrenia is primarily based on behavior and reported experiences, research has found the cause to be a combination of these genetic factors along with some environmental stressors like growing up in an urbanized area, minority group position, and even cannabis use as THC can exaggerate psychotic response in some individuals with genetic risk or developmental trauma. Currently, medication for schizophrenia mostly focuses on combating hallucinations and delusions but, unfortunately, 49.5% of schizophrenia patients don’t end up taking their medicine. This is why genetic research is so important to combatting this disease. Of course, some people can and do recover through a combination of medication, counselling and support which can greatly reduce the symptoms. On AsapTHOUGHT we talk about how mental health stigma is a serious issue in our culture and the media. Many of us negatively contribute to the stereotyping of mental illness without even realizing it - so we break down 5 ways we can all reduce mental health stigma right now. Check it out with the link below. And special thanks to audible for supporting this episode to give you a free 30 day trial at audible.com/asap. This week we wanted to recommend the book “Schizophrenia: Understanding Symptoms Diagnosis & Treatment” which tackles much of the stigma tied to schizophrenia and how it affects those with the condition. You can get a free 30 day trial at audible.com/asap and choose from a massive selection! We love them as they are great when you’re on the go. And subscribe for more weekly science videos!