How exactly does schizophrenia start and develop?

Question

What exactly happens in the brain?

In: Biology

Answer 1

We don’t quite know how schizophrenia develops. What we know about is a lot of individual risk factors, and the prevailing scientific theory is that it’s a disorder acquired through one’s development, and that it’s precipitated by certain biological risk factors.

Now, we’re also not too sure about what constitutes as “schizophrenia” proper. Diagnostically, psychotic episodes for a certain period of time not obviously triggered by substance use is enough for a diagnosis of schizophrenia. But psychotic breakdowns can occur in a lot of mental states, and schizophrenic psychoses tend to have a distinct quality as compared to other psychoses.

What we know about the development of schizophrenia is that it tends to develop during a long period before people become ill. The symptoms are very subtle, and for this reason has often gone undetected and the eventual descent into psychosis has appeared sudden and acute. This period before overt schizophrenia is called the “prodromal phase”. This phase typically lasts for years, and is characterized by subtle alterations in subjectivity. That is, the experience of actually being a person.

These alterations are surely very strange and current qualitative research has called these symptoms “self-disorder”, and they are unique to schizophrenia. There is a vast amount of manifestations of this disturbed subjectivity, manifesting in disturbance in the thinking process itself, disturbed self-awareness and presence, strange bodily experiences, issues with being a demarcated subject of experience (for example, a person might look at themselves in the mirror and see a stranger on the opposite end, or wonder at which side of the mirror they are, etc), and existential themes.

One model to collect these experiences is the “ipseity disturbance” model. In this theory, subjective alterations is explained by two core processes–hyperreflexivity (to think excessively about self-evident aspects of our experience) and diminished self-affectivity (to feel one’s self as not quite existing, or only weakly interacting with the world). This eventually develops into full-blown psychotic episodes but the feeling of disturbed subjectivity is reported to linger in between psychotic episodes.