Schizophrenia: What is it, Symptoms & Causes
About 1 in 100 people will receive a schizophrenia diagnosis in their lifetime. Despite the growing amount of research, there is still a lot still not understood about schizophrenia, or hearing voices, how people with lived experience may prefer to describe it.
This blog post aims to explain a bit more about what schizophrenia is, outline some of the symptoms of schizophrenia and discuss the researched contributors for the development of schizophrenia, genetics and the environment (aka someone's experiences). First tings first, what is schizophrenia?
What is schizophrenia?
Schizophrenia is a complicated mental health condition, but simply put, it changes how a person perceives and interacts with the world. It affects how a person may think, feel and behave and is usually characterised by the individual experiencing psychosis, where someone interprets reality differently from others.
Psychosis involves hallucinations, delusions, paranoia, disordered thinking and behaviour, which are some of the "positive symptoms" of schizophrenia. Someone may experience psychosis as an episode or as part of another mental health condition, while someone has to be reviewed by a psychiatrist for an extended period of time to be diagnosed with schizophrenia.
This YouTube video, What Schizophrenia Feels Like, shows what one individual's experience of hallucinations looks and sounds like.
'I've heard voices since I was young. They get worse if I'm worried about something or if something bad happens. I usually hear the same voice but sometimes random voices shout things. It makes it difficult to sleep or concentrate. I find that listening to music or watching TV sometimes helps. I didn't tell anyone about the voices for a long time. As time went on I decided to speak to people about the voices. This helped me to accept what was happening.'
Stevie's story, featured on Rethink.org
Symptoms of schizophrenia
Schizophrenia symptoms are divided into negative, positive and cognitive symptoms. Negative and cognitive symptoms may be present in other mental health concerns, whilst the positive symptoms are used in a diagnosis of schizophrenia to confirm psychosis is present for the individual.
It's important to note each person's experience is unique, with symptoms occurring suddenly, or gradually developing over time. Many people who have schizophrenia or hear voices don't find their functional capacity, enjoyment of life or participation in the community negatively impacted by their condition. However, for many people, experiencing these symptoms can make day-to-day functioning quite difficult.
The World Health Organisation says schizophrenia and psychosis is associated with considerable disability and human rights violations both inside mental health institutions and in community settings.
'Stigma against people with this condition is intense and widespread, causing social exclusion, and impacting their relationships with others, including family and friends. This contributes to discrimination, which in turn can limit access to general health care, education, housing, and employment.’
Negative symptoms:
Disorganised thinking and behaviour (seeming bizarre or purposeless)
Apathy and flat emotion, seemingly unable to experience pleasure
Difficulty engaging with people socially
Experiencing a regular lack of motivation
Issues with sleeping
Speech that sounds confused
Extreme agitation or slowing of movements, maintenance of unusual postures
Positive symptoms:
Hallucinations: hearing voices, seeing, smelling or feeling things that aren't there
Delusions: strong beliefs or paranoia not based in reality (believing something is true, even when it can be proven otherwise)
Experiences of influence, control or passivity: experiencing that your feelings, impulses, actions, or thoughts are not yours but put/removed from your mind by something else or that your thoughts are broadcast to others
Cognitive symptoms
Difficulty with attention
Unable to apply information to make decisions
Struggling with reasoning and problem-solving
Impacted working memory
Differences in sensory perception
Processing "social cues"
Expressing vigilance
What causes schizophrenia?
There is a lot of research on the link between genetics and schizophrenia, with studies finding the genetic basis of schizophrenia to be tremendously complex. No single gene is thought to be responsible, it's more likely a combination of genetic mutations that may make people more vulnerable to the condition.
Historically, psychotic illnesses, especially schizophrenia, were viewed as degenerative biological diseases with a poor prognosis in both symptoms and social functioning. From the Australian Institute of Family Studies:
‘As a consequence of these views, treatment of psychoses has largely focused on biological interventions, with a focus on management rather than recovery. More recently, however, it has become clear that environmental factors play an important part in the ætiology [causation] and maintenance of psychotic disorders.'
Genetic factors
Without delving too much into the science of genomics, evidence that schizophrenia is partly inherited comes from studies of twins, as identical twins share the same genes. In identical twins, if one develops schizophrenia, the other has a 1 in 2 chance of developing it, which is still proven true even if they're raised separately.
In non-identical twins, who have different genetic make-ups, when a twin develops schizophrenia, the other has a 1 in 8 chance of developing the condition, higher than in the general population, where the chance is about 1 in 100 chance of someone developing schizophrenia.
A more recent study was the first of its kind to investigate schizophrenia risk across more diverse populations included 35,828 cases with 107,877 controls and flagged two genes, SRRM2 and AKAP11, as "risk genes." Lead author Dongjing Liu says 'by focusing on a subset of genes, we discovered rare damaging variants that could potentially lead to new medicines for schizophrenia.'
A third gene flagged in the study, PCLO, has been previously implicated in schizophrenia, but is now identified as having a shared risk factor for schizophrenia and autism.
'It's been known that there are genetic components shared among illnesses… The same variant in the same family may cause autism in one family member and schizophrenia in another,' says Dr Charney a co-senior corresponding author of the study.
The researchers caution that not every patient has a rare variant in the identified schizophrenia genes, emphasising that schizophrenia is multifactorial and there is no single factor that causes it.
Research has long noted that certain conditions tend to run in families, partly because of genetics and environmental factors such as shared upbringing. Whilst having a first degree relative increases the risk of someone developing schizophrenia, still 85% of individuals with schizophrenia have no immediate family history of schizophrenia.
'No one psychiatric or mental disorder has a full 100% genetic basis or heritability, and many environmental factors may strongly influence the likelihood of developing a particular disorder or not – despite the presence or absence of genetic elements. Many of these disorders, therefore, have multifactorial causes – some genetic and some environmental.'
Environmental factors
This 2016 article There are no "schizophrenia genes": here's why says genetic theories of schizophrenia were popular in the early twentieth century as theories built on concepts of eugenics assuming a "tainted" gene pool underpins all forms of physical or psychological deviance. Professors Richard Bentall and David Pilgrim note in their article,
'That early work, which was reinforced by that of eminent eugenicist psychiatrists, such as Franz Kallmann and Eliot Slater after World War Two, led ultimately to large estimates of the "heritability" of schizophrenia, typically around 80%, which were assumed to leave little room for social causes of the disorder.'
The way we think about schizophrenia today is vastly different from these early understandings, as now we know the impact of our environment and experiences in developing mental health conditions.
The Voices in My Head is a TED Talk by voice hearer Dr Eleanor Longden. In it, she explains that the voices in her head are a meaningful response to traumatic life events, particularly childhood trauma. She argues that the critical question in psychiatry shouldn't be what's wrong with you but what's happened to you.
She says the most significant revelation was interpreting the voices she heard into a metaphorical meaning rather than interpreting them as a literal truth. For example, she learned to interpret voices that threatened to attack her home as a sense of fear and insecurity in the world rather than an actual, objective danger. She says 'what I came to realise was that each voice was closely related to aspects of myself, and that each of them carried overwhelming emotions that I'd never had an opportunity to process or resolve.'
What sort of environmental experiences are identified as schizophrenia risk factors?
Like with many other mental health conditions, research continues to highlight adverse experiences, particularly in childhood, as an increased risk of developing psychotic conditions like schizophrenia.
According to Non-Genetic Factors in Schizophrenia:
'Research has shown pregnancy and birth complications, childhood trauma, migration, social isolation, urbanity, and substance abuse, alone and in combination, acting at a number of levels over time, influence the individual's likelihood to develop the disorder.'
Childhood adversity (defined as sexual abuse, physical abuse, emotional/psychological abuse, neglect, parental death, and bullying) was associated with increased risk for psychosis in adulthood. The analysis noted a "robust link" between childhood trauma and schizophrenia, with 'childhood trauma being associated with the most severe forms of positive symptomatology in adulthood, particularly hallucinations and affective symptoms.'
A recent study to explore the potential role of plasma oxytocin as a mediator in the relationship between childhood trauma and the psychopathology of schizophrenia noted:
'Patients with schizophrenia who experienced childhood trauma are typically younger age at schizophrenia onset (1,2), have worse psychotic symptoms (3,4) have more severe functional impairment (5,6) respond to treatment more poorly (7) and have an even higher risk of suicide (8) than those who did not experience childhood trauma.'
In this study, 160 patients with schizophrenia and 80 matched controls were interviewed for childhood trauma through the childhood trauma questionnaire and structured interviews. Results showed that patients with schizophrenia had higher childhood trauma scores than the other controls.
'Evidence suggests that certain neurobiological processes occur in the brain after trauma. The inflammation and dysregulation from oxidative stress predispose patients to an at-risk-mental state, facilitating the progression to schizophrenia.’
When examining the evidence of a relationship between childhood trauma or adverse life events and psychosis, especially in schizophrenia, researchers found in developmental years, exposure to neglect and abuse reveals severe adverse effects on the average neurobiological growth. They said childhood trauma is probably the most important environmental factor associated with schizophrenia, and encouraged further evaluation of early trauma detection and benefits of early intervention.
We highlighted childhood trauma as an important risk factor in developing schizophrenia, but as noted above, there are many other potential environmental risk factors identified in the development of schizophrenia and hearing voices, like birth and pregnancy complications, migration, social isolation and drug use, particularly cannabis use (although it's not clear if using drugs directly causes symptoms in people who are susceptible to schizophrenia, or if they are more likely to use drugs).
With more understanding of the causation of these conditions, the more practitioners can implement trauma-informed care in settings for people who identify with schizophrenia or hearing voices. For more information and support for people who hear voices, see visions or have other unusual perceptions, check out:
We also have more information on What is a psychosocial disability? (when someone’s mental health condition is negatively impacted by factors in their society) how Psychosocial Disabilities & the NDIS interact. If you or someone you know could benefit from a Psychosocial Functional Capacity Assessment, please don’t hesitate to reach out to us with any enquiries.