The term schizophrenia comes from Greek and means "the splitting of the mind", reflecting the disorganised patterns of thinking and the split between emotions and thoughts associated with schizophrenia. While perhaps the most characteristic symptom of schizophrenia is disturbed perception (hallucinations), the condition can also involve disrupted patterns of thoughts, emotions and behaviour.
Schizophrenia can manifest as hallucinations, freepik.com/storyset
What are the symptoms of schizophrenia?
Symptoms associated with schizophrenia are typically grouped into positive and negative symptoms. Positive symptoms refer to symptoms that add an experience for the person, while negative symptoms refer to a lack of an experience, which is typically present.
The least discussed group of symptoms are cognitive symptoms, which refer to cognitive impairments observed in people with a schizophrenia diagnosis.
But before we look at the symptoms in detail, let's consider some of the key statistics related to schizophrenia.
Key statistics of schizophrenia
WHO reports that schizophrenia affects 0.33% of the population worldwide, meaning that 1 in 300 people are affected. In the UK, the prevalence of psychotic disorders is estimated at 0.7%.
The review of Ochoa and colleagues (2012) identified several sex differences related to the prevalence, onset and symptoms of schizophrenia.
The prevalence appears to be higher for men, who also tend to experience earlier onset of schizophrenia.
Women tend to have higher recovery rates with lower rates of relapse compared to men.
Research on sex differences in symptoms is not clear, but it has been suggested that negative symptoms are more common for males. At the same time, females are more likely to experience affective symptoms (symptoms related to mood).
Higher rates of psychosis have been found in ethnic minorities. Some researchers have proposed this is linked to the experiences of discrimination and adversity ethnic minorities are likely to experience.
Studies estimate that around 13.5% of people recover from schizophrenia (Jääskeläinen et al., 2013). The rate of remission is much higher at around 36%. Recovery rates appear to be lower for ethnic minorities. This statistic has been associated with worse clinical service experiences.
Negative Symptoms of Schizophrenia
Some of the main negative symptoms of schizophrenia include flat affect, anhedonia, avolition, asociality and alogia. Not everyone with schizophrenia will experience negative symptoms; some might experience only a few of them.
Negative symptoms of schizophrenia refer to reduced or absent mental functions or behaviours. They take away an experience from the person, in a sense.
Flat affect
One negative symptom is blunted or flat affect, which is an inability to express emotions. People with a flat affect might appear apathetic and express little to no facial expressions that would indicate emotions. Their ability to express emotions verbally might also change, leading to a monotone speech.
Anhedonia
Anhedonia is an inability to experience pleasure; it is also a symptom of mood disorders like depression. People experiencing anhedonia might stop enjoying activities they typically find pleasurable and lose interest in them.
Avolition
Avolition can be defined as a lack of motivation. Experiences of avolition might make it hard for individuals to get things done. Finishing homework, making food or executing any other goal-oriented action might appear incredibly difficult or impossible. One might lose the ability to perform even simple tasks.
Asociality
Asociality refers to a withdrawal from social activities. It can be associated with avolition as one loses motivation to engage in social behaviours or with anhedonia as one stops enjoying social activities.
Alogia
Alogia refers to the poverty of speech; it might manifest as a difficulty in communicating or maintaining conversations. A person might only give brief responses that lack content. Alogia has been associated with a disruption in thought.
Positive Symptoms of Schizophrenia
Some of the main positive symptoms of schizophrenia include hallucinations, delusions, catatonia, and thought disorder.
Positive symptoms of schizophrenia involve an added aspect of mental and behavioural functioning, which is not typically experienced by a healthy population. They include distorted perceptions (hallucinations) and thoughts (delusions).
Hallucinations Symptoms of Schizophrenia
Hallucinations are perceptions that seem real but are not based on actual external stimuli. Visual hallucinations involve seeing things that aren't really there, and perhaps more common auditory hallucinations involve hearing voices or sounds that are not based on reality.
Other types of hallucinations involve olfactory hallucinations, involving smells or tactile hallucinations, involving touch.
Hearing voices is not always distressing to a person with schizophrenia; sometimes, voices might be helpful or encouraging. Unfortunately, sometimes they can be difficult to deal with and can affect one's daily functioning and wellbeing.
Hearing voices can also be experienced by people in the general population; a systematic review found the median prevalence of hearing voices reported by studies of the general population to be around 13% (Beavan et al 2011).
Delusions
Delusions are ‘false beliefs’ that people hold with great conviction. Different types of delusions include grandiose delusions, persecutory delusions and paranoid delusions.
Grandiose delusions involve holding a grandiose self-image; one may strongly believe they are much more powerful, superior, intelligent or important than others in some way.
People experiencing delusions of grandeur might be convinced they are someone much more powerful or are on a powerful mission, for example, believing they are the next Einstein or a member of the royal family.
Persecutory delusions involve distorted beliefs about the motives of others. People may become convinced others are trying to harm them, act suspicious of or hostile towards the people they don't trust, or engage in irrational behaviour like destroying their phone because of a fear of being tracked.
Paranoid delusions are a symptom of schizophrenia in some cases, freepik.comCatatonia
Catatonia refers to abnormal/lack of movements. It may involve agitated movements or decreased consciousness and, therefore, a diminished ability to respond to external stimuli. Catatonic behaviour may involve staying in the same position for extended amounts of time, lack of speech and movement or slow movements.
Thought disorder
Experiencing disordered thoughts may result in difficulty understanding or communicating one's thoughts. One's thoughts may seem fragmented or illogical. Thought disorder often results in disordered speech, which occurs when the words expressed by a person do not appear to be connected in any meaningful way.
Cognitive Symptoms of Schizophrenia
Cognitive symptoms of schizophrenia involve impaired executive functioning, including difficulties with learning, storing and manipulating information. These symptoms may negatively affect a person's ability to perform goal-oriented actions or respond to situations.
An inability to perform goal-oriented behaviour is associated with schizophrenia, flaticon.com
Disorganised and slow thinking is also considered cognitive symptoms of schizophrenia; difficulties with thinking may also result in a person developing a belief that their thoughts are being taken out or put into their heads (thought withdrawal or thought insertion).
Other cognitive symptoms are impaired attention and diminished ability to concentrate on a single stimulus and diminished ability to plan future tasks.
Cognitive impairments in schizophrenia may also reinforce anosognosia or a lack of understanding of one's illness. Anosognosia involves an inability to perceive and recognise that one is experiencing symptoms of a mental disorder.
Early Symptoms of Schizophrenia
The onset of schizophrenia is associated with young adulthood, with the first symptoms typically presenting in one's late adolescence or 20s. Three main stages of schizophrenia development have been identified, prodromal, active, and residual stages, which differ in terms of the severity of psychotic symptoms.
Symptoms characteristic of the early, prodromal stage of schizophrenia involve:
- Negative symptoms like social withdrawal, avolition, alogia, flat affect, lack of energy,
- The onset of positive symptoms like distorted beliefs or abnormal perceptual experiences, a person may begin to experience a loss of contact with reality,
- Impaired functioning,
- Abnormal behaviour.
Since many symptoms associated with schizophrenia are also common in other psychiatric conditions, it may be difficult to reach a definite diagnosis, especially at an early stage. That is why it is important to seek a diagnosis from a professional that will be able to make a differential diagnosis, meaning exclude other conditions that may share symptoms with schizophrenia.
We talk about symptom overlap when the same symptoms are shared across different psychiatric conditions. For example, both depression and schizophrenia might share some of the negative symptoms, while positive symptoms are also associated with bipolar disorder.
Symptoms of Schizophrenia - Key takeaways
- Symptoms of schizophrenia can be grouped into positive, negative and cognitive symptoms.
- Negative symptoms of schizophrenia refer to reduced or absent mental functions or behaviours, including flat affect, anhedonia, avolition, asociality and alogia.
- Positive symptoms of schizophrenia involve an added aspect of mental and behavioural functioning, which is not typically experienced by a healthy population. They include distorted perceptions (hallucinations) and thoughts (delusions), thought disorders, and catatonic behaviour.
- Disordered thoughts, impaired concentration and executive functioning are the cognitive symptoms of schizophrenia.
- The onset of schizophrenia typically occurs in young adulthood. The early symptoms to look for are negative symptoms and the initial psychotic experiences, including unusual delusions and hallucinations.
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