Cognitive Models And Their Accountability For Diverse Psychosis Symptoms

The term ‘psychosis’ is one that has been associated with a variety of different processes and behaviours amongst the years. More is constantly being learned, and something that used to be associated with supernatural causes, and subsequently simply as result of physical trauma and bodily malfunctions is now identified and treated much more clearly with new theories in many different areas of psychology. Psychosis, as defined by the National Institute of Mental Health, is “ used to describe conditions that affect the mind, where there has been some loss of contact with reality”. It is considered an abnormal condition, which does not have clear, defined causes, but rather many different causal pathways that can lead to psychosis symptoms and psychotic disorders. Different causes can lead to different symptoms, and all vary amongst each individual who experiences it. Symptoms can be divided into different categories, such as positive, negative, and disorganized. Delusions are a positive symptom, and they are the only symptom that is a defining characteristic of psychosis. Positive symptoms, and therefore delusions, are symptoms that add. Delusions are “ fixed beliefs that are not amenable to change in light of conflicting evidence”, that have the characteristics of certainty, incorrigibility and impossibility/falsity. Hallucinations are also positive symptoms, and can range from auditory, visual, tactile and gustatory, though auditory is more common. Negative symptoms take away, such as reduced motivation, inability to show emotions and emotional blunting. Disorganized symptoms relate to disorganized speech, thought and behaviour. These are also referred to as formal thought disorders, which are “disruptions in the form or structure of thinking” (American Psychological Association, 2007). Different cognitive and neurocognitive models focus on the causes and maintenance of these symptoms, in relation to cognitive and neural processes.

Cognitive behavioural models theorise that people’s perception of events influences their emotions and behaviours, therefore the way they perceive a situation is what impacts their thought processes, rather than the situation itself. Neurocognitive models additionally make references to biological processes or the brain, which is not a fundamental feature of cognitive models. Mainly cognitive and neurocognitive models are being applied and developed to assess and treat psychosis. Despite their often effective widespread application, the diversity and variability of psychosis symptoms raises the question of the extent to which cognitive models can account for them. The Aberrant Salience Model of Psychosis mainly focuses on delusions and hallucinations, and other symptoms that occur in relation to the aforementioned ones. It is a neurocognitive model that implies dopamine dysregulation in the brain causes psychotic symptoms, but that treating these symptoms with antipsychotic medication and resolving the neurochemical abnormalities in the brain is not enough to resolve the problem. Despite the significant correlation between dopamine regulation and psychotic symptoms, when medication is administered, can reduce the driving force behind some symptoms, however in severe or long-term cases, these behaviours and symptoms have already been incorporated into larger cognitive schemas. Therefore, medication will only alleviate the drive to a certain extent, however as long as the previously formed schemas remain, it will not be an effective treatment. Although this model has observed an association between dopamine dysregulation and positive psychotic symptoms, it cannot clearly explain causality between them. Other cognitive models include predictive coding models for psychosis. These models theorize that cognition is comprised of predictive coding feedback loops, which are based on Bayesian principles. Prior beliefs are tested against an outcome in order to make inferences about their current environment. Errors between prior beliefs and predicted outcome sensory signals lead to updated predictions, which drive new learning. 

Psychosis is seen as a dysfunction to this system. One of the predictive coding models suggests that when prediction errors are made from the difference between prior beliefs and the outcome, normally new learning would be driven more by prior beliefs, rather than the new sensory data of the outcome. They relate psychosis to the imbalance in precision driving interference and new predictions more to sensory data, rather than prior belief (Sterzer et al., 2018). This model also theorizes on possible causes of hallucinations and delusions, however as a result of dysfunctional predictive coding, but whilst theorizing the development of delusions and hallucinations, they cannot yet formulate the persistence of these symptoms. Lastly, the cognitive behavioural model proposed by Garety et al. (2001) aims to explain maintenance of symptoms, rather than their genesis. The researchers of this model believe that when stressful events trigger an individual with a biopsychosocial predisposition for psychosis, this results in emotional change, cognitive dysfunction and anomalous experiences. These then lead to the appraisal of the experience, which is influenced by dysfunctional schemas of the world and self, isolation and adverse environments, and reasoning and attributional biases. These lead to the emergence of positive symptoms, and are maintained by their reasoning and attributions, dysfunctional schemas, emotional processes, and the appraisal of psychosis. This cognitive model uses cognitive behavioural therapy to treat psychosis. The target is positive symptoms, similarly to other cognitive and neurocognitive models, and the aim is to improve cognitive processes and perception in the brain. Positive symptoms are the symptoms most likely to be interfered with, due to the intrinsic nature of negative symptoms.

Psychosis is a condition with a wide spectrum of symptoms and disorders that do not have to concur. They have many different causal pathways and outcomes. Cognitive models emphasize and focus on different aspects of the condition, but most of which are relative to positive symptoms. However, positive symptoms, especially delusions, are the most common and distinguishable symptoms to diagnose, as well as in many cases the symptoms that have the most adverse impact on people’s lives. Cognitive models are therefore generally efficient at accounting for the diversity of psychotic symptoms, because they encompass the majority of prominent symptoms.

References:

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