Individual Differences 2: Cognitive

These are the most common symptom of schizophrenia and one of its defining characteristics although not all schizophrenics experience them. They can be represented in any modality e.g. sight, sound and touch. The most common type of hallucinations is hearing voices. However, it is not just schizophrenics that experience hallucinations as they can occur in other mental illnesses such as Parkinson’s and Alzheimer's. Mentally healthy people can experience them from time to time. The most common triggers are stress, lack of sleep and certain drugs prescribed and recreational. Less common triggers include migraines and vision problems and these people do not receive a diagnosis.

• Claiborn (2009) estimated around 2.5-4% of the general population experience at least one hallucination in their life.

• Morrison (1998) Proposed that triggers such as sleep deprivation, can cause some individuals to ‘hear’ voices in maladaptive ways. They then praise these voices inappropriately as belonging to the devil for example. This encourages behaviours such as social withdrawal and self-harm.    

• Frith (1992) Thought we all have a “voice” in our head, which he called our inner voice and think with. He argued schizophrenics fail to monitor this voice, and when hallucinations occur their own inner speech is being misinterpreted.

• Claiborn (2009) estimated around 2.5-4% of the general population experience at least one hallucination in their life.

• Morrison (1998) Proposed that triggers such as sleep deprivation, can cause some individuals to ‘hear’ voices in maladaptive ways. They then praise these voices inappropriately as belonging to the devil for example. This encourages behaviours such as social withdrawal and self-harm.    

• Frith (1992) Thought we all have a “voice” in our head, which he called our inner voice and think with. He argued schizophrenics fail to monitor this voice, and when hallucinations occur their own inner speech is being misinterpreted.

• Cognitive research into schizophrenia has tended to focus on the positive symptoms of the illness such as delusions and hallucinations. Less research has been conducted into the negative symptoms. However, Beck (2008) applied his cognitive triad to schizophrenia.

Beck (2008) Proposed that the individual endorses dysfunctional beliefs about their performance and their ability to experience pleasure, they also hold a cynical and gloomy view of the future. Which can lead to evolution and flatness of affect.     

• This theory was developed by Frith (1979) of schizophrenia. In this theory, schizophrenia is seen as a result of the breakdown of this thought filtering process. Schizophrenics have issues with attention, and are not able to effectively filter non-pertinent information out of the conscious.

• This inability to properly focus cases schizophrenics to give the impression of disordered thought, and can possibly account for hallucinations, delusions and disordered speech.

• In this theory, things in the environment that would usually be filtered out as irrelevant or unimportant are now interpreted in conscious awareness are more significant than they really are.

• Supporting evidence comes from Bentall (1994) as he argued that schizophrenics have attentional bias towards stimuli of threatening and emotional behaviour, particularly stimuli associated with violence, pain etc. They are more likely to perceive a stimuli as threatening when it isn’t. This could explain paranoid delusions. A schizophrenic may misrepresent an event as threatening due to an attentional bias on stimuli perceived as threatening.

• The inability of schizophrenics to effectively focus their attention on the appropriate elements of the environment may also account for why many schizophrenics have problems with memory recall of events. They are not attending to the world in a logical way, and so the memories that they form are incomplete or incomprehensible.

• All of us have what is called a Theory of Mind (ToM). ToM refers to our ability to understand that we have our own minds, and that our minds are different and distinct. ToM helps us to understand that other people have their own minds, and that our minds are different and distinct. ToM helps us understand that our desires and points of view are not necessarily the same as others. Also, we understand that others may not have access to the information we have.

• We are not born with a ToM. It starts to develop in children around the age of 2-3 years old, but does not become fully formed until much later in childhood. Very young children do not have a ToM, and are unable to understand that their minds are separate from the minds of others. Young children may believe that if they know something, others will also know it.

Supporting evidence of this is Frith (1992) he argues that some of the cognitive impairments shown by schizophrenics are due to a faulty ToM. Frith argues that schizophrenics do not have a clear grasp of their own minds, and that they misunderstand their own thought processes. The result is that they are unable to distinguish between actions that are brought about through external forces, and those that are generated internally.

• This theory cannot explain the development of schizophrenia in people who do not experience hallucinations or hear voices.

• Morrison’s theory may explain how schizophrenia may result from hearing voices, but has a number of weaknesses. For example, it does not explain where the voices and hallucinations initially come from.

• If this theory was true, then presumably by highlighting to the schizophrenic the chain of events that started with them hearing a voice and led to the development of schizophrenia this should get rid of the symptoms. However, even when a patient knows that they are schizophrenic, and that the voices are not real, it does not eradicate the symptoms.

• Beck’s cognitive triad was developed to explain depression. It is unclear how well this theory can be applied to schizophrenia.

• Does not explain where the initial negative thoughts come from that began the cognitive triad.

• Cannot explain the positive symptoms of schizophrenia.

• An impaired ToM has been heavily implicated in people who are diagnosed with autism. It doesn’t explain what causes this impairment to manifest as autism in one person, and schizophrenia in someone else.

• It also doesn’t explain where this impairment comes from.

• Cognitive theories do seem to provide a good explanation for the positive symptoms of schizophrenia. However, they are limited in their ability to explain the negative symptoms.

• Pure cognitive theories of schizophrenia are limited in usefulness as they ignore the biological components of the disorder, which as we have seen have a big influence. However, modern cognitive neuroscience bridges the gap between cognitive and biological explanations, and may provide a more thorough explanation than either approach can alone.

One issue with cognitive explanations is that they can be reductionist. They ignore the social and cultural factors involved in the development and maintenance of the illness. However, cognitive neuroscience does take into account both biological and cognitive explanations, so maybe it’s a little more holistic than any single explanation.