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C3 Implications in the real world-Applications. Schizophrenia: Individual Differences 2- Cognitive

Schizophrenia – Individual differences 2: Cognitive Approach

The Cognitive ApproachBefore we go into details about cognitive explanations of schizophrenia, we shall review what we learned about this approach in Year 12.

From memory, what can you remember about the following cognitive ideas?

Using the principles above, develop a possible cognitive theory of schizophrenia

The cognitive approachThe cognitive approach views behaviour and thoughts as being a product of internal mental processes. In this approach, the brain can be seen as a computer, with these internal mental processes acting as “software”. These internal mental processes help us

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The computer analogy

Internal mental processes

Schemas

The cognitive triad

Automatic negative thoughts


make sense of the world and control our behaviour. Mental illness is therefore explained by problems with these internal mental processes. Schizophrenia could be explained by using cognitive ideas and can be associated with problems at all stages of cognition. The symptoms of the disorder could be explained through problems with the processes that govern perception, language or attention for example. One key area that schizophrenics have impairments in is social cognition, that is making sense of and being able to interact in the social world. In particular, schizophrenics have problems in the processing of emotion, social cues, and the Theory of Mind (ToM).

A pure cognitive approach would only use cognitive ideas, and make no reference to biological factors. However, modern cognitive psychologists seek to connect the cognitive deficits of schizophrenics with biological changes in the brain (cognitive neuroscience). We already saw some of this when we looked at the structural abnormalities explanation of schizophrenia, which attempted to link the biological differences in the brains of schizophrenics with the symptoms of the illness. Therefore, most cognitive psychologists would not deny an underlying biological underpinning for the disorder, but rather aim to explain how and why people with schizophrenia display abnormal social and cognitive behaviours.

As stated above, it is likely that schizophrenia affects many different cognitive processes. However, to examine every potential cognitive process would take a long time. What is presented below is just a selection of the key cognitive deficits that have been linked with schizophrenia.

HallucinationsHallucinations are a common symptom of schizophrenia, and one of its defining characteristics (although not all schizophrenics will experience hallucinations, and those who do vary greatly in the severity or regularity of their hallucinations). Hallucinations can be in any modality (e.g. sight, sound, touch etc). One of the most common type of hallucination in schizophrenia is hearing voices.

However, schizophrenics are not the only people who experience hallucinations or hear voices. Hallucinations can occur in other mental illnesses (bipolar disorder, Parkinson’s or Alzheimer’s for example). Also, many otherwise mentally healthy people can experience hallucinations from time to time. Hallucinations can be triggered by a variety of triggers. Stress, lack of sleep and certain drugs (both prescribed and recreational) are common triggers. Migraines and vision problems are less common causes of hallucinations. These people may show no other symptoms of schizophrenia, and so not receive a diagnosis. It is estimated that around 2.5-4% of the general population have experienced hallucinations at least once in their life (Claiborn, 2009).

.An additional theory to explain why schizophrenics hear voices comes from Frith (1992). We all have a “voice” in our head. This is our inner voice. It is this voice that we think with, and for the majority of us, we feel that this inner voice is ours and we are in control of it. Frith however argues that schizophrenics fail to monitor their own thoughts, misattributing them to the outside world. When a person hears voices, it is actually their own inner speech being misinterpreted. Frith speculated that the cognitive deficits were linked to an irregularity in the neuronal pathways running between the septo-hippocampal system and the prefrontal cortex.

This theory is supported by McGuire et al. (1996) who found that schizophrenics to have reduced activity in those parts of the brain involved in monitoring inner speech. Also, other research has using PET scans has shown there is under-activity in the frontal lobe of the brain of schizophrenics which is linked to self-monitoring and so provides biological support for this explanation.

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Negative symptomsCognitive 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.

Summarise how Beck (2008) explains how the cognitive triad can explain some

symptoms of schizophrenia

Lack of preconscious filtersTake a moment to pay attention to your surroundings. What information are you receiving from your environment that you are consciously aware of (e.g. the writing on this handout, the teacher’s voice). What other information is in the environment that you

are not aware of until to make a conscious effort (e.g. the ticking of a clock, the feel of your socks on your ankles)Our brains are constantly receiving information vast amounts of information from the world around us. If we tried to attend to all of the possible information in our environment, we would soon become overwhelmed and unable to function. All of the information from our environment enters our preconscious (this is a different meaning of the word than how Freud uses it). Preconscious thought occurs without awareness. The information that

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Consciously aware of:

Not consciously aware of without effort:


the brain interprets as the most pertinent enters the conscious mind. The rest is filtered out.

Look at the picture above. Identify what information the driver is attending to, and what

they are filtering out

Frith (1979) developed the “Attention Deficit Theory” 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 consciousness. This inability to properly focus causes schizophrenics to give the impression of disordered thought, and can possibly account for hallucinations, delusions and disorganised speech.

In this theory, things in the environment that would usually be filtered out as irrelevant or unimportant are now interpreted in conscious awareness as more significant than they really are. According to Frith, these cognitive deficits are caused by abnormalities in those areas of the brain that uses use dopamine, especially the prefrontal cortex. His research has shown that schizophrenics have reduced blood flow to these areas (indicating reduced brain activity) during certain cognitive tasks.

Further arguments for the theory that schizophrenics have deficiencies in their ability to filter irrelevant information comes from Bentall (1994). He argued that schizophrenics have attentional bias towards stimuli of a threatening and emotional nature, particularly stimuli associated with violence, pain etc. They are also 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.

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Information attended to:

Information filtered out:


Look at the picture above. What might someone with an attentional bias towards

threats focus on?

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.

Compromised theory of mindAll of us have what is called a Theory of Mind (ToM). ToM refers to our ability to understand that we have our own minds, that other people have their own minds, and that our minds are different and distinct. ToM helps us understand that our own desires and points of view are not necessarily the same as others. Also, we understand that other people 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. See the example on the following page.

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C3 Implications in the real world-Applications. Schizophrenia: Individual Differences 2- CognitiveHow will someone who has a fully formed ToM answer the question above? What about someone without a working ToM? Why?

ToM also helps us understand our own minds. We are able to understand that our actions and thoughts are caused by ourselves, and are generated internally rather than by any external force. If you think “I want to eat chips”, your ToM means that you understand that this thought has come from inside your own head. It is your own, self-generated thought.

Frith (1992) 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. For example, a schizophrenic may believe that they are controlling what another person is saying (misattributing an internal force for an external action) or believe that their thoughts have been inserted by aliens (misattributing an external force for an internal action)

Frith believes that most of the symptoms of schizophrenia can be explained in terms of deficits in three cognitive processes:

1. Inability to generate willed action; someone with schizophrenia may be unable to effectively generate action, in other words, not be able to plan and carry out a behaviour. They may not be able to do tasks that they need to do, or may forget which tasks that have done and which ones that haven’t. This could explain the negative symptom of avolition.

2. Inability to monitor willed action; schizophrenics may be unaware of their own intentions and the “sense of effort” that goes into generating behaviour. They are only able to monitor their actions on the basis by observing the consequences of their behaviour once it has already been carried out. In the absence of awareness of their own intentions, schizophrenics may interpret their actions as being caused by an external force. For example, a schizophrenic may drink a glass of water because they are thirsty. However, the motivation and the intention behind the action is inaccessible to the patient, so they interpret the behaviour as mind control messages from their TV screen.

3. Inability to monitor the beliefs and intentions of others.: due to problems with their ToM, schizophrenics may struggle to monitor and interpret the behaviour of others. This can lead to misunderstandings that could result in some of the delusions of

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persecution experienced by many schizophrenics. For example, a schizophrenic may believe that others can hear their thoughts, or that a stranger who seems angry is angry because of them and intends to do them harm.

According to Frith, problems with the ToM of schizophrenics is due to a disconnection between frontal areas of the brain concerned with action and more posterior areas of the brain that control perception. He has found some evidence for this explanation by using brain scans.

EvaluationAs you can see, there are many branches to the cognitive explanation of schizophrenia. We will first evaluate each component we have looked at above, and then give an overall evaluation of cognitive explanations.

Explaining hallucinations 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.

It does not explain what is different about schizophrenics that causes them to misappraise these voices. If 2.5-4% of people experience hearing voices at least once in their life, then why aren’t there the same proportion of schizophrenics? What causes some people who hear voices to develop schizophrenia, and others not to?

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

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 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.

Negative 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.

Lack of preconscious filters States that symptoms of schizophrenia are caused by an

ability to filter out irrelevant stimuli. But what causes this inability in the first place?

Compromised ToM An impaired ToM has been heavily implicated in people who

are diagnosed with autism. What causes this impairment to manifest as autism in one person, and schizophrenia in someone else?

Where did this impairment come from?

Overall evaluation Cognitive theories do seem to provide a good explanation of 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 alone can.

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o For example, many studies in the cognitive approach not only examine cognitive deficits in schizophrenics, but also in close members of their family. It has been found that quite often, the families of schizophrenics share these cognitive deficits, even if they have not been diagnosed as schizophrenic themselves. This points towards a genetic component of the disorder.

One methodological issue is that many of these studies are lab experiments. The participants are typically brought to a lab and asked to do some sort of cognitive test, usually on a computer.

What are the strengths of this?

What are the weaknesses of this?

Another methodological issue with many of the studies is that the majority of schizophrenics are prescribed antipsychotic medication. As we will find out in a later lesson, this type of medication can have a big effect on the brain. Therefore, any study that uses medicated schizophrenics may have issues with generalisability to schizophrenics who are not medicated. Also, the cognitive deficits identified in research may be the result of the medication, not of the illness. There may also be deficits that are hidden by the effect of medication. However, for obvious reasons, conducting research on non-medicated schizophrenics may be impractical and unethical.

Linked in with this issue is that Cognitive Behavioural Therapy (looked at in a later lesson) has limited effectiveness for treating schizophrenia when not combined with antipsychotic medication. This suggests that cognitive explanations cannot be the only explanation of schizophrenia.

o That said however, cognitive explanations can be useful in developing methods that can help schizophrenics cope with the symptoms of the illness, even if it cannot provide a cure.

One of the biggest issues with that of cause and effect.Apply the issue of cause and effect to the cognitive explanation of schizophrenia.

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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 it’s a little more holistic than any single explanation.

Cognitive theories leave a little more room for free will than purely biological explanations. If schizophrenia is caused by errors in thinking, then there is the opportunity to a schizophrenic to alter their thinking, possibly with CBT.

o However, this could cause an ethical issue. Cognitive explanations may be putting the blame for the illness within the schizophrenic. All they need to do is change their thinking! Due to the lack of control schizophrenics experience over their illness, perhaps deterministic explanations may be more valid.

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