Cognitive insight in schizophrenia encompasses the evaluation and reinterpretation of distorted beliefs and appraisals. We investigated the neuropsychological basis of cognitive insight in psychosis. It was predicted that, like clinical insight, cognitive insight would be associated with a wide range of neuropsychological functions, but would be most strongly associated with measures of executive function. Sixty-five outpatients with schizophrenia or schizoaffective disorder were assessed on tests of intelligence quotient (IQ), executive function, verbal fluency, attention and memory, and completed the Beck Cognitive Insight Scale, which includes two subscales, self-certainty and self-reflection. Higher self-certainty scores reflect greater certainty about being right and more resistant to correction (poor insight), while higher self-reflection scores indicate the expression of introspection and the willingness to acknowledge fallibility (good insight). The self-certainty dimension of poor cognitive insight was significantly associated with lower scores on the Behavioural Assessment of Dysexecutive Syndrome; this relationship was not mediated by IQ. There were no relationships between self-reflection and any neuropsychological measures. We conclude that greater self-certainty (poor cognitive insight) is modestly associated with poorer executive function in psychotic individuals; self-reflection has no association with executive function. The self-certainty and self-reflection dimensions of cognitive insight have differential correlates, and probably different mechanisms, in psychosis.
Traditional ‘insight’ in psychiatry is most commonly viewed as a multi-dimensional construct incorporating awareness of illness, symptoms and the need for treatment (David, 1990 and Amador et al., 1991). Individuals diagnosed with schizophrenia frequently disagree with mental health professionals about the nature of their experiences, and whether they are in need of psychiatric treatment such as medication. Such disagreements are generally viewed as reflecting poor insight on the part of the patient in one or more of these dimensions, which in turn has been linked to poor medication compliance and then to poor outcome (Morgan and David, 2004). There is a more recent suggestion that good insight can have maladaptive consequences for self-esteem and causes distress (Cooke et al., 2007a and Cooke et al., 2007b).
The neuropsychological correlates of traditional insight in schizophrenia have been investigated extensively. While there has been considerable heterogeneity in the results of these studies (Cooke et al., 2005), a recent meta-analysis (Aleman et al., 2006) has shown that poor insight is associated with poor functioning in a range of cognitive domains, including intelligence quotient (IQ), memory and executive function. There is also some evidence to suggest that the associations are particularly strong for the set-shifting and error monitoring aspects of executive function (Aleman et al., 2006).
Recently, Beck and colleagues (Beck and Warman, 2004 and Beck et al., 2004) have distinguished between the traditional approach to insight, which they term ‘clinical insight’, and ‘cognitive insight’, which is a form of cognitive flexibility and encompasses the evaluation and correction of distorted beliefs and misinterpretations. They contend that a crucial cognitive problem in the psychoses (including schizophrenia) is that individuals are unable to distance themselves from their cognitive distortions (e.g., ‘there is a conspiracy against me’), and are also impervious to corrective feedback (Moritz and Woodward, 2006). In contrast, individuals with panic disorder or obsessive–compulsive disorder are more likely to retain the ability to recognise that the conclusions they have made were incorrect, and therefore maintain good cognitive insight.
A lack of cognitive insight in individuals with schizophrenia contributes to both the impairment of clinical insight, and the development of delusions (Beck and Warman, 2004). An impairment in the capacity to evaluate misinterpretations and alter appraisals despite feedback from others, may lead an individual with schizophrenia to disagree with others who call their experiences symptoms of illness; this disagreement is then called an impairment of the ‘awareness of symptoms’ aspect of clinical insight. Poor cognitive insight, it is then argued, may also lead such individuals to conclude that their interpretations (appraisals) of their experiences (e.g., ‘there is a conspiracy against me’) are factually correct (Beck et al., 1994), contributing to the formation and maintenance of delusions. As in other cognitive models, cognitive models of psychosis emphasise the particular role of appraisals in delusional formation and maintenance (Garety et al., 2007). Recent findings have highlighted the potential importance of cognitive insight as a mediator of response to cognitive behavioural therapy for psychosis (Granholm et al., 2005), with increases in cognitive insight associated with reductions in positive, negative and general symptomatology (Granholm et al., 2006).
The Beck Cognitive Insight Scale (BCIS; Beck et al., 1994) has two distinct subscales, self-certainty and self-reflection. Poor insight is characterised by a high degree of certainty in one's (mis)interpretations, and a lack of self-reflectiveness. Beck and his colleagues (Beck and Warman, 2004 and Beck et al., 2008) suggest that the BCIS is an indirect test of a putative impairment of the ‘higher level’ functions in schizophrenia, with the process of distancing oneself from highly salient (delusional) beliefs and having the capacity to view them in perspective requiring intact executive function.
The objective of this study was to examine the neuropsychological correlates of both dimensions of cognitive insight in schizophrenia. We hypothesised that, like clinical insight, cognitive insight will be associated with a wide range of neuropsychological functions, but will be most strongly associated with measures of executive function, particularly measures of set-shifting and error monitoring. These aspects of executive function, as stated earlier, have been found to show most strong associations with clinical insight (Aleman et al., 2006).
