Insight in schizophrenia: From conceptualization to neuroscience

Abstract

Lack of insight into illness is a prevalent and distinguishing feature of schizophrenia, which has a complex history and has been given a variety of definitions. Currently, insight is measured and treated as a multidimensional phenomenon, because it is believed to result from psychological, neuropsychological and organic factors. Thus, schizophrenia patients may display dramatic disorders including demoralization, depression and a higher risk of suicide, all of which are directly or indirectly related to a lack of insight into their illness, and make the treatment difficult. To improve the treatment of people with schizophrenia, it is thus crucial to advance research on insight into their illness. Insight is studied in a variety of ways. Studies may focus on the relationship between insight and psychopathology, may view behavioral outcomes or look discretely at the cognitive dysfunction versus anatomy level of insight. All have merit but they are dispersed across a wide body of literature and rarely are the findings integrated and synthesized in a meaningful way. The aim of this study was to synthesize findings across the large body of literature dealing with insight, to highlight its multidimensional nature, measurement, neuropsychology and social impact in schizophrenia. The extensive literature on the cognitive consequences of lack of insight and the contribution of neuroimaging techniques to elucidating neurological etiology of insight deficits, is also reviewed.Key words: cognition impairment, conceptualization, insight, neuroanatomy, schizophrenia.A MONG PATIENTS WITH psychiatric disorders, patients with schizophrenia more often exhibit poor insight concerning their mental disorder. 1 The World Health Organization (WHO) International Pilot Study of Schizophrenia in different cultures found that 'lack of insight' was an almost invariable feature of acute and chronic schizophrenia. That study found that 50-80% of patients lack, either partially or totally, insight into their mental disorder.2 A rich literature indicated that unawareness of illness is associated with defects in cognitive functions such as attention, memory, language, executive functioning and social cognition. [3][4][5][6][7][8][9] Furthermore, poor insight in schizophrenia has been proposed to result in poor treatment compliance, 10,11 poor social and interpersonal functioning, 12,13 poor prognosis, and higher risk of relapse.14 Other studies reported that poor insight may increase the incidence of depression, hopelessness, low self-esteem [15][16][17][18][19] and more generally poor quality of life (QOL). 13,[20][21][22] Over the past decade there has been an increase in research on the conceptualization and assessment of insight, but the relationship between insight and neurocognitive impairment, severity of psychopathology or *Correspondence: Mounir Ouzir, PhD, Laboratory of Clinical Neuroscience and Mental Health, University Hassan II, Faculty of Medicine and Pharmacy, 19 Rue Tarik Ibnou Ziad, BP: 9154 Mers Sultan, 20000 Casablanca, M...

The relationship between cognitive insight and depression in psychosis and schizophrenia: A review and meta-analysis

“…More specifically, increased self-reflection is positively correlated with awareness of delusions and negatively with delusion severity (Engh et al, 2010). Additionally, a positive relationship between delusion severity and self-certainty has been consistently reported (Warman et al, 2007;Engh et al, 2010;Ouzir et al, 2012). These studies demonstrate evidence of both overlap and distinctiveness between clinical and cognitive insight and this might have clinical implications (Beck et al, 2011;Pijnenborg et al, 2011;Pijnenborg et al, 2014).…”

An integrative model of the impairments in insight in schizophrenia: emerging research on causal factors and treatments

“…A fourth area of potential research includes future investigations that serve to elucidate how brain structure and function impact insight, as investigations into this could be informative for developing both advances into etiological theory and novel therapeutic approaches. To date, imaging studies suggest that a number of areas and anomalies may subserve impaired insight, including reduced total brain volume, ventricular enlargement, frontal lobe atrophy, reduced frontal volume, gray matter deficits in the cingulate, precuneus, temporal and parietal lobes [68]. However, continued research is needed for replication as well as to clarify how these abnormalities fit together and manifest clinically as impaired insight.…”

“…Several studies have indeed suggested that a lack of insight in schizophrenia spectrum disorders is related to aberrant structure and function of the frontocortical systems (see [68] for detailed review). Abnormalities related to insight in schizophrenia include reduced total brain volume, ventricular enlargement, frontal lobe atrophy, reduced frontal volume, and gray matter deficits in the cingulate, precuneus, temporal, and parietal lobes [68].…”

“…Abnormalities related to insight in schizophrenia include reduced total brain volume, ventricular enlargement, frontal lobe atrophy, reduced frontal volume, and gray matter deficits in the cingulate, precuneus, temporal, and parietal lobes [68]. More recent investigations suggest that the complexity of insight as a construct may be reflected in neurobiology, as studies suggest that unawareness of illness and misattribution of symptoms may have independent biological bases in schizophrenia [58], with others reporting alterations in functional connectivity related to self-reflectivity and ultimately insight [69].…”

Awareness of illness and suicidal behavior in delusional disorder patients

“…For many decades, poor insight has been considered a prevalent feature in patients diagnosed with chronic psychotic disorders 1 . The vast majority of scientific literature has defined insight as a multidimensional concept that includes awareness of a mental illness, recognition of the need for medication, awareness of the social consequences, and awareness of the presence of psychotic symptoms and the attribution of symptoms to the illness 2 .…”