The neurocognitive literature on test performance in schizophrenia is reviewed quantitatively. The authors report 22 mean effect sizes from 204 studies to index schizophrenia versus control differences in global and selective verbal memory, nonverbal memory, bilateral and unilateral motor performance, visual and auditory attention, general intelligence, spatial ability, executive function, language, and interhemispheric tactile-transfer test performance. Moderate to large raw effect sizes (d > .60) were obtained for all 22 neurocognitive test variables, and none of the associated confidence intervals included zero. The results indicate that schizophrenia is characterized by a broadly based cognitive impairment, with varying degrees of deficit in all ability domains measured by standard clinical tests.

Neurocognitive Deficit in Schizophrenia: A Quantitative Review of the Evidence

The ability to "mentalize," that is to understand and manipulate other people's behavior in terms of their mental states, is a major ingredient in successful social interactions. A rudimentary form of this ability may be seen in great apes, but in humans it is developed to a high level. Specific impairments of mentalizing in both developmental and acquired disorders suggest that this ability depends on a dedicated and circumscribed brain system. Functional imaging studies implicate medial prefrontal cortex and posterior superior temporal sulcus (STS) as components of this system. Clues to the specific function of these components in mentalizing come from single cell recording studies: STS is concerned with representing the actions of others through the detection of biological motion; medial prefrontal regions are concerned with explicit representation of states of the self. These observations suggest that the ability to mentalize has evolved from a system for representing actions.

https://science.sciencemag.org/content/sci/286/5445/1692.full.pdf

Interacting Minds--A Biological Basis

https://cris.maastrichtuniversity.nl/ws/files/64205713/viechtbauer_2011_the_relationship_between_neurocognition_and.pdf

The relationship between neurocognition and social cognition with functional outcomes in schizophrenia: a meta-analysis.

Background We examined relapse after response to a first episode of schizophrenia or schizoaffective disorder. Methods Patients with first-episode schizophrenia were assessed on measures of psychopathologic variables, cognition, social functioning, and biological variables and treated according to a standardized algorithm. The sample for the relapse analyses consisted of 104 patients who responded to treatment of their index episode and were at risk for relapse. Results Five years after initial recovery, the cumulative first relapse rate was 81.9% (95% confidence interval [CI], 70.6%-93.2%); the second relapse rate was 78.0% (95% CI, 46.5%-100.0%). By 4 years after recovery from a second relapse, the cumulative third relapse rate was 86.2% (95% CI, 61.5%-100.0%). Discontinuing antipsychotic drug therapy increased the risk of relapse by almost 5 times (hazard ratio for an initial relapse, 4.89 [99% CI, 2.49-9.60]; hazard ratio for a second relapse, 4.57 [99% CI, 1.49-14.02]). Subsequent analyses controlling for antipsychotic drug use showed that patients with poor premorbid adaptation to school and premorbid social withdrawal relapsed earlier. Sex, diagnosis, obstetric complications, duration of psychotic illness before treatment, baseline symptoms, neuroendocrine measures, methylphenidate hydrochloride challenge response, neuropsychologic and magnetic resonance imaging measures, time to response of the initial episode, adverse effects during treatment, and presence of residual symptoms after the initial episode were not significantly related to time to relapse. Conclusions There is a high rate of relapse within 5 years of recovery from a first episode of schizophrenia and schizoaffective disorder. This risk is diminished by maintenance antipsychotic drug treatment.

https://jamanetwork.com/journals/jamapsychiatry/articlepdf/204795/yoa8094.pdf

Predictors of relapse following response from a first episode of schizophrenia or schizoaffective disorder.

The term theory of mind (ToM) refers to the capacity to inferone’sownandother persons’mentalstates. Asubstantial body of research has highlighted the evolution of ToM in nonhuman primates, its emergence during human ontogeny,and impaired ToMin avarietyof neuropsychiatric disorders, including schizophrenia. There is good empirical evidence that ToM is specifically impaired in schizophrenia andthatmanypsychoticsymptoms—forinstance,delusions ofaliencontrolandpersecution,thepresenceofthoughtand language disorganization, and other behavioral symptoms—maybestbeunderstoodinlightofadisturbedcapacity in patients to relate their own intentions to executing behavior, and to monitor others’ intentions. However, it is still under debate how an impaired ToM in schizophrenia isassociatedwithotheraspectsofcognition,howtheimpairmentfluctuateswithacuityorchronicityoftheschizophrenic disorder, and how this affects the patients’ use of language and social behavior. In addition to these potential research areas,futurestudiesmayalsoaddresswhetherpatientscould benefit from cognitive training in this domain.

/pdf/theory-of-mind-in-schizophrenia-a-review-of-the-literature-24htih6esf.pdf

“Theory of Mind” in Schizophrenia: A Review of the Literature

Schizophrenia, symptomatology and social inference: Investigating “theory of mind” in people with schizophrenia

BACKGROUND Although previous studies have attempted to identify predictors of outcome in schizophrenia, few have prospectively studied first episode patients for an adequate follow-up period.

METHOD The psychopathological predictors of outcome were investigated in a subgroup of 51 subjects, originally included in the Northwick Park study of first episode schizophrenia who were followed up 7.3 years (s.d. 1.1, range 5.3-10.3) after first admission in the Harrow study. Forty-four subjects (24 men, 20 women) were traced. Outcome measures were time to first readmission, occupational level and total duration of hospital admission at five years after first admission.

RESULTS A survival analysis of time to first relapse revealed that the presence of subjective feelings of depression (CATEGO syndrome SD) during the first admission was associated with early relapse while the presence of depressive delusions (CATEGO syndrome DD) and higher educational attainment protected against early relapse. Total duration of hospitalisation at five years after first onset was positively associated with the presence of CATEGO syndromes SD and OD (biological features of depression) and negatively associated with female sex. Poor occupational outcome was not significantly associated with any psychopathological predictors.

CONCLUSIONS Our findings challenge the conventional view that symptoms of depression are associated with better outcome in schizophrenia.

Prediction of outcome following a first episode of schizophrenia. A follow-up study of Northwick Park first episode study subjects.

The clinical efficacy of two intensive treatment packages (one including the new antipsychotic risperidone and the other not doing so) was compared with that of standard management in 43 patients with long-standing treatment-resistant schizophrenia. Significant differences between the groups in terms of total positive or total negative symptoms were not demonstrated, but the pattern of change between the treatment groups differed, so that benefit in positive symptomatology was seen in both intensive treatment groups and in negative symptomatology in the intensive treatment/risperidone group and the standard group. Changes in general psychopathology were most marked in the risperidone group and were compatible with a relatively non-sedative profile. Using the Disability Assessment Schedule, substantial significant advantages for the intensive treatment groups were found.

A study of enhanced management in patients with treatment-resistant schizophrenia.

Videotaped assessments of standardized interviews were used to ensure blindness in relation to a clinical trial of multifaceted programmes of management in patients with treatment-resistant schizophrenia. The technique, although laborious, was feasible in all patients studied and offered advantages in relation not only to blindness but also to assessing the nature of psychopathological changes in patients with schizophrenic deficit syndrome of severe degree. The method is likely to be useful in further studies assessing the possible advantages of newer antipsychotic drugs.

Gavin Mercer

Papers

Schizophrenia, symptomatology and social inference: Investigating “theory of mind” in people with schizophrenia

Prediction of outcome following a first episode of schizophrenia. A follow-up study of Northwick Park first episode study subjects.

A study of enhanced management in patients with treatment-resistant schizophrenia.

The use of videotaped assessment in relation to a study of enhanced management in treatment-resistant schizophrenia