The impairment of basic cognition and social cognition is a well-established feature of schizophrenia. Basic cognition includes cognitive domains such as attention, information processing speed, or memory, whereas social cognition refers to mental operations that underlie social interactions (perception, interpretation, and response to other people’s intentions and behaviors).
Four main social cognitive subdomains have been suggested in recent literature, including emotional processing, the theory of mind, social perception/social knowledge, and attributional bias. The relevance of these deficits is mainly due to the fact that basic cognitive deficits and social cognitive deficits, along with negative symptoms (such as apathy or social withdrawal) are the best predictors of the functional level and quality of life of these patients.
In this context, attempts to remediate those deficits, including cognitive interventions, have recently received increasing attention among researchers. Additionally, several social cognitive treatment programs have been proposed. As expected, the combination of cognitive remediation and social cognitive remediation shows better results than single approaches in functioning, social cognition, and negative symptoms.
Given these promising results, the next step in research should include the identification of the mechanisms through which this kind of intervention improves functioning among patients with schizophrenia. The detection of these mediational factors would bring us more optimized treatment plans by reducing time and cost. Despite the low prevalence of schizophrenia, these objective seems especially relevant given the estimated economic burden of schizophrenia (US$60 billion per year). Part of the reduction of this burden could be attained by selecting the most relevant variables for treatment. A highly significant study carried out by Reeder et al. (2014) demonstrated that change in cognition after cognitive remediation is associated with the cost of care among patients with schizophrenia. These findings strengthen the additional financial gain that could be achieved through this line of research.
In a recent study titled “Mechanisms of functional improvement through cognitive rehabilitation in schizophrenia,” published in the Journal of Psychiatric Research, authors aimed to assess to what extent the improvement on functioning (both performance-based functional capacity and an observer-rated measure of functioning) after cognitive treatment is due to improvement in basic cognition (processing speed, verbal memory, working memory, executive functioning), social cognition (emotion perception, theory of mind, social perception), and negative symptoms. Among all the domains that significantly improved, only verbal memory was found to cause the indirect benefits on functional competence, whereas processing speed emerged as a significant mediator of the observer-rated functioning. Contrary to expectations, neither social cognition nor negative symptoms explained the indirect effect of treatment on functioning.
Overall, these results suggest that more intensive programs addressing verbal memory and processing speed, in particular, may lead therapists to obtain better results regarding functioning in schizophrenia. Nevertheless, the lack of significant mediation throughout social cognitive domains and negative symptoms should not prevent future research from testing these hypotheses.
Since there are still many important intervening factors to uncover, future studies should also search additional outcome measures, such as subjective quality of life, the influence of family dynamics, or work outcome. Additionally, we need to further analyze personal factors (such as age, personality factors, or cognitive & learning styles) that influence the therapeutic process in order to design more customized treatment plans. It would be advisable to also invest time and effort in treatment-resistant patients who need further research.
These findings are described in the article entitled Mechanisms of functional improvement through cognitive rehabilitation in schizophrenia, recently published in the Journal of Psychiatric Research. This work was conducted by Javier Peña, Naroa Ibarretxe-Bilbao and Natalia Ojeda from the University of Deusto and Pedro M. Sánchez, Jose J.Uriarte, Edorta Elizagarate and Miguel Gutierrez from Osakidetza (Public Health System in the Basque Region).