Cognitive Enhancers in Schizophrenia: non-pharmacological approach

This post is a follow up part to the previous post, which introduced the pharmacological approach to the enhancement of cognition in schizophrenia.

With no major clinical success to date in targeting cognitive deficits in schizophrenia, attention shifted to behavioural, neuro-cognitive interventions. These approaches are based on the assumption that a broad and intensive activation of neural processing systems can stimulate neural resources to improve their functioning. It is believed that intense activation of cognitive (mental) systems damaged in patients with schizophrenia could effectively lead to a general and lasting functional improvement. As a result, several cognitive training strategies have been developed and these can generally be divided into either (1) COGNITION-ENHANCING or (2) COMPENSATORY approaches. The former approaches train patients with laboratory tasks designed to improve specific abilities in various cognitive domains, such as perception, learning, or memory. On the contrary, the latter approaches attempt to bypass cognitive deficits and teach strategies to compensate for them by relying on aids or other processes (Tomás, Roder, & Ruis, 2010).

1) COGNITION-ENHANCING PROGRAMMES

• Cognitive Remediation Therapy (CRT)
• Cognitive Enhancement Therapy (CET)
• Integrated Psychological Therapy for Schizophrenia (IPT) 

CRT aims to improve attention, working memory, cognitive flexibility, planning and executive functioning. CRT is usually administered via use of a computer, with the tasks appearing on the monitor. Research to date demonstrates small to moderate durable effects of CRT and that irrespective of therapy characteristics CRT can provide benefits to patients with cognitive difficulties. Although having more symptoms is associated with smaller effects, all participants were shown to benefit from CRT.

CET is a recovery-phase intervention for symptomatically stable schizophrenic out-patients with reduced relapse risk (Hogarty et al., 2004). This programme tackles areas and disabilities of a wider functional range. For example, specifically designed exercises target analytic logic, decision making, strategic and foresightful planning, as well as the intuitive thinking that supports social cognition (thinking). CET is a small-group approach that combines approximately 75 hours of progressive software training exercises in attention, memory and problem solving with 1.5 hours per week of social cognitive group exercises. Consistent positive results are fund in processing speed and verbal memory. A drawback of this approach is that it is only applicable to patients with a certain intellectual level (with an IQ above 80) who are psychopathologically stable (Tomás et al., 2010).

IPT integrates neuro-cognitive and psychosocial rehabilitation methods.IPT is administered to groups and consists of five, hierarchically organised sub-programs: cognitive differentiation, social perception, verbal communication, social skills and interpersonal problem solving. Studies typically reveal the largest improvements in neuro-cognitive functioning, however, effects on psychosocial functioning tend to be smaller (Roder et al., 2006). More research is currently needed to evaluate the effectiveness of this approach.

2) COMPENSATORY REHABILITATION PROGRAMMES

• Errorless Learning (EL)
• Cognitive Adaptation Training (CAT)

EL involves two main procedures: prevention of errors during the learning phase and automation of perfect task execution (Terrace, 1963). It refers to teaching procedures that are designed in such a way that a learner/patient does not have to - and does not- makes mistakes as she/he learns new information and new procedures.

CAT uses environmental supports and various clues such as signs, check-lists or alarmed drug packaging. It also encourages organisation of belongings and the sequencing of appropriate routines.

In effect, compensatory strategies work to some extent, however, they do not succeed in achieving pre-morbid levels of performance (Tomás et al., 2010). Moreover, they are aimed at people with significant cognitive impairment that is difficult to restore and thus renders them less suitable for people with recent illness who are more intact.

References

Roder, V., Mueller, D. R., Mueser, K. T., & Brenner, H. D. (2006). Integrated psychological therapy for schizophrenia: is it effective? Schizophrenia bulletin, 32 Suppl 1, S81-93. doi:10.1093/schbul/sbl021 

Terrace, H. S. (1963). Discrimination learning with and without errors. Journal of the Experimental analysis of Behaviour, 6, 1-27.

Tomás, P., Roder, I. F. V., & Ruiz, J. C. (2010). cognitive Rehabilitation Programs in Schizophrenia: Current Status and Perspectives. International Journal of Psychology and Psychological Therapy, 10(2), 191-204.