Brain Correlates of Cognitive Remediation in Schizophrenia: Activation Likelihood Analysis Shows Preliminary Evidence of Neural Target Engagement.

Cognitive remediation training (CRT) for schizophrenia has been found to improve cognitive functioning and influence neural plasticity. However, with various training approaches and mixed findings, the mechanisms driving generalization of cognitive skills from CRT are unclear. In this meta-analysis of extant imaging studies examining CRT's effects, we sought to clarify whether varying approaches to CRT suggest common neural changes and whether such mechanisms are restorative or compensatory. We conducted a literature search to identify studies appropriate for inclusion in an activation likelihood estimation (ALE) meta-analysis. Our criteria required studies to consist of training-based interventions designed to improve patients' cognitive or social functioning, including generalization to untrained circumstances. Studies were also required to examine changes in pre- vs posttraining functional activation using functional magnetic resonance imaging or positron emission tomography. The literature search identified 162 articles, 9 of which were appropriate for inclusion. ALE analyses comparing pre- and posttraining brain activation showed increased activity in the lateral and medial prefrontal cortex (PFC), parietal cortex, insula, and the caudate and thalamus. Notably, activation associated with CRT in the left PFC and thalamus partially overlapped with previous meta-analytically identified areas associated with deficits in working memory, executive control, and facial emotion processing in schizophrenia. We conclude that CRT interventions from varying theoretic modalities elicit plasticity in areas that support cognitive and socioemotional processes in this early set of studies. While preliminary, these changes appear to be both restorative and compensatory, though thalamocortical areas previously associated with dysfunction may be common sources of plasticity for cognitive remediation in schizophrenia.