What are we changing with neurocognitive rehabilitation? Illustrations from two single cases of changes in neuropsychological performance and brain systems as measured by SPECT.

If cognitive remediation is to be developed further, there have to be not only large-scale randomized trials but also detailed analysis of the strategies used to produce improved performance. In this study the strategies adopted by two people who took part in a remediation program are investigated, with their results on neuropsychological tasks and with concomitant brain image data gathered via SPECT while the participant was performing a Verbal Fluency task. After remediation there were improvements in many of the neuropsychological tests, and changes in the scan data. The changes in strategies and brain activation were different for both individuals. One person increased his verbal output but without close monitoring, so also increased his errors. The other participant decreased his output but monitored it more closely, and so decreased the errors. These strategies were reflected in the changes in activation between scans, i.e. increases in temporal areas for the increased output and bilateral decreases in the anterior cingulate and left pre-motor areas for the decreased output case. Together these results imply that the participants continue to use individual strategies which for many of the neuropsychological tasks produced gains. Further investigation of whether it is possible to change idiosyncratic strategy use is needed if we are to develop the efficacy of this remediation technique.