Cancer ‘survivor‐care’: II . Disruption of prefrontal brain activation top‐down control of working memory capacity as possible mechanism for chemo‐fog/brain (chemotherapy‐associated cognitive impairment)

Summary What is known and Objective Cancer chemotherapy‐associated cognitive impairments (termed ‘chemo‐fog’ or ‘chemo‐brain’), particularly in memory, have been self‐reported or identified in cancer survivors previously treated with chemotherapy. Although a variety of deficits have been detected, a consistent theme is a detriment in visuospatial working memory. The parietal cortex, a major site of storage of such memory, is implicated in chemotherapy‐induced damage. However, if the findings of two recent publications are combined, the (pre)frontal cortex might be an equally viable target. Two recent studies, one postulating a mechanism for ‘top‐down control’ of working memory capacity and another visualizing chemotherapy‐induced alterations in brain activation during working memory processing, are reviewed and integrated. Comment A computational model and the proposal that the prefrontal cortex plays a role in working memory via top‐down control of parietal working memory capacity is consistent with a recent demonstration of decreased frontal hyperactivation following chemotherapy. What is new and Conclusion Chemotherapy‐associated impairment of visuospatial working memory might include the (pre)frontal cortex in addition to the parietal cortex. This provides new opportunity for basic science and clinical investigation.