With advances in screening and early detection, coupled with improved treatment and care, the number of cancer survivors has risen exponentially over the past several decades. Moreover, because age is the most significant risk factor for cancer, the majority of cancer survivors are over 65 years of age. Finally, cancer survivors often experience significant health issues for many years after the treatment has subsided. In the current article, we describe select research that has focused on changes to cognitive performance associated with cancer and its treatment, i.e., alterations that have been colloquially referred to as chemobrain. Although understanding changes in cognitive performance following cancer treatment is an active area of inquiry, the experience of older adult cancer survivors has been somewhat neglected. For example, evidence is mixed as to whether changes in cognitive performance associated with normal aging are exacerbated by cancer survivorship status. It is also unclear whether a history of cancer makes it more or less likely that a person will be diagnosed with dementia or Alzheimer's disease in the future. Finally, we identify a number of areas where existing cognitive aging research can inform studies on cognitive performance following cancer treatment. Future efforts should be directed towards designing studies that focus on the experience of older adult cancer survivors and are informed by the clinical oncology and cognitive aging literature.

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