Differential effects of paclitaxel treatment on cognitive functioning and mechanical sensitivity.

Treatment for cancer has been indicated to negatively impact the quality of life for patients. Specifically, chemotherapy has been associated with fatigue, nausea, and peripheral neuropathy. More recently, chemotherapy has been found to be related to cognitive impairment in various domains including working memory, information processing speed, and visual attention. At this time, the mechanisms underlying cognitive impairment are not understood, and there is currently no treatment for this condition. The purpose of this study was to examine the development of chemotherapy-induced cognitive impairments and symptoms of peripheral neuropathy. While receiving the chemotherapeutic agent Taxol, animals were tested daily in the Five Choice Serial Reaction Time Task (5CSRTT), a task which requires animals to respond to a visually presented stimulus in order to obtain reinforcement. In addition, animals were tested for the development of peripheral neuropathy, measured by changes in sensitivity to mechanical stimulation. The results indicate Taxol treated animals developed mechanical sensitivity within 24h after the first injection of chemotherapy. However, relative to control animals, Taxol treated animals did not exhibit alterations in cognitive function in the 5CSRTT. These differential findings may provide interesting insight into the mechanisms underlying chemotherapy-related cognitive impairment.