Neural correlates of chemotherapy-induced emotion regulation impairment in breast cancer patients.

To investigate the chemotherapy-induced emotion regulation impairment and its neural correlates in breast cancer (BC) patients by event-related potentials (ERP), seventeen BC patients were investigated on emotion regulation paradigms while undergoing the recording of an event-related potential (ERP) both before and after chemotherapy. The performance of behavioral and ERP was compared for the data collected before and after chemotherapy (BCB and BCA, respectively). The correlation of the difference between the peak and the latency of each component before and after chemotherapy were compared with the difference in behavior (RT and AR). BC patients showed a lower accuracy rate in both explicit and implicit emotion identification in BCA compared to that in BCB. Further, both the N1 and P2 components were significantly delayed. The peak values of the N1 and P2 in BCA were significantly higher than those in BCB, whereas the peak value of the N2 in BCA was significantly lower than that in BCB. There was a positive correlation between the difference in latency at the CZ (r=0.88), F3 (r=0.97) and FZ (r=0.85) points in the N1 component and the RT. The difference in latency at the FCZ point in the N2 (r=0.88) component is positively correlated with the AR. The difference in peak value at the CPZ (r=0.89) point in the N1 component is positively correlated with the RT. Both the implicit and explicit emotional processing was compromised in BC patients following chemotherapy. These emotional processing deficits may be related to the changes of the N1, N2 and P2 of the ERP.