Performance monitoring in lung cancer patients pre- and post-chemotherapy using fine-grained electrophysiological measures

Abstract

No previous event-related potentials (ERPs) study has explored the error-related negativity (ERN) - an ERP component indexing performance monitoring - associated to cancer and chemotherapy-induced cognitive impairment in a lung cancer population. The aim of this study was to examine differences in performance monitoring in a small-cell lung cancer group (SCLC, C +) 1-month following chemotherapy and two control groups: a non-small cell lung cancer patient group (NSCLC, C -) prior to chemotherapy and a healthy control group (HC). Seventeen SCLC (C +) underwent a neuropsychological assessment and an ERP study using a flanker and a stop-signal paradigm. This group was compared to fifteen age-, gender- and education-matched NSCLC (C -) and eighteen HC. Between 20 and 30% of patients in both lung cancer groups (C + and C -) met criteria for cognitive impairment. Concerning ERPs, lung cancer patients showed lower overall hit rate and a severe ERN amplitude reduction compared to HC. Lung cancer patients exhibited an abnormal pattern of performance monitoring thus suggesting that chemotherapy and especially cancer itself, may contribute to cognitive deterioration. ERN appeared as an objective laboratory tool sensitive to cognitive dysfunction in cancer population.

Keywords: Chemobrain; Cognitive impairment; Error-related negativity (ERN); Event-related potentials-ERP; Lung cancer; Performance monitoring.

Fig. 1

A. Grand averages of response-locked event-related potentials in ‘go’ trials at midline electrodes (Fz, Cz, Pz) for the three groups (controls, C + group and C– group). Depicted are ERPs for correct trials (dashed lines) and choice errors (thick solid lines). Data were bandpass filtered (bandpass 2–8 Hz) (U.M. Kramer et al., 2007). The grey shadows indicate the interval where the difference between conditions is statistically significant. B. Three-dimensional isovoltage topographical maps for correct responses (left column) and choice errors (right column) in the 50–150 ms interval for each group. Numbers below each map indicate the scale used.

Fig. 2

A. Grand averages of response-locked event-related potentials in ‘no-go’ trials at midline electrodes (Fz, Cz, Pz) for the three groups (controls, C + group and C– group). Depicted are ERPs for correct trials (dashed lines) and stop errors (thick solid lines). Data were bandpass filtered (bandpass 2–8 Hz). The grey shadows indicate the interval where the difference between conditions is statistically significant. B. Three-dimensional isovoltage topographical maps for correct responses (left column) and stop errors (right column) in the 100–200 ms interval for each group. Numbers below each map indicate the scale used.

Fig. 3

A. Grand averages of response-locked difference waveforms in ‘go’ trials (choice errors – correct trials) at midline electrodes (Fz, Cz, Pz) for each group (Controls: solid line, C + group: dashed line, and C– group: dotted line). The grey shadows indicate the time interval used to define the ERN and CRN amplitudes (50–150 ms). B. Box plot illustrating the amplitude in correct trials and choice errors in the 50–150 ms interval for each group.

Fig. 4

A. Grand averages of response-locked difference waveforms in ‘go’ trials (stop errors – correct trials) at midline electrodes (Fz, Cz, Pz) for each group (controls: solid line, C + group: dashed line, and C– group: dotted line). The grey shadows indicate the time interval used to define the ERN and CRN amplitudes (100–200 ms). B. Box plot illustrating the amplitude in correct trials and stop errors in the 100–200 ms interval for each group.

Fig. 5

A. Grand averages of stimulus-locked event-related potentials at midline electrodes (Fz, Cz, Pz) for the three groups (controls, C + group and C– group). Depicted are ERPs for compatible trials (thick solid lines), incompatible trials (dashed lines) and the difference waveforms (thin solid lines). Data were lowpass filtered (30 Hz). The grey shadows indicate the interval where the difference between conditions is statistically significant. B. Grand averages of stimulus-locked event-related potentials in incompatible trials at midline electrodes (Fz, Cz, Pz) for each group (controls: solid line, C + group: dashed line, and C– group: dotted line). C. Grand averages of stimulus-locked event-related potentials at midline electrodes (Fz, Cz, Pz) pooling together the three groups. Depicted are ERPs for compatible trials (thick solid lines), incompatible trials (dashed lines) and the difference waveforms (thin solid lines). The grey shadows indicate the interval where the difference between conditions is statistically significant.