Long-term reliability of electrophysiologic response control parameters

The execution (Go) and the inhibition (NoGo) of a motor response are basic cognitive processes that can be assessed by means of a simple neuropsychological Go-NoGo task: the Continuous Performance Test (CPT), Simultaneous electro-physiologic investigations revealed that the NoGo condition of the CPT is associated with a clearly more anterior brain electrical activity compared with the Go condition. Recently, it has been shown that this NoGo anteriorization effect during a response control paradigm can be measured quantitatively with the electrophysiologic centroid method. The objective of the current study, therefore, was to determine the long-term reliability of the topographic measures of cognitive response control (i.e., location of the Go and the NoGo centroid and the NoGo anteriorization). For this purpose, a 21-channel EEG was recorded twice from 13 healthy volunteers during their execution of a cued CPT (O-X version). The time interval between test and retest was 2.74 years (range, 2.41 to 2.97 years). Statistical analysis of the event-related Go and NoGo potentials revealed an excellent test-retest reliability, as expressed by Pearson's product moment correlation coefficients of more than 0.85 (P less than or equal to 0.0005) and intraclass correlation coefficients of more than 0.90 (P less than or equal to 0.0005) for all three topographic measures. These results indicate that these electrophysiologic parameters present with superior long-term reliability and that they may be applied as electrophysiologic trait markers of response control mechanisms in the human brain.