The contribution of stimulus frequency and spatial attention to the N2 and P3 in Go/Nogo: A multilab replication and new analyses

EEG studies show that stimuli requiring withholding a response (Nogo) elicit larger frontal N2 and frontocentral P3 event-related potentials (ERPs) than stimuli requiring a response (Go). However, the functional significance of these components remains debated due to overlapping neural processes and potential confounds in Go/Nogo tasks. One concern is that Nogo trials are typically less frequent than Go trials to induce a stronger response tendency. Since N2 and P3 are modulated by stimulus frequency, some argue that Nogo effects may reflect a response mismatch signal from infrequent Nogo trials. To test this, Eimer (1993) manipulated Go/Nogo trial frequency, using a 75/25 ratio in Experiment 1 and a 50/50 ratio in Experiment 2. While the N2 and P3 effects were numerically larger in Experiment 1, they remained robust in Experiment 2, with both components showing greater amplitudes for Nogo trials. These findings contradict the response mismatch hypothesis and emphasize the importance of equating trial frequency in Go/Nogo studies. Eimer (1993) also manipulated spatial attention to determine whether the N2 effect reflects an automatic (i.e., attention-independent) process. Results showed that N2 effects were modulated by attentional cues, ruling out a purely automatic process and highlighting the role of processes that affect initial stimulus detection and discrimination in these tasks. The present study replicates Eimer’s Experiment 2 from and assess the robustness of the results across analysis pipelines. Moreover, it will extend the original analyses by determining whether 50/50 Go/Nogo paradigms reliably induce prepotent response tendencies. As part of the #EEGManyLabs project, 5 labs will independently replicate the original study, ensuring high statistical power. Results will be integrated via meta-analysis, offering insights into the replicability of classic EEG findings and N2/P3 sensitivity to stimulus frequency and spatial attention in Go/Nogo tasks. The large dataset will serve as a valuable resource for future meta-analyses.