The P300 as marker of inhibitory control – Fact or fiction?

Latency and amplitude of the stop-signal P3 event-related potential are related to inhibitory GABAaactivity in primary motor cortex

“…Indeed, EMG and MEP recordings show that the first signs of motor-system inhibition in these measures emerge as early as ∼150ms after the onset of a stop-signal (Jana, Hannah, Muralidharan, & Aron, 2020; Raud & Huster, 2017). In line with this, recent studies have shown that cortical signals that are related to stopping success can also be found in similar time ranges (Huster et al, 2020; Jana et al, 2020; Skippen et al, 2020; Wessel, 2019). Just like the beforementioned EMG and MEP measurements of functional motor inhibition, these cortical signatures often precede both SSRT, as well as the typical onset latency of the fronto-central P3, by several dozens of milliseconds.…”

“…While we did find a positive correlation between SSRT and P3 onset (replicating previous work on the EEG-behavior relationship; cf. Huster et al, 2020; Wessel & Aron, 2015), and while P3 onset was in turn correlated with SSRT as well (the main result of the current study), SICI and SSRT themselves were not correlated in our dataset. There are several potential reasons for this.…”

“…A later study, however, used single-trial analyses to show that the onset of the fronto-central stop-signal P3 (instead of its peak) not only occurs early enough to fall within the pre-SSRT time period, but is also highly positively correlated with SSRT– i.e., subjects with a a faster onset of the stop-signal P3 also showed faster SSRT (Wessel & Aron, 2015). While this latter association has since been independently replicated (Huster, Messel, Thunberg, & Raud, 2020) the association between the stop-signal P3 and inhibitory processing still remains controversial. One argument is that additional ERPs, including ERPs that predate the P3 and likely reflect attentional processes, also correlate with SSRT (Huster et al, 2020; Skippen et al, 2020).…”

“…While this latter association has since been independently replicated (Huster, Messel, Thunberg, & Raud, 2020) the association between the stop-signal P3 and inhibitory processing still remains controversial. One argument is that additional ERPs, including ERPs that predate the P3 and likely reflect attentional processes, also correlate with SSRT (Huster et al, 2020; Skippen et al, 2020). In addition to this debate focusing on the electrophysiology of stopping, the fundamental assumptions underlying the SSRT computation have also recently been called into question themselves, with some authors arguing that SSRT systematically overestimates the latency of the stopping process – specifically because the classic SSRT computation does not take into account trials in which the inhibitory control process is not triggered at all (Matzke, Curley, Gong, & Heathcote, 2019; Patrick Skippen et al, 2019).…”

Partial response electromyography as a marker of action stopping

“…The earlier timing of the prEMG peak latency compared to the SSRT has been replicated in a number of independent studies (Hannah et al, 2020;Jana et al, 2020;Raud et al, 2020aRaud et al, , 2020bTatz et al, 2021;Thunberg et al, 2020). However, while the existence of the prEMG is relatively well-established, its characteristics and utility has not been explored sufficiently to declare it an unambiguous biomarker of the stopping latency.…”