In humans, the ability to withhold manual motor responses seems to rely on a right-lateralized frontal–basal ganglia–thalamic network, including the pre-supplementary motor area and the inferior frontal gyrus. These areas should drive subthalamic nuclei to implement movement inhibition via the hyperdirect pathway. The output of this network is expected to influence those cortical areas underlying limb movement preparation and initiation, i.e. premotor (PMA) and primary motor (M1) cortices. Electroencephalographic (EEG) studies have shown an enhancement of the N200/P300 complex in the event-related potentials (ERPs) when a planned reaching movement is successfully stopped after the presentation of an infrequent stop-signal. PMA and M1 have been suggested as possible neural sources of this ERP complex but, due to the limited spatial resolution of scalp EEG, it is not yet clear which cortical areas contribute to its generation. To elucidate the role of motor cortices, we recorded epicortical ERPs from the lateral surface of the fronto-temporal lobes of five pharmacoresistant epileptic patients performing a reaching version of the countermanding task while undergoing presurgical monitoring. We consistently found a stereotyped ERP complex on a single-trial level when a movement was successfully cancelled. These ERPs were selectively expressed in M1, PMA and Brodmann's area (BA) 9 and their onsets preceded the end of the stop process, suggesting a causal involvement in this executive function. Such ERPs also occurred in unsuccessful-stop trials, that is, when subjects moved despite the occurrence of a stop-signal, mostly when they had long reaction times. These findings support the hypothesis that motor cortices are the final target of the inhibitory command elaborated by the frontal–basal ganglia–thalamic network.

Summary: Objective: To pool observational data on the routine use of perampanel to obtain information on real‐world outcomes and data in populations typically underrepresented in clinical trials.Methods: Individual‐level data of people with epilepsy treated with perampanel at 45 European centers were merged into a single dataset. Prespecified outcomes were: 1‐year retention rate, 1‐year seizure freedom rate (duration ≥6 months), and incidence of treatment‐emergent adverse events (TEAEs). In addition, relationships were explored with logistic regression analyses.Results: The full analysis set comprised 2396 people: 95% had focal seizures; median epilepsy duration was 27 years; median number of concomitant antiepileptic drugs (AEDs) was 2; and median prior AEDs was 6. One‐year retention rate was 48% (1117/2332; 95% confidence interval [CI] 46‐50%), and 1‐year seizure‐free rate (≥6‐month duration) was 9.2% (74/803; 95% CI 7‐11%). Median treatment duration was 11.3 months (1832 patient‐years); median dose was 8 mg. In 388 individuals with available data at 3, 6, and 12 months, responder rates were 42%, 46%, and 39%, respectively. During the first year, TEAEs were reported in 68% of participants (1317/1497; 95% CI 66‐70%). Logistic regression found higher age at perampanel initiation was associated with higher seizure‐free rate, and higher number of prior AEDs with lower seizure‐free rate and lower rates of somatic TEAEs. In 135 individuals aged ≥65 years, 1‐year retention rate was 48% and seizure‐free rate was 28%.Significance: Across a large, treatment‐resistant population, add‐on perampanel was retained for ≥1 year by 48% of individuals, and 9% were seizure‐free for ≥6 months. TEAEs were in line with previous reports in routine clinical use, and less frequent than in the clinical trial setting. No new or unexpected TEAEs were seen. Despite the limitations of observational studies, our data indicate that some individuals may derive a marked benefit from the use of perampanel.