Effects of stimulus–response compatibility on inhibitory processes in Parkinson’s disease

Abstract

Parkinson's disease (PD) is a neurodegenerative basal ganglia disorder accompanied by deficits in cognitive functions. One important executive function is the inhibition of responses. Due to basal ganglia damage, processes related to the selection of response are also dysfunctional. However, the relevance of deficits in response selection to processes related to response inhibition in PD is not clear. In this study we examined these processes by means of event-related potentials (ERPs) in two Go/Nogo tasks. In one task the stimulus-response mapping was compatible and in the other task it was incompatible with the meaning of the stimuli. The behavioural results show that PD patients were unaffected in the compatible response inhibition task but encountered problems in the incompatible one. In the ERPs the N2, generally reflecting response selection, was delayed for the PD compared to the control group. This suggests that response selection is delayed in PD. Moreover, the N2 was specifically enhanced in Nogo trials. This indicates that premotor inhibition, which is probably reflected by the Nogo-N2, is intensified in PD. The P3 was specifically attenuated and delayed after Nogo stimuli in the incompatible condition for PDs. Assuming that the Nogo-P3 reflects the evaluation of successful motor inhibition, our data show that this process is attenuated and delayed in PD but mainly in the incompatible task. The results suggest that inhibitory deficits in PD are only evident in complex (incompatible) stimulus-response mappings. These effects are probably due to an overstrain of striatal processes.

Event-related potentials and cognition in Parkinson’s disease: An integrative review

“…Due to the usually large proportions of Go-trials, the participants develop a predominant tendency to respond that places high demands on executive processes of action restraint on NoGo-trials (Eigsti et al, 2006;Lange et al, 2014;Lange and Eggert, 2015). As displayed in Table 3, NoGo-P3 amplitudes were repeatedly reported to be attenuated in PD patients (Beste et al, 2009a;Bokura et al, 2005;Osawa et al, 2005;Pulvermüller et al, 1996; but see Beste et al, 2010). Note that Beste et al…”

Effects of Emotional Valence on Hemispheric Asymmetries in Response Inhibition

“…The earlier of the two components is the Nogo-N2, a negative component that is thought to reflect either pre-motor inhibition [32] or monitoring of response conflict [34]. The later of the two components is the Nogo-P3, a positive deflection that has been linked to the evaluation of successful inhibition, given that it peaks too late after the response to directly reflect inhibition processes [35][36][37][38].…”

Variations in theTNF-α Gene (TNF-α -308G→A) Affect Attention and Action Selection Mechanisms in a Dissociated Fashion

“…Action selection processes, which become increasingly important once stimulus identification processes are finished, are most likely reflected by another ERP, the N2 ERP-component (e.g., Beste et al 2008aBeste et al , 2009aBeste et al , 2010bGajewski et al 2008;Van Veen and Carter 2002;Willemssen et al 2009). WildWall et al (2008) showed that the N2 is usually small when stimulus-response mapping is easy, while it is enhanced when response selection is intensified due to a conflict occurring between intended and not intended responses (Folstein and Van Petten 2008;Van Veen and Carter 2002).…”