ERP sources in middle cingulate and precuneus differentiate Parkinson's patients from healthy controls and lingual gyri sources reflect human recombinant EPO effects in a Flanker task

We used EEG source analysis to identify which cortical areas were involved in the suppression of competing responses on a flanker task and compare the potential efficacy of recombinant-human erythropoietin (rHuEPO) in the performance of Parkinson9s Disease patients. The samples were 18 medicated PD patients (9 with rHuEPO and 9 without rHuEPO) and 9 age and education-matched healthy controls (HCs) who completed the flanker task with simultaneous EEG recordings. N1, N2 and P3 event-related potential (ERP) components were identified and a low-resolution tomography (LORETA) inverse solution was employed to localize the neural generators. Reaction times and errors were increased for the incongruent flankers for PD patients compared to controls. EEG source analysis identified an effect of rHuEPO on the lingual gyri for the early N1component. N2-related sources in middle cingulate and precuneus were associated with the inhibition of automatic responses evoked by incongruent stimuli differentiating PD and HCs. From our results the rHuEPO seems to mediate an effect on N1 sources in lingual gyri but not on behavioural performance. N2-related sources in middle cingulate and precuneus differentiated PD and HCs.