The Simon effect modulates N2cc and LRP but not the N2pc component

Previous studies have reported that the horizontal arrangement of the stimuli in Simon tasks elicits three different components: LRP, N2pc and N2cc. Although N2cc may play a key role in Simon tasks, as it is involved in preventing responses based on stimulus position, modulation of the N2cc componen...

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Detalhes bibliográficos
Autores: Cespón, Jesús, Galdo Álvarez, Santiago, Díaz Fernández, Fernando
Formato: artículo
Fecha de publicación:2012
País:España
Recursos:Universidad de Santiago de Compostela (USC)
Repositorio:Minerva. Repositorio Institucional de la Universidad de Santiago de Compostela
Idioma:inglés
OAI Identifier:oai:minerva.usc.gal:10347/46107
Acesso em linha:https://hdl.handle.net/10347/46107
Access Level:acceso abierto
Palavra-chave:Simon effect
Event-related potential
Spatial attention
Premotor cortexe
LORETA
Descrição
Resumo:Previous studies have reported that the horizontal arrangement of the stimuli in Simon tasks elicits three different components: LRP, N2pc and N2cc. Although N2cc may play a key role in Simon tasks, as it is involved in preventing responses based on stimulus position, modulation of the N2cc component according to the experimental conditions has not previously been investigated because of N2cc/LRP overlap in similar regions and temporal window. The aim of the present study was to investigate how the Simon effect modulates N2pc, N2cc and LRP components. For this purpose, participants were asked to respond to an arrow according to its colour. Three conditions, which depended on the congruency between stimulus position and the required response, were analysed: compatible position (CP), incompatible position (IP), and neutral position (NP). The LRP peak latency was delayed in IP with respect to CP and NP conditions. Lateralized minus neutral position (L – NP) subtractions were carried out to remove the common motor activity and isolate the N2cc and N2pc components in the lateralized conditions. The N2cc amplitude in L − NP waveforms was larger in IP than in CP, in accordance with the greater effort required to monitor selection of the correct response in the first condition. eLORETA analysis also revealed greater premotor activity at 150–200 ms in IP and CP, than in NP, which was attributed to the N2cc component present in IP/CP conditions. Evidence of functional dissociation between N2pc and N2cc components was obtained, because N2cc, but not N2pc, was affected by the experimental conditions