Colás, I. 1 , Capilla, A. 2 & Chica, A. B. 1
1 Centro de Invrestigación Mente, Cerebro y Comportamiento (CIMCYC) - Universidad de Granada
2 Universidad Autónoma de Madrid
The relationship between attention and consciousness has been a highly debated topic in Cognitive Neuroscience. Previous studies have shown that alerting and orienting attention networks modulate visual conscious perception, both at behavioral and neural levels (Chica et al., 2012, 2016). Regarding executive control, recent evidence has shown that conflict resolution on a Stroop task impacts participants' response criterion to detect near-threshold stimuli (Colás, Triviño & Chica, 2017). In the present study, we employed high-density electroencephalography (EEG) to investigate the neural basis of this behavioral interaction. Participants performed a Stroop task concurrently with a conscious detection task. We analyzed the N2 potential to the Stroop stimulus as a function of Stroop congruency (congruent or incongruent) and visual awareness of the near-threshold stimulus (seen or unseen). We also explored whether reactive and proactive mechanisms of control would impact conscious perception differently by manipulating the proportion of congruent and incongruent Stroop stimuli (De Pisapia & Braver, 2006). We found that this conflict-related N2 potential was modulated by conscious perception, as a larger N2 amplitude was observed for seen as compared to unseen stimuli. This effect was mostly associated with incongruent trials from the high proportion congruent condition, probably due to the implementation of reactive control mechanisms. A similar modulation was observed for congruent trials from the low proportion congruent condition. Therefore, this modulation of conscious perception on the N2 amplitude might be reflecting not only conflict resolution, but also unexpected (infrequent) stimulus-detection. Finally, source-localization analyses showed that the relationship between executive control and conscious perception lies in frontal lobe regions associated to conflict detection, such as the anterior cingulate cortex.