Visual mismatch negativity (vMMN): Automatic detection change followed by an inhibition of the attentional switch without visual awareness

Attentional processing in the absence of conscious vision has yet to be understood in terms of neurophysiological mechanisms. Therefore, we used the visual mismatch negativity (vMMN) to determine if automatic detection of changes can be followed by an attentional switch without visual awareness. Random moving dots changing in direction were presented in the periphery, while participants carried out an effortful Stroop test in the central visual field to fully engage their attention on this primary task. The results revealed a posterior vMMN at 200 ms that was maximal in the parietal regions, revealing an automatic detection of change in the absence of visual awareness related to a dorsal/magnocellular pathway. Moreover, a frontal and central positivity, with a more pronounced activity in the left frontal areas was found at 300 ms possibly reflecting (1) unconscious attentional switch, (2) inhibition of explicit attentional switch by the left frontal areas acting on the right frontal areas via interhemispheric connections (3) inhibition of explicit attentional switch by the frontal areas acting on the central area via top-down connections. In conclusion, our results showed that vMMN could be a useful tool to study detection of changes and attentional mechanisms in the absence of visual consciousness.