Pre-conference workshop: Visual mismatch negativity
Tuesday, Sep 8, 2015
A form of visual mismatch negativity to color-deviant distractors disrupting visual search performance
1Neuroscience Center, a. Neuroscience Center, University of Helsinki, Finland. b.Center for Mind and Brain, University of CA, Davis, USA. c. Helsinki Collegium for Advanced Studies, University of Helsinki, Finland., Helsinki, Finland
2d. Cognitive Brain Research Unit, Institute of Behavioral Sciences, University of Helsinki, Finland, Germany
3e. Mental Health Research Center, Russian Academy of Medical Sciences. f. Center of Neurobiological Diagnostics, Moscow State University of Psychology and Education. g. Scientific and Practical Center of Child Psychiatry and Neurology, Moscow, Russia
4h. MEG Center, Moscow State University of Psychology and Education, Russia. i. Autism Research Laboratory, Moscow State University of Psychology and Education, Russia, Russia
When we close our eyes, we can actively envision what we have just seen, yet upon re-opening our eyes and searching the same visual scene, we paradoxically find features of the visual scene that we neither remember imagining nor even remember seeing in the first place. Visual search for a shape singleton was combined with a color oddball paradigm so as to investigate memory for to-be-ignored color. Color singleton distractor objects, when deviant in color elicited a color vMMN with a latency of 120–160 ms and a posterior distribution over the left hemisphere. That color deviance also slowed identification of a uniquely shaped visual target singleton, demonstrating that the deviance of to-be-ignored color singleton caused distraction.
Correlations revealed the amplitude of this color vMMN electrophysiologically indexed this behavioral distraction effect. The interval between visual scenes was longer than 600 ms, indicating that the brain's memory for the color of the preceding visual scenes persisted for at least 600 ms. Therefore, in the case of the neural code for color, without the requirement of actively attending or deliberately retaining the color of the color singleton distractor, durable memory representations are formed obligatorily.
In the light of this vMMN evidence, questioned is the received wisdom that i) visual search has no memory and ii) vision has no memory. Critically reconsidered rather are thus the corresponding concepts that i) visual search has a memory and ii) vision has a memory.