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The perception of the passing of time is fundamental to conscious experience. The duration of a sensory stimulus is one of its defining attributes, but it is not clear how this is encoded in the brain. This work explores whether the duration of a visual stimulus is an attribute that the brain can automatically adapt to and use to predict future stimulus durations. Visual mismatch negativity (vMMN) is an ERP component elicited, even when the stimuli are unattended, when an 'unexpected' visual stimulus appears amongst a series of expected stimuli in an 'oddball' paradigm. As such vMMN has been suggested to show that the violation of a pattern in a sequence has been automatically detected. To date, vMMN has only been measured to differences in the visual durations of static on/off stimuli, placed near to the centre of the visual field. Our study measures vMMN to test whether duration is encoded automatically for static stimuli against a blank background and moving stimuli against a static background, whilst attention is directed to a different spatial location using a continuous, attention demanding task. VMMN elicited in response to the shorter duration for both stimuli shows that the brain detects the differences of duration even in the absence of focussed spatial attention. For the motion stimulus a larger difference in duration was needed. We conclude that duration is encoded automatically in the visual cortex and is an attribute that can be adapted to, and form the basis of predictions., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The visual mismatch negativity (vMMN) component is regarded as a prediction error signal elicited by events violating the sequential regularities of environmental stimulation. The aim of the study was to investigate the effect of familiarity on the vMMN. Stimuli were patterns comprised of familiar (N) or unfamiliar (И) letters. In a passive oddball paradigm, letters (N and И) were presented as either standard or deviant in separate conditions. VMMNs emerged in both conditions; peak latency of vMMN was shorter to the И deviant compared to the vMMN elicited by the N deviant. To test the orientation-specific effect of the oblique lines on the vMMN, we introduced a control experiment. In the control experiment, the patterns were constructed solely from oblique lines, identical to the oblique lines of the N and И stimuli. Contrary to the first experiment, there was no significant difference between the vMNNs elicited by the two orientations. Therefore, the differences in vMMNs to И and N deviants are not attributable to the physical difference between the И and N stimuli. Consequently, the vMMN is sensitive to the familiarity of the stimuli. This article is part of a Special Issue entitled SI: Prediction and Attention., (Copyright © 2015. Published by Elsevier B.V.)

The aim of the study was to investigate the sensitivity of the visual mismatch negativity (vMMN) component of event-related potentials (ERPs) to the perceptual experience of brightness changes. The percept could be based on either real contrast or illusory brightness changes. In the illusory condition, we used Craik-Cornsweet-O׳Brien (CCOB) stimuli. CCOB stimuli comprised of grey, equiluminant areas and Cornsweet-edges that separated the areas. These specific edges, containing opposing darkening and ligthening gradients, modify the perceived brigthness of the flanking areas. Areas next to the darkening part (of the edges) perceived darker while areas next to the lightening part perceived lighter. Reversing the gradients induces illusory brigthness changes. The normal and reversed stimuli were delivered according to a passive oddball paradigm. In another condition (REAL condition), we used stimuli with real contrast difference. The perceived brightness of the stimuli applied in this sequence was fitted to the normal and reversed CCOB stimuli. In a third condition (CONTROL condition), we tested the ERP effect of the reversing of Cornsweet-edge. In this condition, the changes did not induce illusory brightness changes. We obtained vMMN with double peaks to both real and illusory brigthness changes, furthermore, no vMMN emerged in the CONTROL condition. vMMNs fell in the same latency range in the two conditions, nevertheless the components slightly differed in terms of scalp distribution. Since the perceptual experience (i.e. brightness changes) was similar in the two conditions, we argue that the vMMN is primarily sensitive to the perceptual experience and the physical attributes of the stimulation has only a moderate effect in the elicitation of the vMMN., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The automatic processing of deviances from the temporal context of the visual environment has become an important topic in visual cognitive sciences, which is often investigated using the visual mismatch negativity (vMMN). This event-related potential (ERP) component is elicited by an irregular stimulus (e.g., a red disc) presented in a series of stimuli (e.g., green discs) comprising a temporal regularity (e.g., colour repetition). We determined the influence of lower- vs. upper-hemifield presentation of the irregular stimulus on the vMMN while using whole-field stimulus displays controlling for sustained shifts in spatial attention. Deviances presented in the lower hemifield elicited a larger vMMN than the ones presented in the upper hemifield at a latency of 200-280ms. However, this asymmetry was preceded by deviance-related hemifield effects already emerging at an earlier latency (110-150ms), where upper-hemifield deviances elicited a positive potential but lower-hemifield deviances did not. With variable resolution electromagnetic tomography (VARETA) early deviance-related activity was localised to retinotopically organised regions of the visual cortex (BA 17/18) and vMMN-sources were localised to the middle/superior occipital gyrus, to higher areas along the temporal visual stream, but also to BA 17/18. We argue that the upper/lower-hemifield vMMN asymmetry relies at least partially on the hemifield-dependent differential sensitivity of early deviance-related activity generated in retinotopically organised regions of the visual cortex. However, a superior automatic processing of deviances presented in the lower visual hemifield may also contribute to the effect., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In a passive oddball task (performing in a video game), participants were presented with sequences of either standard stimuli or patterns containing deviant orientation, deviant spatial frequency or both deviant orientation and spatial frequency. Orientation deviants presented to the lower half of the visual field elicited a posterior negative component with a peak latency of 130 ms. Spatial frequency deviants elicited a similarly negative component that was later followed by another negative component. Activity elicited by the double-deviant stimulus was identical to activity elicited by the orientation deviant alone. The subtraction difference of the peak latency and scalp distribution of the deviant minus the standard difference potentials were unequal to those of the exogenous event-related potential (ERP) components and were therefore considered visual mismatch negativities (vMMNs). The non-additivity of the feature-related responses is interpreted as sensitivity of the implicit change-detection system to deviant events rather than an exclusive sensitivity to individual features. Deviant stimuli presented to the upper half of the field elicited responses with positive polarity, but this activity was less pronounced than the vMMN. Polarity reversal of the response to upper half-field stimulation suggests that the origin of the activity lies in retinotopic areas. Because of the emergence of a mismatch component with positive polarity, we propose that the term visual mismatch negativity (vMMN) be replaced with the more general term visual mismatch response (vMMR)., (Copyright © 2011 Elsevier B.V. All rights reserved.)

We studied whether, similarly to the auditory modality, short-period temporal integration processes occur in vision. Event-related potentials (ERP) were recorded for occasional stimulus omissions from sequences of patterned visual stimuli. A posterior negative component emerged only when the constant stimulus onset asynchrony (SOA) was shorter than 150 ms. This upper limit is comparable with the duration of the temporal window of integration observed in the auditory modality (including experiments studying the effects of stimulus omissions). Parameters of the posterior negativity were highly similar irrespective of whether the stimuli were task-relevant or not (Experiment 1). Thus, we identified this potential as the visual mismatch negativity (vMMN) component, which reflects task-independent detection of violating regularities of the stimulation. vMMN was followed by an anterior positivity (the P3a), indicating attentional shifts induced by the stimulus omissions. In Experiment 2, a posterior negativity similar to that observed in Experiment 1 emerged after the termination of short trains of stimuli, again only when the SOA was shorter than 150 ms. These results support the notion of a temporal integration window in the visual modality, the duration of which is between 150 and 180 ms.