Visual mismatch negativity: New evidence from the equiprobable paradigm

Prioritization of social information processing: Eye gaze elicits earlier vMMN than arrows

Numerous research studies have demonstrated that eye gaze and arrows act as cues that automatically guide spatial attention. However, it remains uncertain whether the attention shifts triggered by these two types of stimuli vary in terms of automatic processing mechanisms. In our current investigation, we employed an equal probability paradigm to explore the likenesses and distinctions in the neural mechanisms of automatic processing for eye gaze and arrows in non-attentive conditions, using visual mismatch negative (vMMN) as an indicator of automatic processing. The sample size comprised 17 participants. The results indicated a significant interaction between time duration, stimulus material, and stimulus type. The findings demonstrated that both eye gaze and arrows were processed automatically, triggering an early vMMN, although with temporal variations. The vMMN for eye gaze occurred between 180 and 220 ms, whereas for arrows it ranged from 235 to 275 ms. Moreover, arrow stimuli produced a more pronounced vMMN amplitude. The earlier vMMN response to eye gaze compared with arrows implies the specificity and precedence of social information processing associated with eye gaze over the processing of nonsocial information with arrows. However, arrow could potentially elicit a stronger vMMN because of their heightened salience compared to the background, and the expansion of attention focusing might amplify the vMMN impact. This study offers insights into the similarities and differences in attention processing of social and non-social information under unattended conditions from the perspective of automatic processing.

Automatic sensory change processing in adults with attention deficit and hyperactivity disorder: a visual mismatch negativity study

In addition to higher-order executive functions, underlying sensory processing ability is also thought to play an important role in Attention-Deficit/Hyperactivity Disorder (AD/HD). An event-related potential feature, the mismatch negativity, reflects the ability of automatic sensory change processing and may be correlated with AD/HD symptoms and executive functions. This study aims to investigate the characteristics of visual mismatch negativity (vMMN) in adults with AD/HD. Twenty eight adults with AD/HD and 31 healthy controls were included in this study. These two groups were matched in age, IQ and sex. In addition, both groups completed psychiatric evaluations, a visual ERP task used to elicit vMMN, and psychological measures about AD/HD symptoms and day-to-day executive functions. Compared to trols, the late vMMN (230-330 ms) was significantly reduced in the AD/HD group. Correlation analyses showed that late vMMN was correlated with executive functions but not AD/HD symptoms. However, further mediation analyses showed that different executive functions had mediated the relationships between late vMMN and AD/HD symptoms. Our findings indicate that the late vMMN, reflecting automatic sensory change processing ability, was impaired in adults with AD/HD. This impairment could have negative impact on AD/HD symptoms via affecting day-to-day executive functions.

Rare incompatible stimuli evoke visual mismatch negativity in a flanker task

In the flanker task, the behavioral performance for incompatible stimuli is worse in the mostly compatible (rare) condition than in the equiprobable condition. Furthermore, incompatible stimuli evoke visual mismatch negativity (VMMN) when comparing the rare and equiprobable conditions. Compatible and incompatible stimuli differ in terms of their shape and type. This study aimed to examine whether VMMN evoked by rare incompatible stimuli were associated with the shape or type of the stimulus. In a modified version of the flanker task, stimuli were manipulated by two shapes (typical or peculiar) and two types (compatible or incompatible): typical compatible stimuli (< <  <  <  < and >  >  >  > >), typical incompatible stimuli (> >  <  >  > and <  <  >  < <), peculiar compatible stimuli (+ <  <  <  + and +  >  >  > +), and peculiar incompatible stimuli (+ >  <  >  + and +  <  >  < +). In the rare condition, typical incompatible, peculiar compatible, and peculiar incompatible stimuli were presented with a probability of 10%, whereas all the stimuli were presented equally in the equiprobable condition. Right posterior negativity from 200 to 250 ms was significantly more negative in the rare condition than in the equiprobable condition for typical and peculiar incompatible stimuli; however, this difference was not observed for peculiar compatible stimuli. VMMN was significantly more negative for typical and peculiar incompatible stimuli than for peculiar compatible stimuli, and was not significantly different between typical and peculiar incompatible stimuli. These findings suggest that VMMN for incompatible stimuli is associated with the type rather than the shape of the stimulus.

Perceptual Expectations Are Reflected by Early Alpha Power Reduction

The predictability of a stimulus can be characterized by its transitional probability. Perceptual expectations derived from the transitional probability of the stimulus were found to modulate the early alpha oscillations in the sensory regions of the brain when neural responses to expected versus unexpected stimuli were compared. The objective of our study was to find out the extent to which this low-frequency oscillation reflects stimulus predictability. We aimed to detect the alpha-power difference with smaller differences in transitional probabilities by comparing expected stimuli with neutral ones. We studied the effect of expectation on perception by applying an unsupervised visual statistical learning paradigm with expected and neutral stimuli embedded in an image sequence while recording EEG. Time-frequency analysis showed that expected stimuli elicit lower alpha power in the window of 8-12 Hz and 0-400 msec after stimulus presentation, appearing in the centroparietal region. Comparing previous findings of expectancy-based alpha-band modulation with our results suggests that early alpha oscillation shows an inverse relationship with stimulus predictability. Although current data are insufficient to determine the origin of the alpha power reduction, this could be a potential sign of expectation suppression in cortical oscillatory activity.

Orientation and contrast deviance examined: Contrast effects mimic deviant-related negativity yet neither produce the canonical neural correlate of prediction error

The visual mismatch negativity (vMMN) is a negative-going event-related potential (ERP) component that is largest somewhere between 100 and 300 ms after the onset of an unpredictable visual event (i.e., a deviant) in an otherwise predictable sequence of visual events (i.e., standards). Many have argued that the vMMN allows us to monitor our ever-changing visual environment for deviants critical to our survival. Recently, however, it has become unclear whether unpredicted changes in low-level features of visual input, like orientation, can evoke the vMMN. I address this by testing isolated orientation changes, to confirm recent findings, and isolated contrast changes, to determine whether other low-level features of visual input do not evoke the vMMN in a traditional oddball paradigm. Eighteen participants saw sequences of rare, unanticipated, and different deviant stimuli, interspersed among frequent, anticipated, and identical standard stimuli. Stimuli were Gabor patches. Neither deviant produced a vMMN. Therefore, changes in low-level visual properties of well-controlled stimuli-a stimulus in which one property can be manipulated while all others remain unaffected-like Gabor patches do not yield a vMMN.

Automatic Change Detection in Interwoven Sequences: A Visual Mismatch Negativity Study

In this study, we investigated whether the cognitive system, known to be able to register regular visual event sequences and the violation of these sequences automatically, had the capacity of processing two sequences simultaneously. To this end, we measured the visual mismatch negativity (vMMN) component of ERPs as interwoven event sequences simultaneously presented to the left and right side of the screen. One of the sequences consisted of geometric patterns (diamonds); the other, photographs of human faces. In successive cycles, parts of the stimuli vanished and then re-appeared (the OFF/ON method). The vanishing parts served as either standard (frequently vanishing parts) or infrequent (deviant) events, but these events were task-irrelevant. The 20 adult participants (age 21.40 ± 2.72 years) performed a visual tracking task, with the OFF/ON task being a passive oddball paradigm. According to the results, both OFF and ON events, and both diamond and face stimuli elicited the vMMN component, showing that the system underlying this activity is capable of processing two event sequences if the sequences consist of fairly different kind of objects as stimuli. The sLORETA analysis showed that the source of vMMN was more frequent contralaterally to the deviant event, and the sources comprised loci from ventral and dorsal structures, as well as some anterior loci.

Contingency learning on the proportional congruency effect of the Stroop task is manifest in deviant processing

OBJECTIVE

The proportion congruency effect has been reported in interference tasks. The mostly congruent block is the frequent condition, and the mostly incongruent block is the rare condition for congruent stimuli, whereas the mostly congruent block is the rare condition, and the mostly incongruent block is the frequent condition for incongruent stimuli. This study examined the cognitive mechanism underlying the proportion congruency effect in the two-choice Stroop task using event-related potential components related to deviant processing.

METHOD

Stimuli were Kanji characters meaning 'red' and 'blue' painted by congruent and incongruent colors. Participants were required to provide a two-choice button-press response corresponding to the colors. The congruent and incongruent stimuli were presented on rare (20%) and frequent (80%) conditions.

RESULTS

N1 was enhanced in the rare condition relative to the frequent condition for both congruent and incongruent stimuli. The results suggested that colors and characters were not processed independently in the N1 time range, which made selective attention to the relevant feature difficult. Posterior negativity from 200 to 250 ms was also different between rare and frequent conditions, indicating the presence of visual mismatch negativity for congruent and incongruent stimuli. It was considered that the distinction between congruent and incongruent stimuli was evident in mostly incongruent blocks, indicating that the selective attention mechanism was not actively engaged.

CONCLUSION

The proportion congruency effect was explained by contingency learning rather than selective attention in the present task. The cognitive mechanisms underlying the proportion congruency effect are reflected by deviant event-related potential components.

Stimulus expectations do not modulate visual event-related potentials in probabilistic cueing designs

Humans and other animals can learn and exploit repeating patterns that occur within their environments. These learned patterns can be used to form expectations about future sensory events. Several influential predictive coding models have been proposed to explain how learned expectations influence the activity of stimulus-selective neurons in the visual system. These models specify reductions in neural response measures when expectations are fulfilled (termed expectation suppression) and increases following surprising sensory events. However, there is currently scant evidence for expectation suppression in the visual system when confounding factors are taken into account. Effects of surprise have been observed in blood oxygen level dependent (BOLD) signals, but not when using electrophysiological measures. To provide a strong test for expectation suppression and surprise effects we performed a predictive cueing experiment while recording electroencephalographic (EEG) data. Participants (n=48) learned cue-face associations during a training session and were then exposed to these cue-face pairs in a subsequent experiment. Using univariate analyses of face-evoked event-related potentials (ERPs) we did not observe any differences across expected (90% probability), neutral (50%) and surprising (10%) face conditions. Across these comparisons, Bayes factors consistently favoured the null hypothesis throughout the time-course of the stimulus-evoked response. When using multivariate pattern analysis we did not observe above-chance classification of expected and surprising face-evoked ERPs. By contrast, we found robust within- and across-trial stimulus repetition effects. Our findings do not support predictive coding-based accounts that specify reduced prediction error signalling when perceptual expectations are fulfilled. They instead highlight the utility of other types of predictive processing models that describe expectation-related phenomena in the visual system without recourse to prediction error signalling.

Attention is required for canonical brain signature of prediction error despite early encoding of the stimuli

Prediction error is a basic component of predictive-coding theory of brain processing. According to the theory, each stage of brain processing of sensory information generates a model of the current sensory input; subsequent input is compared against the model and only if there is a mismatch, a prediction error, is further processing performed. Recently, Smout and colleagues found that a signature of prediction error, the visual (v) mismatch negativity (MMN), for a fundamental property of visual input-its orientation-was absent without endogenous attention on the stimuli. This is remarkable because the weight of evidence for MMNs from audition and vision is that they occur without endogenous attention. To resolve this discrepancy, we conducted an experiment addressing 2 alternative explanations for Smout and colleagues' finding: that it was from a lack of reproducibility or that participants' visual systems did not encode the stimuli when attention was on something else. We conducted a similar experiment to that of Smout and colleagues. We showed 21 participants sequences of identically oriented Gabor patches, standards, and, unpredictably, otherwise identical, Gabor patches differing in orientation by ±15°, ±30°, and ±60°, deviants. To test whether participants encoded the orientation of the standards, we varied the number of standards preceding a deviant, allowing us to search for a decrease in activity with the number of repetitions of standards-repetition suppression. We diverted participants' attention from the oriented stimuli with a central, letter-detection task. We reproduced Smout and colleagues' finding of no vMMN without endogenous attention, strengthening their finding. We found that our participants showed repetition suppression: They did encode the stimuli preattentively. We also found early processing of deviants. We discuss various explanations why the earlier processing did not extend into the vMMN time window, including low precision of prediction.

The role of attention control in visual mismatch negativity (vMMN) studies

The detection of unattended visual changes is investigated by the visual mismatch negativity (vMMN) component of event-related potentials (ERPs). The vMMN is measured as the difference between the ERPs to infrequent (deviant) and frequent (standard) stimuli irrelevant to the ongoing task. In the present study, we used human faces expressing different emotions as deviants and standards. In such studies, participants perform various tasks, so their attention is diverted from the vMMN-related stimuli. If such tasks vary in their attentional demand, they might influence the outcome of vMMN studies. In this study, we compared four kinds of frequently used tasks: (1) a tracking task that demanded continuous performance, (2) a detection task where the target stimuli appeared at any time, (3) a detection task where target stimuli appeared only in the inter-stimulus intervals, and (4) a task where target stimuli were members of the stimulus sequence. This fourth task elicited robust vMMN, while in the other three tasks, deviant stimuli elicited moderate posterior negativity (vMMN). We concluded that the ongoing task had a marked influence on vMMN; thus, it is important to consider this effect in vMMN studies.

How salience enhances inhibitory control: An analysis of electro-cortical mechanisms

Stop-signal tasks (SSTs) combined with human electro-cortical recordings (Event-Related Potentials, ERPs) have revealed mechanisms associated with successful stopping (relative to failed), presumably contributing to inhibitory control. The corresponding ERP signatures have been labeled stop N1 (+/- 100-ms latency), stop N2 (200 ms), and stop P3 (160-250 ms), and argued to reflect more sensory-specific (N1) versus more generic (N2, P3) mechanisms. However, stop N1 and stop N2, as well as latencies of stop-P3, appear to be quite inconsistent across studies. The present work addressed the possible influence of stop-signal salience, expecting high salience to induce clear stop N1s but reduced stop N2s, and short-latency stop P3s. Three SST varieties were combined with high-resolution EEG. An imperative visual (go) stimulus was occasionally followed by a subsequent (stop) stimulus that signalled to withhold the just initiated response. Stop-Signal Reaction Times (SSRTs) decreased linearly from visual-low to visual-high-salience to auditory. Auditory Stop N1 was replicated. A C1-like visual evoked potential (latency < 100 ms) was observed only with high salience, but not robustly associated with successful versus failed stops. Using the successful-failed contrast a visual stop-N1 analogue (112-156 ms post-stop-signal) was identified, as was right-frontal stop N2, but neither was sensitive to salience. Stop P3 had shorter latency for high than for low salience, and the extent of the early high-salience stop P3 correlated inversely with SSRT. These results suggest that salience-enhanced inhibitory control as manifest in SSRTs is associated with generic rather than sensory-specific electrocortical mechanisms.

Theta phase coherence in visual mismatch responses involved in access processing to visual awareness

Introduction: The electroencephalographic brain response to a deviation from the preceding sequential regularity of visual events, called visual mismatch negativity (vMMN), is well known to reflect automatic visual change detection. Our preliminary study showed a significant correlation between the enhancement of the vMMN amplitude and facilitation of perceptual alternation in binocular rivalry when the deviant stimulus was presented unconsciously. This implies that the vMMN is relevant to access processing, in which the unconscious stimulus is consciously perceived. Recent studies have reported that theta band oscillation evoked by a deviant stimulus is involved in evoking vMMN. However, it has not been clarified whether theta band oscillation associated with vMMN is also relevant to access processing. Methods: We analyzed the correlations between event-related spectral perturbation (ERSP) and inter-trial phase coherence (ITPC) in the theta band and the proportion of perceptual alternation from before to after the presentation of deviation in the same experimental paradigm as in our previous study. Results: We found that an increase in ITPC in the theta band tended to correlate with facilitation of perceptual alternation in binocular rivalry when the deviant was presented unconsciously, but there was no significant correlation in ERSP. Discussion: The results suggest that theta phase coherence underlying the visual mismatch process is relevant to the access processing.

Automatic change detection: Mismatch negativity and the now-classic Rensink, O’Reagan, and Clark (1997) stimuli

Change blindness experiments had demonstrated that detection of significant changes in natural images is extremely difficult when brief blank fields are placed between alternating displays of an original and a modified scene. On the other hand, research on the visual mismatch negativity (vMMN) component of the event-related potentials (ERPs) identified sensitivity to events (deviants) different from the regularity of stimulus sequences (standards), even if the deviant and standard events are non-attended. The present study sought to investigate the apparent controversy between the experience under the change blindness paradigm and the ERP results. To this end, the stimulus of Rensink, O’Reagen, and Clark (1997) was adapted to a passive oddball ERP paradigm to investigate the underlying processing differences between the standard (original) and deviant (altered) stimuli measured in 22 subjects. Posterior negativity within the 280–330 ms latency range emerged as the difference between ERPs elicited by standard and deviant stimuli, identified as visual mismatch negativity (vMMN). These results raise the possibility that change blindness is not based on the lack of detailed visual representations or the deficiency of comparing two representations. However, effective discrimination of the two scene versions requires considerable frequency differences between them.

Research on Effective Recognition of Alarm Signals in Human-Machine System Based on Cognitive Neural Experiments

The reasonable design of the alarm signal in the man-machine system is one of the important factors that determine the occurrence of safety accidents. Neuroergonomics provides a new perspective for the study of the cognitive process of alarm signals, which can reveal the mechanism of human perception of visual alarm signals from the cognitive level of the brain, thereby identifying the effectiveness of alarm signals. The article's research simulated the human-machine system for heat dissipation of new energy vehicles, used the automatic control interface of the cooling water system as the stimulus material, and used the event-related potential technology in cognitive neuroscience for experimental verification. The experimental results showed that: three kinds of alarm signals (color, color + shape, color + orientation) all induce visual mismatch waves, and the effective response of human to the alarm signal is color + orientation, color + shape, color from small to large, which provides a reference for the design of the alarm signal of the man-machine system.

The impact of musical training in symbolic and non-symbolic audiovisual judgements of magnitude

Quantity estimation can be represented in either an analog or symbolic manner and recent evidence now suggests that analog and symbolic representation of quantities interact. Nonetheless, those two representational forms of quantities may be enhanced by convergent multisensory information. Here, we elucidate those interactions using high-density electroencephalography (EEG) and an audiovisual oddball paradigm. Participants were presented simultaneous audiovisual tokens in which the co-varying pitch of tones was combined with the embedded cardinality of dot patterns. Incongruencies were elicited independently from symbolic and non-symbolic modality within the audio-visual percept, violating the newly acquired rule that “the higher the pitch of the tone, the larger the cardinality of the figure.” The effect of neural plasticity in symbolic and non-symbolic numerical representations of quantities was investigated through a cross-sectional design, comparing musicians to musically naïve controls. Individual’s cortical activity was reconstructed and statistically modeled for a predefined time-window of the evoked response (130–170 ms). To summarize, we show that symbolic and non-symbolic processing of magnitudes is re-organized in cortical space, with professional musicians showing altered activity in motor and temporal areas. Thus, we argue that the symbolic representation of quantities is altered through musical training.

Processing Self-Related Information Under Non-attentional Conditions Revealed by Visual MMN

Mismatch negativity (MMN) of event-related potentials (ERPs) is a biomarker reflecting the preattentional change detection under non-attentional conditions. This study was performed to explore whether high self-related information could elicit MMN in the visual channel, indicating the automatic processing of self-related information at the preattentional stage. Thirty-five participants were recruited and asked to list 25 city names including the birthplace. According to the difference of relevance reported from the participants, we divided names of the different cities into high (birthplace as deviants), medium (Xi’an, where participants’ university is located, as deviants), and low (totally unrelated cities as standard stimuli) self-related information. Visual MMN (vMMN) was elicited by high self-related information but not by medium self-related information, with an occipital–temporal scalp distribution, indicating that, under non-attentional condition, high self-related information can be effectively processed automatically in the preattentional stage compared with low self-related information. These data provided new electrophysiological evidence for self-related information processing.

The Neural Responses of Visual Complexity in the Oddball Paradigm: An ERP Study

This research measured human neural responses to images of different visual complexity levels using the oddball paradigm to explore the neurocognitive responses of complexity perception in visual processing. In the task, 24 participants (12 females) were required to react to images with high complexity for all stimuli. We hypothesized that high-complexity stimuli would induce early visual and attentional processing effects and may elicit the visual mismatch negativity responses and the emergence of error-related negativity. Our results showed that the amplitude of P1 and N1 were unaffected by complexity in the early visual processing. Under the target stimuli, both N2 and P3b components were reported, suggesting that the N2 component was sensitive to the complexity deviation, and the attentional processing related to complexity may be derived from the occipital zone according to the feature of the P3b component. In addition, compared with the low-complexity stimulus, the high-complexity stimulus aroused a larger amplitude of the visual mismatch negativity. The detected error negativity (Ne) component reflected the error detection of the participants’ mismatch between visual complexity and psychological expectations.

Visual Mismatch Negativity Reflects Enhanced Response to the Deviant: Evidence From Event-Related Potentials and Electroencephalogram Time-Frequency Analysis

Automatic detection of information changes in the visual environment is crucial for individual survival. Researchers use the oddball paradigm to study the brain’s response to frequently presented (standard) stimuli and occasionally presented (deviant) stimuli. The component that can be observed in the difference wave is called visual mismatch negativity (vMMN), which is obtained by subtracting event-related potentials (ERPs) evoked by the deviant from ERPs evoked by the standard. There are three hypotheses to explain the vMMN. The sensory fatigue (or refractoriness) hypothesis considers that weakened neural activity caused by repetition results in decreased ERPs of the standard. The memory trace hypothesis proposes that vMMN results from increased responses to the deviant. The predictive coding hypothesis attributes the difference to enhanced responses for deviants and suppression for standards. However, when distinguishing between these effects, previous researchers did not consider the effect of low-level features on the vMMN. In this experiment, we used face sequences composed of different emotions (e.g., neutral and fearful face) and presented an oddball sequence, a reverse oddball sequence, and an equiprobable sequence to participants. The deviant of the oddball sequence was subtracted from the standard of the oddball sequence, the reverse oddball sequence, and the same type of stimulus of the equiprobable sequence to get oddball-vMMN (vMMN1), reverse oddball-vMMN (vMMN2), and equiprobable-vMMN (vMMN3), respectively. The results showed no significant difference between vMMN2 and vMMN3 in 100–350 ms following stimulus onset, while the vMMN effect was significant, indicating that the probability of the standard did not affect vMMN, which supported the memory trace hypothesis. Additionally, the fearful-related vMMN were more negative than the neutral-related vMMN within the range of 100–150 ms, suggesting a negative bias. We analyzed the source location of different vMMNs. There was no significant difference in brain regions between different vMMNs. Time-frequency analysis showed that the deviant had stronger theta-band oscillatory than the standard (visual mismatch oscillatory responses, vMORs). However, there was no difference between vMORs2 and vMORs3, indicating that vMORs reflect an enhanced response to the deviant in terms of neural oscillation, supporting the memory trace hypothesis.

Event-related potentials evidence for long-term audiovisual representations of phonemes in adults

The presence of long-term auditory representations for phonemes has been well-established. However, since speech perception is typically audiovisual, we hypothesized that long-term phoneme representations may also contain information on speakers' mouth shape during articulation. We used an audiovisual oddball paradigm in which, on each trial, participants saw a face and heard one of two vowels. One vowel occurred frequently (standard), while another occurred rarely (deviant). In one condition (neutral), the face had a closed, non-articulating mouth. In the other condition (audiovisual violation), the mouth shape matched the frequent vowel. Although in both conditions stimuli were audiovisual, we hypothesized that identical auditory changes would be perceived differently by participants. Namely, in the neutral condition, deviants violated only the audiovisual pattern specific to each block. By contrast, in the audiovisual violation condition, deviants additionally violated long-term representations for how a speaker's mouth looks during articulation. We compared the amplitude of mismatch negativity (MMN) and P3 components elicited by deviants in the two conditions. The MMN extended posteriorly over temporal and occipital sites even though deviants contained no visual changes, suggesting that deviants were perceived as interruptions in audiovisual, rather than auditory only, sequences. As predicted, deviants elicited larger MMN and P3 in the audiovisual violation compared to the neutral condition. The results suggest that long-term representations of phonemes are indeed audiovisual.

Fronto-occipital mismatch responses in pre-attentive detection of visual changes: Implication on a generic brain network underlying Mismatch Negativity (MMN)

Current theories of pre-attentive change detection suggest a regularity or prediction violation mechanism involving a frontotemporal network. Modulations of the early inferior frontal cortex (IFC) mismatch response representing the effort in comparing a stimulus to the prediction, the superior temporal cortex (STC) response indicating deviance detection, and the late IFC response representing prediction model updating were consistently demonstrated in auditory change detection using event-related optical signal (EROS). If the prediction violation hypothesis is universal, a generic neural mechanism should be found in all sensory modalities. We postulated a generic fronto-sensory cortical network underlying the prediction violation mechanism: the IFC is responsible for non-modality-specific prediction processes while the sensory cortices are responsible for modality-specific error signal generation process. This study examined the involvement of the IFC-occipital cortex (OC) network in visual pre-attentive change detection. The EROS mismatch responses to deviant bar arrays violating a fixed orientation regularity (low in regularity abstractness) were compared to that of deviant violating a rotational orientation regularity (high in abstractness) while the information available for establishing the prediction model was manipulated by varying the number of standards preceding the deviants. Modulations of the IFCOC mismatch response patterns by abstractness and train length reflected the processing demands on the prediction processes and were similar to that of the IFC-STC network in auditory change detection. These findings demonstrated that the fronto-sensory cortical network is not unique to auditory pre-attentive change detection and provided supports for a universal neural mechanism across sensory modalities as suggested by the prediction violation hypothesis.

Involvement of Visual Mismatch Negativity in Access Processing to Visual Awareness

Psychophysiological studies with electroencephalography, focusing on the dynamical aspect of neural correlate of consciousness, reported that visual awareness negativity and P3 enhancement are observed at a latency, 200–300 ms after the visual stimulus onset, when the visual stimulus is consciously perceived. However, access processing to visual awareness (APVA) immediately before conscious perception still remains at the earlier stage of visual sensory processing, though there is little known regarding this subject. The present study hypothesized that visual mismatch negativity (vMMN), which reflects automatic change detection at a latency of 130–250 ms, might be involved in the APVA. In a previous study, vMMN was reported to be evoked by the deviant stimulus that is not consciously perceived in binocular rivalry. To clarify whether the visual change detection affects APVA, we conducted a modified experiment of oddball paradigm on binocular rivalry. The results showed a significant correlation between enhancement of vMMN amplitude and facilitation of perceptual alternation when the unconscious deviant was presented. This implies that vMMN is relevant to the APVA, which is a novel role of vMMN. In early visual processing, the attentional mechanism associated with vMMN is suggested to play an important role in unconscious neural processing at an earlier stage of visual awareness.

Auditory, Visual, and Cross-Modal Mismatch Negativities in the Rat Auditory and Visual Cortices

When the brain tries to acquire an elaborate model of the world, multisensory integration should contribute to building predictions based on the various pieces of information, and deviance detection should repeatedly update these predictions by detecting “errors” from the actual sensory inputs. Accumulating evidence such as a hierarchical organization of the deviance-detection system indicates that the deviance-detection system can be interpreted in the predictive coding framework. Herein, we targeted mismatch negativity (MMN) as a type of prediction-error signal and investigated the relationship between multisensory integration and MMN. In particular, we studied whether and how cross-modal information processing affected MMN in rodents. We designed a new surface microelectrode array and simultaneously recorded visual and auditory evoked potentials from the visual and auditory cortices of rats under anesthesia. Then, we mapped MMNs for five types of deviant stimuli: single-modal deviants in (i) the visual oddball and (ii) auditory oddball paradigms, eliciting single-modal MMN; (iii) congruent audio-visual deviants, (iv) incongruent visual deviants, and (v) incongruent auditory deviants in the audio-visual oddball paradigm, eliciting cross-modal MMN. First, we demonstrated that visual MMN exhibited deviance detection properties and that the first-generation focus of visual MMN was localized in the visual cortex, as previously reported in human studies. Second, a comparison of MMN amplitudes revealed a non-linear relationship between single-modal and cross-modal MMNs. Moreover, congruent audio-visual MMN exhibited characteristics of both visual and auditory MMNs—its latency was similar to that of auditory MMN, whereas local blockage of N-methyl-D-aspartic acid receptors in the visual cortex diminished it as well as visual MMN. These results indicate that cross-modal information processing affects MMN without involving strong top-down effects, such as those of prior knowledge and attention. The present study is the first electrophysiological evidence of cross-modal MMN in animal models, and future studies on the neural mechanisms combining multisensory integration and deviance detection are expected to provide electrophysiological evidence to confirm the links between MMN and predictive coding theory.

Impaired Audiovisual Representation of Phonemes in Children with Developmental Language Disorder

We examined whether children with developmental language disorder (DLD) differed from their peers with typical development (TD) in the degree to which they encode information about a talker’s mouth shape into long-term phonemic representations. Children watched a talker’s face and listened to rare changes from [i] to [u] or the reverse. In the neutral condition, the talker’s face had a closed mouth throughout. In the audiovisual violation condition, the mouth shape always matched the frequent vowel, even when the rare vowel was played. We hypothesized that in the neutral condition no long-term audiovisual memory traces for speech sounds would be activated. Therefore, the neural response elicited by deviants would reflect only a violation of the observed audiovisual sequence. In contrast, we expected that in the audiovisual violation condition, a long-term memory trace for the speech sound/lip configuration typical for the frequent vowel would be activated. In this condition then, the neural response elicited by rare sound changes would reflect a violation of not only observed audiovisual patterns but also of a long-term memory representation for how a given vowel looks when articulated. Children pressed a response button whenever they saw a talker’s face assume a silly expression. We found that in children with TD, rare auditory changes produced a significant mismatch negativity (MMN) event-related potential (ERP) component over the posterior scalp in the audiovisual violation condition but not in the neutral condition. In children with DLD, no MMN was present in either condition. Rare vowel changes elicited a significant P3 in both groups and conditions, indicating that all children noticed auditory changes. Our results suggest that children with TD, but not children with DLD, incorporate visual information into long-term phonemic representations and detect violations in audiovisual phonemic congruency even when they perform a task that is unrelated to phonemic processing.

Evaluating the evidence for expectation suppression in the visual system

Reports of expectation suppression have shaped the development of influential predictive coding-based theories of visual perception. However recent work has highlighted confounding factors that may mimic or inflate expectation suppression effects. In this review, we describe four confounds that are prevalent across experiments that tested for expectation suppression: effects of surprise, attention, stimulus repetition and adaptation, and stimulus novelty. With these confounds in mind we then critically review the evidence for expectation suppression across probabilistic cueing, statistical learning, oddball, action-outcome learning and apparent motion designs. We found evidence for expectation suppression within a specific subset of statistical learning designs that involved weeks of sequence learning prior to neural activity measurement. Across other experimental contexts, whereby stimulus appearance probabilities were learned within one or two testing sessions, there was inconsistent evidence for genuine expectation suppression. We discuss how an absence of expectation suppression could inform models of predictive processing, repetition suppression and perceptual decision-making. We also provide suggestions for designing experiments that may better test for expectation suppression in future work.

Automatic detection of peripheral stimuli in shooters and handball players: an event-related potential study

This study examined the practice-related sensitivity of automatic change detection. The visual mismatch negativity (vMMN) component of event-related potentials was compared in handball players and in sport shooters. Whereas effective performance in handball requires processing of a wide visual field, effective performance in shooting requires concentration to a narrow field. Thus, we hypothesized larger sensitivity to peripheral stimuli violating the regularity of sequential stimulation in handball players. Participants performed a tracking task, while task-irrelevant checkerboard patterns (a frequent and an infrequent type) were presented in the lateral parts of the visual field. We analyzed the vMMN, a signature of automatic detection of violating sequential regularity, and sensory components (P1, N1, and P2). We obtained larger vMMN in the handball players' group indicating larger sensitivity to peripheral stimuli. These results suggest the plasticity of the automatic visual processing, i.e., it can adapt to sport-specific demands, and this can be captured even in a short experimental session in the laboratory.

Pre-attentive Visual Processing in Alzheimer's Disease: An Event-related Potential Study

INTRODUCTION

While identifying Alzheimer's Disease (AD) in its early stages is crucial, traditional neuropsychological tests tend to lack sensitivity and specificity for its diagnosis. Neuropsychological studies have reported visual processing deficits of AD, and event-related potentials (ERPs) are suitable to investigate pre-attentive processing with superior temporal resolution.

OBJECTIVE

This study aimed to investigate visual attentional characteristics of adults with AD, from pre-attentive to attentive processing, using a visual oddball task and ERPs.

METHODS

Cognitively normal elderly controls (CN) and patients with probable AD (AD) were recruited. Participants performed a three-stimulus visual oddball task and were asked to press a designated button in response to the target stimuli. The amplitudes of 4 ERPs were analyzed. Mismatchnegativity (vMMN) was analyzed around the parieto-occipital and temporo-occipital regions. P3a was analyzed around the fronto-central regions, whereas P3b was analyzed around the centro-parietal regions.

RESULTS

Late vMMN amplitudes of the AD group were significantly smaller than those of the CN group, while early vMMN amplitudes were comparable. Compared to the CN group, P3a amplitudes of the AD group were significantly smaller for the infrequent deviant stimuli, but the amplitudes for the standard stimuli were comparable. Lastly, the AD group had significantly smaller P3b amplitudes for the target stimuli compared to the CN group.

CONCLUSION

Our findings imply that AD patients exhibit pre-attentive visual processing deficits, known to affect later higher-order brain functions. In a clinical setting, the visual oddball paradigm could be used to provide helpful diagnostic information since pre-attentive ERPs can be induced by passive exposure to infrequent stimuli.

Emotional visual mismatch negativity: a joint investigation of social and non-social dimensions in adults with autism

Unusual behaviors and brain activity to socio-emotional stimuli have been reported in Autism Spectrum Disorder (ASD). Atypical reactivity to change and intolerance of uncertainty are also present, but little is known on their possible impact on facial expression processing in autism. The visual mismatch negativity (vMMN) is an electrophysiological response automatically elicited by changing events such as deviant emotional faces presented among regular neutral faces. While vMMN has been found altered in ASD in response to low-level changes in simple stimuli, no study has investigated this response to visual social stimuli. Here two deviant expressions were presented, neutral and angry, embedded in a sequence of repetitive neutral stimuli. vMMN peak analyses were performed for latency and amplitude in early and late time windows. The ASD group presented smaller amplitude of the late vMMN to both neutral and emotional deviants compared to the typically developed adults (TD) group, and only the TD group presented a sustained activity related to emotional change (i.e., angry deviant). Source reconstruction of the vMMNs further revealed that any change processing elicited a reduced activity in ASD group compared to TD in the saliency network, while the specific processing emotional change elicited activity in the temporal region and in the insula. This study confirms atypical change processing in ASD and points to a specific difficulty in the processing of emotional changes, potentially playing a crucial role in social interaction deficits. Nevertheless, these results require to be further replicated with a greater sample size and generalized to other emotional expressions.

Selective Impairment of Processing Task-Irrelevant Emotional Faces in Cerebral Small Vessel Disease Patients

BACKGROUND

Few reports have implied electrophysiological alterations and neurocognitive abnormalities in patients with cerebral small vessel disease (CSVD), while no investigation is available regarding emotional processing. In the present study, pre-attentive processing of facial expressions was compared between CSVD sufferers and healthy controls using expression-related visual mismatch negativity (EMMN) as the indicator.

METHODS

A total of 22 CSVD patients (12 males) and 21 age-matched healthy controls (12 males) were recruited for neuropsychological and emotional assessments, as well as electroencephalogram recording and analysis. We employed an expression-related oddball paradigm to investigate automatic emotional processing, and a series of schematic emotional faces (neutral, happy, sad) unrelated to subject's task were present in the test to avoid low-level processing of facial features.

RESULTS

Although the distinctions of neuropsychological (MoCA and MMSE), emotional (GAD-7 and PHQ-9) and behavioral parameters (reaction time to target stimuli and response accuracy) did not reach significant levels, mean amplitudes of sad EMMN in time intervals of 150-250 ms and 250-350 ms were remarkably reduced in CSVD patients compared with healthy controls, but not for happy EMMN. Furthermore, in the control group, sad EMMN was demonstrated to be larger (more negative) than happy EMMN, while this interesting phenomenon disappeared in the CSVD group.

CONCLUSION

Our findings confirmed selective impairment of processing expressions which were task-irrelevant in CSVD patients, without the existence of negative bias (sad superiority) effect. The efficacy of EMMN as an electrophysiological evaluation marker of CSVD should be taken into account in future investigations.

Visual mismatch negativity elicited by semantic violations in visual words

The remarkable rapidity and effortlessness of speech perception and word reading by skilled listeners or readers suggest implicit or automatic mechanisms underlying language processing. In speech perception, the implicit mechanisms are reflected by the auditory mismatch negativity (MMN) response, suggesting that phonemic, lexical, semantic, and syntactic information are automatically and rapidly processed in the absence of focused attention. In visual word reading, implicit orthographic and lexical processing are reflected by visual mismatch negativity (vMMN), the visual counterpart of auditory MMN. The semantic processing of spoken words is reflected by MMN. This study investigated whether semantic processing is also reflected by vMMN. For this purpose, visual Chinese words belonging to different semantic categories (color, taste, and action) were presented to participants in oddball paradigms. A set of words belonging to the same semantic category was frequently presented as standards; a word belonging to a different semantic category was presented sporadically as deviant. Participants were instructed to perform a visual cross-change detection task and ignore the words. Significant vMMN was elicited in Experiments 1 to 3, in which the deviant word carried a semantic radical that overtly indicated the word's semantic category information. The vMMNs were most prominent around 260 ms after word onset, were parieto-occipital distributed, and were significantly left-hemisphere lateralized, suggesting rapid semantic processing of the visual words' category-related information. No significant vMMN was elicited in Experiment 4, in which the deviant word did not carry any semantic radicals. Thus, the semantic radical, which has a high frequency of occurrence because it is carried by many words, may be critical for the elicitation of vMMN.

Visual mismatch responses index surprise signalling but not expectation suppression

The ability to distinguish between commonplace and unusual sensory events is critical for efficient learning and adaptive behaviour. This has been investigated using oddball designs in which sequences of often-appearing (i.e., expected) stimuli are interspersed with rare (i.e., surprising) deviants. Resulting differences in electrophysiological responses following surprising compared to expected stimuli are known as visual mismatch responses (VMRs). VMRs are thought to index co-occurring contributions of stimulus repetition effects, expectation suppression (that occurs when one's expectations are fulfilled), and expectation violation (i.e., surprise) responses; however, these different effects have been conflated in existing oddball designs. To better isolate and quantify effects of expectation suppression and surprise, we adapted an oddball design based on Fast Periodic Visual Stimulation (FPVS) that controls for stimulus repetition effects. We recorded electroencephalography (EEG) while participants (N = 48) viewed stimulation sequences in which a single face identity was periodically presented at 6 Hz. Critically, one of two different face identities (termed oddballs) appeared as every 7th image throughout the sequence. The presentation probabilities of each oddball image within a sequence varied between 10 and 90%, such that participants could form expectations about which oddball face identity was more likely to appear within each sequence. We also included 'expectation neutral' 50% probability sequences, whereby consistently biased expectations would not be formed for either oddball face identity. We found that VMRs indexed surprise responses, and effects of expectation suppression were absent. That is, ERPs were more negative-going at occipitoparietal electrodes for surprising compared to neutral oddballs, but did not differ between expected and neutral oddballs. Surprising oddball-evoked ERPs were also highly similar across the 10-40% appearance probability conditions. Our findings indicate that VMRs which are not accounted for by repetition effects are best described as an all-or-none surprise response, rather than a minimisation of prediction error responses associated with expectation suppression.

Pre-attentive dysfunction of processing emotional faces in interictal migraine revealed by expression-related visual mismatch negativity

BACKGROUND

Several investigations have indicated emotional processing impairment in migraineurs, while no report is available considering the automatic processing of emotional information. In this study, we aimed to characterize the pre-attentive processing of facial expressions in migraine sufferers by recording and analyzing expression-related visual mismatch negativity (EMMN).

METHODS

Altogether, 30 migraineurs (19 females) during the interictal period and 30 age-matched healthy controls (17 females) were recruited. An expression-related oddball paradigm was used to investigate automatic emotional processing, and a group of schematic emotional faces (neutral, happy, sad) unrelated to the participant's task were employed in the experiment in order to avoid low-level processing.

RESULTS

There was no significant difference in behavioral performance (the response accuracy and reaction time) between migraine patients and healthy controls. Nevertheless, the mean EMMN amplitudes within the ranges of 150-250 ms and 250-350 ms were markedly attenuated in patients compared with controls, regardless of happy or sad condition (happy minus neutral or sad minus neutral), and sad EMMN was observed to be larger than happy EMMN only in healthy participants. Moreover, these electrophysiological data directly correlated with frequency and duration of migrainous attacks.

CONCLUSIONS

Our findings implied that the pre-attentive dysfunction of processing both happy and sad expressions was demonstrated in interictal migraineurs, without the existence of negative bias (sad superiority) effect. Further studies on the availability of EMMN as an evaluative marker for migraine are warranted.

Understanding event-related potentials (ERPs) in clinical and basic language and communication disorders research: a tutorial

BACKGROUND

Event-related potentials (ERPs), which are electrophysiological neural responses time-locked to a stimulus, have become an increasingly common tool in language and communication disorders research. They can provide complementary evidence to behavioural measures as well as unique perspectives on communication disorders. ERPs have the distinct advantage of providing precise information about the timing of neural processes and can be used in cases where it is difficult to obtain responses from participants, such as infants or individuals who are minimally verbal. However, clinicians and clinician-scientists rarely receive training in how to interpret ERP research.

AIMS

To provide information that allows readers to better understand, interpret and evaluate research using ERPs. We focus on research related to communication sciences and disorders and the information that is most relevant to interpreting research articles.

METHOD

We explain what ERPs are and how ERP data are collected, referencing key texts and primary research articles. Potential threats to validity, guidelines for interpreting data, and the pros and cons using of ERPs are discussed. Research in the area of paediatric language disorders is used as a model; common paradigms such as the semantic incongruity N400 and auditory mismatch negativity are used as tangible examples. With this foundation of understanding ERPs, the state of the field in terms of how ERPs are used and the ways they may inform the field are discussed.

MAIN CONTRIBUTION

To date, no review has focused on ERPs as they relate to clinical or communication research. The main contribution of this review is that it provides practical information geared toward understanding ERP research.

CONCLUSIONS

ERPs offer insights into neural processes supporting communication and can both complement behaviour and provide information that behavioural measures cannot. We encourage readers to evaluate articles using ERPs critically, effectively pushing the field forward through increased understanding and rigor. What this paper adds ERPs have become more prevalent in research relevant to communication sciences and disorders. In order for clinicians to review and evaluate this research, an understanding of ERPs is needed. This review adds to the field by providing an accessible description of what ERPs are, a description of what ERP components are, and the most relevant commonly used components, as well as how ERP data are recorded and processed. With this foundational understanding of how ERPs work, guidelines for the interpretation of ERP data are given. Though few ERP studies currently have direct implications for clinical practice, we discuss several ways through which ERPs can impact clinical practice in future, by providing information that cannot be obtained by behaviour alone about the aetiology of disorders, and as potential biomarkers of disorder or treatment response.

The effect of hand motion and object orientation on the automatic detection of orientation: A visual mismatch negativity study

We investigated the effects of voluntary hand movements and continuously present objects on the automatic detection of deviant stimuli in a passive oddball paradigm. The visual mismatch negativity (vMMN) component of event-related potentials (ERPs) was measured as the index of automatic deviant detection. The stimuli were textures consisting of parallel, oblique bars with frequent (standard) and infrequent (deviant) orientation. Traditional vMMN was measured by the difference between ERPs to frequent (standard) and infrequent (deviant) textures. Additionally, we measured 'genuine' vMMN by comparing the ERPs to deviant and control textures in the equal probability procedure. Compatible and incompatible hand movement directions to the standard texture had no influence on 'traditional' vMMN and elicited no 'genuine' vMMN. However, the deviant texture elicited 'genuine' vMMN if the orientation of a continuously present rectangle was different from the standard (and identical to the deviant) texture orientation. Our results suggest that the direction of voluntary hand movement and the orientation of task-irrelevant visual patterns do not acquire common memory representation, but a continuously present object contributes to the detection of sequential regularity violation.

Automatic detection advantage of problematic Internet users for Wi-Fi signal cues and the moderating effect of negative affect: An event-related potential study

Cognitive bias toward Internet-related cues is an important factor of the formation and maintenance of the addictive behavior of problematic Internet users (PIUs). The development of fiber-optic communication and smartphones has ushered human society into the era of wireless networks. The Wi-Fi signal, the symbol of wireless network connection, represents not only network access but also a channel for communication with others anywhere at any time. Therefore, the Wi-Fi signal cues should be an effective inducer of the addictive behaviors of PIUs. We used images of Wi-Fi signal as Internet-related cues to explore the automatic detection advantage of PIUs for these cues and to determine whether negative affect, another predisposing factor for addiction, can enhance this advantage. We utilized an intergroup design in this study. The PIU and control groups each comprised 30 participants and were randomly assigned to negative or neutral affect priming group. Mismatch negativity (MMN) was induced through the deviant-standard reverse oddball paradigm. Wi-Fi signal cues and neutral cues were used as standard and deviant stimuli, respectively. Results show that the MMN induced by Wi-Fi signal cues in the PIU group was larger than that in the control group. Meanwhile, the MMN induced by Wi-Fi signal cues was considerably enhanced in the PIU group under negative affect priming relative to that in the PIU group under neutral affect priming. Overall, PIUs have an automatic detection advantage for Wi-Fi signal cues, and negative affect can enhance this advantage. Our results suggest that the MMN elicited by Wi-Fi signal cues function as a sensitive neurobiological marker tracing the change of addiction motivation for PIUs.

Stimulus probability affects the visual N700 component of the event-related potential

OBJECTIVE

To examine whether the occipito-temporal visual N700 component of the event-related potential is sensitive to stimulus probabilities.

METHODS

P1, N1, P3, and, in particular, the occipito-temporal N700 component of the event-related potential were analysed in response to frequent and rare non-target letters of a continuous performance task in 200 healthy adolescents. Additionally, amplitude habituation with time was examined for the occipito-temporal N700 and N1 components.

RESULTS

The visual P1, N1, and occipito-temporal N700 components were significantly larger in response to rare letters than to frequent letters, whereas the P3 component demonstrated no amplitude difference. Over time, the occipito-temporal N700 amplitude decreased in response to the rare letters, while the N1 amplitude increased, to both, frequent and rare letters.

CONCLUSIONS

This study provides first evidence that the visual occipito-temporal N700 is sensitive to stimulus probabilities, suggesting an enhanced post-processing of rare stimuli in secondary visual areas. The distinct habituation patterns of occipito-temporal N700 and N1 amplitudes distinguish repetition effects on stimulus post-processing (N700) from those on perception (N1).

SIGNIFICANCE

The enhanced N700 component to rare stimuli might reflect an orienting response and underlying attentional processes. The N700 sensitivity to stimulus probabilities should be examined in patient groups with attentional deficits.

Prediction errors in surface segmentation are reflected in the visual mismatch negativity, independently of task and surface features

The visual system quickly registers perceptual regularities in the environment and responds to violations in these patterns. Errors of perceptual prediction are associated with electrocortical modulation, including the visual mismatch negativity (vMMN) and P2 event-related potential. One relatively unexplored question is whether these prediction error signals can encode higher-level properties such as surface segmentation, or whether they are limited to lower-level perceptual features. Using a roving standard paradigm, a triangle surface appeared either behind (featuring amodal contours) or in front of (featuring real contours) a second surface with hole-like windows. A surface layout appeared for two to five repetitions before switching to the other "deviant" layout; lighting and orientation of stimuli varied across presentations while remaining isoluminant. Observers responded when they detected a rare "pinched" triangle, which occasionally appeared. Cortical activity-reflected in mismatch responses affecting the P2-N2 and P300 amplitudes-was sensitive to a change in stimulus layout, when surfaces shifted position in depth, following several repetitions. Specifically, layout deviants led to a more negative P2-N2 complex at posterior electrodes, and greater P300 positivity at central sites. Independently of these signals of a deviant surface layout, further modulations of the P2 encoded differences between layouts and detection of the rare target stimulus. Comparison of the effect of preceding layout repetitions on this prediction error signal suggests that it is all or none and not graded with respect to the number of previous repetitions. We show that within the visual domain, unnoticed and task-irrelevant changes in visual surface segmentation leads to observable electrophysiological signals of prediction error that are dissociable from stimulus-specific encoding and lower-level perceptual processing.

Automatic detection advantage of problematic Internet users for Wi-Fi signal cues and the moderating effect of negative affect: An event-related potential study

Cognitive bias toward Internet-related cues is an important factor of the formation and maintenance of the addictive behavior of problematic Internet users (PIUs). The development of fiber-optic communication and smartphones has ushered human society into the era of wireless networks. The Wi-Fi signal, the symbol of wireless network connection, represents not only network access but also a channel for communication with others anywhere at any time. Therefore, the Wi-Fi signal cues should be an effective inducer of the addictive behaviors of PIUs. We used images of Wi-Fi signal as Internet-related cues to explore the automatic detection advantage of PIUs for these cues and to determine whether negative affect, another predisposing factor for addiction, can enhance this advantage. We utilized an intergroup design in this study. The PIU and control groups each comprised 30 participants and were randomly assigned to negative or neutral affect priming group. Mismatch negativity (MMN) was induced through the deviant-standard reverse oddball paradigm. Wi-Fi signal cues and neutral cues were used as standard and deviant stimuli, respectively. Results show that the MMN induced by Wi-Fi signal cues in the PIU group was larger than that in the control group. Meanwhile, the MMN induced by Wi-Fi signal cues was considerably enhanced in the PIU group under negative affect priming relative to that in the PIU group under neutral affect priming. Overall, PIUs have an automatic detection advantage for Wi-Fi signal cues, and negative affect can enhance this advantage. Our results suggest that the MMN elicited by Wi-Fi signal cues function as a sensitive neurobiological marker tracing the change of addiction motivation for PIUs.

Visual mismatch negativity and stimulus-specific adaptation: the role of stimulus complexity

The present study investigated the function of the brain activity underlying the visual mismatch negativity (vMMN) event-related potential (ERP) component. Snowflake patterns (complex stimuli) were presented as deviants and oblique bar patterns (simple stimuli) as standards, and vice versa in a passive oddball paradigm. Control (equiprobable) sequences of either complex shape patterns or oblique bar patterns with various orientations were also presented. VMMN appeared as the difference between the ERP to the oddball deviant and the ERP to the control (deviant minus control ERP difference). Apart from the shorter latency of the vMMN to the oblique bar pattern as deviant, vMMN to both deviants was similar, i.e., there was no amplitude difference. We attributed the function of the brain processes underlying vMMN to the detection of the infrequent stimulus type (also represented in memory) instead of a call for further processing (a possibility for acquiring more precise representation) of the deviant. An unexpected larger adaptation (control minus standard ERP difference) to the snowflake pattern was also obtained. We suggest that this was due to the acquisition of a more elaborate memory representation of the more complex stimulus.

A neuromarker of clinical outcome in attention bias modification therapy for social anxiety disorder

BACKGROUND

Attention bias modification (ABM) therapy aims to modify threat-related attention patterns via computerized tasks. Despite showing medium clinical effect sizes for anxiety disorders, underlying neural-cognitive mechanisms of change remain unclear. We used visual mismatch negativity (vMMN), an event-related potential sensitive to violations of learned statistical contingencies, to assess therapy-related contingency extraction processes in healthy participants and in patients with social anxiety disorder (SAD). We then assessed whether vMMN amplitude predicts ABM treatment outcome.

METHODS

A modified version of the dot-probe task was used to elicit vMMN, in which 80% of trials were standard and 20% were deviant. In study 1, 30 healthy adults were randomly assigned to one of two ABM conditions: one in which threat-congruent targets were deviant trials and threat-incongruent targets were standard trials, and another in which the contingency was reversed. Electroencephalography (EEG) was continuously measured and vMMN analyzed. In study 2, 38 patients with SAD underwent six sessions of ABM therapy. We tested whether rule extraction in the ABM task, indicated by vMMN amplitude, predicts treatment outcome.

RESULTS

vMMN clearly emerged over prespecified scalp locations indicating contingency extraction during ABM (study 1). vMMN amplitude predicted clinical improvement after ABM therapy, uniquely accounting for 7% and 14.4% of the variance in clinician-rated and self-reported posttreatment SAD symptoms, respectively.

CONCLUSIONS

vMMN emerges as a neural marker for contingency learning in ABM, suggesting a significant role for contingency extraction processes in the clinical efficacy of this therapy.

Attention promotes the neural encoding of prediction errors

The encoding of sensory information in the human brain is thought to be optimised by two principal processes: 'prediction' uses stored information to guide the interpretation of forthcoming sensory events, and 'attention' prioritizes these events according to their behavioural relevance. Despite the ubiquitous contributions of attention and prediction to various aspects of perception and cognition, it remains unknown how they interact to modulate information processing in the brain. A recent extension of predictive coding theory suggests that attention optimises the expected precision of predictions by modulating the synaptic gain of prediction error units. Because prediction errors code for the difference between predictions and sensory signals, this model would suggest that attention increases the selectivity for mismatch information in the neural response to a surprising stimulus. Alternative predictive coding models propose that attention increases the activity of prediction (or 'representation') neurons and would therefore suggest that attention and prediction synergistically modulate selectivity for 'feature information' in the brain. Here, we applied forward encoding models to neural activity recorded via electroencephalography (EEG) as human observers performed a simple visual task to test for the effect of attention on both mismatch and feature information in the neural response to surprising stimuli. Participants attended or ignored a periodic stream of gratings, the orientations of which could be either predictable, surprising, or unpredictable. We found that surprising stimuli evoked neural responses that were encoded according to the difference between predicted and observed stimulus features, and that attention facilitated the encoding of this type of information in the brain. These findings advance our understanding of how attention and prediction modulate information processing in the brain, as well as support the theory that attention optimises precision expectations during hierarchical inference by increasing the gain of prediction errors.

Enhancement of a genuine visual mismatch negativity correlates with the facilitation of perceptual alternation of a bistable image

By focusing on the automatic visual change detection process, the present study attempted to clarify neural processing relevant to the exogenously driven perceptual alternation (ePA) of a bistable image. In our recent electroencephalographic study, the oddball paradigm was adopted to the continuous presentation of a bistable image to record visual mismatch negativity (vMMN, a relative enhancement in the brain response to a deviant over a repetitively presented standard, reflecting the visual change detection process and prediction error to the deviant over the standard). In terms of interindividual differences in behavioral and neural data, a correlation was reported previously between the enhancement of vMMN and facilitation of perceptual alternation, suggesting the involvement of the visual change detection process in ePA. However, the vMMN recorded was expected to be confounded by neural adaptation to the repetitively presented standard; thus, it currently remains unclear whether visual change detection not dependent on neural adaptation, reflected in a 'genuine vMMN', is relevant to ePA. To examine this issue, the present study used a new stimulation paradigm, based on the so-called equiprobable paradigm, to mitigate neural adaptation. The results showed that a genuine vMMN significantly emerged and correlated with an increase in the proportion of perceptual alternation across participants. This supports the involvement of the automatic visual change detection process, not dependent on neural adaptation, in facilitating perceptual alternation. The present results provide a deeper understanding of the involvement of the visual change detection process in ePA.

Visual mismatch negativity to disappearing parts of objects and textures

Visual mismatch negativity (vMMN), an event-related signature of automatic detection of events violating sequential regularities is traditionally investigated at the onset of frequent (standard) and rare (deviant) events. In a previous study we obtained vMMN to vanishing parts of continuously presented objects (diamonds with diagonals), and we concluded that the offset-related vMMN is a model of sensitivity to irregular partial occlusion of objects. In the present study we replicated the previous results, but in order to test the object-related interpretation we applied a new condition with a set of separate visual stimuli: a texture of bars with two orientations. In the texture condition (offset of bars with irregular vs. regular orientation) we obtained vMMN, showing that the continuous presence of objects is unnecessary for offset-related vMMN. However, unlike in the object-related condition, reappearance of the previously vanishing lines also elicited vMMN. In principle reappearance of the stimuli is an event with probability 1.0, and according to our results, the object condition reappearance was an expected event. However, the offset and onset of texture elements seems to be treated separately by the system underlying vMMN. As an advantage of the present method, the whole stimulus set during the inter-stimulus interval saturates the visual structures sensitive to stimulus input. Accordingly, the offset-related vMMN is less sensitive to low-level adaptation that differs between the deviant and standard stimuli.

Visual mismatch negativity and representational momentum: Their possible involvement in the same automatic prediction

To maintain real-time interaction with a dynamically changing visual object, the brain is thought to automatically predict the next state of the object based on the pattern of its preceding changes. A behavioral phenomenon known as representational momentum (RM: forward displacement of the remembered final state of an object along its preceding change pattern) and an electrophysiological phenomenon known as visual mismatch negativity (VMMN: an event-related brain potential component that is elicited when an object suddenly deviates from its preceding change pattern) have each indicated the existence of such automatic predictive processes. However, there has been no direct investigation of whether or not these phenomena are involved in the same predictive processes. To address this issue, the present study examined the correlation between RM and VMMN by using a hybrid paradigm in which both phenomena can be measured for the rotation of a bar. The results showed that the magnitudes of RM and VMMN were positively correlated; participants who exhibited greater RM along the regular rotation of a bar tended to show greater VMMN in response to sudden reversal embedded in the regular rotation of a bar. This result provides empirical support for the hypothesis that RM and VMMN may be involved in the same automatic predictive processes. Due to the methodological limitations of a correlation analysis, this hypothesis has to be carefully tested in future studies that examine the relationship between RM and VMMN from multiple perspectives.

Sex and Physiological Cycles Affect the Automatic Perception of Attractive Opposite-Sex Faces: A Visual Mismatch Negativity Study

Facial attractiveness plays important roles in social interaction. Electrophysiological and neuroimaging studies found several brain areas to be differentially responsive to attractive relative to unattractive faces. However, little is known about the time course of the information processing, especially under the unattended condition. Based on a "cross-modal delayed response" paradigm, the present study aimed to explore the automatic mechanism of facial attractiveness processing of females with different physiological cycles and males, respectively, through recording the event-related potentials in response to (un)attractive opposite-sex faces by two experiments. The attractiveness-related visual mismatch negativity (attractiveness vMMN) in posterior scalp distribution was recorded in both the experiments, which indicated that attractive faces could be processed automatically. And high-attractive opposite-sex faces can elicit larger vMMN in males than females in menstrual period in Study 1, but similar as females in ovulatory period in Study 2. Furthermore, by comparison, the latency of attractiveness vMMN in females with the ovulatory period was the longest. These results indicated as follows: (1) Males were more sensitive to attractive female faces, (2) females in ovulatory period were also attracted by the attractive male faces, (3) the long vMMN latency in females during ovulatory period suggested a special reproductive motivation to avoid being tainted by genes, which takes priority over the breeding motivation.