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Zusammenfassung: Die Erfassung der Exekutivfunktionen bei älteren Menschen ist von zentraler Bedeutung, da Defizite in kognitiven Kontroll- und Regulationsprozessen nicht nur einen neurodegenerativen Abbauprozess ankündigen, sondern auch Alltagstätigkeiten beeinträchtigen können. Durch etablierte Screeningverfahren wie Mini-Mental-State-Examination (MMSE) oder Montreal Cognitive Assessment (MoCA) wird dieser heterogene Funktionsbereich jedoch nur eingeschränkt erfasst. In der vorliegenden Arbeit wurde die Klassifikationswahrscheinlichkeit dieser Tests mit dem Screeningverfahren für Exekutivfunktionen (SEF) in einer geriatrischen Stichprobe verglichen. Ähnlich dem MMSE und MoCA, verfügte auch der SEF über eine gute klinische Akzeptanz und Handhabbarkeit. Ein Zusammenhang des neuen Screeningverfahrens zeigte sich mit den exekutiven MoCA-Items. Dabei teilt der SEF nicht die geringe Spezifität des MoCA und ermöglicht daher eine umfassendere Beurteilung exekutiver Funktionen von geriatrischen Patient_innen.

Abstract. Previous studies related subjective cognitive impairment (SCI) in the absence of objectifiable cognitive deficits to a prodromal stage of neurodegenerative diseases. However, there is also evidence that the expression of SCI in older people is primarily determined by the psychoaffective state and is markedly increased in depression. This study provides a better estimation of the impact of a major depression on the SCI level. Our sample comprised 70 participants visiting a memory clinic, 30 whom fulfilled the criteria of a major depressive disorder according to ICD-10 criteria. Using the CPI questionnaire (Complainer Profile Identification), we assessed the level of SCI and its expression in the three cognitive domains of memory, attention, and executive functions. These scores were related in turn to the psychoaffective state (GDS, Geriatric Depression Scale) and the cognitive performance on neuropsychological standard tests. Comparing help-seekers with (HS+) and without (HS−) major depression, we observed that negative mood and SCI level were significantly higher in HS+. Although within a normal performance range, memory and executive functions were also slightly reduced in HS+ compared to HS−. Linear regression analysis revealed that the psychoaffective state predicted the SCI level in HS−, while the cognitive performance did not contribute ( R2: 28.3%). In contrast, both factors significantly contributed to the SCI level in HS+ ( R2: 56.3%). This pattern was also observed for the level of subjective impairment in the memory and executive domain. The results indicate that, when assessing SCI in patients, it is necessary to inquire about the affective state, as patients with a major depression are more likely to suffer from cognitive impairment. Longitudinal research can help to determine whether help-seeking behavior in patients without a depression results from dementia worry or genuinely higher risk of a neurodegenerative disease.

A target that shares features with preceding distractor stimuli is less likely to be detected due to a distractor-driven activation of a negative attentional set. This transient impairment in perceiving the target (distractor-induced blindness/deafness) can be found within vision and audition. Recently, the phenomenon was observed in a cross-modal setting involving an auditory target and additional task-relevant visual information (cross-modal distractor-induced deafness). In the current study, consisting of three behavioral experiments, a visual target, indicated by an auditory cue, had to be detected despite the presence of visual distractors. Multiple distractors consistently led to reduced target detection if cue and target appeared in close temporal proximity, confirming cross-modal distractor-induced blindness. However, the effect on target detection was reduced compared to the effect of cross-modal distractor-induced deafness previously observed for reversed modalities. The physical features defining cue and target could not account for the diminished distractor effect in the current cross-modal task. Instead, this finding may be attributed to the auditory cue acting as an especially efficient release signal of the distractor-induced inhibition. Additionally, a multisensory enhancement of visual target detection by the concurrent auditory signal might have contributed to the reduced distractor effect.

Deficits in spatial navigation in three-dimensional space are prevalent in various neurological disorders and are a sensitive cognitive marker for prodromal Alzheimer’s disease, but are also associated with non-pathological aging. However, standard neuropsychological tests used in clinical settings lack ecological validity to adequately assess spatial navigation. Experimental paradigms, on the other hand, are often too difficult for seniors or patients with cognitive or motor impairments since most require operating a human interface device (HID) or use complex episodic memory tasks. Here, we introduce an intuitive navigation assessment, which is conceptualized using cognitive models of spatial navigation and designed to account for the limited technical experience and diverging impairments of elderly participants and neurological patients. The brief computer paradigm uses videos of hallways filmed with eye tracking glasses, without employing an episodic memory task or requiring participants to operate a HID. Proof of concept data from 34 healthy, middle-aged and elderly participants (56 - 78 years) provide evidence for the assessment’s feasibility and construct validity as a navigation paradigm. Test performance showed normal distribution and was sensitive to age and education, which needs to be considered when investigating the assessment’s psychometric properties in larger samples and clinical populations. Correlations of the navigation assessment with other neuropsychological tests confirmed its dependence on visuospatial skills rather than visual episodic memory, with age driving the association with working memory. The novel paradigm is suitable for a differentiated investigation of spatial navigation in elderly individuals and promising for experimental research in clinical settings.

The aim of the present study was to test the classic but under-researched hypothesis that individual differences in automatic emotional mimicry are positively related to individual differences in emotional contagion. To tap automatic mimicry and automatic emotional contagion, participants were exposed to affective stimuli with either a positive or negative valence (faces with a happy expression, n = 73; faces with a sad expression, n = 73) while their attention was directed toward nonaffective features of the stimuli. Emotional mimicry was measured with EMG (Corrugator, Zygomaticus). On average, in the sad emotional expression condition, participants’ mood worsened, but the happy emotional expression condition did not evoke a general positive emotional contagion effect (across participants). Multigroup multilevel latent difference models revealed that in the sad emotional expression condition, individual differences in Corrugator activity were related to a larger increase in unpleasant mood, and in the happy emotional expression condition, individual differences in Zygomaticus activity were related to a larger decrease in unpleasant mood. That is, results of this study provided support for the mimicry-contagion link.

We investigated how patients with social anxiety disorder (SAD) and patients with borderline personality disorder (BPD) process an increase in the frequency of social interaction. We used an EEG-compatible version of the online ball-tossing game Cyberball to induce an increase in the frequency of social interaction. In the first condition, each player received the ball equally often (inclusion: 33% ball reception). In the following condition, the frequency of the ball reception was increased (overinclusion: 45% ball reception). The main outcome variable was the event-related potential P2, an indicator for social reward processing. Moreover, positive emotions were assessed. Twenty-eight patients with SAD, 29 patients with BPD and 28 healthy controls (HCs) participated. As expected, HCs and patients with BPD, but not patients with SAD, showed an increase in the P2 amplitude from the inclusion to the overinclusion condition. Contrary to our expectations, positive emotions did not change from the inclusion to the overinclusion condition. EEG results provide preliminary evidence that patients with BPD and HCs, but not patients with SAD, process an increase in the frequency of social interaction as rewarding.

Integrating information across different senses is a central feature of human perception. Previous research suggests that multisensory integration is shaped by a context-dependent and largely adaptive interplay between stimulus-driven bottom-up and top-down endogenous influences. One critical question concerns the extent to which this interplay is sensitive to the amount of available cognitive resources. In the present study, we investigated the influence of limited cognitive resources on audiovisual integration by measuring high-density electroencephalography (EEG) in healthy participants performing the sound-induced flash illusion (SIFI) and a verbaln-back task (0-back, low load and 2-back, high load) in a dual-task design. In the SIFI, the integration of a flash with two rapid beeps can induce the illusory perception of two flashes. We found that high compared with low load increased illusion susceptibility and modulated neural oscillations underlying illusion-related crossmodal interactions. Illusion perception under high load was associated with reduced early β power (18–26 Hz, ∼70 ms) in auditory and motor areas, presumably reflecting an early mismatch signal and subsequent top-down influences including increased frontal θ power (7–9 Hz, ∼120 ms) in mid-anterior cingulate cortex (ACC) and a later β power suppression (13–22 Hz, ∼350 ms) in prefrontal and auditory cortex. Our study demonstrates that integrative crossmodal interactions underlying the SIFI are sensitive to the amount of available cognitive resources and that multisensory integration engages top-down θ and β oscillations when cognitive resources are scarce.SIGNIFICANCE STATEMENTThe integration of information across multiple senses, a remarkable ability of our perceptual system, is influenced by multiple context-related factors, the role of which is highly debated. It is, for instance, poorly understood how available cognitive resources influence crossmodal interactions during multisensory integration. We addressed this question using the sound-induced flash illusion (SIFI), a phenomenon in which the integration of two rapid beeps together with a flash induces the illusion of a second flash. Replicating our previous work, we demonstrate that depletion of cognitive resources through a working memory (WM) task increases the perception of the illusion. With respect to the underlying neural processes, we show that when available resources are limited, multisensory integration engages top-down θ and β oscillations.

Current predictive processing accounts consider negative affect to result from elevated rates of prediction error, thereby motivating changes in the degree with which prior expectancies and sensory evidence influence our perceptions. Trait anxiety is associated with the amount of negative affect a person is experiencing and has been linked to aberrant strategies in decision making and belief updating. Here, we assessed the degree to which induced prior expectancies influenced motion judgements in a simple perceptual decision making task in 117 healthy participants with varying levels of trait anxiety. High trait anxious individuals showed increased usage of priors, independent from the amount of sensory uncertainty that was perceived. This finding demonstrates aberrant strategies of belief updating in anxiety even in evaluating nonthreatening visual motion stimuli, and thus suggest an influential role of affective traits in processes of perceptual inference.

Conscious access to a target stimulus embedded in a rapid serial visual presentation can be impaired by the preceding presentation of multiple task-irrelevant distractors. While this phenomenon – labeled distractor-induced blindness (DIB) – is established in vision, it is unknown whether a similar effect can be observed in the auditory modality. Considering the differences in the processing of visual and auditory stimuli, modality-specific effects in the inhibitory mechanisms triggered by distractors can be expected. First, we aimed to find evidence for a distractor-induced deafness (DID) for auditory targets in a behavioral experiment. The target was defined by a transient increase in amplitude in a continuous sinusoidal tone, which was to be detected if accompanied or preceded by a deviant tone (cue). Both events were embedded in separate streams in a binaural rapid serial auditory presentation. Distractors preceded the cue and shared the target's features. As previously observed for DIB, a failure to detect the auditory target critically relied on the presentation of multiple distractor episodes. This DID effect was followed up in a subsequent event-related brain potentials (ERP) study to identify the signature of target detection. In contrast to missed targets, hits were characterized by a larger frontal negativity and by a more pronounced centro-parietal P3b wave. Whereas the latter process was also observed in the visual domain, indicating a post-perceptual updating process, the frontal negativity was exclusively observed for auditory DID. This modality-specific process might signal that early attentional control processes support conscious access to relevant auditory events.

The selection of relevant stimuli is partially achieved through inhibition of irrelevant distractors. Using the distractor induced blindness (DIB) paradigm, we investigated whether these inhibitory processes depend on the feature dimension that is used to define distractors. Following a pilot study that found motion and colour targets to be comparably salient, we analysed distractor effects of those two feature dimensions. In both feature dimensions, an inhibition effect depended on the number of distractors. Colour, however, was more sensitive to distractor episodes as compared to motion: The level of inhibition was more pronounced, and its activation required less distractors. The results of a control experiment provided further evidence that, in fact, the feature dimension -instead of design differences between tasks- is responsible for this observation. The dimension-sensitive bias in the activation of a central inhibition system may be attributed to a differential processing of visual signals...

Previous research showed that dual-task processes such as the attentional blink are not always transferable from unimodal to cross-modal settings. This study investigated whether such a transfer can be stated for a distractor-induced impairment of target detection established in vision (distractor-induced blindness, DIB) and recently observed in the auditory modality (distractor-induced deafness, DID). A cross-modal DID effect was confirmed: The detection of an auditory target indicated by a visual cue was impaired if multiple auditory distractors preceded the target. Event-related potentials (ERPs) were used to identify psychophysiological correlates of target detection. A frontal negativity about 200 ms succeeded by a sustained, widespread negativity was associated with auditory target awareness. In contrast to unimodal findings, P3 amplitude was not enhanced for hits. The results support the notion that early frontal attentional processes are linked to auditory awareness, whereas the P3 does not seem to be a reliable indicator of target access.

In a rapid serial visual presentation task, inhibition processes cumulatively impair processing of a target possessing distractor properties. This phenomenon-known as distractor-induced blindness-has thus far only been elicited using dynamic visual features, such as motion and orientation changes. In three ERP experiments, we used a visual object feature-color-to test for the adaptability and specificity of the effect. In Experiment I, participants responded to a color change (target) in the periphery whose onset was signaled by a central cue. Presentation of irrelevant color changes prior to the cue (distractors) led to reduced target detection, accompanied by a frontal ERP negativity that increased with increasing number of distractors, similar to the effects previously found for dynamic targets. This suggests that distractor-induced blindness is adaptable to color features. In Experiment II, the target consisted of coherent motion contrasting the color distractors. Correlates of distractor-induced blindness were found neither in the behavioral nor in the ERP data, indicating a feature specificity of the process. Experiment III confirmed the strict distinction between congruent and incongruent distractors: A single color distractor was embedded in a stream of motion distractors with the target consisting of a coherent motion. While behavioral performance was affected by the distractors, the color distractor did not elicit a frontal negativity. The experiments show that distractor-induced blindness is also triggered by visual stimuli predominantly processed in the ventral stream. The strict specificity of the central inhibition process also applies to these stimulus features.

The clinical use of subjective cognitive complaints (SCCs) has been questioned, especially when considering the influence of depression. Further problems describe the registration of SCCs with a focus on memory and different sample selections, with only few studies that directly compare those who seek help because of SCCs and community-dwelling adults. The present study aimed to (1) evaluate differences in psychosocial variables in help-seeking adults and community-dwelling adults with a lower level of complaints and (2) to further explore the relationship between SCCs and cognitive performance in help-seekers. Fifty-five help-seeking adults (HS) were compared to 55 age-, sex-, and education-matched non-help-seeking adults (NHS). Multiple regression analyses revealed that depressive symptoms were linked to experiencing more SCCs mainly in NHS. Altogether, less variance was explained by psychosocial variables in HS, whereas adding cognitive variables—especially divided attention performance—led to a substantial increase in explained variance. Mediation analysis further revealed a possible mediation of depressive symptoms on SCC by divided attention performance. Taken together, our results underpin the importance of assessing SCCs comprehensively to detect a functional relationship between cognitive performance and complaints, especially in HS. In this group, it is likely that depression precedes problems in divided attention, which in turn lead to SCC. Therefore, future studies should further investigate the link between SCC and cognitive functions which rely on more cognitive resources, as these might be first to be affected by cognitive decline.

In order to study the changing relevance of stimulus features in time and space, we used a task with rapid serial presentation of two stimulus streams where two targets (&ldquo, T1&rdquo, and &ldquo, T2&rdquo, ) had to be distinguished from background stimuli and where the difficult T2 distinction was impeded by background stimuli presented before T1 that resemble T2 (&ldquo, lures&rdquo, ). Such lures might actually have dual characteristics: Their capturing attention might interfere with target identification, whereas their similarity to T2 might result in positive priming. To test this idea here, T2 was a blue digit among black letters, and lures resembled T2 either by alphanumeric category (black digits) or by salience (blue letters). Same-category lures were expected to prime T2 identification whereas salient lures would impede T2 identification. Results confirmed these predictions, yet the precise pattern of results did not fit our conceptual framework. To account for this pattern, we speculate that lures serve to confuse participants about the order of events, and the major factor distinguishing color lures and digit lures is their confusability with T2. Mechanisms of effects were additionally explored by measuring event-related EEG potentials. Consistent with the assumption that they attract more attention, color lures evoked larger N2pc than digit lures and affected the ensuing T1-evoked N2pc. T2-evoked N2pc was indistinguishably reduced by all kinds of preceding lures, though. Lure-evoked mesio-frontal negativity increased from first to third lures both with digit and color lures and, thereby, might have reflected expectancy for T1.

Background: Mirror therapy (MT) was found to improve motor function after stroke. However, there is high variability between patients regarding motor recovery. Objectives: The following pilot study was designed to identify potential factors determining this variability between patients with severe upper limb paresis, receiving MT. Methods: Eleven sub-acute stroke patients with severe upper limb paresis participated, receiving in-patient rehabilitation. After a set of pre-assessments (including measurement of brain activity at the primary motor cortex and precuneus during the mirror illusion, using near-infrared spectroscopy as described previously), four weeks of MT were applied, followed by a set of post-assessments. Discriminant group analysis for MT responders and non-responders was performed. Results: Six out of eleven patients were defined as responders and five as non-responders on the basis of their functional motor improvement. The initial motor function and the activity shift in both precunei (mirror index) were found to discriminate significantly between responders and non-responders. Conclusions: In line with earlier results, initial motor function was confirmed as crucial determinant of motor recovery. Additionally, activity response to the mirror illusion in both precunei was found to be a candidate for determination of the efficacy of MT.

In this study we investigated age-related changes in WM capacity and their respective ERP correlates. We explicitly addressed the differentiation between high and low performing elderly to identify electrophysiological correlates of successful aging. Therefore, ERP and behavioral data was obtained from 45 young (mean = 22.73 years) and 35 older participants (mean = 68.49 years). Both groups performed a visual-spatial n-back task with two levels of difficulty. Additionally, related neuropsychological tests were administered. Older subjects performed less accurately in both conditions of the n-back task. Older age was additionally associated with a reduced fronto-central positivity (labeled as P200) in the 2-back task and an overall reduced amplitude of the parietal positivity (labeled as P300). The latter shifted to frontal leads in older subjects. Additionally, only in the group of the older participants, increased P200 and decreased parietal P300 amplitudes correlated with performance. Regarding older high and low performers, we observed a clear shift of frontal activity of both ERP components in the group of high performers. High performers additionally performed better in spatial working memory, verbal learning, and fluid intelligence tasks. We conclude, that increasing demands of working memory load are accompanied by a reallocation of resources in both young and older adults. With age, executive control and updating processes (indexed by both ERP components) are diminished or rely on more frontal processes for compensation. However, high performing older adults, who perform comparable to young adults, sustain comparable executive control processes, exceeding pure compensation.

Background: In rare cases, patients with Alzheimer disease (AD) present at an early age and with a family history suggestive of an autosomal dominant mode of inheritance. Mutations of the presenilin-1 (PSEN1) gene are the most common causes of dementia in these patients. Early-onset and particularly familial AD patients frequently present with variable non-amnestic cognitive symptoms such as visual, language or behavioural changes as well as non-cognitive, e.g. motor, symptoms. Objective: To investigate the phenotypic variability in carriers of the PSEN1 S170F mutation. Methods: We report a family with 4 patients carrying the S170F mutation of whom 2 underwent detailed clinical examinations. We discuss our current findings in the context of previously reported S170F cases. Results: The clinical phenotype was consistent regarding initial memory impairment and early onset in the late twenties found in all S170F patients. There were frequent non-amnestic cognitive changes and, at early stages of the disease, indications of a more pronounced disturbance of visuospatial abilities as compared to face and object recognition. Non-cognitive symptoms most often included myoclonus and cerebellar ataxia. A review of the available case reports indicates some phenotypic variability associated with the S170F mutation including different constellations of symptoms such as parkinsonism and delusions. Conclusion: The variable clinical findings associated with the S170F mutation highlight the relevance of atypical phenotypes in the context of research and under a clinical perspective. CSF sampling and detection of Aβ species may be essential to indicate AD pathology in unclear cases presenting with cognitive and motor symptoms at a younger age.

Recent behavioral and neuroimaging studies have suggested multisensory processing deficits in patients with schizophrenia (SCZ). Thus far, the neural mechanisms underlying these deficits are not well understood. Previous studies with unisensory stimulation have shown altered neural oscillations in SCZ. As such, altered oscillations could contribute to aberrant multisensory processing in this patient group. To test this assumption, we conducted an electroencephalography (EEG) study in 15 SCZ and 15 control participants in whom we examined neural oscillations and event-related potentials (ERPs) in the sound-induced flash illusion (SIFI). In the SIFI multiple auditory stimuli that are presented alongside a single visual stimulus can induce the illusory percept of multiple visual stimuli. In SCZ and control participants we compared ERPs and neural oscillations between trials that induced an illusion and trials that did not induce an illusion. On the behavioral level, SCZ (55.7%) and control participants (55.4%) did not significantly differ in illusion rates. The analysis of ERPs revealed diminished amplitudes and altered multisensory processing in SCZ compared to controls around 135 ms after stimulus onset. Moreover, the analysis of neural oscillations revealed altered 25–35 Hz power after 100 to 150 ms over occipital scalp for SCZ compared to controls. Our findings extend previous observations of aberrant neural oscillations in unisensory perception paradigms. They suggest that altered ERPs and altered occipital beta/gamma band power reflect aberrant multisensory processing in SCZ.

Subjective cognitive complaints (SCC) and their role as a possible indicator for subsequent dementia became of growing interest in recent research. In contrast to studies that focused primarily on memory complaints, we aimed to (a) evaluate a questionnaire to register SCC in multiple cognitive domains (Complainer Profile Identification, CPI), (b) assess the association between SCC and psychosocial variables, and (c) assess whether complainer types can be differentiated. Confirmatory factor analysis to evaluate construct validity was computed based on a sample of 734 healthy participants (mean [M] = 43.15 years). On a subsample of 644 participants, the relationship between the total level of SCC with age, depression, social integration, and aging stereotypes was assessed utilizing multiple regression analysis. Differences in complainer types were assessed by multivariate analysis of variance. The results indicate sound psychometric properties of the CPI. The overall level of SCC is largely influenced by depressiveness, whereas executive complainers show the highest level of depressive affect, being overall younger and less socially integrated.

Previous research suggests that the established link of vertical position and self-assignment of social power affects the processing of social exclusion. We hypothesized that verticality-induced self-assignment of social power moderates the evaluation of exclusion via a change in subjective expectancy of social participation. Following this idea, a superior position-associated with higher power-was supposed to increase the sensitivity for a transition to social exclusion. The transition was simulated in a virtual ball tossing game (cyberball): an inclusionary block was followed by partial exclusion of the participant. The participants' vertical position relative to the co-players was varied in three experimental groups (superior vs. even vs. inferior). From inclusion to partial exclusion, we observed an increase of an event-related brain potential related to the violation of subjective expectancy (P3), and participants reported a corresponding increase in threat to social needs and negative mood. For participants at inferior position exclusionary effects on both, P3 and need threat, were less pronounced as compared to participants at even or superior position. These results indicate that verticality impacts basic cognitive processes of subjective expectancy formation. An inferior position already provides a bias for the loss of social power, and the transition to social exclusion is less unexpected.

The detection of a salient visual target embedded in a rapid serial visual presentation (RSVP) can be severely affected if target-like distractors are presented previously. This phenomenon, known as distractor-induced blindness (DIB), shares the prerequisites of contingent attentional capture (Folk, Remington, & Johnston, 1992). In both, target processing is transiently impaired by the presentation of distractors defined by similar features. In the present study, we investigated whether the speeded response to a target in the DIB paradigm can be described in terms of a contingent attentional capture process. In the first experiments, multiple distractors were embedded in the RSVP stream. Distractors either shared the target's visual features (Experiment 1A) or differed from them (Experiment 1B). Congruent with hypotheses drawn from contingent attentional capture theory, response times (RTs) were exclusively impaired in conditions with target-like distractors. However, RTs were not impaired if only one single target-like distractor was presented (Experiment 2). If attentional capture directly contributed to DIB, the single distractor should be sufficient to impair target processing. In conclusion, DIB is not due to contingent attentional capture, but may rely on a central suppression process triggered by multiple distractors.

The formation of coherent multisensory percepts requires integration of stimuli across the multiple senses. Patients with schizophrenia (ScZ) often experience a loss of coherent perception and hence, they might also show dysfunctional multisensory processing. In this high-density electroencephalography study, we investigated the neural signatures of the McGurk illusion, as a phenomenon of speech-specific multisensory processing. In the McGurk illusion lip movements are paired with incongruent auditory syllables, which can induce a fused percept. In ScZ patients and healthy controls we compared neural oscillations and event-related potentials (ERPs) to congruent audiovisual speech stimuli and McGurk illusion trials, where a visual /ga/ and an auditory /pa/ was often perceived as /ka/. There were no significant group differences in illusion rates. The EEG data analysis revealed larger short latency ERPs to McGurk illusion compared with congruent trials in controls. The reversed effect pattern was found in ScZ patients, indicating an early audiovisual processing deficit. Moreover, we observed stronger suppression of medio-central alpha-band power (8–10 Hz, 550–700 ms) in response to McGurk illusion compared with control trials in the control group. Again, the reversed pattern was found in SCZ patients. Moreover, within groups, alpha-band suppression was negatively correlated with the McGurk illusion rate in ScZ patients, while the correlation tended to be positive in controls. The topography of alpha-band effects indicated an involvement of auditory and/or frontal structures. Our study suggests that short latency ERPs and long latency alpha-band oscillations reflect abnormal multisensory processing of the McGurk illusion in ScZ.

In many rapid serial presentation tasks, two targets ("T1" and "T2") have to be distinguished from background stimuli. Here, digits ("lures") were interspersed among the background letters, differing from the T2 digit by occurring before rather than after T1. The resulting inhibitory effects on T2 identification may either be evoked directly by the lures or be triggered by T1, interfering with positive priming of lures on T2. To distinguish between these two alternatives, lures, T1, and T2 were presented in two different simultaneously running streams, T2 was or was not the same digit as a lure, and EEG potentials related to lures, T1, and T2 were recorded. Effects on T2 identification better fit the view that lures exerted positive priming interrupted by T1. Recurrence of lures in the trial led to abridged duration of the lure-evoked N2pc, and T2-evoked N2pc was reduced after lures. Also these N2pc effects may reflect positive priming.

The inhibitory effect of the processing of target-like distracters has already been shown to affect the conscious detection of simple motion and simple orientation stimuli in a random dot kinematogram. In two experiments we examined the effects of single-feature motion distracters, single-feature orientation distracters, and combined-feature distracters containing both motion and orientation information. The target was specified as a coherent motion episode (Experiment 1) or as a combined-feature episode where the coherent motion was accompanied by an abrupt change in line orientation (Experiment 2). Results showed that (a) the respective feature-specific inhibitory processes operate separately even when the distracter features are presented simultaneously and (b) both inhibitory processes contribute to the blindness effect when the conjunction of two features is defined as the target. Again, this inhibitory-process is feature-specific: Only features that are defined in the task are represented in the inhibitory task set. In case of combined- feature task-sets, these representations remain separate, so that combined-feature distracters as well as single-feature distracters are able to induce blindness effects.

Although a moderate blood alcohol concentration already affects attention, an effect on early visual processing is still questionable. Using psychophysical measures and visually evoked potentials (VEP), we examined the effects of alcohol on the processing of contrast and motion features. In our tasks, two lateralized stimuli were briefly presented, and participants had to identify either the stimulus of higher contrast or motion coherence. In the contrast task, alcohol was found to decrease the discrimination ability and induced a global attenuation of VEP amplitudes. In the motion task, discrimination was not impaired. VEP amplitudes were reduced contralateral to the target position, indicating an effect of alcohol on the deployment of visuospatial attention. In sum, our data suggest that specialized areas for motion and contrast processing within the visual cortex are differently sensitive to moderate alcohol exposure.

The conscious perception of simple visual stimuli can be modulated by the presence of distractors. In the motion blindness paradigm, the detection of coherent motion is impaired when task-irrelevant motion distractors are presented prior to the target. Aim of this study was to examine the feature specificity of the distractor effect. For this reason, targets were either defined by motion coherence (“motion blindness”) or orientation changes (“orientation blindness”). In a series of three experiments we show that distractors have to share the feature characteristics of the target in order to reduce its detectability. However, independent inhibition sets for visual features can be activated if the targets’ characteristics are ambiguous.

We examined the electrophysiological correlates of the processing of social exclusion and inclusion by using a modified version of the Cyberball paradigm. Exclusion was found to be associated with a significant increase in the P3 complex. The frontal-central P3a was primarily related to the affective processing of rejection, whereas the late parietal P3b was associated with its perceived intensity. The expression of P3a and negative mood did also depend on the earlier experience; earlier inclusion affected the processing of exclusion, and vice versa. In conclusion, our data indicate that the complex process of social rejection can be tracked by using event-related brain potentials.

An experiment is reported in which the cue mismatch hypothesis of negative priming, an important novel variant of the mismatching hypothesis, was tested. A cue mismatch and a no mismatch condition were contrasted in a visual discrimination task. In the prime display of cue mismatch ignored-repetition trials, the colour of the prime distractor was different from the colour of the cue indicating the selection feature (coloured square). In probe displays, cue and repeated stimulus had the same colour. In the no mismatch condition, the visual cue was neutral in terms of colour (always black), so that there was always no cue mismatch between prime and probe displays. Contrary to the prediction of the cue mismatch hypothesis, the negative priming effect was not larger in the cue mismatch than in the no mismatch condition. The cue mismatch hypothesis must therefore be rejected. In contrast, the episodic retrieval account is consistent with the results.

Patients with borderline personality disorder (BPD) and patients with social anxiety disorder (SAD) are known to be highly sensitive to social rejection. Social information processing is assumed to play a key role for this shared psychopathological phenomenon. The first steps in social information processing are to encode social cues and to create a mental representation of the social situation. The aim of the current study was to test whether the perception of social participation in patients with BPD and patients with SAD is biased in this initial stage of social processing. Focus was on the P3b, a brain potential related to stimulus evaluation that has been shown to be a sensitive indicator for the processes of interest. Twenty five unmedicated patients with BPD, 25 unmedicated patients with SAD and 25 healthy controls (HC) played an EEG-compatible version of Cyberball, a virtual ball-tossing paradigm that experimentally induces social inclusion and exclusion. All participants showed a pronounced P3b when excluded. Only patients with BPD showed an enhanced P3b also during the inclusion condition, indicating altered processing of social inclusion. The EEG results for the BPD group were consistent with their self-report data. Patients with BPD felt more excluded during the inclusion condition of Cyberball than both HC and patients with SAD. Furthermore, heightened rejection expectancy (subscale of the Rejection Sensitivity Questionnaire) was associated with a smaller difference in the P3b amplitude between inclusion and exclusion. Results indicate a negatively biased perception of social inclusion in BPD already during the initial stage of social processing.

A virtual ball-tossing game called Cyberball has allowed the identification of neural structures involved in the processing of social exclusion by using neurocognitive methods. However, there is still an ongoing debate if structures involved are either pain- or exclusion-specific or part of a broader network. In electrophysiological Cyberball studies we have shown that the P3b component is sensitive to exclusion manipulations, possibly modulated by the probability of ball possession of the participant (event “self”) or the presumed co-players (event “other”). Since it is known from oddball studies that the P3b is not only modulated by the objective probability of an event, but also by subjective expectancy, we independently manipulated the probability of the events “self” and “other” and the expectancy for these events. Questionnaire data indicate that social need threat is only induced when the expectancy for involvement in the ball-tossing game is violated. Similarly, the P3b amplitude of both “self” and “other” events was a correlate of expectancy violation. We conclude that both the subjective report of exclusion and the P3b effect induced in the Cyberball paradigm are primarily based on a cognitive process sensitive to expectancy violations, and that the P3b is not related to the activation of an exclusion-specific neural alarm system.

In contrast to the visual spatial domain, the effect of attention on sensory processing and stimulus appearance in temporal selection tasks is still controversial. Using a rapid serial visual presentation (RSVP) procedure, we examined whether the stimulus onset asynchrony (SOA) between a color cue and a motion target affects the appearance of the latter. Event-related brain potentials (ERPs) recorded simultaneously allowed us to test whether a change in the targets' appearance is associated with a modulation of the sensory ERP components. In the experimental condition 'SOA', the temporal interval between the cue and the target was varied between 0 and 300 ms. In a control condition, the physical appearance of the motion target was varied (level of coherence: 25-100%) while holding the cue-target SOA constant (300 ms). In trials when the participant detected the target motion, his/her task was to report the strength of the perceived motion on a 5-point scale. In both conditions, the mean rating of the target's appearance increased monotonically with increasing SOA and the level of coherence, respectively. The psychophysical ratings were associated with an increase of a negative deflection about 200 ms (N200) related to the sensory processing of visual motion. The physical variation of motion coherence and the variation of the cue-target SOA affected the N200 response in similar fashion. These results indicate that sensory processing is also modulated by attentional resources in temporal selection tasks which - in turn - affect the appearance of the relevant target stimulus.

There is growing evidence that motion perception is modulated by visual selective attention. In the ‘attention-induced motion blindness’ paradigm the detection of coherent motion in a random dot kinematogram (RDK) is impaired in a rapid serial presentation task [Sahraie, A., Milders, M., & Niedeggen, M. (2001). Attention induced motion blindness. Vision Research, 41, 1613–1617]. The effect depends on irrelevant motion episodes (distractors) prior to the target. In this study, we show that both the number and timing of distractors affect detection performance, allowing for implications on the build-up and release of inhibition. Furthermore, we rule out the possibility that subjects falsely classify targets as distractors due to uncertainty of temporal order.

Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of "cognitive" and "perceptual" load.

Responding to a stimulus that had to be ignored previously is usually slowed-down (negative priming effect). This study investigates the reaction time and ERP effects of the negative priming phenomenon in the auditory domain. Thirty participants had to categorize sounds as musical instruments or animal voices. Reaction times were slowed-down in the negative priming condition relative to two control conditions. This effect was stronger for slow reactions (above intraindividual median) than for fast reactions (below intraindividual median). ERP analysis revealed a parietally located negativity of the negative priming condition compared to the control conditions between 550-730 ms poststimulus. This replicates the findings of Mayr, Niedeggen, Buchner, and Pietrowsky (2003) . The ERP correlate was more pronounced for slow trials (above intraindividual median) than for fast trials (below intraindividual median). The dependency of the negative priming effect size on the reaction time level found in the reaction time analysis as well as in the ERP analysis is consistent with both the inhibition as well as the episodic retrieval account of negative priming. A methodological artifact explanation of this effect-size dependency is discussed and discarded.

Neurobiological studies of visual awareness usually focus on the neural events elicited by perceived or nonperceived stimuli but neglect the preexisting conditions that allow (or prevent) conscious perception. We have examined the conditions that lead to temporary motion blindness in a rapid serial visual presentation paradigm, in which subjects have to detect coherent motion in the peripheral stream after a cue (a red fixation point) in the central stream. The failure of awareness depends critically on the occurrence of similar coherent motion events (probes) before the cue. Event-related brain potentials (ERPs) were recorded to track the processing of motion distractors, which determine the prerequisites for this transient deficit. Analysis of motion-evoked responses revealed that there is no progressive reduction in sensitivity in early visual processing. There is, however, a progressive increase in amplitude of a negative wave over the frontal cortex at approximately 250 msec after motion onset and a corresponding reduction of a centro-parietal positivity at approximately 350 msec with an increasing number of distractors. We propose that these nonsensory ERP components reflect a postperceptual frontal gating mechanism that controls the access of visual stimuli to higher order evaluation and conscious detection.

Repetition blindness (RB) was used to investigate whether illusory words emerge at a lexical-perceptual or a semantic-reconstructional level. Illusory words were evoked by the rapid serial visual presentation (RSVP) of two real words and a word fragment. The initial words share the same string of letters (“CREEP”–“SHEEP”), producing a free-floating word fragment (“SH”). This fragment is likely to be linked to a subsequently presented fragment (“IFT”) if both combine to a meaningful word (“SHIFT”). The processing level of the illusions was probed by prime words preceding the RSVP sequence which were semantically related or unrelated to the second real word or to the illusion. Behavioural and electrophysiological correlates of the semantic priming effect were recorded in 14 subjects. Real words related to the prime were perceived more frequently, and evoked widespread N400-like effect in the event-related brain potentials (ERPs). An ERP effect of the same polarity was obtained for illusory words, however, its latency was delayed and the topographical distribution was restricted to left posterior electrode positions. These differences suggest that priming might affect real and illusory words at different levels of word processing: access to real words is facilitated at a semantic level, whereas lexical activation apparently accompanies the generation of illusory words.