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Visual stimuli that are made invisible by a following mask can affect overt motor responses and nonmotor processing. Previous studies have compared the effects of primes that were perceptually similar to the subsequent stimulus with those of primes that were perceptually similar to an alternative stimulus. The present study examined the effect of congruent primes that are perceptually dissimilar to the target (or the cue) but are nonetheless associated with the same response (or the same task) as the later stimulus. Positive and inverse priming effects (negative compatibility effects) were studied in a target priming paradigm (Experiments 1 and 2) and in a cue priming paradigm (Experiments 3 and 4). The results showed stronger priming effects with similar primes than with dissimilar congruent primes. However, the effects of perceptually dissimilar congruent primes differed from those of dissimilar incongruent primes. These findings suggest that a substantial part of both positive target and cue priming effects is produced at levels of processing that are not affected by perceptual similarity. The version of inverse priming effects examined in this study, however, seems to arise from perceptual processing that is affected by the similarity between a prime and the stimulus that follows the mask. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Psychological and neuroscience approaches have promoted much progress in elucidating the cognitive and neural mechanisms that underlie phenomenal visual awareness during the last decades. In this article, we provide an overview of the latest research investigating important phenomena in conscious and unconscious vision. We identify general principles to characterize conscious and unconscious visual perception, which may serve as important building blocks for a unified model to explain the plethora of findings. We argue that in particular the integration of principles from both conscious and unconscious vision is advantageous and provides critical constraints for developing adequate theoretical models. Based on the principles identified in our review, we outline essential components of a unified model of conscious and unconscious visual perception. We propose that awareness refers to consolidated visual representations, which are accessible to the entire brain and therefore globally available. However, visual awareness not only depends on consolidation within the visual system, but is additionally the result of a post-sensory gating process, which is mediated by higher-level cognitive control mechanisms. We further propose that amplification of visual representations by attentional sensitization is not exclusive to the domain of conscious perception, but also applies to visual stimuli, which remain unconscious. Conscious and unconscious processing modes are highly interdependent with influences in both directions. We therefore argue that exactly this interdependence renders a unified model of conscious and unconscious visual perception valuable. Computational modeling jointly with focused experimental research could lead to a better understanding of the plethora of empirical phenomena in consciousness research. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

The inverse priming paradigm can be considered one example which demonstrates the operation of control processes in the absence of conscious experience of the inducing stimuli. Inverse priming is generated by a prime that is followed by a mask and a subsequent imperative target stimulus. With 'relevant' masks that are composed of the superposition of both prime alternatives, the inverse priming effect is typically larger than with 'irrelevant' masks that are free of task-relevant features. We used functional magnetic resonance imaging (fMRI) to examine the neural substrates that are involved in the generation of inverse priming effects with relevant and irrelevant masks. We found a network of brain areas that is accessible to unconscious primes, including supplementary motor area (SMA), anterior insula, middle cingulate cortex, and supramarginal gyrus. Activation of these brain areas were involved in inverse priming when relevant masks were used. With irrelevant masks, however, only SMA activation was involved in inverse priming effects. Activation in SMA correlated with inverse priming effects of individual participants on reaction time, indicating that this brain area reflects the size of inverse priming effects on the behavioral level. Findings are most consistent with the view that a basic inhibitory mechanism contributes to inverse priming with either type of mask and additional processes contribute to the effect with relevant masks. This study provides new evidence showing that cognitive control operations in the human cortex take account of task relevant stimulus information even if this information is not consciously perceived. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Examined response activation and inhibition in 18 Ss (mean age 33 yrs) to study executive control in a flanker task. Arrowheads pointing to the left or right served as targets and as congruent or incongruent flanker stimuli, using squares as neutral flanker stimuli. The onset of the flanker stimuli preceded that of the target stimuli by 100 msec. Motor responses were assessed by means of 2 analog devices. The EEG and electrooculogram (EOG) recordings were used for data analyses. Flanker compatibility exerted facilitative and interfering effects on performance. Increased spatial distance between target and flanker stimuli attenuated flanker compatibility effects on response times and error scores. Incongruent flanker condition provoked a N2c amplitude, which covaried with the magnitude of the erroneous response. The N2c, thus, corresponded to the avoidance of inappropriate responses, reflecting the inhibition of automatically but erroneously primed responses. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Studied motor inhibition using a hybrid choice-reaction go/no-go procedure involving selective response to clarify whether the N2 or the P3 or both event related potential (ERP) components indicate motor inhibition. 18 Ss (mean age 33 yrs), all being right-handed with normal to corrected-to-normal vision, performed the task. Response time and error measures as well as the lateralized readiness potential indicated that responses were primed by flanker stimuli that were associated with 1 of the 2 possible responses. In no-go trials, selective response priming influenced the N2 amplitude whereas the P3 amplitude was unaffected. Since the N2 appeared irrespective of whether an erroneous response was correctable or not, it is concluded that the N2 reflects either detection or the inhibition of an appropriate tendency to respond. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Unconscious stimuli can influence participants’ motor behavior but also more complex mental processes. Recent research has gradually extended the limits of effects of unconscious stimuli. One field of research where such limits have been proposed is spatial cueing, where exogenous automatic shifts of attention have been distinguished from endogenous controlled processes which govern voluntary shifts of attention. Previous evidence suggests unconscious effects on mechanisms of exogenous shifts of attention. Here, we applied a cue-priming paradigm to a spatial cueing task with arbitrary cues by centrally presenting a masked symmetrical prime before every cue stimulus. We found priming effects on response times in target discrimination tasks with the typical dynamic of cue-priming effects (Experiments 1 and 2) indicating that central symmetrical stimuli which have been associated with endogenous orienting can modulate shifts of spatial attention even when they are masked. Prime–Cue Congruency effects of perceptual dissimilar prime and cue stimuli (Experiment 3) suggest that these effects cannot be entirely reduced to perceptual repetition priming of cue processing. In addition, priming effects did not differ between participants with good and poor prime recognition performance consistent with the view that unconscious stimulus features have access to processes of endogenous shifts of attention. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

The processing of a visual target that follows a briefly presented prime stimulus can be facilitated if prime and target stimuli are similar. In contrast to these positive priming effects, inverse priming effects (or negative compatibility effects) have been found when a mask follows prime stimuli before the target stimulus is presented: Responses are facilitated after dissimilar primes. Previous studies on inverse priming effects examined target-priming effects, which arise when the prime and the target stimuli share features that are critical for the response decision. In contrast, 3 experiments of the present study demonstrate inverse priming effects in a nonmotor cue-priming paradigm. Inverse cue-priming effects exhibited time courses comparable to inverse target-priming effects. Results suggest that inverse priming effects do not arise from specific processes of the response system but follow from operations that are more general. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Apart from positive priming effects, masked prime stimuli can impair responses to a subsequent target stimulus which shares response-critical features in contrast to a target assigned to the opposite response. This counterintuitive phenomenon is called inverse priming (or negative compatibility effect). Here we examine the generality of this phenomenon beyond priming of motor responses. We used a non-motor cue-priming paradigm to study the underlying mechanism of inverse priming for relevant features masks which include task-relevant stimulus features and for irrelevant masks which omit task-relevant features. We found inverse cue-priming effects with both types of masks. With task-irrelevant masks inverse cue-priming was emphasized in those participants being unable to perceive the prime. The existence of inverse non-motor priming under conditions where simple perceptual interactions between the stimuli are ruled out as the source of inverse priming is at odds with the view that inverse priming reflects motor inhibition. Alternatives are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

The findings reported in this paper show that perceptual measures based on conscious reports do not suffice to determine whether some information is or is not available to the visual system at large. Instead, motor and perceptual effects can be become perfectly dissociated. This indicates that relevant stimulus attributes are fully processed up to the level of response control but remain unavailable for conscious report. It is also clear that classical psychophysical measures do not necessarily reflect all information available to the visual system, and they should be supplemented by performance measures that do not tap perceptual awareness. We believe that our approach of contrasting direct and indirect performance measures and of dissociating perception and action by their time courses may provide, in conjunction with neurophysiological and functional brain imaging approaches, a more complete picture of information processing within the visual system. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Motor responses can be facilitated by congruent visual stimuli and prolonged by incongruent visual stimuli that are made invisible by masking (direct motor priming). Recent studies on direct motor priming showed a reversal of these priming effects when a three-stimulus paradigm was used in which a prime was followed by a mask and a target stimulus was presented after a delay. A similar three-stimulus paradigm on nonmotor priming, however, showed no reversal of priming effects when the mask was used as a cue for processing of the following target stimulus (cue priming). Experiment 1 showed that the time interval between mask and target is crucial for the reversal of priming. Therefore, the time interval between mask and target was varied in three experiments to see whether cue priming is also subject to inhibition at a certain time interval. Cues indicated (1) the stimulus modality of the target stimulus, (2) the task to be performed on a multidimensional auditory stimulus, or (3) part of the motor response. Whereas direct motor priming showed the reversal of priming about 100 msec after mask presentation, cue priming effects simply decayed during the 300 msec after mask presentation. These findings provide boundary conditions for accounts of inverse priming effects. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

When participants must respond to a relevant central target and ignore irrelevant flanking stimuli, the flankers produce a flanker compatibility effect on behavioural measures. Current accounts of the flanker compatibility effect assume that both target and flanker stimuli affect response activation. This idea is supported by electrophysiological studies, which show that irrelevant flanker stimuli can affect the motor system. The present experiments examined the characteristics of flanker effects on the motor system by analysing the details of the motor output with response force measures. A total of 60 participants responded in the flanker task to arrows (Experiment 1) or letters (Experiment 2). Reaction time as well as response force increased on incompatible trials. Analyses of the distribution of incorrect activation revealed that both response times and correct motor output increased with the amount of incorrect activity. However, the flanker compatibility effect was only marginally modulated by incorrect activity. Results suggest that the largest part of the flanker compatibility effect cannot be attributed to response activation and competition at late levels of the response system. [ABSTRACT FROM AUTHOR]

Der Abstract-Band zur 42. Tagung experimentell arbeitender Psychologen vom 3. bis 6. April 2000 in Braunschweig enthält 405 Kurzbeiträge aus Symposien, Referate- und Postergruppen. Die Beiträge verteilen sich auf folgende Themenfelder: (A) Referate. (1) Wahrnehmung, Aufmerksamkeit und Handlung (Wahrnehmung; auditive Wahrnehmung; visuelle Psychophysik; visuelle Suche; Aufmerksamkeit; exekutive Kontrolle; kognitive Kontrolle und Handungsplanung; Informationsverarbeitung und kognitive Kontrolle; Handlungseffekte; Psychomotorik). (2) Lernen und Gedächtnis (Lernen und Konditionieren, Gedächtnis, implizite kognitive Prozesse). (3) Motivation und Emotion. (4) Denken, Wissen und Sprache (Lesen und Worterkennung; Sprachproduktion; Wissenspsychologie; Denken und Problemlösen; Raumkognition). (5) Sozialpsychologie (selbstbezogene Kognition; emotionale Prozesse und soziale Aktivierung; Glaubwürdigkeit und Persuasion; soziale Schlüsse und Kategorien; Hilfsbereitschaft und soziale Wahrnehmung). (6) Klinische Psychologie, Diagnostik und Forschungsmethoden. (7) Biologische Psychologie. (8) Entwicklungspsychologie. (9) Verkehrspsychologie. (B) Symposien (Urteilsverzerrungen; implizite Messverfahren; kognitive Varianten bei verschiedenen Patientengruppen und Hirngesunden; Mehr-Komponenten-Konzeption von Einstellungen). (C) Poster. (10) Wahrnehmung, Aufmerksamkeit und Handlung (Wahrnehmung, Gesichtererkennung; Textursegmentierung und visuelle Suche; Aufmerksamkeitsmechanismen; kognitive Kontrolle; Psychomotorik). (11) Lernen und Gedächtnis (implizite kognitive Prozesse; Gedächtnis). (12) Denken, Wissen und Sprache (Denken, Problemlösen und Wissenspsychologie; Raumkognition; mentale Rotation; Worterkennung und Lesen; Psycholinguistik). (13) Beeinträchtigte kognitive Funktionen. (14) Sozialpsychologie. (15) Diagnostik und Forschungsmethodik. (15) Biopsychologie.

When participants must respond to a relevant central target and ignore irrelevant flanking stimuli the flanking stimuli produce a compatibility effect, with increased response speed and accuracy on compatible as compared to incompatible trials. This flanker effect is larger when compatible trials are more frequent than incompatible trials (the ratio effect). A potential explanation of this ratio effect is that the occurrence of frequent incompatible trials causes the focus of spatial attention to be set narrower than when there are frequent compatible trials. The present investigation tests this hypothesis by comparing the flanker effect with near and far flankers. The hypothesis predicts that the flanker distance should modulate the ratio effect more when incompatible trials are frequent than when compatible trials are frequent. The results, however, show the opposite pattern: Distance effects are larger in conditions with frequent compatible trials. Moreover, the effect of distance but not the ratio effect was eliminated when flanker distance remained fixed across blocks of trials, and also when participants had to attend to flanker stimuli in a go-no-go task. These results suggest that the ratio effect does not result from an adjustment of the focus of spatial attention. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Visual stimuli may remain invisible but nevertheless produce strong and reliable effects on subsequent actions. How well features of a masked prime are perceived depends crucially on its physical parameters and those of the mask. We manipulated the visibility of masked stimuli and contrasted it with their influence on the speed of motor actions, comparing the temporal dynamics of visual awareness in metacontrast masking with that of action priming under the same conditions. We observed priming with identical time course for reportable and invisible prime stimuli, despite qualitative changes in the masking time course. Our findings indicate that experimental variations that modify the subjective visual experience of masked stimuli have no effect on motor effects of those stimuli in early processing. We propose a model that provides a quantitative account of priming effects on response speed and accuracy.

The present experiments further examined the characteristics of flanker effects on the motor system. 60 participants responded in the flanker task to arrows (Experiment 1) or letters (Experiment 2). To examine time and extent of flanker effects on the motor system, target onset was delayed with blocked or random stimulus onset asynchronies (SOA). With SOA of 0 and 100 ms, flanker effects on behavioral measures were reduced in random as compared to blocked conditions, but enhanced with SOA of 400 ms. With SOA of 400 ms, flanker effects on the early lateralized readiness potentials (LRP) were reduced in blocked as compared to random conditions, indicating that the onset of flanker effects on the LRP was delayed. Response-locked LRPs suggest that flanker and target stimuli activate the motor system successively. Findings challenge current theories of the flanker compatibility effect.

When observers view a rapidly moving stimulus they may see only a static streak. We report that there can be a transient percept of motion if such a moving stimulus is preceded or followed by a stationary image of that stimulus. A ring of dots was rotated so rapidly observers only saw a continuous outline circle and could not report its rotation direction. When an objectively stationary ring of dots preceded or followed this rotating ring, the stationary ring appeared to visibly launch into motion from a standstill or visibly rotate to a halt, principally in the same direction as the actual rapid rotation. Thus, motions too rapid to be consciously perceived as motion can nonetheless be processed by the visual system, and generate neural transition states that are consciously experienced as motion percepts. We suggest such transition states might serve a unifying function by bridging discontinuous motion states. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

A central question regarding the nature of cognitive control is the extent to which different tasks are controlled by a common system. We addressed this issue by comparing the cortical activation associated with the processing of an invalidly cued event with the activation associated with a validly cued event. In a perceptual cueing task, we cued the likely stimulus modality (visual or auditory), and in a motor cueing task, we cued the likely motor response (left or right hand). Event-related functional MRI revealed increased activation in the anterior cingulate cortex on valid and invalid trials in both tasks. In addition, a network of six regions, including the dorsal medial frontal cortex, showed increased activation on invalid trials irrespective of whether the invalid cue referred to the stimulus modality or response. Findings suggest that dorsal medial frontal cortex rather than the anterior cingulated cortex is involved in conflict monitoring operations. We summarize our findings in a model that links six modules for processing invalidly cued events. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

The interaction of two expectancies was examined. These were either two perceptual or two response-related expectancies. Perceptual expectancies were induced by combining spatial cuing with feature cuing on a trial-by-trial basis. Cues consisted either of two integrated parts, such as two arrows, or two separated pieces, such as an arrow and a word. Spatial-cuing effects were reduced on trials with invalid feature cues, as compared with valid ones. However, the interaction of spatial cuing and feature cuing was modulated by the type of cue used to induce expectancies. With integrated cues, spatial-cuing effects were reduced about twice as much as with separated cues. The same effect of type of cue was found in Experiment 2, although finger cuing was combined with hand cuing. With integrated cues, finger-cuing effects were much smaller on trials with invalid hand cues, as compared with valid ones. With separated cues, however, finger-cuing effects were additive to hand-cuing effects. The similarity of the results within perceptual- and motor-cuing tasks suggests that a general principle governs the combination of expectancies, such as that outlined in the framework of the proposed adjusted expectancy model. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

When participants use cues to prepare for a likely stimulus or a likely response, reaction times are facilitated by valid cues but prolonged by invalid cues. In studies on combined expectancy effects, two cues give information regarding two dimensions of the forthcoming task. When the two cues consist of two separable stimuli their effects are approximately additive. When cues are presented as an integrated stimulus, cueing effects interact. A model is presented that simulates effects like these. The model assumes that cues affect different processing stages. When implicit information suggests that expectancies are unrelated, as for instance with separated cues, cueing effects at early and late levels of processing remain independent. When implicit information suggests that expectancies are related, as with integrated cues, however, a mechanism that is sensitive to the validity of the early stage cue, leads to an adjustment of the cueing effect at the late stage. The model is based on neurophysiologically plausible assumptions, it is given explicitly in mathematical terms, and it provides a good fit to a large body of empirical data. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Studies of combined expectancies have shown that spatial cueing effects are reduced on trials on which participants have to respond with an unexpected motor response. In the first two experiments the range of reduced expectancy effects is examined. Advance knowledge of the likely response was combined in a trial-by-trial procedure with modality cueing, object cueing, and task cueing. Effects of modality cueing were reduced on trials on which the target requested an unexpected response. However, effects of object cueing as well as effects of task cueing were unaffected by response cueing. Comparing experiments revealed that different types of cues were used in different experiments. To test the effect of type of cue on the interaction of expectancies the third experiment combined spatial cueing with response cueing. When integrated cues were used that cued the likely target location by an arrow and the likely response by an arrow too, spatial cueing effects were reduced on trials with unexpected responses. However, spatial cueing effects remained unaffected by response cueing when separated cues were used consisting in a word cueing the response and an arrow cueing target location. An account for the modulation of combined expectancies by the relation between cues is suggested in terms of the adjusted expectancy model. [ABSTRACT FROM AUTHOR]