Semantic integration and context

Context effects in recognition memory were examined by manipulating the semantic integration of sentential contexts. Subjects studied words embedded in congruous, incongruous, and anomalous sentences and were tested for recognition of the targets in either the same or changed contexts. Recognition was impaired if the test item appeared in a new sentence, and the extent of the decrement was greatest for congrous sentences. The results suggest that consistence with past experience affects the integration of the representation, and that the stronger the integration, the more difficult it is to recognize the target in a new context. The data are discussed in terms of a relative specificity of encoding effect.     

Semantic activation in action planning

Four experiments investigated activation of semantic information in action preparation. Participants either prepared to grasp and use an object (e.g., to drink from a cup) or to lift a finger in association with the object's position following a go/no-go lexical-decision task. Word stimuli were consistent to the action goals of the object use (Experiment 1) or to the finger lifting (Experiment 2). Movement onset times yielded a double dissociation of consistency effects between action preparation and word processing. This effect was also present for semantic categorizations (Experiment 3), but disappeared when introducing a letter identification task (Experiment 4). In sum, our findings indicate that action semantics are activated selectively in accordance with the specific action intention of an actor.     

Temporal integration and contrast sensitivity in foveal and peripheral vision

Spatial contrast sensitivity functions and temporal integration functions for gratings with dark surrounds were measured at various eccentricities in photopic vision. Contrast sensitivity decreased with increasing eccentricity at all exposure durations and spatial frequencies tested. The decrease was faster at high than at low spatial frequencies, but similar at different exposure durations. When cortically similar stimulus conditions were produced at different eccentricities by M-scaling, contrast sensitivity became independent of visual field location at all exposure durations tested. The results support the view that in photopic vision spatiotemporal information processing is qualitatively similar across the visual field, and that quantitative differences result from retino-topical differences in ganglion cell sampling. For gratings of constant retinal area temporal integration (improvement of contrast sensitivity with increasing exposure duration) was more extensive at high than at low retinal spatial frequencies but independent of cortical spatial frequency and eccentricity. For M-scaled gratings temporal integration was more extensive at high than at low cortical spatial frequencies but independent of retinal spatial frequency and eccentricity. The results suggest that the primary determinant of temporal integration is not spatial frequency but grating value that is calculated as AF2 square cycles (cycle2), where A is grating area and F spatial frequency.     

Electrophysiological examination of embodiment in vision and action

A wealth of behavioral data has shown that the visual properties of objects automatically potentiate motor actions linked with them, but how deeply are these affordances embedded in visual processing? In the study reported here, we used electrophysiological measures to examine the time course of affordance resulting from the leftward or rightward orientation of the handles of common objects. Participants were asked to categorize those objects using a left- or right-handed motor response. Lateralized readiness potentials showed rapid motor preparation in the hand congruent with the affordance provided by the object only 100 to 200 ms after stimulus presentation and up to 400 ms before the actual response. Examination of event-related potentials also revealed an effect of handle orientation and response-hand congruency on the visual P1 and N1 components. Both of these results suggest that activity in the early sensory pathways is modulated by the action associations of objects and the intentions of the viewer.     

Vision for perception and vision for action: normal and unusual development

Evidence suggests that visual processing is divided into the dorsal ('how') and ventral ('what') streams. We examined the normal development of these streams and their breakdown under neurological deficit by comparing performance of normally developing children and Williams syndrome individuals on two tasks: a visually guided action ('how') task, in which participants posted a card into an oriented slot, and a perception ('what') task, in which they matched a card to the slot's orientation. Results showed that all groups performed worse on the action task than the perception task, but the disparity was more pronounced in WS individuals and in normal 3-4-year-olds than in older children. These findings suggest that the 'how' system may be relatively slow to develop and more vulnerable to breakdown than the 'what' system.     

Dissociations between vision for perception and vision for action depend on the relative availability of egocentric and allocentric information

In three experiments, we scrutinized the dissociation between perception and action, as reflected by the contributions of egocentric and allocentric information. In Experiment 1, participants stood at the base of a large-scale one-tailed version of a Müller-Lyer illusion (with a hoop) and either threw a beanbag to the endpoint of the shaft or verbally estimated the egocentric distance to that location. The results confirmed an effect of the illusion on verbal estimates, but not on throwing, providing evidence for a dissociation between perception and action. In Experiment 2, participants observed a two-tailed version of the Müller-Lyer illusion from a distance of 1.5 m and performed the same tasks as in Experiment 1, yet neither the typical illusion effects nor a dissociation became apparent. Experiment 3 was a replication of Experiment 1, with the difference that participants stood at a distance of 1.5 m from the base of the one-tailed illusion. The results indicated an illusion effect on both the verbal estimate task and the throwing task; hence, there was no dissociation between perception and action. The presence (Exp. 1) and absence (Exp. 3) of a dissociation between perception and action may indicate that dissociations are a function of the relative availability of egocentric and allocentric information. When distance estimates are purely egocentric, dissociations between perception and action occur. However, when egocentric distance estimates have a (complementary) exocentric component, the use of allocentric information is promoted, and dissociations between perception and action are reduced or absent.     

Temporal integration in vision: Masking can aid detection

Temporal form-part integration is the process whereby two discrete sets of stimuli, presented at different times, are perceived by the visual system as a single integrated percept. Dixon and Di Lollo (Cognitive Psychology 26(1):33-63, 1994) proposed a temporal correlation model that was able to quantitatively account for a number of findings related to both form-part integration tasks and partial report. The present study demonstrates a novel approach to form-part integration—the addition of a whole-field mask stimulus at the termination of the second set of stimuli. According to an extension of the correlation model, the mask stimulus should reduce the visual system’s response to the trailing display, thus increasing the relative overlap of the two displays, fostering integration. Experiment 1 supported this hypothesis, showing a maximum benefit when the mask followed the trailing display immediately, as opposed to after a delay of 60 ms. Experiment 2 showed that this same mask actually did yield worse performance when presented immediately after a single set of stimuli. The third experiment collected detailed data for a few observers over a larger number of mask delays. Taken together, these experiments provide a rare example of masking degrading a target stimulus, and yet aiding perception.     

Semantic distance effects on object and action naming

Graded interference effects were tested in a naming task, in parallel for objects and actions. Participants named either object or action pictures presented in the context of other pictures (blocks) that were either semantically very similar, or somewhat semantically similar or semantically dissimilar. We found that naming latencies for both object and action words were modulated by the semantic similarity between the exemplars in each block, providing evidence in both domains of graded semantic effects.     

Multisensory integration of vision and touch in nonspatial feature discrimination tasks

Multisensory integration of nonspatial features between vision and touch was investigated by examining the effects of redundant signals of visual and tactile inputs. In the present experiments, visual letter stimuli and/or tactile letter stimuli were presented, which participants were asked to identify as quickly as possible. The results of Experiment 1 demonstrated faster reaction times for bimodal stimuli than for unimodal stimuli (the redundant signals effect (RSE)). The RSE was due to coactivation of figural representations from the visual and tactile modalities. This coactivation did not occur for a simple stimulus detection task (Experiment 2) or for bimodal stimuli with the same semantic information but different physical stimulus features (Experiment 3). The findings suggest that the integration process might occur at a relatively early stage of object-identification prior to the decision level.     

Semantic integration of verbal information into a visual memory

A total of 1,242 subjects, in five experiments plus a pilot study, saw a series of slides depicting a single auto-pedestrian accident. The purpose of these experiments was to investigate how information supplied after an event influences a witness's memory for that event. Subjects were exposed to either consistent, misleading, or irrelevant information after the accident event. Misleading information produced less accurate responding on both a yes-no and a two-alternative forced-choice recognition test. Further, misleading information had a larger impact if introduced just prior to a final test rather than immediately after the initial event. The effects of misleading information cannot be accounted for by a simple demand-characteristics explanation. Overall, the results suggest that information to which a witness is exposed after an event, whether that information is consistent or misleading, is integrated into the witness's memory of the event.     

Mechanisms of percept-percept and image-percept integration in vision: behavioral and electrophysiological evidence

Previous research has shown that the detection of a visual target can be guided not only by the temporal integration of two percepts, but also by integrating a percept and an image held in working memory. Behavioral and event-related brain potential (ERP) measures were obtained in a target detection task that required temporal integration of 2 successively presented stimuli in the left or right hemifield. Task performance was good when both displays followed each other immediately (percept-percept integration) and when displays were separated by a 300- or 900-ms interval (image-percept integration), but was poor with intermediate interstimulus intervals. An enhanced posterior negativity at electrodes contralateral to the side of the target was observed for percept-percept and for image-percept integration, demonstrating that both are based on spatiotopic representations. However, this contralateral negativity emerged later and was more sustained on trials with long interstimulus intervals, indicating that image-percept integration is slower and involves a sustained activation of working memory.     

Semantic integration in children's reconstruction of narrative sequences

Preschool to fourth grade subjects were required to reconstruct a previously seen logical sequence by selecting old items from a set containing actually seen events and two types of new items, those consistent or inconsistent with the ordered sequence of the story. Older children were more efficient at adopting a consistent choice strategy, at rejecting inconsistent items and at retaining the end-anchor items of the story. When performance on the old anchor items was excluded, however, all grades had difficulty distinguishing the new-consistent items from the actually experienced old items. It is suggested that memory for logical narrative sequences involves the retention of the gist or theme in an integrated unified representation of the meaning rather than a series of discrete events. Further, the underlying processes of integration and inference are stable across ages.     

Semantic and phonological performance in adults learning novel object and action words

Twenty normal adults participated in two training sessions designed to teach eight novel object words and eight novel action words. Each subject received comprehension and production training and was probed at the end of each session to determine the ability to retrieve lexical items in a naming task. The probe data were also analyzed for phonological accuracy. Reaction time measures for the production probes were recorded to determine differences between action and object words in terms of retrieval difficulty. The results demonstrated a significant difference in early learning of action and object words during comprehension training and production training and in production probes. Object words tended to be learned more easily in both comprehension and production training, and they were retrieved correctly more often in production probes. There were no significant differences in the phonological accuracy between the word types. Reaction time data indicated significant differences in early as well as later learning between action and object words, with object words having significantly shorter rection times as compared with action words. Results are discussed in the context of prior research.     

The role of integration in recognition failure and action memory

In three experiments, we studied memory for action events with respect to exceptions from the Tulving-Wiseman function demonstrated in experiments on recognition failure of recallable words. In Experiment 1, we examined exceptions of poor integration in a regular recognition failure condition (i.e., recognition of targets without contextual cues, followed by recall of targets in the presence of contextual cues). In Experiment 2, we examined exceptions of cue overlap in which subjects also had access to the information of contextual cues at recognition test. In Experiment 3, we attempted to equate the levels of recognition across the action and verbal encoding. In addition, the cue overlap and no-cue overlap conditions were studied in a within-subjects design. Results from the three experiments indicated that encoding enactment (episodic integration) and conceptual integration (semantic integration) are related to each other. As a consequence of this relationship, there is a larger independence between recognition and recall of well-integrated items with encoding enactment. On the other hand, for the poorly integrated items without encoding enactment, there is a larger dependence between recognition and recall. Even in the cue overlap condition, where there is a case of large dependence between recognition and recall, the same pattern of data was observed. The results are discussed in terms of an episodic integration view of encoding enactment.     

The case for causal influences of action videogame play upon vision and attention

Over the past decade, exciting findings have surfaced suggesting that routine action videogame play improves attentional and perceptual skills. Apparently, performance during multiple-object tracking, useful-field-of-view tests, and task switching improves, contrast sensitivity and spatial-resolution thresholds decrease, and the attentional blink and backward masking are lessened by short-term training on action videogames. These are remarkable findings showing promise for the training of attention and the treatment of disorders of attentional function. While the findings are interesting, evidence of causal influences of videogame play is not as strong as is often claimed. In many studies, observers with game play experience and those without are tested. Such studies do not address causality, since preexisting differences are not controlled for. Other studies investigate the training of videogame play, with some evidence of training benefits. Methodological shortcomings and potential confounds limit their impact, however, and they have not always been replicated. No longitudinal studies on videogame training exist, but these may be required to provide conclusive answers about any benefits of videogame training and any interaction with preexisting differences. Suggestions for methodological improvement are made here, including recommendations for longitudinal studies. Such studies may become crucial for the field of attentional training to reach its full potential.     

Enacting collective support for the European integration: Participation in pro‐integration action and preference for specific transnational acculturation strategies

We propose that collective support for European integration is mani‐fested in 2 distinct forms: first, as engagement in socio‐political action by citizens who seek to change their nation and its status in Europe. Second, it is manifested as a transnational acculturation process that impacts on both nations and their citizens. These processes potentially engage social identities at 3 levels: national, European and as supporters of the European integration. Here, we examine these different levels of identification as part of a model predicting collective support for the European integration. To capture the dimension of transnationality, we collected data from 2 Romanian samples, 1 of participants living in their country of origin (N = 203), and 1 of participants living as migrants outside Romania (N = 196). We found that identification as a pro‐integration supporter flows from European and Romanian national identifications and is an excellent predictor of collective support for European integration in both its forms. We conclude by discussing how our findings can be applied to the design of intervention strategies and policies to promote support for the European Union and the integration process in the current socio‐political climate (where the unity and the very existence of European Union are under threat).