Section 2: Multisensory integration.

Introduces a section of this Special Edition in Cognitive Neuroscience, which examines the neural mechanisms and cognitive factors that influence the formation of multimodal percepts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibition of return: Dissociating attentional and oculomotor components.

Inhibition of return (IOR) describes a performance decrement for stimuli appearing at recently cued locations. Both attentional and motor processes have been implicated in the IOR effect. The present data reveal a double dissociation between the attentional and motor components of IOR whereby the motor-based component of IOR is present when the response is oculomotor, and the attention-based component of IOR is present when the response is manual. These 2 distinct components should be considered and studied separately, as well as in relation to each other, if a comprehensive theory of IOR is to be achieved. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The psychological refractory period effect following callosotomy: Uncoupling of lateralized response codes.

A callosotomy patient was tested in 2 dual-task experiments requiring successive speeded responses to lateralized stimuli. The patient showed a robust psychological refractory period (PRP) effect. Three aspects of the data indicate that, unlike for the control participants, the PRP effect for the split-brain patient should not be attributed to a response selection bottleneck. First, the patient did not show an increase in reaction time (RT) when the 2 tasks required responses from a common output system compared with when different output systems were used. Second, inconsistent stimulus-response mappings for the 2 tasks increased RTs for the control participants but had minimal effect on the performance of the split-brain patient. Third, the consistency manipulation was underadditive with stimulus onset asynchrony but was additive or overadditive for the normal participants. These results suggest that the persistent PRP effect following callosotomy should be attributed to a bottleneck associated with response initiation, a strategy adopted to comply with the task demands, or a combination of these factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Environmentally defined frames of reference: Their time course and sensitivity to spatial cues and attention.

In a Simon task the effects of spatial cues and attention on spatial stimulus coding were explored. Participants made speeded responses corresponding to the direction of target arrows that were preceded by peripherally presented cues. Cue validity varied across experiments as did the percentage of trials on which the target appeared peripherally or centrally. The data indicate (a) that targets are coded relative to multiple reference frames, (b) that spatial coding of a target is not affected when attention is shifted to the target, and (c) that an object serves as a referent for spatial coding of other objects even after its spatial code no longer activates responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Special edition in cognitive neuroscience: Preface.

Introduces this special issue of the Canadian Journal of Experimental Psychology, which focuses on three "hot" research areas in Cognitive Neuroscience--perception and action, multisensory integration, memory and higher-order cognition. Highlighted within each domain is how different research methodologies can be brought to bear on the issue of the neural bases of higher mental functions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cross-Modal Dynamic Capture: Congruency Effects in the Perception of Motion Across Sensory Modalities.

This study investigated multisensory interactions in the perception of auditory and visual motion. When auditory and visual apparent motion streams are presented concurrently in opposite directions, participants often fail to discriminate the direction of motion of the auditory stream, whereas perception of the visual stream is unaffected by the direction of auditory motion (Experiment 1). This asymmetry persists even when the perceived quality of apparent motion is equated for the 2 modalities (Experiment 2). Subsequently, it was found that this visual modulation of auditory motion is caused by an illusory reversal in the perceived direction of sounds (Experiment 3). This "dynamic capture" effect occurs over and above ventriloquism among static events (Experiments 4 and 5), and it generalizes to continuous motion displays (Experiment 6). These data are discussed in light of related multisensory phenomena and their support for a "modality appropriateness" interpretation of multisensory integration in motion perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Predictability influences stopping and response control.

Using a continuous tracking task, the authors examined whether stopping is resistant to expectancies as well as whether it is a representative measure of response control. Participants controlled the speed of a moving marker by continuously adjusting their response force. Participants stopped their ongoing tracking in response to auditory signals on 25%, 50%, 75%, or 100% of trials. Stopping was contrasted with accelerating, in which participants accelerated the marker in response to the signals. In Experiment 1, on each trial participants either stopped or accelerated, allowing a trade-off between the two. In Experiments 2 and 3, participants only stopped or only accelerated, thus decreasing the likelihood of a trade-off. When a trade-off was possible, stopping was resistant to expectancies. However, with little or no trade-off, expectancies influenced stopping and accelerating similarly. These findings contrast with the established view that stopping is insensitive to expectancies. In addition, when trade-offs are prevented, these results confirm that stopping is representative of other response adjustment measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional Effects of Counterpredictive Gaze and Arrow Cues.

The authors used counterpredictive cues to examine reflexive and volitional orienting to eyes and arrows. Experiment 1 investigated the effects of eyes with a novel design that allowed for a comparison of gazed-at (cued) target locations and likely (predicted) target locations against baseline locations that were not cued and not predicted. Attention shifted reflexively to the cued location and volitionally to the predicted location, and these 2 forms of orienting overlapped in time. Experiment 2 discovered that another well-learned directional stimulus, an arrow, produced a different effect: Attention was shifted only volitionally to the predicted location. The authors suggest that because there is a neural architecture specialized for processing eyes, gaze-triggered attention is more strongly reflexive than orienting to arrows. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Section 2: Intégration multisensorielle.

Introduces a section of this Special Edition in Cognitive Neuroscience, which examines the neural mechanisms and cognitive factors that influence the formation of multimodal percepts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)