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Action preparation helps and hinders perception of action
Several theories of the mechanisms linking perception and action require that the links are bidirectional, but there is a lack of consensus on the effects that action has on perception. We investigated this by measuring visual event-related brain potentials to observed hand actions while participants prepared responses that were spatially compatible (e.g., both were on the left side of the body) or incompatible and action type compatible (e.g., both were finger taps) or incompatible, with observed actions. An early enhanced processing of spatially compatible stimuli was observed, which is likely due to spatial attention. This was followed by an attenuation of processing for both spatially and action type compatible stimuli, likely to be driven by efference copy signals that attenuate processing of predicted sensory consequences of actions. Attenuation was not response-modality specific; it was found for manual stimuli when participants prepared manual and vocal responses, in line with the hypothesis that action control is hierarchically organized. These results indicate that spatial attention and forward model prediction mechanisms have opposite, but temporally distinct, effects on perception. This hypothesis can explain the inconsistency of recent findings on action–perception links and thereby supports the view that sensorimotor links are bidirectional. Such effects of action on perception are likely to be crucial, not only for the control of our own actions but also in sociocultural interaction, allowing us to predict the reactions of others to our own actions
Links between eye movement preparation and the attentional processing of tactile events: An event-related brain potential study
Objective
We investigated whether the covert preparation of saccadic eye movements results in spatially specific modulations of somatosensory processing.
Methods
ERPs were recorded in a spatial cueing experiment where auditory cues preceded tactile stimuli delivered to the left or right hand. In the Saccade task, cues signalled that an eye movement towards the left or right hand had to be prepared. In the Covert Attention task, cues signalled the direction of a covert shift of tactile attention.
Results
A lateralized component previously observed during cued shifts of spatial attention (ADAN) was elicited in the cue–target interval in both tasks. The somatosensory N140 component was enhanced for tactile stimuli presented to the hand on the cued side. This modulation was present not just in the Covert Attention task, but also in the Saccade task. Longer-latency effects of spatial cueing were only present in the Covert Attention task.
Conclusions
Covert shifts of attention and saccade preparation have similar effects on early stages of tactile processing, suggesting that both are mediated by overlapping control processes.
Significance
These findings support the premotor theory of attention by demonstrating that the programming of eye movements has spatially selective effects on somatosensory processing
Active listening impairs visual perception and selectivity: an ERP study of auditory dual-tasks costs on visual attention
The ability to drive safely is disrupted by cell phone conversations, and this has been attributed to a diversion of attention from the visual environment. We employed behavioral and ERP measures to study whether the attentive processing of spoken messages is, in itself, sufficient to produce visual–attentional deficits. Participants searched for visual targets defined by a unique feature (Experiment 1) or feature conjunction (Experiment 2), and simultaneously listened to narrated text passages that had to be recalled later (encoding condition), or heard backward-played speech sounds that could be ignored (control condition). Responses to targets were slower in the encoding condition, and ERPs revealed that the visual processing of search arrays and the attentional selection of target stimuli were less efficient in the encoding relative to the control condition. Results demonstrate that the attentional processing of visual information is impaired when concurrent spoken messages are encoded and maintained, in line with cross-modal links in selective attention, but inconsistent with the view that attentional resources are modality-specific. The distraction of visual attention by active listening could contribute to the adverse effects of cell phone use on driving performance
Sensory consequences of directing attention and action to opposite locations. Cognitive Neuroscience Society (CNS), San Francisco, USA.
Manual response preparation disrupts spatial attention: an electrophysiological investigation of links between action and attention
Previous behavioural and neuroscience studies have shown that the systems involved in the control of attention and action are functionally and anatomically linked. We used behavioural and event-related brain potential measures to investigate whether such links are mandatory or merely optional. Cues presented at the start of each trial instructed participants to shift attention to the left or right side and to simultaneously prepare to a finger movement with their left or right hand. In different trials, cues were followed by a central Go signal, requiring execution of the prepared manual response (motor task), or by a peripheral visual stimulus, which required a target–non-target discrimination only when presented on the cued side (attention task). Lateralised ERP components indicative of covert attention shifts were found when attention and action were directed to the same side (same side condition), but not when attention and action were directed to opposite sides (opposite sides condition). Likewise, effects of spatial attention on the processing of peripheral visual stimuli were present only when attention and action were directed to the same side, but not in the opposite sides condition. These results demonstrate that preparing a manual response on one side severely disrupts the attentional selection of visual stimuli on the other side, and suggest that it is not possible to simultaneously direct attention and action to different locations in space. They support the hypothesis that the control of spatial attention and action are implemented by shared brain circuits, and are therefore linked in a mandatory fashion
La pianificazione di movimenti oculari e’ in grado di indurre spostamenti dell’attentione? (Are shifts of attention elicited during covert eye movement preparation?). National Congress of the Italian Psychological Society, Division of Experimental Psychology, Como.
Eye movement preparation causes spatially-specific modulation of auditory processing: New evidence from event-related brain potentials
To investigate whether saccade preparation can modulate processing of auditory stimuli in a spatially-specific fashion, ERPs were recorded for a Saccade task, in which the direction of a prepared saccade was cued, prior to an imperative auditory stimulus indicating whether to execute or withhold that saccade. For comparison, we also ran a conventional Covert Attention task, where the same cue now indicated the direction for a covert endogenous attentional shift prior to an auditory target-nontarget discrimination. Lateralised components previously observed during cued shifts of attention (ADAN, LDAP) did not differ significantly across tasks, indicating commonalities between auditory spatial attention and oculomotor control. Moreover, in both tasks, spatially-specific modulation of auditory processing was subsequently found, with enhanced negativity for lateral auditory nontarget stimuli at cued versus uncued locations. This modulation started earlier and was more pronounced for the Covert Attention task, but was also reliably present in the Saccade task, demonstrating that the effects of covert saccade preparation on auditory processing can be similar to effects of endogenous covert attentional orienting, albeit smaller. These findings provide new evidence for similarities but also some differences between oculomotor preparation and shifts of endogenous spatial attention. They also show that saccade preparation can affect not just vision, but also sensory processing of auditory events
Dissociating effector and movement direction selection during the preparation of manual reaching movements: Evidence from lateralized ERP components
Objective
The present study investigated whether lateralized ERP components triggered during covert manual response preparation (ADAN, LDAP) reflect effector selection, the selection of movement direction, or both.
Methods
Event-related brain potentials were recorded during a response precueing paradigm where visual cues provided either partial (Experiment 1) or full (Experiment 2) information about the response hand and the direction for a subsequent reaching movement.
Results
ADAN and LDAP components were elicited even when only partial response information was available, demonstrating that they do not require the presence of a fully specified motor program. The ADAN was elicited in a similar fashion regardless of whether effector or movement direction information was provided, suggesting that the underlying mechanisms are equally sensitive to both types of response-related information. In contrast, the LDAP was larger in response to cues providing effector information, but was also reliably present when movement direction was available.
Conclusions
ADAN and LDAP components reflect preparatory activity within anterior and posterior parts of the parieto-premotor sensorimotor network where different parameters for manual reaching movements are programmed independently.
Significance
These results support the claim of the premotor theory of attention that shared sensorimotor control mechanisms are involved in attention and motor programming
ERP effects of movement preparation on visual processing: attention shifts to the hand, not the goal
Do ERP components triggered during attentional orienting represent supramodal attentional control?
Lateralized ERP components triggered during cued shifts of spatial attention (anterior directing attention negativity [ADAN], late directing attention positivity [LDAP]) have been observed during visual, auditory, and tactile attention tasks, suggesting that these components reflect supramodal attentional control processes. This interpretation has recently been called into question by the finding that the ADAN is absent in response to auditory attention cues. Here we demonstrate that ADAN and LDAP components are reliably elicited in a purely unimodal auditory attention task where auditory cues are followed by auditory imperative stimuli. The fact that the ADAN is not restricted to task contexts where visual or tactile stimuli are relevant is consistent with the hypothesis that this component is linked to supramodal attentional control
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