Sensory ERP effects in auditory distraction: did we miss the main event?

Event-related potentials (ERPs) offer unique insights into processes related to involuntary attention changes triggered by rare, unpredictably occurring sensory events, that is, distraction. Contrasting ERPs elicited by distracters and frequent standard stimuli in oddball paradigms allowed the formulation of a three-stage model describing distraction-related processing: first, the distracting event is highlighted by a sensory filter. Second, attention is oriented towards the event, and finally, the task-optimal attention set is restored, or task priorities are changed. Although this model summarizes how distracting stimulus information is processed, not much is known about the cost of taking this exceptional route of processing. The present study demonstrates the impact of distraction on sensory processing. Participants performed a Go/NoGo tone-duration discrimination task, with infrequent pitch distracters. In the two parts of the experiment the duration-response mapping was reversed. Contrasts of distracter and standard ERPs revealed higher P3a- and reorienting negativity amplitudes for short than for long tones, independently from response type. To understand the cause of these asymmetries, short vs. long ERP contrasts were calculated. The ERP pattern showed that short standards elicited an attention-dependent offset response, which was abolished for short distracters. That is, the apparent P3a- and RON enhancements were caused by the removal of a task-related attentional sensory enhancement. This shows that the disruption of task-optimal attention set precedes the elicitation of the P3a, which suggests that P3a does not reflect a process driving the initial distraction-related attention change

Faster maturation of selective attention in musically trained children and adolescents : Converging behavioral and event-related potential evidence

Previous work suggests that musical training in childhood is associated with enhanced executive functions. However, it is unknown whether this advantage extends to selective attention-another central aspect of executive control. We recorded a well-established event-related potential (ERP) marker of distraction, the P3a, during an audio-visual task to investigate the maturation of selective attention in musically trained children and adolescents aged 10-17 years and a control group of untrained peers. The task required categorization of visual stimuli, while a sequence of standard sounds and distracting novel sounds were presented in the background. The music group outperformed the control group in the categorization task and the younger children in the music group showed a smaller P3a to the distracting novel sounds than their peers in the control group. Also, a negative response elicited by the novel sounds in the N1/MMN time range (similar to 150-200 ms) was smaller in the music group. These results indicate that the music group was less easily distracted by the task-irrelevant sound stimulation and gated the neural processing of the novel sounds more efficiently than the control group. Furthermore, we replicated our previous finding that, relative to the control group, the musically trained children and adolescents performed faster in standardized tests for inhibition and set shifting. These results provide novel converging behavioral and electrophysiological evidence from a cross-modal paradigm for accelerated maturation of selective attention in musically trained children and adolescents and corroborate the association between musical training and enhanced inhibition and set shifting.Peer reviewe

Auditory event-related potentials

Auditory event related potentials are electric potentials (AERP, AEP) and magnetic fields (AEF) generated by the synchronous activity of large neural populations in the brain, which are time-locked to some actual or expected sound event

Visuomotor Adaptation: Dependency on Motion Trajectory

In order to pick up an object, its visual location must be converted into the appropriate motor commands. Introducing a discrepancy between the seen and felt locations of the object (e.g., via prism goggles) initially impairs the ability to touch it. The sensory system rapidly adapts to the discrepancy, however, returning perception and performance to near normal. Subsequent removal of the discrepancy leads to a renewed performance decrement - a negative aftereect (NAE). It is generally believed that the process of adaptation consists primarily of \recalibrating" the transformation between the visual and proprioceptive perception of spatial location (Bedford, The psychology of learning and motivation, 1999). According to such a purely perceptual account of adaptation, the movement to reach the object is not important. If, however, the transformation from perception to action is altered, then it will be dependent on motion - i.e. changing motion parameters will reduce or eliminate the NAE (see also Martin et al., Brain, 1996). According to our hypothesis spatial visuomotor information is distributively stored and changed by prism adaptation and it is not based on a centrally organized spatial information system. We conducted seven experiments consisting of four blocks each, in which participants had to touch a cross presented at eye level on a touch screen. In the rst block the participants were introduced and familiarized with the experiment. Blocks two and four were pre and post tests to measure the NAE produced during the dierent experimental conditions in block 3 in which the participants were wearing prism goggles: we tested the eects of dierent trajectories, dierent starting points, weight, vertical generalization and dierent types of feedback. A total transfer from an adapted to a non-adapted condition didn't turn up in any of our experiments, although the trajectories where highly identical in some of them. It rather seems that newly learned spatial information in prism adaptation experiments is stored and retrieved distributively for dierent extremities, for dierent trajectories and for dierent stress/strain conditions (e.g. weight). Furthermore, transfer seems to become weaker with bigger dierences in location. Therefore we conclude that no visual \recalibration" is taking place but a relearning of distributetively organized parameters of visuomotor coordination

Prism adaptation: Dependency on motion trajectory

In order to pick up an object, its visual location must be converted into the appropriate motor commands. Introducing a discrepancy between the seen and felt location of the object (e.g., via prism goggles) initially impairs our ability to touch it. The sensory systems rapidly adapt to the discrepancy, however, returning perception and performance to near normal. Subsequent removal of the discrepancy leads to a renewed performance decrement -- a Negative Aftereffect (NAE). It is generally believed that this adaptation consists primarily of “recalibrating” the transformation between the visual and proprioceptive perception of spatial location (Bedford, 1999). According to such a purely perceptual account of adaptation, the exact path used to reach the object should not be important. If, however, it is the transformation from perception to action that is being altered, then changing the motion trajectory should reduce or eliminate the NAE. Starting with both hands on the desktop, the chin resting on a horizontal bar, participants (N=72) had to touch a cross presented at eye level on a touch screen 30 cm in front of them. Four trajectories were possible: reaching to the cross from below or (swinging the arm backwards) from above the bar, using either their left or their right hand. Reaching Accuracy without feedback was determined for all four trajectories before and after adaptation to a single trajectory with prism goggles (19° horizontal displacement). The NAE was 46mm (8.7°) for the adapted trajectory, 26mm negligable for both trajectories of the other hand. The NAE was larger for unfamiliar (above bar, or usage of non-preferred hand) than for familiar trajectories. Visuomotor adaptation is not merely a perceptual recalibration. Not only does the structure of the motion trajectory play a central role, but the familiarity of the trajectory also seems to be important. These results have strong implications for all models of visuomotor adaptation

Visuomotor adaptation: Dependency on motion trajectory

The present contribution studies the rapid adaptation process of the visuomotor system to optical transformations (here: shifting the image horizon-tally via prism goggles). It is generally believed that this adaptation consists primarily of recalibrating the transformation between visual and proprioceptive perception. According to such a purely perceptual account of adaptation, the exact path used to reach the object should not be important. If, however, it is the transformation from perception to action that is being altered, then the adapta-tion should depend on the motion trajectory. In experiments with a variety of different motion trajectories we show that visuomotor adaptation is not merely a perceptual recalibration. The structure of the motion (starting position, trajec-tory, end position) plays a central role, and even the weight load seems to be important. These results have strong implications for all models of visuomotor adaptation