![]() In contrast, low-level theories explain forward displacements with mechanisms that occur at the perceptual level. The crucial role of higher cognitive mechanisms in the emergence of the representational momentum effect has been supported by the findings of an fMRI study that revealed the involvement of prefrontal areas (Rao et al., 2004). That is, when a moving object vanishes abruptly, the predicted course of target motion is beyond the actual position of the trajectory’s termination point, resulting in mislocalization farther in the direction of motion. More recent studies have discussed the observed forward displacement in terms of the concept of mental extrapolation of the trajectory at higher cognitive levels (Hubbard, 2005 Hubbard & Bharucha, 1988 Taya & Miura, 2010). The physical-momentum hypothesis states that a moving object cannot halt immediately, and therefore the representation of perceived motion is briefly sustained following motion offset. At cognitive levels, the effect was initially explained by internalized principles of physical rules (Freyd, 1987). Several theories considering low-level sensory processes, higher-level cognitive processes, and network models were critically examined by Hubbard ( 2010). To date, the underlying mechanisms of representational momentum are still a matter of debate. Together, these findings indicate that the modality-specific processing of motion parameters affects the extrapolation of the trajectory. Displacements in the visual task were dependent on velocity and the spatial location of the final position, but an additional influence of motion direction was observed in the auditory tasks. Furthermore, our results revealed clear differences between visual and auditory tasks. In all three experiments, less precise encoding of spatial coordinates in paralateral space resulted in larger forward displacements, but this effect was drowned out by the underestimation of target eccentricity in the extreme periphery. To assess whether auditory performance is affected by dynamically changing binaural cues that are used for the localization of moving auditory stimuli (interaural time differences for low-frequency sounds and interaural intensity differences for high-frequency sounds), two distinct noise bands were employed in Experiments 1 and 2. As such, the purpose of the present free-field study was to investigate the influences of the spatial location of motion offset, stimulus velocity, and motion direction on the localization of the final positions of moving auditory stimuli (Experiment 1 and 2) and moving visual stimuli (Experiment 3). However, actual comparisons of the magnitudes of displacement between visual tasks and auditory tasks using the same experimental setup are rare. All rights reserved.Similarities have been observed in the localization of the final position of moving visual and moving auditory stimuli: Perceived endpoints that are judged to be farther in the direction of motion in both modalities likely reflect extrapolation of the trajectory, mediated by predictive mechanisms at higher cognitive levels. BAHA implantation is a reliable, safe and efficient therapeutic option that allows a significantly better audiologic outcome when compared to unaided EACR for patients with CAA.Ĭopyright © 2011 Elsevier Ireland Ltd. It can however, when combined to conventional air conduction hearing aids, provide excellent audiologic outcomes comparable to BAHA. HG does not seem to be influenced by the presence of microtia.ĮACR, although constituting an attractive option, does not give acceptable results alone. ![]() BAHA group compared postoperatively to EACR group showed significantly a superior HG of 46.9 ± 7.0 dB (p0.05) was found between patient's Jahrsdoerfer's score and their audiologic outcome. Preoperative AC were significantly different between groups, at 500, 10 Hz but not at 4000 Hz. ![]() EACR patients were graded retrospectively upon Jahrsdoerfer's classification. Operative time, complications and associated microtia were documented as well. Air conduction (AC), bone conduction (BC), pure tone average (PTA) and speech discrimination score (SDS) were compared preoperatively, and hearing gain (HG) postoperatively at 6 and at 12 months at frequencies of 500, 1000, 20 Hz. 20 patients underwent EACR, whereas another 20 patients were implanted with a BAHA device. To compare the audiologic outcome and feasibility of bone-anchored hearing aid (BAHA) and external auditory canal reconstruction (EACR) surgeries in pediatric patients presenting a congenital aural atresia (CAA).Ī retrospective chart review of 40 patients operated in our tertiary pediatric care center between 20 was performed.
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