879 research outputs found
Modulation of tactile duration judgments by emotional pictures
Judging the duration of emotional stimuli is known to be influenced by their valence and arousal values. However, whether and how perceiving emotion in one modality affects time perception in another modality is still unclear. To investigate this, we compared the influence of different types of emotional pictures—a picture of threat, disgust, or a neutral picture presented at the start of a trial—on temporal bisection judgments of the duration of a subsequently presented vibrotactile stimulus. We found an overestimation of tactile duration following exposure to pictures of threat, but not pictures of disgust (even though these scored equally high on arousal), in a short-range temporal bisection task (range 300/900 ms). Follow-up experiments revealed that this duration lengthening effect was abolished when the range to be bisected was increased (1000/1900 ms). However, duration overestimation was maintained in the short-range bisection task regardless of whether the interval between the visual and tactile events was short or long. This pattern is inconsistent with a general arousal interpretation of duration distortion and suggests that crossmodal linkages in the processing of emotions and emotional regulation are two main factors underlying the manifestation of crossmodal duration modulation
Positional priming of visual pop-out search is supported by multiple spatial reference frames
The present study investigates the representations(s) underlying positional priming of visual pop-out' search (Maljkodc and Nakayama, 1996). Three search items (one target and two distractors) were presented at different locations, in invariant (Experiment 1) or random (Experiment 2) cross-trial sequences. By these manipulations it was possible to disentangle retinotopic, spatiotopic, and object-centered priming representations. Two forms of priming were tested: target location facilitation (i.e.,faster reaction times - RTswhen the trial n target is presented at a trial n-1 target relative to n-1 blank location) and distractor location inhibition (i.e.,slower RTs for n targets presented at n-1 distractor compared to n-1 blank locations). It was found that target locations were coded in positional short-term memory with reference to both spatiotopic and object-centered representations (Experiment 1 vs. 2). In contrast, distractor locations were maintained in an object-centered reference frame (Experiments 1 and 2). We put forward the idea that the uncertainty induced by the experiment manipulation (predictable versus random cross-trial item displacements) modulates the transition from object- to space-based representations in cross-trial memory for target positions
Drifting perceptual patterns suggest prediction errors fusion rather than hypothesis selection: replicating the rubber-hand illusion on a robot
Humans can experience fake body parts as theirs just by simple visuo-tactile
synchronous stimulation. This body-illusion is accompanied by a drift in the
perception of the real limb towards the fake limb, suggesting an update of body
estimation resulting from stimulation. This work compares body limb drifting
patterns of human participants, in a rubber hand illusion experiment, with the
end-effector estimation displacement of a multisensory robotic arm enabled with
predictive processing perception. Results show similar drifting patterns in
both human and robot experiments, and they also suggest that the perceptual
drift is due to prediction error fusion, rather than hypothesis selection. We
present body inference through prediction error minimization as one single
process that unites predictive coding and causal inference and that it is
responsible for the effects in perception when we are subjected to intermodal
sensory perturbations.Comment: Proceedings of the 2018 IEEE International Conference on Development
and Learning and Epigenetic Robotic
Duration reproduction with sensory feedback delay: differential involvement of perception and action time
Previous research has shown that voluntary action can attract subsequent, delayed feedback events toward the action, and adaptation to the sensorimotor delay can even reverse motor-sensory temporal order judgments. However, whether and how sensorimotor delay affects duration reproduction is still unclear. To investigate this, we injected an onset- or offset-delay to the sensory feedback signal from a duration reproduction task. We compared duration reproductions within (visual, auditory) modality and across audiovisual modalities with feedback signal onset- and offset-delay manipulations. We found that the reproduced duration was lengthened in both visual and auditory feedback signal onset-delay conditions. The lengthening effect was evident immediately, on the first trial with the onset-delay. However, when the onset of the feedback signal was prior to the action, the lengthening effect was diminished. In contrast, a shortening effect was found with feedback signal offset-delay, though the effect was weaker and manifested only in the auditory offset-delay condition. These findings indicate that participants tend to mix the onset of action and the feedback signal more when the feedback is delayed, and they heavily rely on motor-stop signals for the duration reproduction. Furthermore, auditory duration was overestimated compared to visual duration in crossmodal feedback conditions, and the overestimation of auditory duration (or the underestimation of visual duration) was independent of the delay manipulation
The effect of task order predictability in audio-visual dual task performance: just a central capacity limitation?
In classic Psychological-Refractory-Period (PRP) dual-task paradigms, decreasing stimulus onset asynchronies (SOA) between the two tasks typically lead to increasing reaction times (RT) to the second task and, when task order is non-predictable, to prolonged RTs to the first task. Traditionally, both RT effects have been advocated to originate exclusively from the dynamics of a central bottleneck. By focusing on two specific electroencephalographic brain responses directly linkable to perceptual or motor processing stages, respectively, the present study aimed to provide a more detailed picture as to the origin(s) of these behavioral PRP effects. In particular, we employed 2-alternative forced-choice (2AFC) tasks requiring participants to identify the pitch of a tone (high versus low) in the auditory, and the orientation of a target object (vertical versus horizontal) in the visual, task, with task order being either predictable or non-predictable. Our findings show that task order predictability (TOP) and inter-task SOA interactively determine the speed of (visual) perceptual processes (as indexed by the PCN timing) for both the first and the second task. By contrast, motor response execution times (as indexed by the LRP timing) are influenced independently by TOP for the first, and SOA for the second, task. Overall, this set of findings complements classical as well as advanced versions of the central bottleneck model by providing electrophysiological evidence for modulations of both perceptual and motor processing dynamics that, in summation with central capacity limitations, give rise to the behavioral PRP outcome
Thermal Infrared and Optical Photometry of Asteroidal Comet C/2002 CE
C/2002 CE is an object in a retrograde elliptical orbit with Tisserand
parameter indicating a likely origin in the Oort Cloud. It appears to
be a rather inactive comet since no coma and only a very weak tail was detected
during the past perihelion passage. We present multi-color optical photometry,
lightcurve and thermal mid-IR observations of the asteroidal comet.
\textcolor{blue}{ With the photometric analysis in , the surface color is
found to be redder than asteroids, corresponding to cometary nuclei and
TNOs/Centaurs. The time-resolved differential photometry supports a rotation
period of 8.190.05 h. The effective diameter and the geometric albedo are
17.90.9 km and 0.030.01, respectively, indicating a very dark
reflectance of the surface. The dark and redder surface color of C/2002
CE may be attribute to devolatilized material by surface aging suffered
from the irradiation by cosmic rays or from impact by dust particles in the
Oort Cloud. Alternatively, C/2002 CE was formed of very dark refractory
material originally like a rocky planetesimal. In both cases, this object lacks
ices (on the surface at least). The dynamical and known physical
characteristics of C/2002 CE are best compatible with those of the
Damocloids population in the Solar System, that appear to be exhaust cometary
nucleus in Halley-type orbits. The study of physical properties of rocky Oort
cloud objects may give us a key for the formation of the Oort cloud and the
solar system.Comment: 9 pages, 4 figures accepted to Icaru
Mind the Future Gap: Introducing the FOD Framework for Future-Oriented Design
There are many uncertainties and ambiguities in the design of future-oriented artifacts. Societal and environmental developments are unclear; technologies not ready; target users not accessible. Nevertheless, designing future-oriented artifacts provides opportunities to either create radical innovations that present a competitive advantage, or to engage with relevant stakeholders in a speculative way. This paper provides a framework for developing, discussing, and evaluating future-oriented artifacts, which was developed based on literature and conceptual theorizing. It consists of a process model and a morphological box, outlining eight categories of relevance along with several options to choose from. Subsequently, we applied the framework to an existing future design project to illustrate its applicability. The framework spans the space of possible design and evaluation approaches and, hence, provides a guiding schema for researchers and practitioners to discuss the potentials and implications of design concepts for future-oriented artifacts
Designing the Future With the “Delphi Design Sprint”: Introducing a Novel Method for Design Science Research
This paper introduces a novel innovation method that focuses on the development of future-oriented artifacts. The “Delphi Design Sprint” combines two existing methods—the Delphi method and Design Sprints. The development of the method follows an action research approach and was tested and validated in a university-led design project involving a panel of 20 international experts. This paper introduces the method and describes exemplary results of the project’s outcome
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