610 research outputs found
The multisensory body revealed through its cast shadows
One key issue when conceiving the body as a multisensory object is how the cognitive
system integrates visible instances of the self and other bodies with one\u2019s own
somatosensory processing, to achieve self-recognition and body ownership. Recent
research has strongly suggested that shadows cast by our own body have a special
status for cognitive processing, directing attention to the body in a fast and highly specific
manner. The aim of the present article is to review the most recent scientific contributions
addressing how body shadows affect both sensory/perceptual and attentional processes.
The review examines three main points: (1) body shadows as a special window to
investigate the construction of multisensory body perception; (2) experimental paradigms
and related findings; (3) open questions and future trajectories. The reviewed literature
suggests that shadows cast by one\u2019s own body promote binding between personal
and extrapersonal space and elicit automatic orienting of attention toward the bodypart
casting the shadow. Future research should address whether the effects exerted
by body shadows are similar to those observed when observers are exposed to other
visual instances of their body. The results will further clarify the processes underlying the
merging of vision and somatosensation when creating body representations
Open Cluster Characterization via Cross-Correlation with Spectral Library
We present a characterization method based on spectral cross-correlation to
obtain the physical parameters of the controversial stellar aggregate
ESO442-SC04. The data used was obtained with GMOS at Gemini-South telescope
including 17 stars in the central region of the ob ject and 6 standard-stars.
FXCOR was used in an iterative process to obtain self-consistent radial
velocities for the standard-stars and averaged radial velocities for the
science spectra. Spectral types, effective temperature, suface gravity and
metallicities parameters were determined using FXCOR to correlate cluster
spectra with ELODIE spectral library and selecting the best correlation matches
using the Tonry and Davis Ratio (TDR). Analysis of the results suggests that
the stars in ESO442-SC04 are not bound and therefore they do not constitute a
physical system.Comment: 4-page paper from IAU symposium 266. Contains 3 eps figures and IAU
document class file 'iau.cls
Training spatial hearing skills in virtual reality through a sound-reaching task
Sound localization is crucial for interacting with the surrounding world. This ability can be learned across time and improved by multisensory and motor cues. In the last decade, studying the contributions of multisensory and motor cues has been facilitated by the increased adoption of virtual reality (VR). In a recent study, sound localization had been trained through a task where the visual stimuli were rendered through a VR headset, and the auditory ones through a loudspeaker moved around by the experimenter. Physically reaching to sound sources reduced sound localization errors faster and to a greater extent if compared to naming sources’ positions. Interestingly, training efficacy extended also to hearing-impaired people. Yet, this approach is unfeasible for rehabilitation at home. Fullyvirtual approaches have been used to study spatial hearing learning processes, performing headphones-rendered acoustic simulations. In the present study, we investigate whether the effects of our reaching-based training can be observed when taking advantage of such simulations, showing that the improvement is comparable between the full-VR and blended VR conditions. This validates the use of training paradigms that are completely based on portable equipment and don’t require an external operator, opening new perspectives in the field of remote rehabilitation
Peculiar spline collocation method for solving rough and stiff delay differential problems
As well known, solutions of delay differential equations (DDEs) are characterized by low regularity. In particular solutions of neutral delay differential equations (NDDEs) frequently exhibit discontinuities in the first derivative so that the differential problems become rough. The aim of this paper is to approximate the solutions of such rough delay differential problems by means of a peculiar deficient spline collocation method. Significant numerical examples are provided to enlighten the features of the proposed method
The plasticity of near space: evidence for contraction
The distinction between near space and the space farther away has been well established, as has the relation of this distinction to arm length. Recent studies provide evidence for the plasticity of near space, showing that it is possible to expand its extent ("size") through tool-use. In the present study, we examine the converse effect, whether contraction of near space results from increasing the effort involved on a line bisection task. Adult participants bisected lines at different distances, while, in some cases, wearing weights. In Experiment 1, the arms, specifically, were weighted (wrist weights), and in Experiment 2, more general body weights were used (heavy backpack). As in previous studies, unencumbered participants showed leftward bias when bisecting lines at the closest distances and a rightward shift in bias with increasingly farther distances. With wrist weights, but not a heavy backpack, participants showed more rightward bias at the closest distances, and a more gradual rightward shift with increasing distance, as if the nearest locations were represented as being farther away. These results suggest that increased effort, when specifically related to the arm, can serve to reduce the size of near space, providing support for the generally symmetrical plasticity of near space representations
UBVI CCD photometry and star counts in 9 inner disk Galactic star clusters
We present and discuss new CCD-based photometric material in the UBVI
pass-bands for nine Galactic star clusters located inside the solar ring, for
which no CCD data are currently available. They are: IC 2714, NGC 4052,
ESO131SC09, NGC 5284, NGC 5316, NGC 5715, VdB-Hagen ~164, NGC 6268, and Czernik
38. We first perform star counts by combining our optical photometry wi th
2MASS, and derive cluster sizes and radial density profiles. The fundamental
parameters - age, reddening and distance- are then inferred from the analysis
of the star distribution in color-color and color-magnitude diagrams of only
the spatially selected likely members. Our analysis shows that ESO131SC09, NGC
5284, and VdB-Hagen 164 are most probably not clusters, but random enhancements
of a few bright stars along the line of sight, with prop erties much similar to
open cluster remnants. The remaining clusters are physical groups, and are all
younger than about 1 Gyr . We use the newly derived set of parameters, in
particular distance and reddening, to investigate their position in the Galaxy
in the context of the spiral structure of the Milky Way. We find that the
youngest clusters (IC 2714, NGC 5316, and NGC 6268) are located close to or
inside the Carina-Sagittarius arm, and are therefore {\i t bona fide} spiral
structure tracers. On the other hand, the oldest (Czernik 38, NGC 4052, and NGC
5715) are floating in the inter-arm space between the Carina-Sagittarius and
the more distant Scutum-Crux arm. Interestingly enough, the oldest clusters of
this sample - Czernik 38 and NGC 5715- are among the few known open clusters to
be older or as old as the Hyades in the inner Galactic disk, where star
clusters are not expected to survive for a long time, because of the strong
tidal field and the higher probability of close encounters .Comment: 17 pages, 11 eps figures, in press in MNRA
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