Capturing the dynamics of peripersonal space by integrating expectancy effects and sound propagation properties

AbstractHighlightsLogarithmically distributed auditory distances provides an apt granularity of PPSMeasuring expectation helps to interpret behavioral impact of audiotactile integrationTactile RTs follows a logarithmic decrease due to audiotactile integrationPeripersonal space is better characterized and quantified with this refinementBackgroundHumans perceive near space and far space differently. Peripersonal space, i.e. the space directly surrounding the body, is often studied using paradigms based on auditory-tactile integration. In these paradigms, reaction time to a tactile stimulus is measured in the presence of a concurrent auditory looming stimulus.New MethodWe propose here to refine the experimental procedure considering sound propagation properties in order to improve granularity and relevance of auditory-tactile integration measures. We used a logarithmic distribution of distances for this purpose. We also want to disentangle behavioral contributions of the targeted audiotactile integration mechanisms from expectancy effects. To this aim, we added to the protocol a baseline with a fixed sound distance.ResultsExpectation contributed significantly to overall behavioral responses. Subtracting it isolated the audiotactile effect due to the stimulus proximity. This revealed that audiotactile integration effects have to be tested on a logarithmic scale of distances, and that they follow a linear variation on this scale.Comparison with Existing Method(s)The granularity of the current method is more relevant, providing higher spatial resolution in the vicinity of the body. Furthermore, most of the existing methods propose a sigmoid fitting, which rests on the intuitive framework that PPS is an in-or-out zone. Our results suggest that behavioral effects follow a logarithmic decrease, thus a response graduated in space.ConclusionsThe proposed protocol design and method of analysis contribute to refine the experimental investigation of the factors influencing and modifying multisensory integration phenomena in the space surrounding the body.

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Reliable Acoustic Path and Direct-Arrival Zone Spatial Gain Analysis for a Vertical Line Array

Sensors ◽

10.3390/s18103462 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3462 ◽

Cited By ~ 1

Author(s):

Chunyu Qiu ◽

Shuqing Ma ◽

Yu Chen ◽

Zhou Meng ◽

Jianfei Wang

Keyword(s):

Sound Propagation ◽

Correlation Coefficients ◽

Deep Ocean ◽

Vertical Line ◽

Horizontal Line ◽

Acoustic Path ◽

Vertical Arrays ◽

Peak Structure ◽

Line Array ◽

Propagation Properties

A method is developed in this paper to calculate the spatial gain of a vertical line array when the plane-wave assumption is not applicable and when the oceanic ambient noise is correlated. The proposed optimal array gain (OAG), which can evaluate the array’s performance and effectively guide its deployment, can be given by an equation in which the noise gain (NG) is subtracted from the signal gain (SG); hence, a high SG and a negative NG can enhance the performance of the array. OAGs and SGs with different array locations are simulated and analyzed based on the sound propagation properties of the direct-arrival zone (DAZ) and the reliable acoustic path (RAP) using ray theory. SG and NG are related to the correlation coefficients of the signals and noise, respectively, and the vertical correlation is determined by the structures of the multipath arrivals. The SG in the DAZ is always high because there is little difference between the multipath waves, while the SG in the RAP changes with the source-receiver range because of the variety of structure in the multiple arrivals. The SG under different conditions is simulated in this work. The “dual peak” structure can often be observed in the vertical directionality pattern of the noise because of the presence of bottom reflection and deep sound channel. When the directions of the signal and noise are close, the conventional beamformer will enhance the correlation of not only the signals but also the noise; thus, the directivity of the signals and noise are analyzed. Under the condition of having a typical sound speed profile, the OAG in some areas of the DAZ and RAP can achieve high values and even exceed the ideal gain of horizontal line array 10 logN dB, while, in some other areas, it will be lowered because of the influence of the NG. The proposed method of gain analysis can provide analysis methods for vertical arrays in the deep ocean under many conditions with references. The theory and simulation are tested by experimental data.

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ULTRASONIC PROPAGATION IN SOLENHOFEN LIMESTONE AT HIGH PRESSURES

Geophysics ◽

10.1190/1.1440863 ◽

1978 ◽

Vol 43 (5) ◽

pp. 1014-1017

Author(s):

I. J. Fritz

Keyword(s):

High Pressure ◽

Wave Propagation ◽

Phase Transitions ◽

Seismic Waves ◽

High Pressures ◽

Sound Propagation ◽

Wave Measurements ◽

Ultrasonic Propagation ◽

Propagation Properties ◽

The Relationship

The measurement of ultrasonic velocities at high pressure in minerals and rocks provides information pertinent to a variety of geophysical and engineering problems such as those of determining the state of matter in the earth's interior, understanding the propagation of seismic waves, and characterizing mechanical behavior of materials that are important in mining technology. In recent years there have been a number of reported high pressure sound velocity measurements in various kinds of limestone. (A concise review of this work can be found in a recent paper by Singh and Kennedy, 1974.) Such measurements continue to be of interest because of the relationship to shock‐wave propagation properties (Grady et al, 1977). From the previous measurements it has been found that the phase transitions in calcite, which is the main constituent of limestone, strongly influence the sound velocities. The phase transitions in pure calcite occur at 14.5 kbar (calcite I–II) and 17.4 kbar (calcite II–III) (Singh and Kennedy, 1974); however, because the transitions may be shifted in pressure and spread out over a range of pressures in a rock, it is necessary to make measurements to pressures in excess of 20 kbar in order to characterize the effects of the transitions. To date there has been only one experimental study of the effect of the II–III transition on sound propagation, namely the longitudinal wave measurements in Oak Hall limestone made by Wang and Meltzer (1973). In order to further characterize the effect of the II–III transition on sound propagation in limestone, we have made measurements to 25 kbar on Solenhofen limestone. We were able to measure both longitudinal and transverse velocities over the full pressure range; thus, our measurements represent the first study of the effect of the II–III transition on shear wave propagation under conditions of hydro static pressure.

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Evaluating the effect of seismic surveys on fish — the efficacy of different exposure metrics to explain disturbance

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2012-0465 ◽

2013 ◽

Vol 70 (9) ◽

pp. 1271-1277 ◽

Cited By ~ 5

Author(s):

Nils Olav Handegard ◽

Tron Vedul Tronstad ◽

Jens Martin Hovem

Keyword(s):

Sound Propagation ◽

Bottom Topography ◽

Geometrical Model ◽

Propagation Model ◽

Sound Exposure ◽

Disturbance Effects ◽

Air Gun ◽

Complex Propagation ◽

Propagation Properties ◽

Exposure Metrics

To assess potential disturbance effects on fish from seismic air-gun surveys, we described several metrics to characterize the exposures from such surveys, including the number of emissions by area and time, and metrics based on accumulated sound exposure levels (SEL). For the SEL-based metrics we used both a simple spherical–geometrical model and a model that incorporated physical sound propagation properties such as bottom topography and the vertical difference in sound speed. We applied the metrics to two experiments in Norwegian waters (the Nordkappbanken and Vesterålen experiments) where fish distributions and fisheries were affected by the air-guns, but where the disturbance was stronger in the Nordkappbanken case. The metrics based on the number of emissions by area and time showed a stronger impact in the Nordkappbanken case. For the SEL-based metrics, the simple sound propagation model failed because of artificially elevated levels close to the emissions, but for the more complex propagation model, contrary to expectations, a stronger SEL was found in the Vesterålen case. We conclude that simple sound propagation models should be avoided and that the reliance on sound energy metrics like SEL for disturbance effects must be interpreted with caution.

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Sound Propagation Properties of the Discrete-Velocity Boltzmann Equation

Communications in Computational Physics ◽

10.4208/cicp.271011.020212s ◽

2013 ◽

Vol 13 (3) ◽

pp. 671-684 ◽

Cited By ~ 5

Author(s):

Erlend Magnus Viggen

Keyword(s):

Boltzmann Equation ◽

Sound Propagation ◽

Navier Stokes ◽

Sound Waves ◽

Discrete Velocity ◽

Numerical Resolution ◽

Discretisation Error ◽

Order Of Magnitude ◽

Plane Sound ◽

Propagation Properties

AbstractAs the numerical resolution is increased and the discretisation error decreases, the lattice Boltzmann method tends towards the discrete-velocity Boltzmann equation (DVBE). An expression for the propagation properties of plane sound waves is found for this equation. This expression is compared to similar ones from the Navier-Stokes and Burnett models, and is found to be closest to the latter. The anisotropy of sound propagation with the DVBE is examined using a two-dimensional velocity set. It is found that both the anisotropy and the deviation between the models is negligible if the Knudsen number is less than 1 by at least an order of magnitude.

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A Scaling Method for Modal Sound Propagation in Annular Ducts

Volume 2B: Turbomachinery ◽

10.1115/gt2015-42839 ◽

2015 ◽

Author(s):

C. Mandanna Hurfar ◽

Michael Bartelt ◽

Joerg R. Seume

Keyword(s):

Mach Number ◽

Sound Propagation ◽

Axial Flow ◽

Experimental Investigations ◽

Axial Component ◽

Aircraft Engines ◽

Noise Emission ◽

Scaling Method ◽

Propagation Properties ◽

Modal Group

The interaction between stationary and rotating components is a major source of the noise emission of aircraft engines. Within the engine, the generated sound propagates in discrete pressure patterns, so-called spinning modes. In order to develop noise reduction technologies for these acoustic components, numerical as well as experimental investigations are carried out. In many cases however, the test rigs are geometrically and thermodynamically scaled in comparison to the turbomachines used in aircraft engines. The objective of this paper is to provide an analytical method to investigate the effect of scaling on the major properties of modal sound propagation in symmetric hard-walled annular ducts with a superimposed uniform axial flow. The potential of generating similar sound propagation properties in two ducts is assessed. For these purposes, the magnitude of the dominating modal group velocity vector, the corresponding axial component, and the angle relative to the duct axis are expressed in terms of the dimensionless parameters Mach number, Helmholtz number, and hub-to-tip ratio. In addition, the corresponding quantities of the wave vector are considered. With respect to these properties, it is shown that for a constant hub-to-tip ratio, modal sound propagation in two annular ducts is similar if the Mach number and Helmholtz number are identical.

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Sound Propagation through the Stochastic Ocean

10.1017/cbo9781139680417 ◽

2015 ◽

Cited By ~ 3

Author(s):

John A. Colosi

Keyword(s):

Sound Propagation

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Individual Differences in the Flexibility of Peripersonal Space

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000350 ◽

2017 ◽

Vol 64 (1) ◽

pp. 49-55 ◽

Cited By ~ 14

Author(s):

Samuel B. Hunley ◽

Arwen M. Marker ◽

Stella F. Lourenco

Keyword(s):

Individual Differences ◽

Peripersonal Space ◽

The Body ◽

Laser Pointer ◽

Baseline Measure ◽

Bisection Task ◽

Defensive Function ◽

Representational Space ◽

Laser Condition ◽

Line Bisection Task

Abstract. The current study investigated individual differences in the flexibility of peripersonal space (i.e., representational space near the body), specifically in relation to trait claustrophobic fear (i.e., fear of suffocating or being physically restricted). Participants completed a line bisection task with either a laser pointer (Laser condition), allowing for a baseline measure of the size of one’s peripersonal space, or a stick (Stick condition), which produces expansion of one’s peripersonal space. Our results revealed that individuals high in claustrophobic fear had larger peripersonal spaces than those lower in claustrophobic fear, replicating previous research. We also found that, whereas individuals low in claustrophobic fear demonstrated the expected expansion of peripersonal space in the Stick condition, individuals high in claustrophobic fear showed less expansion, suggesting decreased flexibility. We discuss these findings in relation to the defensive function of peripersonal space and reduced attentional flexibility associated with trait anxieties.

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