Directional Sensitivity of Microphonic Potentials Form the Perch Ear

1. Microphonic potentials were recorded from the lagena and from different parts of the sacculus in the perch during horizontal and vertical vibration of the fish in air. This stimulation technique gives a good simulation of sound stimulation in water. 2. The lagena was predominantly sensitive to vertical vibrations, whereas the anterior part of the sacculus was equally sensitive to vertical and horizontal vibrations. A gradient is seen along the sacculus, in that the more posterior positions show a tendency towards greater relative vertical sensitivity. By comparing the nervous output from the lagena and from the sacculus the fish might thus get information about the vertical direction of the sound source. 3. The amplitude of the saccular microphonic potentials evoked by horizontal vibrations was a function of the vibration direction. Maximal responses were obtained when this direction deviated about 20° from the long axis of the fish, which is approximately parallel to the long axis of the sacculi. The difference in response between the two ears might be utilized to give directional information about the horizontal position of the sound source. 4. Sound-induced pulsations radiating from the swimbladder will be efficient in evoking saccular microphonic potentials. This causes masking of the difference in response between the two ears, but directional information may still be obtained. It is proposed that the power of angle separation in the horizontal plane should be optimal for sound waves side on to the fish, and that a fish possessing a swimbladder may be able to detect the sound direction with higher accuracy in the vertical than in the horizontal plane. 5. The relative effect in evoking microphonic potentials of vertical compared to horizontal vibrations was frequency dependent, and it is concluded that the pattern of otolith movements during sound stimulation may also change with frequency. This phenomenon constitutes a possible basis for peripheral frequency analysis in fish.

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Directional Sensitivity of Saccular Microphonic Potentials in the Haddock

Journal of Experimental Biology ◽

10.1242/jeb.59.2.425 ◽

1973 ◽

Vol 59 (2) ◽

pp. 425-433 ◽

Cited By ~ 1

Author(s):

P. S. ENGER ◽

A. D. HAWKINS ◽

O. SAND ◽

C. J. CHAPMAN

Keyword(s):

Sound Source ◽

Sensory Cells ◽

Directional Sensitivity ◽

Sound Stimulation ◽

Vibration Direction ◽

Horizontal Vibration ◽

Implanted Electrodes ◽

Maximal Sensitivity ◽

Sound Reception

1. Microphonic potentials from the sacculus in the haddock have been recorded by implanted electrodes during horizontal vibration of the fish in air. This gives a good simulation of sound stimulation in water. 2. The microphonic potential amplitude was a function of the vibration angle, and from most recording loci maximal amplitudes were obtained for vibration directions parallel to the long axis of the fish. The sensory cells contributing to this response are therefore most sensitive to displacements in the same direction as sound-induced swimbladder pulsations would produce. This result thus supports the theory of an accessory role of the swimbladder in sound reception. 3. Highest sensitivity to vibration directions other than parallel to the long axis of the fish has been obtained from other recording loci. One example of highest sensitivity to a vibration direction at right angle to the long axis of the fish is presented. 4. The findings that different sensory cells appear to have different axes of maximal sensitivity to vibration provides one possible neurological explanation for the ability of fish to detect the direction to a sound source.

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Directional Hearing in the Japanese Quail (Coturnix Coturnix Japonica): II. Cochlear Physiology

Journal of Experimental Biology ◽

10.1242/jeb.86.1.153 ◽

1980 ◽

Vol 86 (1) ◽

pp. 153-170

Author(s):

R. B. COLES ◽

D. B. LEWIS ◽

K. G. HILL ◽

M. E. HUTCHINGS ◽

D. M. GOWER

Keyword(s):

Pressure Gradient ◽

Free Field ◽

Directional Hearing ◽

Directional Sensitivity ◽

Ear Canal ◽

Directional Information ◽

Cochlear Physiology ◽

Directivity Patterns ◽

The Difference ◽

Sound Diffraction

The directional sensitivity of cochlear microphonics (CM) was studied inthe quail by rotating a free-field sound source (pure tones, 160-10 kHz)through 360° in the horizontal plane, under anechoic conditions. Sound diffraction by the head was monitored simultaneously by a microphone at the entrance to the ipsilateral (recorded) ear canal. Pressure-field fluctuations measured by the microphone were non-directional (≤ 4 dB) up to 4 kHz; the maximum head shadow was 8 dB at 6.3 kHz. In comparison, the CM sensitivity under went directional fluctuations ranging up to 25 dB for certain low, mid and high frequency band widths. There was noticeable variation between quail for frequencies producing maximum directional effects, although consistently poor directionality was seen near 820 Hz andto a lesser extent near 3.5 kHz. Well-defined CM directivity patterns reflected the presence of nulls (insensitive regions) at critical positions around the head and the number of nulls increased with frequency. Five major types of directivity patterns were defined using polar co-ordinates: cardioid, supercardioid, figure-of-eight, tripartite and multilobed. Such patterns were largely unrelated to head shadow effects. Blocking the ear canal contralateral to there corded ear was shown to effectively abolish CM directionality, largely by eliminating regions of insensitivity to sound. It is inferred that the quail ear functions as an asym metrical pressure gradient receiver, the pressure gradient function being mediated by the interauralcavity. It is proposed that the central auditory system codes directional information by a null detecting method and computes an unambiguous (i.e.intensity independent) directional cue. This spatial cue is achieved by the difference between the directional sensitivities of the two ears, defined as the Directional Index (DI). The spatial distribution of DI values (difference pattern) demonstrated ranges and peaks which closely reflected the extent and position of nulls determined from monaural directivity functions. Large directional cues (up to 25 dB) extended throughout most of the audible spectrum of the quail and the sharpness of difference patterns increased with frequency. Primary ‘best’ directions, estimated from peaks in difference patterns, tended to move towards the front of the head at higher frequencies; rearward secondary peaks also occurred. From the properties of directional cues it is suggested that the ability of birds to localize sound need not necessarily depend on frequency; however, spatial acuity may be both frequency and direction dependent, and include the possibility of front-torearerrors. The directional properties of bird vocalizations may need to bere assessed on the basis of the proposed mechanism for directional hearing.

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Brain Neurones Involved in the Control of Walking in the Cricket Gryllus Bimaculatus

Journal of Experimental Biology ◽

10.1242/jeb.166.1.113 ◽

1992 ◽

Vol 166 (1) ◽

pp. 113-130 ◽

Cited By ~ 4

Author(s):

HARTMUT BÖHM ◽

KLAUS SCHILDBERGER

Keyword(s):

Sound Source ◽

Discharge Rate ◽

Spike Rate ◽

Directional Sensitivity ◽

Stimulus Situation ◽

Gryllus Bimaculatus ◽

Directional Information ◽

Level Of Activity ◽

The Mean ◽

And Control

The responses of single brain neurones to artificial calling song, to moving striped patterns and to air puffs were recorded while tethered crickets were walking on a sphere in such a way that their intended orientation to the stimuli could be measured. Local and descending brain neurones responsive to only one of the stimuli tested often encoded the directional information contained in the stimulus (e.g. the direction of the sound source or the direction of stripe movement). Brain neurones with little directional sensitivity responded with marked habituation to all stimuli, so that their responses primarily signalled changes in the overall stimulus situation. The responses of some neurones were stronger during walking than when the cricket was standing still. In the case of one descending neurone, which increased its level of activity shortly before and during the walking phases, the mean spike rate was correlated with the forward velocity. By altering the discharge rate of another descending neurone, it was possible to elicit walking in the manner typical of crickets. Maintenance and control of walking by such ‘command neurones’ is discussed.

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Dielectric anisotropy as indicator of crystal orientation fabric in Dome Fuji ice core: method and initial results

Journal of Glaciology ◽

10.1017/jog.2021.73 ◽

2021 ◽

pp. 1-12

Author(s):

Tomotaka Saruya ◽

Shuji Fujita ◽

Ryo Inoue

Keyword(s):

Crystal Orientation ◽

Horizontal Plane ◽

Ice Core ◽

Vertical Plane ◽

Vertical Direction ◽

Core Sample ◽

Dielectric Anisotropy ◽

Principal Axes ◽

Polycrystalline Ice ◽

Initial Results

Abstract Polycrystalline ice is known to exhibit macroscopic anisotropy in relative permittivity (ɛ) depending on the crystal orientation fabric (COF). Using a new system designed to measure the tensorial components of ɛ, we investigated the dielectric anisotropy (Δɛ) of a deep ice core sample obtained from Dome Fuji, East Antarctica. This technique permits the continuous nondestructive assessment of the COF in thick ice sections. Measurements of vertical prism sections along the core showed that the Δɛ values in the vertical direction increased with increasing depth, supporting previous findings of c-axis clustering around the vertical direction. Analyses of horizontal disk sections demonstrated that the magnitude of Δɛ in the horizontal plane was 10–15% of that in the vertical plane. In addition, the directions of the principal axes of tensorial ɛ in the horizontal plane corresponded to the long or short axis of the elliptically elongated single-pole maximum COF. The data confirmed that Δɛ in the vertical and horizontal planes adequately indicated the preferred orientations of the c-axes, and that Δɛ can be considered to represent a direct substitute for the normalized COF eigenvalues. This new method could be extremely useful as a means of investigating continuous and depth-dependent variations in COF.

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Horizontal versus vertical charge and energy transfer in hybrid assemblies of semiconductor nanoparticles

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.3.72 ◽

2012 ◽

Vol 3 ◽

pp. 629-636 ◽

Cited By ~ 7

Author(s):

Gilad Gotesman ◽

Rahamim Guliamov ◽

Ron Naaman

Keyword(s):

Energy Transfer ◽

Charge Transfer ◽

Horizontal Plane ◽

Quartz Substrate ◽

Vertical Direction ◽

Time Resolved ◽

Transfer Processes ◽

Donor And Acceptor ◽

Hybrid Assemblies ◽

Time Resolved Photoluminescence

We studied the photoluminescence and time-resolved photoluminescence from self-assembled bilayers of donor and acceptor nanoparticles (NPs) adsorbed on a quartz substrate through organic linkers. Charge and energy transfer processes within the assemblies were investigated as a function of the length of the dithiolated linker (DT) between the donors and acceptors. We found an unusual linker-length-dependency in the emission of the donors. This dependency may be explained by charge and energy transfer processes in the vertical direction (from the donors to the acceptors) that depend strongly on charge transfer processes occurring in the horizontal plane (within the monolayer of the acceptor), namely, parallel to the substrate.

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ENGINEERING OF ACOUSTIC TECHNOLOGY FOR UNDERWATER POSITIONING OBJECT

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.29244/jitkt.v10i3.21456 ◽

2018 ◽

Vol 10 (3) ◽

pp. 629-637

Author(s):

Billi Rifa Kusumah ◽

Indra Jaya ◽

Henry M. Manik ◽

. Susilohadi

Keyword(s):

Control System ◽

Sound Source ◽

Arrival Time ◽

Equation Model ◽

Control Device ◽

Electromagnetic Signal ◽

Positioning System ◽

Underwater Sound ◽

Underwater Positioning ◽

The Difference

Underwater Positioning System (UPS) is a system to track the existence of the position of an object by utilizing the arrival time of the signal measurement. On land, the system uses an electromagnetic signal called GPS. However, because it cannot penetrate water effectively, an acoustic signal is used as an alternative. The purpose of this research is to engineer the control system of data acquisition and underwater acoustic device to measure arrival time (TOA) and apply equation model for underwater sound source positioning system. the effective frequency resonance of the transducer and the hydrophone is at a frequency of 6 kHz. The acquisition control device is able to measure the TOA signal with an error on a digital channel smaller than an analog channel. The difference between the TOA values measured by oscilloscope and acquisition control system is caused by inaccuracy of threshold estimates at the receiver's peak detector circuit. The position of the sound source coordinates obtained from the equation model shows the highest difference in depth point (z) compared to points (x) and (y), caused by the equation model used is limited to four hydrophone units forming a horizontal baseline.

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3D PETROPHYSICS FOR HAWE: CASE STUDIES

10.30632/spwla-2021-0055 ◽

2021 ◽

Author(s):

Alexander Kolomytsev ◽

◽

Yulia Pronyaeva Pronyaeva ◽

Keyword(s):

Case Studies ◽

Seismic Data ◽

Reservoir Characterization ◽

Vertical Direction ◽

Geological Structure ◽

Current Layer ◽

Radial Model ◽

The Difference ◽

Geological Concept ◽

Property Changes

Most conventional log interpretation technics use the radial model, which was developed for vertical wells and work well in them. But applying this model to horizontal wells can result in false conclusions. The reasons for this are property changes in vertical direction and different depth of investigation (DOI) of logging tools. DOI area probably can include a response from different layers with different properties. All of this complicates petrophysical modeling. The 3D approach for high angle well evaluation (HAWE) is forward modeling in 3D. For this modeling, it is necessary to identify the geological concept near the horizontal well section using multiscale data. The accuracy of modeling depends on the details of the accepted geological model based on the data of borehole images, logs, geosteering inversion, and seismic data. 3D modeling can be applied to improve the accuracy of reservoir characterization, well placement, and completion. The radial model is often useless for HAWE because LWD tools have different DOI and the invasion zone was not formed. But the difference between volumetric and azimuthal measurements is important for comprehensive interpretation because various formations have different properties in vertical directions. Resistivity tools have the biggest DOI. It is important to understand and be able to determine the reason for changes in log response: a change in the properties of the current layer or approaching the layers with other properties. For this, it is necessary to know the distance to the boundaries of formations with various properties and, therefore, to understand the geological structure of the discovered deposits, and such information on the scale of well logs can be obtained either by modeling or by using extra deep resistivity inversion (mapping). The largest amount of multidisciplinary information is needed for modeling purposes - from images and logs to mapping and seismic data. Case studies include successful examples from Western Siberia clastic formations. In frame of the cases, different tasks have been solved: developed geological concept, updated petrophysical properties for STOIIP and completion, and provided solutions during geosteering. Multiscale modeling, which includes seismic, geosteering mapping data, LWD, and imagers, has been used for all cases.

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Effects of low‐frequency thresholds on sound‐source identification in the frontal horizontal plane using interaural time difference cues

The Journal of the Acoustical Society of America ◽

10.1121/1.424906 ◽

1999 ◽

Vol 105 (2) ◽

pp. 1025-1025

Author(s):

Stuart Gatehouse ◽

Catherine Lever ◽

Christian Lorenzi ◽

Patrick Howell

Keyword(s):

Sound Source ◽

Source Identification ◽

Horizontal Plane ◽

Interaural Time Difference ◽

Low Frequency ◽

Time Difference ◽

Sound Source Identification

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Directional Sensitivity of Neurons in the Primary Auditory (AI) Cortex: Effects of Sound-Source Intensity Level

Journal of Neurophysiology ◽

10.1152/jn.00563.2002 ◽

2003 ◽

Vol 89 (2) ◽

pp. 1024-1038 ◽

Cited By ~ 20

Author(s):

Richard A. Reale ◽

Rick L. Jenison ◽

John F. Brugge

Keyword(s):

Receptive Field ◽

Sound Source ◽

Response Latency ◽

Primary Auditory Cortex ◽

Directional Sensitivity ◽

Spherical Harmonic Analysis ◽

Intensity Level ◽

Inverse Gaussian ◽

Operating Characteristics ◽

Gaussian Density

Transient sounds were delivered from different directions in virtual acoustic space while recording from single neurons in primary auditory cortex (AI) of cats under general anesthesia. The intensity level of the sound source was varied parametrically to determine the operating characteristics of the spatial receptive field. The spatial receptive field was constructed from the onset latency of the response to a sound at each sampled direction. Spatial gradients of response latency composing a receptive field are due partially to a systematic co-dependence on sound-source direction and intensity level. Typically, at any given intensity level, the distribution of response latency within the receptive field was unimodal with a range of approximately 3–4 ms, although for some cells and some levels, the spread could be as much as 20 or as little as 2 ms. Response latency, averaged across directions, differed among neurons for the same intensity level, and also differed among intensity levels for the same neuron. Generally, increases in intensity level resulted in decreases in the mean and variance, which follows an inverse Gaussian distribution. Receptive field models, based on response latency, are developed using multiple parameters (azimuth, elevation, intensity), validated with Monte Carlo simulation, and their spatial filtering described using spherical harmonic analysis. Observations from an ensemble of modeled receptive fields are obtained by linking the inverse Gaussian density to the probabilistic inverse problem of estimating sound-source direction and intensity. Upper bounds on acuity is derived from the ensemble using Fisher information, and the predicted patterns of estimation errors are related to psychophysical performance.

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