Sound pressure was mapped in the bony ear canal of gerbils during closed-field sound stimulation at frequencies from 0.1 to 80 kHz. A 1.27-mm-diam probe-tube microphone or a 0.17-mm-diam fiber-optic miniature microphone was positioned along approximately longitudinal trajectories within the 2.3-mm-diam ear canal. Substantial spatial variations in sound pressure, sharp ...

When the frequency range over which vent-transmitted sound dominates amplification increases, the potential benefit from directional microphones and noise reduction decreases. Fitted with clinically appropriate vent sizes, 23 aided listeners with varying low-frequency hearing thresholds evaluated six schemes comprising three levels of gain at 250 Hz (0, 6, and 12 ...

This article discusses two experiments on the discrimination of time intervals presented in sequences marked by brief auditory signals. Participants had to indicate whether the last interval in a series of three intervals marked by four auditory signals was shorter or longer than the previous intervals. Three base durations were ...

We aimed at testing the cortical representation of complex natural sounds within auditory cortex by conducting 2 human magnetoencephalography experiments. To this end, we employed an adaptation paradigm and presented subjects with pairs of complex stimuli, namely, animal vocalizations and spectrally matched noise. In Experiment 1, we presented stimulus pairs ...

This study investigated effects of a previous sound presentation at the absolute threshold of hearing. Changes in threshold were measured when a pure tone at 60 dB SPL preceded a test tone in the contra- or ipsilateral ear. When the previous and test sounds both had the same frequency of ...

A technique for the recording of large sets of room impulse responses or head-related transfer functions is presented. The technique uses a microphone moving with constant speed. Given a setup (e.g., length of the room impulse response), a careful choice of the recording parameters (excitation signal, speed of movement) leads ...

We examined peripheral and central nervous cues underlying the ability of the bushcricket Leptophyes punctatissima to orient to elevated and depressed sound sources broadcasting the female acoustic reply. The peripheral spatial directionality of the ear was measured physiologically using monaural preparations of an auditory interneuron (T-fibre). In the azimuth, maximal ...

Dwellings in congested urban areas are confronted with both invigorating and aggravating penetrations of proximic sound and street activity within constricted environments. Typically the physicality of a building is there to serve as SHELTER from weather, intruders, and to create an interior effect. Here building elements, both physical and electronic, ...

It is unclear how well harbor porpoises can locate sound sources, and thus can locate acoustic alarms on gillnets. Therefore the ability of a porpoise to determine the location of a sound source was determined. The animal was trained to indicate the active one of 16 transducers in a 16-m-diam ...

A theory and experimental results for sound propagation through an anisotropic shallow water environment are presented to examine the frequency dependence of the scintillation index in the presence of internal waves. The theory of horizontal rays and vertical modes is used to establish the azimutal and frequency behavior of the ...

Four experiments investigated the acoustical correlates of similarity and categorization judgments of environmental sounds. In Experiment 1, similarity ratings were obtained from pairwise comparisons of recordings of 50 environmental sounds. A three-dimensional multidimensional scaling (MDS) solution showed three distinct clusterings of the sounds, which included harmonic sounds, discrete impact sounds, ...

Ultrasonic parameters including sound velocity and attenuation coefficient have recently been found to be useful in characterizing the cataract lens noninvasively. However, the regional changes of these acoustic parameters in the lens cannot be detected directly by those ultrasonic measurements. This prompted us to fabricate a 46-MHz needle transducer (lead ...

Our ability to understand auditory signals depends on properly separating the mixture of sound arriving from multiple sources. Sound elements tend to belong to only one object at a time, consistent with the principle of disjoint allocation, although there are instances of duplex perception or coallocation, in which two sound ...

Sound localization plays an important role in everyday life. It helps us to separate sounds coming from different sources and thus to acquire acoustic information. This paper describes an algorithm for localizing the position of a sound source, as recorded by dummy head microphones. The recorded signals are considered to ...

The sensation of touch, gravity, and sound all rely on dedicated ion channels that transduce mechanical stimulus forces into electrical signals. The functional workings and molecular identities of these mechanotransducer channels are little understood. Recent work shows that the mechanotransducers for fly and vertebrate hearing share equivalent gating mechanisms, whereby ...

During a combined visual and acoustic cetacean survey of the Hawaiian Islands in 2002, four midfrequency sounds were recorded in close proximity to a group of Blainville's beaked whales, Mesoplodon densirostris. These sounds included one frequency-modulated whistle, and three frequency- and amplitude-modulated pulsed sounds, with energy between 6 and 16 ...

Studies of underwater hearing are often hampered by the behavior of sound waves in small experimental tanks. At lower frequencies, tank dimensions are often not sufficient for free field conditions, resulting in large spatial variations of sound pressure. These effects may be mitigated somewhat by increasing the frequency bandwidth of ...

Centrifugal olivocochlear (OC) pathways modulate cochlear hearing desensitization induced by loud sounds, but there is a null point, determined by sound bandwidth, for this effect. In a previous study, using loud sounds from the region of greatest hearing sensitivity in cats, OC pathways did not affect desensitization induced by 2-kHz ...

Research on event-related potential (ERP) correlates of auditory deviance-detection in newborns provided inconsistent results; temporal and topographic ERP characteristics differed widely across studies and individual infants. Robust and reliable ERP responses were, however, obtained to sounds (termed 'novel' sounds), which cover a wide range of frequencies and widely differ from ...

OBJECTIVE: This study investigated speech, environmental sounds (naturally occurring sounds with arbitrary meanings), auditory icons (natural or synthetic sounds with specific meanings), and abstract synthetic warnings as candidates for within-vehicle interfaces. BACKGROUND: Auditory displays and warnings must satisfy certain criteria, such as being appropriately urgent and commanding appropriately fast response ...

This paper reports the first systematic study of acoustic signals during social interactions of the Chinese alligator (Alligator sinensis). Sound pressure level (SPL) measurements revealed that Chinese alligators have an elaborate acoustic communication system with both long-distance signal-bellowing-and short-distance signals that include tooting, bubble blowing, hissing, mooing, head slapping and ...

In order to find out the most suitable and accurate pointing methods to study the sound localizability of persons with visual impairment, we compared the accuracy of three different pointing methods for indicating the direction of sound sources in a semi-anechoic dark room. Six subjects with visual impairment (two totally ...

In an earlier investigation [Sivonen and Ellermeier, J. Acoust. Soc. Am. 119, 2965-2980 (2006)], the effect of sound incidence angle on loudness was investigated for anechoic, narrowband sounds. In the present follow-up investigation, the effect of incidence angle on loudness was investigated using wideband sounds under anechoic conditions and narrowband ...

Big brown bats (Eptesicus fuscus) were videotaped in the dark with a night-vision lens and infrared illumination while flying repeatedly along the same straight course to seize a tethered mealworm or a small electret microphone used to record biosonar signals impinging on the target. Bats emitted frequency-modulated sounds with first ...

Transient auditory stimuli have been shown to influence the perception of ambiguous 2D visual motion displays (the bouncing-disks effect; e.g. Sekuler et al. in Nature 385:308, 1997). The question addressed here was whether continuous moving auditory stimuli can also influence visual motion perception under the same experimental conditions. In Experiment ...

Posture control is mediated by the integration between the environment information (coming from the visual, somatosensory and vestibular systems) and the efferent organs (motoneurons and muscles). The influence of the first systems on body sway signals is already documented in the literature. Few studies are focused in the relationship between ...

Acoustic signals produced by caterpillars have been documented for over 100 years, but in the majority of cases their significance is unknown. This study is the first to experimentally examine the phenomenon of audible sound production in larval Lepidoptera, focusing on a common silkmoth caterpillar, Antheraea polyphemus (Saturniidae). Larvae produce ...

Bone conduction (BC) relative to air conduction (AC) sound field sensitivity is here defined as the perceived difference between a sound field transmitted to the ear by BC and by AC. Previous investigations of BC-AC sound field sensitivity have used different estimation methods and report estimates that vary by up ...

The ability of the bushcricket Leptophyes punctatissima to orient to elevated sound sources was investigated. Males were placed on a walking compensator and oriented in response to a synthetic female reply, which was broadcast via one of five loudspeakers placed at elevations of 0 degrees , 30 degrees , 60 ...

OBJECTIVES: (1) To develop a cadaveric temporal-bone preparation to study the mechanism of hearing loss resulting from superior semicircular canal dehiscence (SCD) and (2) to assess the potential usefulness of clinical measurements of umbo velocity for the diagnosis of SCD. BACKGROUND: The syndrome of dehiscence of the superior semicircular canal ...

The task of assigning concurrent sounds to different auditory objects is known to depend on temporal and spectral cues. When tones of high and low frequencies are presented in alternation, they can be perceived as a single, integrated melody, or as two parallel, segregated melodic lines, according to the presentation ...

The analysis of the auditory scene begins from the moment we hear sounds, making it possible for the infant to distinguish the mother's voice from other sounds in the environment. The purpose of the study was to determine, in two experiments, whether the frequency separation threshold, at which the perception ...

BACKGROUND: Doctors are exhorted to always place the stethoscope directly on the skin and never to auscultate through clothing. Nevertheless, casual observation reveals that doctors and even pulmonologists often violate this principle. OBJECTIVES: This study was designed to evaluate the sensitivity of two common stethoscopes when used through clothing. METHODS: ...

We measured the sound level and frequencies of the acoustic noise generated by a 3 Tesla (T) MR scanner, and investigated the subjective sound level for 30 healthy volunteers with either earplugs, headphones or both. The sound level of 3T was found to be higher than that of 1.5T in ...

Impulse sound events are characterised by ultra high pressures and low frequencies. Lower frequency sounds are generally less attenuated over a given distance in the atmosphere than higher frequencies. Thus, impulse sounds can be heard over greater distances and will be more affected by the environment. To calculate a long-term ...

This study analyzes the heart rate and voice response of young students while walking or listening to sounds based on 1/f (f=frequency) fluctuation using FFT spectral analysis. There was more positive 1/f fluctuation in heart rate response in normal walking or while listening to comfortable sounds than under stressful conditions, ...

In recent years swallowing sounds analysis have received great attention for observing the abnormalities in swallowing mechanisms. In this paper a comprehensive set of features were extracted from time and frequency domains characteristics of the signals. 111 features were obtained from different parts of swallowing sounds including initial discrete sounds ...

Sound transmission has been of interest for many years in an attempt to study the structure of the lung and different researches have shown that artificial sounds produce a lateralization of sound information at the thoracic surface. Most of these studies have use non-simultaneous recording and input sounds introduced at ...

Hearing impaired persons (HIPs) are afraid of walking along a street and living a life alone. If they can successfully get sound information via some machine interface, dangerous situations outdoors will be avoided, and their quality of life indoors will be improved. This paper describes a notification system for transmitting ...

Arguably sensory systems, including audition, evolved allowing animals to navigate, find prey, avoid predators, mate, and, for some species, communicate. All of these essential functions require animals to determine objects in their environment. Vibrating objects produce a sound pressure wave that has the potential of informing an animal about these ...

Several studies have shown a right-hemispheric advantage for sound localisation. However, most of these studies used stationary sound stimuli, although in most everyday situations humans are in motion when localising sound, or face a moving sound source. To elucidate the question of a functional asymmetry in cortical processing of auditory ...

When two discrete stimuli are presented in rapid succession, observers typically report a movement of the lead stimulus toward the lag stimulus. The object of this study was to investigate crossmodal effects of irrelevant sounds on this illusion of visual apparent motion. Observers were presented with two visual stimuli that ...

BACKGROUND: In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m ...

Many night-flying insects evolved ultrasound sensitive ears in response to acoustic predation by echolocating bats . Noctuid moths are most sensitive to frequencies at 20-40 kHz , the lower range of bat ultrasound . This may disadvantage the moth because noctuid-hunting bats in particular echolocate at higher frequencies shortly before ...

Butterflyfishes are conspicuous members of coral reefs and well known for their visual displays during social interactions. Members of the genus Chaetodon have a unique peripheral arrangement of the anterior swim bladder that connects with the lateral line (the laterophysic connection) and in many species projects towards the inner ear. ...

Speech can be recognized by multiple acoustic cues in both frequency and time domains. These acoustic cues are often thought to be redundant. One example is the low-frequency sound component below 300 Hz, which is not even transmitted by the majority of communication devices including telephones. Here, we showed that ...

Blainville's beaked whales (Mesoplodon densirostris Blainville) echolocate for prey during deep foraging dives. Here we use acoustic tags to demonstrate that these whales, in contrast to other toothed whales studied, produce two distinct types of click sounds during different phases in biosonar-based foraging. Search clicks are emitted during foraging dives ...

Sound plays an important role in the life history of mosquitoes. Male mosquitoes detect females by the sound generated by their wingbeat. Because female wings are weak acoustic radiators, males have been driven by sexual selection to evolve sensitive acoustic sensors. Mosquito antennae are very sensitive acoustic receivers, featuring up ...

This paper reports on the acute effects of a monaural plug on directional hearing in the horizontal (azimuth) and vertical (elevation) planes of human listeners. Sound localization behavior was tested with rapid head-orienting responses toward brief high-pass filtered (>3 kHz; HP) and broadband (0.5-20 kHz; BB) noises, with sound levels ...

The optic tectum of the barn owl contains a map of auditory space. We found that, in response to moving sounds, the locations of receptive fields that make up the map shifted toward the approaching sound. The magnitude of the receptive field shifts increased systematically with increasing stimulus velocity and, ...