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At least 1,441 records · Page 80Linked to original sources
PubMed2001

Mice and humans perceive multiharmonic communication sounds in the same way.

Vowels and voiced consonants of human speech and most mammalian vocalizations consist of harmonically structured sounds. The frequency contours of formants in the sounds determine their spectral shape and timbre and carry, in human speech, important phonetic and prosodic information to be communicated. Steady-state partitions of vowels are discriminated and identified mainly on the basis of harmonics or formants having been resolved by the critical-band filters of the auditory system and then grouped together. Speech-analog processing and perception of vowel-like communication sounds in mammalian vocal repertoires has not been demonstrated so far. Here, we synthesize 11 call models and a tape loop with natural wriggling calls of mouse pups and show that house mice perceive this communication call in the same way as we perceive speech vowels: they need the presence of a minimum number of formants (three formants-in this case, at 3.8 + 7.6 + 11.4 kHz), they resolve formants by the critical-band mechanism, group formants together for call identification, perceive the formant structure rather continuously, may detect the missing fundamental of a harmonic complex, and all of these occur in a natural communication situation without any training or behavioral constraints. Thus, wriggling-call perception in mice is comparable with unconditioned vowel discrimination and perception in prelinguistic human infants and points to evolutionary old rules of handling speech sounds in the human auditory system up to the perceptual level.

Age Factors↗
PubMed1998

Stress reaction to intense sound exposure under different arousal levels in guinea pigs.

The general impact of high intensity sound exposure on 25 guinea pigs was investigated at three different levels of arousal: 10 during general anaesthesia. 10 during partial arousal, and 5 during complete arousal. Parameters recorded before and during noise exposure were mean arterial blood pressure, pulse rate, and plasma norepinephrine levels. The anaesthetized group showed no increase in the three parameters during sound exposure. Under partial arousal, pulse rate and norepinephrine level increased significantly: pulse rate from 224.5 beats/min before exposure to 278.6 beats/min during exposure, and norepinephrine level from 558 pg/ml before sound exposure to 1276 pg/ml during exposure. At the time of the complete arousal state norepinephrine and pulse rates increased significantly during noise exposure, while blood pressure showed no additional increase as a result of sound exposure.

Acoustic Stimulation↗
PubMed2004

Auditory alerts for in-vehicle information systems: the effects of temporal conflict and sound parameters on driver attitudes and performance.

In-vehicle information systems will soon confront drivers with an increasing number of warnings and alerts for situations ranging from imminent collisions to the arrival of e-mail messages. Coordinating these alerts can ensure that they enhance rather than degrade driving safety. Two experiments examined how temporal conflict and sound parameters affect driver performance and acceptance. The temporal conflict of an e-mail alert occurring 300 ms before a collision warning interfered with the response to the collision warning, but an e-mail alert occurring 1000 ms before the collision warning had the opposite effect and enhanced the response to the collision warning. These results emphasize the need to consider how in-vehicle devices influence drivers' strategic anticipation of high-demand situations. Regarding sound parameters, results showed that highly urgent sounds tended to speed drivers' accelerator release, but the annoyance associated with highly urgent sounds increased workload. In fact, there was a strong positive association between ratings of annoyance and subjective workload. Consistent with the urgency mapping principle, there was a slight negative association between the differences in the rated urgency of collision warnings and e-mail alerts and subjective workload. The results suggest that warning and alert design should consider an annoyance trade-off in addition to urgency mapping.

Accidents, Traffic↗
PubMed1988

Interaural transfer of aftereffect of changing sound level in a tone.

Monaural and interaural aftereffects of unidirectional change of sound level in a tone, were measured by a nulling procedure. The former were always much greater than the latter, demonstrating limited interaural transfer of the aftereffect. This is seen as evidence for a peripheral component in the analysis of changing sound level. Such analysis may contribute to the localization of moving sound sources. An additional, and incidental, finding was that a tone without adaptation elicited a perception of steady loudness when its sound level was diminishing slightly. This is consistent with previous evidence.

Adult↗
PubMed1992

Changing-loudness aftereffect following simulated movement: implications for channel hypotheses concerning sound level change and movement.

Listening to a tone changing unidirectionally in sound level causes an illusion of changing loudness in a steady tone afterward. This aftereffect may indicate channels for detecting the feature of change in sound level, which would primarily concern dynamic sound localization. Three subjects, one of whom was the author, participated in this study. The author predicted that opposite adaptation of the ears (the adapting stimulus is heard to move from one ear to the other) should lead to a movement aftereffect. This was not reported by the subjects. However, the subjects did report a changing-loudness aftereffect in a monaural test stimulus, and the characteristics of the changing-loudness aftereffect (such as its magnitude) were consistent with previous data, suggesting a two-stage channel hypothesis: Output from channels for several features, including sound-level change, simultaneously stimulate movement channels.

Attention↗
PubMed1982

Evaluation of heart sounds and murmurs in children.

Auscultation is the core of pediatric cardiovascular evaluation and should be performed according to a routine. The four heart sounds should be sought in order at their usual locations, with particular attention to the second sound because of its important diagnostic role in congenital cyanotic heart disease. The next sounds to listen for are clicks, which can be systolic, pulmonary, aortic, or midsystolic. Finally, murmurs should be sought in systole and then diastole. Besides being identified as systolic, diastolic, or continuous, murmurs should be characterized according to their relationship with the first and second heart sounds, intensity, frequency, and maximum location and radiation.

Adolescent↗
PubMed1998

Speech sound perception and learning: biologic bases.

Historically, auditory research has focused predominantly on how relatively simple acoustic signals are represented in the neuronal responses of the auditory periphery. However, in order to understand the neurophysiology underlying speech perception, the ultimate objective is to discover how speech sounds are represented in the central auditory system and to relate that representation to the perception of speech as a meaningful acoustic signal. This paper reviews three areas pertaining to the central auditory representation of speech: (1) the differences in neural representation of speech sounds at different levels of the auditory system, (2) the relation between the representation of sound in the auditory pathway and the perception/misperception of speech, and (3) the plasticity of speech-sound neural representation and speech perception.

Auditory Pathways↗
PubMed2000

Newborn infants' cry after heel-prick: analysis with sound spectrogram.

The aim of the study was to test the hypothesis that a newborn infant's cry can be used in conjunction with an instrument to measure pain. Crying due to pain was analysed after a heel-prick stimulus. In a prospective, descriptive study, 50 healthy newborn infants were subjected to a heel-prick for phenylketonuria screening. Their cries of pain were recorded and analysed. Duration of the crying sound was analysed and, using a sound spectrogram, the fundamental frequency and the cry melody of the first five cry sounds were analysed. The analysis showed that the crying sound after the painful stimulus of the heel-prick had a significantly higher fundamental frequency and lasted longer at the first than at the fifth cry. The first cry had a more varied crying melody than the fifth. There were large differences between individual cries from a single infant, as well as in the duration of each cry, total crying time, and fundamental frequencies between infants. While the first cry was more like a cry of pain, the fifth cry more resembled crying for reasons other than pain. The results suggest that newborn infants react to pain in a recognizable way. However, other stimuli may cause a similar reaction. Crying can therefore be used to measure pain in newborn infants only when the cause of crying is known.

Blood Specimen Collection↗
PubMed1990

Comparison of three clinical techniques for evaluating joint sounds.

Two-hundred two consecutive adult patients presenting to the University of Kentucky for general dental care screening were examined for temporomandibular joint sounds by three techniques: (1) lateral pole surface palpation, (2) digital palpation in the external auditory canal, (3) auscultation by a stethoscope. Sixty-nine patients reported joint sounds, but only 32 had sounds diagnosed by auscultation resulting in a 54% false-negative reporting rate. Stethoscopic auscultation was used as the standard to which the other two techniques were compared. The false-negative rate for auditory canal digital palpation was 71% and 77% for lateral pole surface palpation. Surface palpation had only a 2% false-positive incidence while auditory canal digital palpation had a 51% false-positive rate. There was poor agreement between the patients' subjective reporting and clinical exam by any technique. Using stethoscopic auscultation as the standard, both auditory canal and surface palpation had a very high false-negative rate, but only the auditory canal palpation had a poor false-positive incidence. Auditory canal palpation often produces TMJ sounds that are not heard with a stethoscope during normal opening and closure.

Adult↗
PubMed1996

Subjective Annoyance Response to Diesel Engine Sound During Idling Conditions.

Subjective annoyance response to diesel engine sound during idling conditions was evaluated by 80 participants. Eight different sound spectra were presented to the participants at a constant level of 80 dB(A) in a paired comparison procedure. Stereo-recorded sound stimuli were played back through a pair of loudspeakers in an anechoic room. Four objective parameters of loudness, sharpness, impulsiveness, and roughness were found to be the determining factors that cause subjective annoyance. An annoyance prediction model for the test stimuli of an idling diesel engine was developed on the basis of these factors. The objective parameters and their interactions have a significant effect on the annoyance prediction model. The spectral distribution indicated by test participants to be pleasant can be used as a basis for appropriate modification of engine sound. A single microphone measurement in free field conditions can be used to estimate objective parameters for defining the cause of annoyance.

diesel engine↗
PubMed2005

Sound quality judgements of new hearing instrument users over a 24-week post-fitting period.

The time course of changes in perceived sound quality after hearing instrument fitting has not been studied systematically It is possible, for example, that patients may object to additional high frequency gain when fitted, but not after a period of auditory acclimatisation. The aim of this study was to utilise sound quality judgements to compare two frequency responses in new users at 4-week intervals over a 24-week post-fitting period. The null hypothesis was that there would be no change in sound quality judgements over time. A total of 16 elderly subjects were fitted monaurally with the same model of linear, programmable hearing instrument. This was set to a standard response that provided 26-29 dB of real-ear insertion gain at 2000 4000 Hz. This program was worn by the subjects for the duration of the study. All subjects reported greater than four hours of daily use. The alternative response which was used in a paired comparison paradigm, provided a mean gain reduction of 3, 8, 13, and 16 dB at 2000, 3000, 4000 and 6000 Hz, respectively. Subjects compared the standard and the alternative responses for sound quality along dimensions of comfort, clarity, and overall preference while listening to running speech presented in quiet, steady noise, and speech babble. At the time of fitting there was a small preference for the standard response when judging clarity, but the alternative response was preferred for comfort and preferred overall. Repeated-measures analysis of variance (ANOVA) for each quality dimension did not reveal any statistically significant change over time. It is concluded that this pattern of preference is unaffected by acclimatisation to amplification, at least over the initial 24 weeks of instrument use.

Acoustics↗
PubMed1994

Laser and sound scanner for non-contact 3D volume measurement and surface texture analysis.

Non-invasive three-dimensional measurement of volume and analysis of surface texture is desired in various medical applications, particularly wound healing measurements. In this paper we present a PC-based non-contact laser scanner for volume measurements, and a sound scanner that can accurately measure volumes and analyse surface textures. The non-invasive laser and sound sensors, which are lightweight, are mounted inverted on an X-Y table and the sensor heads are held at a distance of 3 cm from the object to be scanned. Volumes of various shapes on different materials, simulating depth profiles and surfaces of wounds, have been measured accurately and surface textures of varying softness have been analysed. The ratios of measured to actual volume range between 0.8 for the sound sensor and 1.1 for the laser sensor. A linear relation between hardness of 50%-20% concentration gelatin gel surfaces and amplitude of reflected sound waves is also observed. The average time per pass of a scan, for a distance of 3 cm, is 4 s and the computation time for measuring volume and reconstruction of a 3D image using ten passes per scan is 1 min. The unique features of this scanner are its speed, portability, accuracy and simple operation as well as its ability to be used on both soft and hard surfaces.

Humans↗
PubMed1988

Effects of sounds presented during general anaesthesia on postoperative course.

In a double-blind, randomized study, patients undergoing cholecystectomy were administered one of four different sounds during general anaesthesia: positive suggestions, nonsense suggestions, seaside sounds or sounds from the operating theatre. The effect of these sounds on the postoperative course was examined to assess intraoperative auditory registration. No differences were found between the four groups in postoperative variables.

Adult↗
PubMed1994

Mid-latency auditory evoked potentials and circulatory response to loud sounds.

We investigated in 60 patients scheduled for elective aorto-coronary bypass grafting if loud sounds by themselves can induce cardiovascular responses and if these could be related to mid-latency auditory evoked potentials (MLAEP). Anaesthesia was induced in group I (n = 20) with flunitrazepam-fentanyl 0.01 mg kg-1 and maintained with flunitrazepam-fentanyl 1.2 mg h-1. Patients in groups II (n = 20) and III (n = 20) received etomidate 0.25 mg kg-1 and fentanyl 0.005 mg kg-1 for induction and 0.6-1.2 vol% isoflurane and fentanyl 1.2 mg h-1, or propofol 4-8 mg kg-1 h-1 and fentanyl 1.2 mg h-1 for maintenance of general anaesthesia. After preparation of the sternum the operation was stopped for several minutes. Then, as a loud auditory stimulus, the sound of the running sternotomy saw was presented to the patients by putting the saw inverted on the sternum for several seconds. Heart rate (HR), arterial pressure (SAP), pulmonary capillary wedge pressure (PCWP), cardiac index, systemic vascular resistance and MLAEP were measured in the awake state, before and after presentation of the sound. Latencies of the peak V, Na, Pa, Nb and P1 were measured. In group I there were statistically significant increases in HR (63.5-70.2 beat min-1), SAP (123.9-146-5 mm Hg) and PCWP (9.2-11.7 mm Hg) after presentation of the sound. These haemodynamic changes were not observed in patients in groups II and III. In the awake state, AEP had high peak -to-peak amplitudes and a periodic waveform.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Inhalation↗
PubMed1994

Non-verbal environmental sound recognition after unilateral hemispheric stroke.

Recognition of non-verbal environmental sounds was investigated in 52 subjects with unilateral cerebro-vascular accidents and 18 age-matched normal controls. Impaired performance was most consistently found following cortical damage of homologous areas in either the left or the right hemisphere. Lesions involved the superior temporal gyrus (including the planum temporale), the inferior parietal lobe and the parietal operculum; this area appears to constitute the human auditory cortical processing area. We found different error patterns dependent upon the side of the lesion: patients with right hemisphere damage failed to discriminate between acoustically related sounds, patients with left hemisphere lesions tended to confuse semantically related sound sources. The impairment following right hemisphere damage was specific for non-verbal environmental sounds while left hemisphere damage was associated with disturbed semantic capabilities in multiple modalities.

Aged↗
PubMed1995

The functional anatomy of recovery from auditory agnosia. A PET study of sound categorization in a neurological patient and normal controls.

H2(15)O-PET was used to investigate the functional anatomy of recovery in a patient (J.B.) with bilateral perisylvian strokes and auditory agnosia, who partially regained the ability to recognize environmental sounds, but remained clinically word-deaf. The patient and a group of six normal volunteers were scanned in the following three conditions: (i) passive listening to environmental sounds; (ii) categorization of environmental sounds; (iii) at rest. In normal subjects, passive listening as compared with rest was associated with significant activations in the auditory cortices and posterior thalami, and in the inferior parietal lobe and anterior insula/frontal opercular region on the right. In J.B., activations were observed in the spared auditory cortex and inferior parietal lobe of the right hemisphere and in regions adjacent to the perisylvian lesion in the left hemisphere (anterior insula/frontal opercular region, middle temporal gyrus and inferior parietal lobe). The recovered function, as measured by categorization of sounds compared with passive listening, in J.B. was associated with bilateral activation of a distributed network comprising (pre)frontal, middle temporal and inferior parietal cortices, as well as the right cerebellum and the right caudate nucleus. In addition, there was a left-sided activation of the anterior cingulate gyrus. In normal subjects, the same categorization task led to activation of a network comprising (pre)frontal, middle temporal and inferior parietal cortices in the left hemisphere only. These results suggest that bilateral activation (with recruitment of areas homologous to those known to be responsible for normal function), the engagement of peri-infarct regions, and the involvement of a more widespread neocortical network, are mechanisms of functional reorganization after injury that may enable recovery from, or compensation for, cognitive deficits.

Agnosia↗
PubMed2003

Neural resources for processing language and environmental sounds: evidence from aphasia.

Although aphasia is often characterized as a selective impairment in language function, left hemisphere lesions may cause impairments in semantic processing of auditory information, not only in verbal but also in nonverbal domains. We assessed the 'online' relationship between verbal and nonverbal auditory processing by examining the ability of 30 left hemisphere-damaged aphasic patients to match environmental sounds and linguistic phrases to corresponding pictures. The verbal and nonverbal task components were matched carefully through a norming study; 21 age-matched controls and five right hemisphere-damaged patients were also tested to provide further reference points. We found that, while the aphasic groups were impaired relative to normal controls, they were impaired to the same extent in both domains, with accuracy and reaction time for verbal and nonverbal trials revealing unusually high correlations (r = 0.74 for accuracy, r = 0.95 for reaction time). Severely aphasic patients tended to perform worse in both domains, but lesion size did not correlate with performance. Lesion overlay analysis indicated that damage to posterior regions in the left middle and superior temporal gyri and to the inferior parietal lobe was a predictor of deficits in processing for both speech and environmental sounds. The lesion mapping and further statistical assessments reliably revealed a posterior superior temporal region (Wernicke's area, traditionally considered a language-specific region) as being differentially more important for processing nonverbal sounds compared with verbal sounds. These results suggest that, in most cases, processing of meaningful verbal and nonverbal auditory information break down together in stroke and that subsequent recovery of function applies to both domains. This suggests that language shares neural resources with those used for processing information in other domains.

Adult↗
PubMed2002

Intrinsic optical signals from rat primary auditory cortex in response to sound stimuli presented to contralateral, ipsilateral and bilateral ears.

In the auditory cortex, primitive features of acoustic stimuli are represented for auditory scene analysis. A typical example of a feature representation is the tonotopic map, in which sound frequencies are spatially arranged in an orderly manner. Some neurons in the auditory cortex are sensitive to sound source location, which is another important feature for auditory scene analysis. In the present study, using the intrinsic optical imaging technique, we attempted to visualize the two-dimensional pattern of neuronal population responses in the primary auditory cortex of rats to pure tones presented at various frequencies and sound intensities. The observed arrangements of sound frequencies were consistent with those obtained by electrophysiological mapping, which indicates that our intrinsic optical recording can visualize populational responses of neurons. We also found different temporal patterns of intrinsic signals elicited in response to contralateral, ipsilateral, and bilateral ear stimulations. Finally we try to explain the observed differential time courses of intrinsic signal responses from the theoretical point of view on the conduction of neural activities, based on the so far anatomically identified neural pathways in the rodent auditory system.

Acoustic Stimulation↗