Types Of Acoustic Stimuli Research Articles

Does the Number of Stimuli Influence the Formation of the Endogenous Components of the Event-Related Auditory Evoked Potentials?

Introduction The number of stimuli is important to determine the quality of auditory evoked potential records. However, there is no consensus on that number in studies, especially in the sample studied. Objectives To investigate the influence of the number of rare stimuli on forming N2 and P3 components, with different types of acoustic stimuli. Methods Cross-sectional, descriptive, comparative study, approved by the ethics committee of the institution. The sample comprised 20 normal hearing adults of both sexes, aged 18 to 29 years old, with normal scores in the mental state examination and auditory processing skills. The event-related auditory evoked potentials were performed with nonverbal (1 kHz versus 2 kHz) and verbal stimuli (/BA/ versus /DA/). The number of rare stimuli varied randomly in the recordings, with 10, 20, 30, 40, and 50 presentations. Results P3 latency was significantly higher for nonverbal stimuli with 50 rare stimuli. N2 latency did not show any difference between the type and number of stimuli. The absolute P3 and N2-P3 amplitudes showed significant differences for both types of stimuli, with higher amplitude for 10 rare stimuli, in contrast with the other ones. The linear tendency test indicated significance only for the amplitude - as the number of rare stimuli increased, the amplitude tended to decrease. Conclusion The components were identifiable in the different numbers of rare stimuli and types of stimuli. The P3 and N2-P3 latency and amplitude increased with fewer verbal and nonverbal stimuli. Recording protocols must consider the number of rare stimuli.

Intra-individual Reliability of Voice- and Music-elicited Responses and their Modulation by Expertise

A growing number of functional neuroimaging studies have identified regions within the temporal lobe, particularly along the planum polare and planum temporale, that respond more strongly to music than other types of acoustic stimuli, including voice. This “music preferred” regions have been reported using a variety of stimulus sets, paradigms and analysis approaches and their consistency across studies confirmed through meta-analyses. However, the critical question of intra-subject reliability of these responses has received less attention. Here, we directly assessed this important issue by contrasting brain responses to musical vs. vocal stimuli in the same subjects across three consecutive fMRI runs, using different types of stimuli. Moreover, we investigated whether these music- and voice-preferred responses were reliably modulated by expertise. Results demonstrated that music-preferred activity previously reported in temporal regions, and its modulation by expertise, exhibits a high intra-subject reliability. However, we also found that activity in some extra-temporal regions, such as the precentral and middle frontal gyri, did depend on the particular stimuli employed, which may explain why these are less consistently reported in the literature. Taken together, our findings confirm and extend the notion that specific regions in the brain consistently respond more strongly to certain socially-relevant stimulus categories, such as faces, voices and music, but that some of these responses appear to depend, at least to some extent, on the specific features of the paradigm employed.

Effects of Acoustic Stimuli Complementing Out-Of-Home Advertising

Consumers are being exposed to an evergrowing number of promotional offers. Therefore, innovative communication measures are required to deliver advertising messages to potential customers effectively. The present work investigates the interaction of acoustic and visual stimuli of an advertising campaign in the out-of-home arena. Research into the integration of these two modalities has so far received little attention in the literature. The investigations focus on the effects of the multisensory integration of a poster with two types of acoustic stimuli: verbal slogans and the sounds of products which can be heard when they are being consumed. Neural research into human information processing provides the basis for the development of a number of hypotheses. A field experiment comprising two quantitative studies involves a poster presented in a citylight accompanied by acoustic cues. Passers-by are exposed the poster and one of two sounds or only the poster. Means of observation and communication measure the resulting effects in terms of attention, brand recognition, ad intrusiveness, and attitude toward the brand, and the findings result from the comparison between the three groups. Three main results which contribute to our understanding of the field stand out: Acoustic signals increase attention and to a certain degree brand recognition but at the same time they are perceived as being intrusive. Cooperation with two companies (one which hires out space for out-of-home advertising and a producer of dairy products) ensures the practical relevance of this research. We recommend considering the combining of out-ofhome advertising with acoustic stimuli for selected projects thereby carefully balancing the advantages of attention generation with the disadvantages of perceived ad intrusiveness.

Laterality in Responses to Acoustic Stimuli in Giant Pandas.

Simple SummaryFunctional lateralization in the auditory system has been widely studied. Accordingly, behavioral laterality responses affected by acoustic stimuli have been observed in many vertebrate species. In this study, we assessed giant pandas’ behavioral responses to different acoustic stimuli in order to examine cerebral lateralization. We concluded that adult giant pandas showed a left-hemisphere bias in response to positive acoustic stimuli. Furthermore, we found the specific valence of cerebral lateralization for different categories of acoustic stimuli, of which some were relevant to the lateralization while others were not relevant. Our findings support an evolutionary strategy that giant pandas process auditory signals similar to other mammals.Cerebral lateralization is a common feature present in many vertebrates and is often observed in response to various sensory stimuli. Numerous studies have proposed that some vertebrate species have a right hemisphere or left hemisphere dominance in response to specific types of acoustic stimuli. We investigated lateralization of eight giant pandas (Ailuropoda melanoleuca) by using a head turning paradigm and twenty-eight acoustic stimuli with different emotional valences which included twenty-four conspecific and four non-conspecific acoustic stimuli (white noise, thunder, and vocalization of a predator). There was no significant difference in auditory laterality in responses to conspecific or non-conspecific sounds. However, the left cerebral hemisphere processed the positive stimuli, whereas neither of the two hemispheres exhibited a preference for processing the negative stimuli. Furthermore, the right hemisphere was faster than the left hemisphere in processing emotional stimuli and conspecific stimuli. These findings demonstrate that giant pandas exhibit lateralization in response to different acoustic stimuli, which provides evidence of hemispheric asymmetry in this species.

MEMRI for visualizing brain activity after auditory stimulation in frogs.

Anuran amphibians are common model organisms in bioacoustics and neurobiology. To date, however, most available methods for studying auditory processing in frogs are highly invasive and thus do not allow for longitudinal study designs, nor do they provide a global view of the brain, which substantially limits the questions that can be addressed. The goal of this study was to identify areas in the frog brain that are responsible for auditory processing using in vivo manganese-enhanced MRI (MEMRI). We were interested in determining if the neural processing of socially relevant acoustic stimuli (e.g., species-specific calls) engages a specific pattern of brain activation that differs from patterns elicited by less- or nonrelevant acoustic signals. We thus designed an experiment, in which we presented three different types of acoustic stimuli (species-specific calls, band-limited noise, or silence) to fully awake northern leopard frogs (Rana pipiens) and then conducted MEMRI T1-weighted imaging to investigate differences in signal intensity due to manganese uptake as an indication of brain activity across all three conditions. We found the greatest change in signal intensity within the torus semicircularis (the principal central auditory region), the habenula, and the paraphysis of frogs that had been exposed to conspecific calls compared with noise or silence conditions. Stimulation with noise did not result in the same activation patterns, indicating that signals with contrasting social relevance are differentially processed in these areas of the amphibian brain. MEMRI provides a powerful approach to studying brain activity with high spatial resolution in frogs. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Frequency-following responses elicited by a consonant-vowel with intonation

To date, two major types of acoustic stimuli have been used to evoke frequency-following responses (FFRs) – either by using a consonant-vowel or by using a vowel with intonation, but not both. The goals of this study were to (1) determine the feasibility of recording FFRs by forging a CV and intonation into one acoustic stimulus, and (2) examine the characteristics of such responses. Twelve Chinese adults (8 females, 4 males, age = 25.58 ± 4.23 years old) were recruited. FFRs were elicited by using the consonant-vowel /da/ combined with a rising intonation pattern (fundamental frequencies 85-93 Hz) for a total of 8000 sweeps from each participant. Six objective indices (Consonant Amplitude, Consonant Latency, Consonant Slope, Frequency Error, Tracking Accuracy and Pitch Strength) were derived from all recordings. Results demonstrated that it was feasible to record the consonant, vowel and intonation responses simultaneously. Results also demonstrated distinctive FFR trends with increasing number of sweeps for the consonant, vowel and intonation responses. Taken together, these findings may have important implications for basic research and clinical applications.To date, two major types of acoustic stimuli have been used to evoke frequency-following responses (FFRs) – either by using a consonant-vowel or by using a vowel with intonation, but not both. The goals of this study were to (1) determine the feasibility of recording FFRs by forging a CV and intonation into one acoustic stimulus, and (2) examine the characteristics of such responses. Twelve Chinese adults (8 females, 4 males, age = 25.58 ± 4.23 years old) were recruited. FFRs were elicited by using the consonant-vowel /da/ combined with a rising intonation pattern (fundamental frequencies 85-93 Hz) for a total of 8000 sweeps from each participant. Six objective indices (Consonant Amplitude, Consonant Latency, Consonant Slope, Frequency Error, Tracking Accuracy and Pitch Strength) were derived from all recordings. Results demonstrated that it was feasible to record the consonant, vowel and intonation responses simultaneously. Results also demonstrated distinctive FFR trends with increasing number of sweeps...

Roughness Prediction Based on a Model of Cochlear Hydrodynamics

Abstract The term roughness is used to describe a specific sound sensation which may occur when listening to stimuli with more than one spectral component within the same critical band. It is believed that the spectral components interact inside the cochlea, which leads to fluctuations in the neural signal and, in turn, to a sensation of roughness. This study presents a roughness model composed of two successive stages: peripheral and central. The peripheral stage models the function of the peripheral ear. The central stage predicts roughness from the temporal envelope of the signal processed by the peripheral stage. The roughness model was shown to account for the perceived roughness of various types of acoustic stimuli, including the stimuli with temporal envelopes that are not sinusoidal. It thus accounted for effects of the phase and the shape of the temporal envelope on roughness. The model performance was poor for unmodulated bandpass noise stimuli.

ELECTRIC AND ACOUSTIC DYNAMIC RANGES AND LOUDNESS GROWTH FUNCTIONS: A WITHIN-SUBJECT COMPARISON IN COCHLEAR IMPLANT PATIENTS

Objectives(1) To estimate the dynamic range (DR) for electric stimulation by means of acoustic and electric loudness matching; (2) to characterize loudness growth as a function of electric stimulus amplitude across the DR.DesignProspective study.Study DesignThree cochlear implant subjects, with normal hearing in the contralateral ear, participated in this study (ME28, ME-29, ME-30). For each electrode, the upper limit of electric stimulation was loudness matched to three different types of pitch-matched acoustic stimuli. Within the electric DR, the 25%, 50%, and 75% points were loudness matched to the acoustic stimuli to create loudness growth functions.ResultsME-28’s DRs for electric stimulation were constant at 17–18 dB across electrodes. ME-29’s and ME-30’s DRs were narrower, at around 10 dB. For ME-28 and ME-30, none of the corresponding DRs for matched acoustic stimuli exceeded 50 dB. Only one of ME-29’s DRs exceeded 35 dB. Loudness growth functions showed a tendency for basal electrodes to have gentler overall slopes. For relatively high proportions of the DR, the three different types of acoustic stimuli tend to have similar loudness growth slopes. However at low levels, the fewer harmonics, the steeper the loudness growth.ConclusionsThere is qualitative and quantitative agreement but patterns of variation can also be observed.

Hemispheric specialization in domestic dogs (Canis familiaris) for processing different types of acoustic stimuli

Lateralization is considered to be a fundamental feature of vertebrate brains. The aim of the present study was to examine the impact of functional cerebral asymmetry on processing of auditory stimuli in the domestic dog (Canis familiaris) during the orientation reaction. The experiment was conducted on 46 dogs (25 females and 21 males). Four types of auditory stimuli were used in the experiment (three meaningful stimuli: cat meowing, dog barking, the "sit" command ("siad" in Polish), and a neutral word ("wir", meaning "whirl" in Polish). It was predicted that the orientation reaction (turning the head towards the stimuli) would take place only in the case of meaningful sounds. It was also expected that dogs would show consistent lateralization. As predicted, all three meaningful stimuli elicited the orientation reaction. The response of the examined dogs to cat meowing showed significant lateralization with dominant leftwards movement, which hints towards activation of the right cerebral hemisphere and may be related to strong emotions evoked by this stimulus. Contrary to results of previous studies, dogs reacting to dog barking turned their heads leftwards more often, which suggests activation of the right cerebral hemisphere, probably related to the emotional meaning of the stimulus. The "sit" command consistently evoked the orientation reaction but there was no significant lateralization of this movement.

Spatial organization of receptive fields in the auditory midbrain of awake mouse

Efficient encoding of sensory information can be implemented by heterogeneous response properties of neurons within sensory pathways. In the auditory system, neurons in the main auditory midbrain nucleus, the inferior colliculus (IC), show heterogeneous response properties to various types of acoustic stimuli including behaviorally relevant sounds. The receptive fields of these neurons, and their spatial organization, may reveal mechanisms that underlie response heterogeneity in the IC. The mouse is becoming an increasingly popular system for auditory studies and although some studies have examined spectral characteristics in the IC, most of these have been conducted in anesthetized animals. There were two goals of this study. The first goal was to examine the frequency representation of awake mouse IC in fine spatial resolution. The second goal was to determine whether there is a spatial organization of excitatory frequency tuning curves in the IC of awake mice. We achieved these goals by histologically reconstructing locations of single and multiunit recordings throughout the IC in a mouse strain with normal hearing (CBA/CaJ). We found that the tonotopic progression is discontinuous in mouse IC, and we found that there is no clear spatial organization of frequency tuning curve types. Rather, there is heterogeneity of receptive fields in the bulk of the IC such that frequency tuning characteristics and hence the structure of excitatory and inhibitory inputs does not depend on location in the IC. This heterogeneity likely provides a mechanism for efficient encoding of auditory stimuli throughout the extent of the mouse IC.

Early cortical damage in rat somatosensory cortex alters acoustic feature representation in primary auditory cortex

Early postnatal freeze-lesions to the cortical plate result in malformations resembling human microgyria. Microgyria in primary somatosensory cortex (S1) of rats are associated with a reduced behavioral detection of rapid auditory transitions and the loss of large cells in the thalamic nucleus projecting to primary auditory cortex (A1). Detection of slow transitions in sound is intact in animals with S1 microgyria, suggesting dissociation between responding to slow versus rapid transitions and a possible dissociation between levels of auditory processing affected. We hypothesized that neuronal responses in primary auditory cortex (A1) would be differentially reduced for rapid sound repetitions but not for slow sound sequences in animals with S1 microgyria. We assessed layer IV cortical responses in primary auditory cortex (A1) to single pure-tones and periodic noise bursts (PNB) in rats with and without S1 microgyria. We found that responses to both types of acoustic stimuli were reduced in magnitude in animals with microgyria. Furthermore, spectral resolution was degraded in animals with microgyria. The cortical selectivity and temporal precision were then measured with conventional methods for PNB and tone-stimuli, but no significant changes were observed between microgyric and control animals. Surprisingly, the observed spike rate reduction was similar for rapid and slow temporal modulations of PNB stimuli. These results suggest that acoustic processing in A1 is indeed altered with early perturbations of neighboring cortex. However, the type of deficit does not affect the temporal dynamics of the cortical output. Instead, acoustic processing is altered via a systematic reduction in the driven spike rate output and spectral integration resolution in A1. This study suggests a novel form of plasticity, whereas early postnatal lesions of one sensory cortex can have a functional impact on processing in neighboring sensory cortex.

Perception of Low-Frequency Acoustic Signals by a Harbour Porpoise (<I>Phocoena phocoena</I>) in the Presence of Simulated Offshore Wind Turbine Noise

Using auditory evoked potential (AEP) methods, a study was conducted on a harbour porpoise (Phocoena phocoena) at the Dolfinarium Harderwijk in The Netherlands. The study measured the audible range of wind turbine sounds and their potential masking effects on the acoustic perception of the animal. AEPs were evoked with two types of acoustic stimuli: (1) click-type signals and (2) amplitude-modulated signals. The masking noise resembling the underwater sound emissions of an operational wind turbine was simulated. At first, the animal’s hearing threshold was measured at frequencies between 0.7 and 16 kHz. Subsequently, these measurements were repeated at frequencies between 0.7 and 2.8 kHz in the presence of two different levels of masking noise. The resulting data show a masking effect of the simulated wind turbine sound at 128 dB re 1 µPa at 0.7, 1.0, and 2.0 kHz. This masking effect varied between 4.8 and 7.3 dB at those frequencies. No significant masking was measured at a masking level of 115 dB re 1 µPa. The available data indicate that the potential masking effect would be limited to short ranges in the open sea, but limitations exist to this conclusion and all estimates are based on existing turbine types, not taking into account future developments of larger and potentially noisier turbine types.

Affective and physiological responses to environmental noises and music

Research suggests that respiratory patterns may reflect general dimensions of emotional response. In this study, we investigated the relationships between judgments of affective valence (pleasantness) and arousal and respiratory responses to acoustic stimuli. Sixteen environmental noises and 16 musical fragments of 30 s duration were presented to 31 participants, while respiration, skin conductance level and heart rate were recorded. Judgments of valence and arousal were registered using the 9-point Self-Assessment Manikin. For noises, breathing accelerated and minute ventilation augmented with decreases in pleasantness for low-arousal stimuli and with increases in arousal for positive stimuli. For music, breathing accelerated and minute ventilation augmented with increases both in rated valence and arousal. Skin conductance level increased with arousal ratings for music but not for noises, whereas mean heart rate increased with rated arousal for noises but not for music. Although both noises and music are sound-vibrations, differences in the relationships between affective judgments and physiological responses were found suggesting differences in the processing of the two types of acoustic stimuli.

The importance of breeding vocalizations for mate attraction in a freshwater goby with a composite sound repertoire

Male gobies, Padogobius martensii, emit ‘tonal’ sounds during courtship, and ‘drumming’ and ‘complex’ sounds during spawning. The complex sound is a two-part vocalization consisting of a drumming sound followed without pause by a tonal sound. In the laboratory, the playback of both the tonal sound and the drumming sound to ripe females P. martensii determined oriented approaching and increased the time spent by the subject within the loudspeaker area. Response levels to the sound playback (drumming sounds) tended to be correlated with degree of ripeness of the female. Functional aspects of the female response to both types of acoustic stimuli are discussed.

A neural network architecture for recognizing dolphin acoustic response time and response type.

Bottlenose dolphins (genus Tursiops) were trained in ‘‘choice reaction time’’ experiments to respond to each of two different types of acoustic stimuli by producing the corresponding one of two different vocalizations. An acoustic time history for each stimulus–response pair was obtained by digitizing the voltage output of a nearby hydrophone. To determine response time required that the onset of the response vocalization within the digitized waveform be identified. To distinguish ‘‘correct’’ from ‘‘incorrect’’ responses required that each response waveform be categorized as ‘‘whistle’’ or ‘‘pulsatile.’’ Both determinations were complicated by the presence of background noise and by variability in the characteristics of response vocalizations among the several dolphins. A four-layer feed-forward neural network (using neurons with identity activation functions and unit-gain sigmoidal transfer functions) was developed which achieved a mean error of <1.9 ms in estimating response time and a response-type recognition rate of ≳98% on a test set of one thousand 100-ms vocalization samples from three dolphins, when trained by backpropagation using a training set of two hundred 100-ms vocalization samples from the same dolphins. The performance of this neural network architecture (which can operate at real-time rates) surpasses that previously achieved using offline discriminant analysis (BMDP/PC-90) applied to vocalization samples of much greater (e.g., 700-ms) duration.

Central auditory processing: V. Ear advantages for acoustic stimuli in baboons

Four baboons ( Papio cynocephalus) were tested using food as reward for ear advantages in the monaural discrimination of pure tones, three-tone musical chords, synthetically constructed consonant-vowels, and vowels. All four animals showed highly significant and reproducible ear advantages for each class of acoustic stimulus with marked individual differences in the direction of their ear asymmetry. The results obtained in these experiments represent the first evidence of ear asymmetries for different classes of acoustic stimuli in a nonhuman species. Further, the ear advantages found in these animals under monaural conditions resemble those obtained with dichotic presentation in human subjects and thus suggest that the baboon may be a valuable model of central auditory processing of various types of acoustic stimuli in man.

Masking of Auditory Responses in the Medulla Oblongata of Goldfish

ABSTRACT The nervous activity of single auditory neurones in goldfish brain have been measured. Four types of acoustic stimuli were used, (1) pure tones, (2) noise of one-third octave band width, (3) noise of one-octave band width with centre frequency equal to the pure tone, and (4) white noise. Except for white noise, these stimuli produced the same response to equal sound pressures. The white noise response was less, presumably because the frequency range covered by a single neurone is far narrower than the range of white noise. The conclusion has been reached that for low-frequency acoustic signals, the acoustic power over a frequency band of one to two octaves is integrated by the nervous system. The masking effect of background noise on the acoustic threshold of single units to pure tones is strongest when the noise band has the same centre frequency as the test tone. In this case the tone threshold increases linearly with the background noise level. When the noise band was centred at a different frequency from the tone, the masking effect decreased at a rate of 20–22 dB/octave for the first one-third octave for a tone frequency of 250 Hz. For a tone of 500 Hz the masking effect of lower frequencies was stronger and was reduced by only some 9 dB/octave for the first one-third octave.

The Pattern-Transformation Model of Pitch

This report describes a new approach to pitch perception, based on a kind of auditory pattern recognition. The general approach is formalized in a mathematical model, the “pattern-transformation model.” In the first stage of this model, an acoustic stimulus is assumed to be “transformed” by the sense organ into what is called a neural activity pattern. This pattern is thought to represent roughly the power spectrum of the waveform. Thus, the model is phase insensitive; the temporal fine structure of the stimulus waveform is ignored. The first-stage pattern (power spectrum) is then assumed to be Fourier transformed (neurally) into another pattern of neural activity. This second pattern roughly represents the autocorrelation function of the stimulus. Pitch is derived from the positions of maximal activity in this pattern. From preliminary tests, it appears that the model can accurately predict the pitches of many types of acoustic stimuli. In addition, the model provides numerical estimates of pitch “strength” and “ambiguity.” While experimental confirmation of these predictions is lacking, the strength estimates agree at least qualitatively with available data. [Research supported by a National Science Foundation Postdoctoral Fellowship awarded to the author and the Institute for Perception—TNO, Netherlands.]

Experimental procedures affecting evoked responses recorded from auditory cortex

1. 1. Four pairs of surface to deep-cortex electrodes were implanted in auditory cortex in each of six cats. 2. 2. Electrocorticographic recordings were taken from the electrodes before, during, and after all presentations of two types of acoustic stimuli: a 4 sec train cf clicks at 4000/sec used as the conditioned stimulus (CS) during conditioning, and a single click used as a test signal. For all animals there were at least six experimental sessions before the start ofconditioning sessions; two animals also received pseudo-conditioning sessions. 3. 3. The response evoked from auditory cortex of the unanesthetized preparation by an acoustic stimulus of abrupt onset is composed of a series of potential changes. As recorded in our experiments, the response contained four prominent deflections; a surface positive wave, followed in order by negative, possitive, and negative waves. A method was devised to describe the response by four amplitude measures. 4. 4. The cortical responses evoked by the CS and by the single click were similar in form and magnitude. 5. 5. Systematic changes in the evoked response were observed during the preconditioning sessions. 6. 6. Increases in the evoked response occurred during the pseudo-conditioning sessions. 7. 7. Unless preceded by pseudo-conditioning sessions, the evoked response typically increased during behavioral conditioning, 8. 8. The components of the evoked responses recorded from a given pair of electrodes were not necessarily affected equally by the various experimental procedures. 9. 9. During conditioning, changes in behavior preceded changes in the evoked response. 10. 10. No relation was noted between change in evoked response and particular sub-area of auditory codex in which the electrode was located. 11. 11. Increases in magnitude of the components of the evoked response during the first stages of preconditioning, during pseudo-conditioning, or during conditioning do not appear to be a direct consequence of the conditioning or learning process, that is, the learning of a leg flexion in response to an acoustic stimulus. A more likely interpretation is that the observed changes in the evoked response reflect complex changes in nlany neural structures, the latter changes being related to the emotional state and alertness of the experimental animal.