Changes In Auditory Perception Research Articles

Multimodal acoustic-electric trigeminal nerve stimulation modulates conscious perception

Multimodal stimulation can reverse pathological neural activity and improve symptoms in neuropsychiatric diseases. Recent research shows that multimodal acoustic-electric trigeminal-nerve stimulation (TNS) (i.e., musical stimulation synchronized to electrical stimulation of the trigeminal nerve) can improve consciousness in patients with disorders of consciousness. However, the reliability and mechanism of this novel approach remain largely unknown. We explored the effects of multimodal acoustic-electric TNS in healthy human participants by assessing conscious perception before and after stimulation using behavioral and neural measures in tactile and auditory target-detection tasks. To explore the mechanisms underlying the putative effects of acoustic-electric stimulation, we fitted a biologically plausible neural network model to the neural data using dynamic causal modeling. We observed that (1) acoustic-electric stimulation improves conscious tactile perception without a concomitant change in auditory perception, (2) this improvement is caused by the interplay of the acoustic and electric stimulation rather than any of the unimodal stimulation alone, and (3) the effect of acoustic-electric stimulation on conscious perception correlates with inter-regional connection changes in a recurrent neural processing model. These results provide evidence that acoustic-electric TNS can promote conscious perception. Alterations in inter-regional cortical connections might be the mechanism by which acoustic-electric TNS achieves its consciousness benefits.

Preliminary Perceptual Findings of Singing After Flow Phonation Voice Exercises for Singers in Training

Goals of voice therapy and vocal pedagogy share similar principles and therefore, therapy approaches designed to improve the disordered voice may be equally effective when used to enhance healthy voice and vice versa. The purpose of this study was to investigate the effects of flow phonation voice exercises on vocal characteristics of students in undergraduate vocal music training programs and examine their potential use in vocal pedagogy. A total of 10 cis females were recruited and were randomized into two groups: an experimental group (group 1, n=6) receiving five sessions of flow phonation intervention across 5weeks; and a control group (group 2, n=4) that did not receive any direct intervention other than vocal hygiene education. Participants provided data pertaining to auditory perception, subjective respiratory measures, voice-related quality of life, and vocal fatigue before and after 5weeks. Flow phonation exercises consisted of cup bubble blowing, gargling, and stretch and flow. Wilcoxon signed ranks test was administered to compare outcomes across time points and between groups. Data indicate statistically significant changes in auditory perception of the singing voice, and voice-related quality of life for the group that received flow phonation exercises alone. No other measures showed statistical significance. Overall, this study indicates that the use of flow phonation voice exercises has the potential to improve voice instruction within the voice studio. While our target enrollments were not met to achieve optimal statistical power, our hypotheses were at least partially supported. In particular, positive intervention-related changes were observed in self-perceived voice handicap, and auditory perception of singing which were not observed in the control group.

İşitme Kayıplı Çocuk ve Ergenlerde COVID-19 Pandemisi Etkileri: Ebeveyn Gözünden İşitsel Algı Becerilerinin ve Günlük Rutinlerinin Değişimine Yönelik Tanımlayıcı Bir Çalışma

İşitme Kayıplı Çocuk ve Ergenlerde COVID-19 Pandemisi Etkileri: Ebeveyn Gözünden İşitsel Algı Becerilerinin ve Günlük Rutinlerinin Değişimine Yönelik Tanımlayıcı Bir Çalışma

Ruído Ocupacional, Audição e Qualidade de Vida em Dentistas

ABSTRACT Introduction Workers with excessive noise exposure can develop problems related to general health, hearing and have changes in quality of life, with Noise-Induced Hearing Loss (NIHL) being the most common change associated with hearing. Dentists, when using different types of equipment for clinical and surgical procedures, end up being exposed to noise daily. Hearing loss is associated with decreased life quality, including an increased risk of loneliness, isolation and a decline in functional fitness. Considering that hearing is fundamental in the socialization process and, consequently, for oral communication, any and all changes in auditory perception can trigger problems in social interaction with a negative impact on people’s lives. Objective To analyse the impact of noise on hearing and life quality of dentists in Paraná. Methods This is a descriptive observational, cross-sectional study carried out with forty dentists from southern Brazil. The research subjects underwent basic audiological evaluation and high frequency audiometry, in addition to answering two questionnaires, one about life quality (SF-36) and the other with data about the working conditions, knowledge and perceptions of dentists regarding the exposure to noise at work. Results Auditory changes suggestive of being induced by noise were observed in 15% of dentists. In high frequency audiometry, auditory alterations occurred in six professionals, and in four of them there was bilateral alteration. The SF-36 indicated median values of 62.57 for general health and 64 for vitality; 100 being the maximum score. It was found that 52.5% of dentists are aware of the effects of noise exposure on health, but only 5% declared using ear protectors during the exercise of their profession. Conclusion Early awareness of the effects of noise would bring more comfort and life quality to dentists, as well as less hearing problems.

Auditory fear conditioning alters neural gain in the cochlear nucleus: a wireless neural recording study in freely behaving rats.

Anxiety disorders involve distorted perception of the world including increased saliency of stress-associated cues. However, plasticity in the initial sensory regions of the brain following a fearful experience has never been examined. The cochlear nucleus (CN) is the first station in the central auditory system, with heterogeneous collections of neurons that not only project to but also receive projections from cortico-limbic regions, suggesting a potential for experience-dependent plasticity. Using wireless neural recordings in freely behaving rats, we demonstrate for the first time that neural gain in the CN is significantly altered by fear conditioning to auditory sequences. Specifically, the ventral subnuclei significantly increased firing rate to the conditioned tone sequence, while the dorsal subnuclei significantly decreased firing rate during the conditioning session overall. These findings suggest subregion-specific changes in the balance of inhibition and excitation in the CN as a result of conditioning experience. Heart rate was measured as the conditioned response (CR), which showed that while pre-conditioned stimulus (CS) responding did not change across baseline and conditioning sessions, significant changes in heart rate were observed to the tone sequence followed by shock. Heart-rate findings support acquisition of conditioned fear. Taken together, the present study presents first evidence for potential experience-dependent changes in auditory perception that involve novel plasticity within the first site of processing auditory information in the brain.

Supra-threshold changes in auditory perception associated with sensorineural hearing loss

Supra-threshold changes in auditory perception associated with sensorineural hearing loss

Neural Basis of Sensorimotor Plasticity in Speech Motor Adaptation.

When we speak, we get correlated sensory feedback from speech sounds and from the muscles and soft tissues of the vocal tract. Here we dissociate the contributions of auditory and somatosensory feedback to identify brain networks that underlie the somatic contribution to speech motor learning. The technique uses a robotic device that selectively alters somatosensory inputs in combination with resting-state fMRI scans that reveal learning-related changes in functional connectivity. A partial correlation analysis is used to identify connectivity changes that are not explained by the time course of activity in any other learning-related areas. This analysis revealed changes related to behavioral improvements in movement and separately, to changes in auditory perception: Speech motor adaptation itself was associated with connectivity changes that were primarily in non-motor areas of brain, specifically, to a strengthening of connectivity between auditory and somatosensory cortex and between presupplementary motor area and the inferior parietal lobule. In contrast, connectively changes associated with alterations to auditory perception were restricted to speech motor areas, specifically, primary motor cortex and inferior frontal gyrus. Overall, our findings show that during adaptation, somatosensory inputs result in a broad range of changes in connectivity in areas associated with speech motor control and learning.

Longitudinal Changes in Electrically Evoked Auditory Event-Related Potentials in Children With Auditory Brainstem Implants: Preliminary Results Recorded Over 3 Years.

This preliminary study aimed (1) to assess longitudinal changes in electrically evoked auditory event-related potentials (eERPs) in children with auditory brainstem implants (ABIs) and (2) to explore whether these changes could be accounted for by maturation in the central auditory system of these patients. Study participants included 5 children (S1 to S5) with an ABI in the affected ear. The stimulus was a train of electrical pulses delivered to individual ABI electrodes via a research interface. For each subject, the eERP was repeatedly measured in multiple test sessions scheduled over up to 41 months after initial device activation. Longitudinal changes in eERPs recorded for each ABI electrode were evaluated using intraclass correlation tests for each subject. eERPs recorded in S1 showed notable morphological changes for five ABI electrodes over 41 months. In parallel, signs or symptoms of nonauditory stimulation elicited by these electrodes were observed or reported at 41 months. eERPs could not be observed in S2 after 9 months of ABI use but were recorded at 12 months after initial stimulation. Repeatable eERPs were recorded in S3 in the first 9 months. However, these responses were either absent or showed remarkable morphological changes at 30 months. Longitudinal changes in eERP waveform morphology recorded in S4 and S5 were also observed. eERP responses in children with ABIs could change over a long period of time. Maturation of the central auditory system could not fully account for these observed changes. Children with ABIs need to be closely monitored for potential changes in auditory perception and unfavorable nonauditory sensations. Neuroimaging correlates are needed to better understand the emergence of nonauditory stimulation over time in these children.

Face configuration affects speech perception: Evidence from a McGurk mismatch negativity study

We perceive identity, expression and speech from faces. While perception of identity and expression depends crucially on the configuration of facial features it is less clear whether this holds for visual speech perception.Facial configuration is poorly perceived for upside-down faces as demonstrated by the Thatcher illusion in which the orientation of the eyes and mouth with respect to the face is inverted (Thatcherization). This gives the face a grotesque appearance but this is only seen when the face is upright.Thatcherization can likewise disrupt visual speech perception but only when the face is upright indicating that facial configuration can be important for visual speech perception. This effect can propagate to auditory speech perception through audiovisual integration so that Thatcherization disrupts the McGurk illusion in which visual speech perception alters perception of an incongruent acoustic phoneme. This is known as the McThatcher effect.Here we show that the McThatcher effect is reflected in the McGurk mismatch negativity (MMN). The MMN is an event-related potential elicited by a change in auditory perception. The McGurk-MMN can be elicited by a change in auditory perception due to the McGurk illusion without any change in the acoustic stimulus.We found that Thatcherization disrupted a strong McGurk illusion and a correspondingly strong McGurk-MMN only for upright faces. This confirms that facial configuration can be important for audiovisual speech perception. For inverted faces we found a weaker McGurk illusion but, surprisingly, no MMN. We also found no correlation between the strength of the McGurk illusion and the amplitude of the McGurk-MMN. We suggest that this may be due to a threshold effect so that a strong McGurk illusion is required to elicit the McGurk-MMN.

Plasticity in the Human Speech Motor System Drives Changes in Speech Perception

Recent studies of human speech motor learning suggest that learning is accompanied by changes in auditory perception. But what drives the perceptual change? Is it a consequence of changes in the motor system? Or is it a result of sensory inflow during learning? Here, subjects participated in a speech motor-learning task involving adaptation to altered auditory feedback and they were subsequently tested for perceptual change. In two separate experiments, involving two different auditory perceptual continua, we show that changes in the speech motor system that accompany learning drive changes in auditory speech perception. Specifically, we obtained changes in speech perception when adaptation to altered auditory feedback led to speech production that fell into the phonetic range of the speech perceptual tests. However, a similar change in perception was not observed when the auditory feedback that subjects' received during learning fell into the phonetic range of the perceptual tests. This indicates that the central motor outflow associated with vocal sensorimotor adaptation drives changes to the perceptual classification of speech sounds.

What is the McGurk effect?

What is the McGurk effect?

Temporal and non-temporal processes in the elderly

The present study examined whether the reported age-related decline in auditory temporal resolution is specific to the temporal domain or rather reflects a general decline in auditory perception, including the stimulus intensity domain. The performance of 89 healthy participants aged between 21 and 82 years with normal hearing was tested on a variety of psychophysical tasks, where discrimination was based either on the temporal or on the intensity domains. Stimulus levels for all tasks were 40 dB SL (corrected for threshold). Participants were also tested on two cognitive tasks: Wechsler Adult Intelligence Scale, Third Edition, matrices and digit span. Findings indicate that age was significantly negatively correlated with performance on three of the temporal resolution tasks, namely, dichotic temporal-order judgment, spectral temporal-order judgment, and gap detection, but not on the intensity discrimination task, thus emphasizing the specificity of the age-related decline to the auditory temporal domain. The overall results suggest that age-related changes in auditory perception are specific to the temporal domain, even when controlling for hearing sensitivity and cognitive ability, and are not reflected in other aspects of non-temporal perception, such as intensity discrimination.

Lachgas-Sauerstoff-Inhalation zur Analgesie in der ästhetischen Dermatologie

Local anaesthesia often is insufficient for more extensive procedures. Instead of general anaesthesia or sedation, pediatricians, gynaecologists and dentists increasingly use nitrous oxide (N2O). This study evaluates the suitability of this form of anesthesia in dermatology. In 24 patients (18 w, 6 m, mean age 49 y.) N2O/O2 inhalation (Livopan®) was used during 46 procedures with indications including fractional RF/wrinkle reduction, IPL/rosacea, q-sw. laser/tattoos and hemosiderosis as well as fractional Er:Glass laser for scars and hypopigmentation. In 26 procedures subjective pain intensity was measured (visual analogue scale 0-10). With N2O the treatment pain was lowered from 6.6 ± 1.6 to 2.9 ± 1.7 (median, p = 0.000). 23/24 patients chose N2O for their next treatment. Beside euphoria, fatigue, slight drowsiness, dizziness, nausea or change in auditory perception, no other side effects occurred. The pronounced analgesia, the easy self-administration, the fast onset and complete recovery after a few minutes and the low ratio of side effects make the N2O/O2 inhalation to an ideal addendum in the management of larger painful procedures in dermatology as long as contraindications and safety precautions are respected.

Resultados da reabilitação auditiva em idosos usuários de próteses auditivas avaliados com teste dicótico

To verify the effects of auditory rehabilitation through the analysis of quantitative and qualitative aspects of the Staggered Spondaic Word Test (SSW) in elderly people who have recently started wearing hearing aids. The study included 17 elderly people, who have recently started wearing hearing aids, aged between 60 and 84 years old, divided into two groups: G1, for those who only wore hearing aids, and G2, for those submitted to an auditory rehabilitation program structured in seven sessions, including auditory counseling and training. All subjects were evaluated with the SSW test at two different moments, the beginning and the end of the study. All data were statistically analyzed. Regarding quantitative aspects, subjects in G1 showed improvements, but no statistically significant differences were observed between evaluations, while G2 presented statistically significant improvements on the competitive right, the non-competitive left and the total number of hits. When comparing the final performance of both groups, there were statistically significant differences concerning almost all of the variables with greater results to the G2 group. Regarding qualitative aspects, volunteers in both groups had difficulties with phonemic decoding, gradual memory loss, organization and integration in both assessments, with different alterations between them. The scores obtained by subjects in G2 submitted to the hearing rehabilitation in the variables competitive right and left non-competitive show especially the improvement on the left hemisphere, due to auditory training. For further evidence of differences between the results of qualitative aspects, a longer period of time would possibly be required in order for changes in auditory perception to occur associated with other sensory functions.

Auditory grouping mechanisms reflect a sound's relative position in a sequence

The human brain uses acoustic cues to decompose complex auditory scenes into its components. For instance to improve communication, a listener can select an individual “stream,” such as a talker in a crowded room, based on cues such as pitch or location. Despite numerous investigations into auditory streaming, few have demonstrated clear correlates of perception; instead, in many studies perception covaries with changes in physical stimulus properties (e.g., frequency separation). In the current report, we employ a classic ABA streaming paradigm and human electroencephalography (EEG) to disentangle the individual contributions of stimulus properties from changes in auditory perception. We find that changes in perceptual state—that is the perception of one versus two auditory streams with physically identical stimuli—and changes in physical stimulus properties are reflected independently in the event-related potential (ERP) during overlapping time windows. These findings emphasize the necessity of controlling for stimulus properties when studying perceptual effects of streaming. Furthermore, the independence of the perceptual effect from stimulus properties suggests the neural correlates of streaming reflect a tone's relative position within a larger sequence (1st, 2nd, 3rd) rather than its acoustics. By clarifying the role of stimulus attributes along with perceptual changes, this study helps explain precisely how the brain is able to distinguish a sound source of interest in an auditory scene.

Taking advantage of behavioral changes during development and training to assess sensory coding mechanisms

The relationship between behavioral and neural performance has been explored in adult animals, but rarely during the developmental period when perceptual abilities emerge. We used these naturally occurring changes in auditory perception to evaluate underlying encoding mechanisms. Performance of juvenile and adult gerbils on an amplitude modulation (AM) detection task was compared with response properties from auditory cortex of age-matched animals. When tested with an identical behavioral procedure, juveniles display poorer AM detection thresholds than adults. Two neurometric analyses indicate that the most sensitive juvenile and adult neurons have equivalent AM thresholds. However, a pooling neurometric revealed that adult cortex encodes smaller AM depths. By each measure, neural sensitivity was superior to psychometric thresholds. However, juvenile training improved adult behavioral thresholds, such that they verged on the best sensitivity of adult neurons. Thus, periods of training may allow an animal to use the encoded information already present in cortex.

Finding the Pitch of the Missing Fundamental in Infants

Pitch perception is critical for the perception of speech and music, for object identification, and for auditory scene analysis, whereby representations are derived for each sounding object in the environment from the complex sound wave that reaches the ears. The perceived pitch of a complex sound corresponds to its fundamental frequency. However, removal of energy at the fundamental does not alter the pitch because adults use the harmonics to derive the pitch (Bendor and Wang, 2005; Trainor, 2008). Although sound frequency is represented subcortically, the integration of harmonics into a representation of pitch does not occur until auditory cortex (Bendor and Wang, 2005). Given that auditory cortex is immature in young infants, we examined the development of cortical representations for pitch by measuring electrophysiological (EEG) responses to pitch changes that required processing the pitch of the missing fundamental. Adults and infants 4 months and older showed a mismatch negativity response to these pitch changes, but 3-month-old infants did not. Thus, cortical representations of the pitch of the missing fundamental emerge between 3 and 4 months of age, indicating that there is a profound change in auditory perception for pitch in early infancy.

Midlatency auditory-evoked potentials in the assessment of sedation in cardiac surgery patients

Objectives: Midlatency auditory-evoked potentials (MLAEPs) may provide an objective measure of depth of sedation. The aim of this study was to evaluate MLAEPs for measuring sedation in cardiac surgery patients. Design: Prospective study. Setting: Intensive care unit of a university hospital. Participants: Twenty-two patients scheduled for elective coronary artery bypass grafting. Interventions: MLAEPs were obtained at 5 time points: the day before surgery (baseline), 1 hour before surgery, after premedication, postoperatively during deep (Ramsay 6) and moderate (Ramsay 4) sedation, and the day after surgery. Measurements and Main Results: The latency of the Nb MLAEP component increased from 44 ms (38–60 ms; median, range) at baseline to 49 ms (41–64 ms) after premedication ( p = 0.03) and further to 63 ms (48–80 ms) during deep sedation after surgery ( P < 0.01). Although a decreasing clinical level of sedation after rewarming was not associated with a significant change in Nb latency (61 ms [42–78 ms]), the MLAEP NaPa amplitude increased from 0.9 μV (0.4–1.6 μV) to 1.3 μV (0.8–3.9 μV; p = 0.01). Nb latency remained increased the day after surgery (49 ms [37–71 ms]) as compared with baseline ( p < 0.01). Conclusions: MLAEP latencies can reflect subtle changes in auditory perception, while amplitudes seem to change with transition between deep levels of sedation.

Auditory perception and speech identification in children with cochlear implants tested with the EARS protocol.

The performance of children who receive a cochlear implant may be dependent on both age of the child at implantation and the amount of experience with the implant. In the present study, changes in auditory perception and speech identification were investigated with experience of 71 children who had received a cochlear implant. The children were divided into three groups, those above and those below the age of 7 years at the time of implantation, and those aged 3 years or younger deafened by meningitis. The children received either the Nucleus 22, the Nucleus 24 or the Med El C40+ implant. The test material was a reduced form of the EARS evaluation protocol developed by Med El into a multi-language format. Tests were performed pre-operatively, within 2-5 days of first fitting of the speech processor, then at 1, 3 and 6 months and every 6 months thereafter, for a total period of 24 months. The results indicated that all children showed improvement after 6-12 months. The rate of improvement differed between age groups. Children over 7 years of age had pre-operatively higher test scores than younger children, presumably because of their previous experience with hearing aids. These children showed an immediate post-operative drop in performance that recovered 1-3 months later. The children aged under 7 years started at lower performance levels but approached those of the older children after 12 months' cochlear implant use because their post-operative drop was less significant and their performance improved faster. Children who had been deafened by meningitis and implanted at the age of 3 or less made little progress over the first 6 months but approached test levels of the under-7-year-olds by 18 months or later. All three components of the evaluation protocol employed the Listening Progress Profile (LiP), the Monosyllabic-Trochee-Polysyllabic Test (MTP) and the Meaningful Auditory Integration Scale (MAIS) and proved to be valuable in demonstrating improvement in performance of cochlear implant children in all age groups once the immediate post-operative drop had been overcome.

Stapes surgery and psychiatric complications

Changes in auditory perception can cause disturbances in development and personality. This phenomenon has been studied in particular in children hearing loss or in progressive or sudden hearing loss in the adult. We present the case of a patient with psychobehavioural alterations after restoration of hearing following a small fenestra stapedectomy for bilateral otosclerosis with moderate–severe hearing impairment. The diagnosis, physiopathology and medicolegal implications are discussed.