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1.
J Assoc Res Otolaryngol ; 25(2): 131-147, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38334887

RESUMO

PURPOSE: This systematic review aims to assess the impact of sensorineural hearing loss (SNHL) on various frequency-following response (FFR) parameters. METHODS: Following PRISMA guidelines, a systematic review was conducted using PubMed, Web of Science, and Scopus databases up to January 2023. Studies evaluating FFRs in patients with SNHL and normal hearing controls were included. RESULTS: Sixteen case-control studies were included, revealing variability in acquisition parameters. In the time domain, patients with SNHL exhibited prolonged latencies. The specific waves that were prolonged differed across studies. There was no consensus regarding wave amplitude in the time domain. In the frequency domain, focusing on studies that elicited FFRs with stimuli of 170 ms or longer, participants with SNHL displayed a significantly smaller fundamental frequency (F0). Results regarding changes in the temporal fine structure (TFS) were inconsistent. CONCLUSION: Patients with SNHL may require more time for processing (speech) stimuli, reflected in prolonged latencies. However, the exact timing of this delay remains unclear. Additionally, when presenting longer stimuli (≥ 170 ms), patients with SNHL show difficulties tracking the F0 of (speech) stimuli. No definite conclusions could be drawn on changes in wave amplitude in the time domain and the TFS in the frequency domain. Patient characteristics, acquisition parameters, and FFR outcome parameters differed greatly across studies. Future studies should be performed in larger and carefully matched subject groups, using longer stimuli presented at the same intensity in dB HL for both groups, or at a carefully determined maximum comfortable loudness level.


Assuntos
Perda Auditiva Neurossensorial , Percepção da Fala , Humanos , Percepção da Fala/fisiologia , Estudos de Casos e Controles , Fala
2.
Psychophysiology ; 61(2): e14450, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37779371

RESUMO

There are sounds that most people perceive as highly unpleasant, for instance, the sound of rubbing pieces of polystyrene together. Previous research showed larger physiological and neural responses for such aversive compared to neutral sounds. Hitherto, it remains unclear whether habituation, i.e., diminished responses to repeated stimulus presentation, which is typically reported for neutral sounds, occurs to the same extent for aversive stimuli. We measured the mismatch negativity (MMN) in response to rare occurrences of aversive or neutral deviant sounds within an auditory oddball sequence in 24 healthy participants, while they performed a demanding visual distractor task. Deviants occurred as single events (i.e., between two standards) or as double deviants (i.e., repeating the identical deviant sound in two consecutive trials). All deviants elicited a clear MMN, and amplitudes were larger for aversive than for neutral deviants (irrespective of their position within a deviant pair). This supports the claim of preattentive emotion evaluation during early auditory processing. In contrast to our expectations, MMN amplitudes did not show habituation, but increased in response to deviant repetition-similarly for aversive and neutral deviants. A more fine-grained analysis of individual MMN amplitudes in relation to individual arousal and valence ratings of each sound item revealed that stimulus-specific MMN amplitudes were best predicted by the interaction of deviant position and perceived arousal, but not by valence. Deviants with perceived higher arousal elicited larger MMN amplitudes only at the first deviant position, indicating that the MMN reflects preattentive processing of the emotional content of sounds.


Assuntos
Eletroencefalografia , Potenciais Evocados Auditivos , Humanos , Potenciais Evocados Auditivos/fisiologia , Habituação Psicofisiológica , Percepção Auditiva/fisiologia , Som , Estimulação Acústica
4.
J Speech Lang Hear Res ; 66(12): 4785-4800, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37944057

RESUMO

PURPOSE: The aim of the present study is to characterize the maturational changes during the first 6 months of life in the neural encoding of two speech sound features relevant for early language acquisition: the stimulus fundamental frequency (fo), related to stimulus pitch, and the vowel formant composition, particularly F1. The frequency-following response (FFR) was used as a snapshot into the neural encoding of these two stimulus attributes. METHOD: FFRs to a consonant-vowel stimulus /da/ were retrieved from electroencephalographic recordings in a sample of 80 healthy infants (45 at birth and 35 at the age of 1 month). Thirty-two infants (16 recorded at birth and 16 recorded at 1 month) returned for a second recording at 6 months of age. RESULTS: Stimulus fo and F1 encoding showed improvements from birth to 6 months of age. Most remarkably, a significant improvement in the F1 neural encoding was observed during the first month of life. CONCLUSION: Our results highlight the rapid and sustained maturation of the basic neural machinery necessary for the phoneme discrimination ability during the first 6 months of age.


Assuntos
Percepção da Fala , Recém-Nascido , Lactente , Humanos , Percepção da Fala/fisiologia , Desenvolvimento da Linguagem , Fonética , Eletroencefalografia
5.
Front Psychol ; 14: 1188567, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37794915

RESUMO

The major goal of psychoarchaeoacoustics is to understand the psychology behind motivations and emotions of past communities when selecting certain acoustic environments to set activities involving the production of paintings and carvings. Within this framework, the present study seeks to explore whether a group of archaeological rock art sites in Altai (Siberia, Russia) are distinguished by particular acoustic imprints that elicit distinct reactions on listeners, in perceptual and emotional terms. Sixty participants were presented with a series of natural sounds convolved with six impulse responses from Altai, three of them recorded in locations in front of rock art panels and three of them in front of similar locations but without any trace of rock art. Participants were interrogated about their subjective perception of the sounds presented, using 10 psychoacoustic and emotional scales. The mixed ANOVA analyses carried out revealed that feelings of "presence," "closeness," and "tension" evoked by all sounds were significantly influenced by the location. These effects were attributed to the differences in reverberation between the locations with and without rock art. Despite results are not consistent across all the studied rock art sites, and acknowledging the presence of several limitations, this study highlights the significance of its methodology. It stresses the crucial aspect of incorporating the limitations encountered in shaping future research endeavors.

6.
Ear Hear ; 44(4): 829-841, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36759954

RESUMO

OBJECTIVES: The present envelope frequency-following response (FFR ENV ) study aimed at characterizing the neural encoding of the fundamental frequency of speech sounds in neonates born at the higher end of the birth weight continuum (>90th percentile), known as large-for-gestational age (LGA). DESIGN: Twenty-five LGA newborns were recruited from the maternity unit of Sant Joan de Déu Barcelona Children's Hospital and paired by age and sex with 25 babies born adequate-for-gestational age (AGA), all from healthy mothers and normal pregnancies. FFR ENV s were elicited to the/da/ syllable and recorded while the baby was sleeping in its cradle after a successful universal hearing screening. Neural encoding of the stimulus' envelope of the fundamental frequency (F 0ENV ) was characterized through the FFR ENV spectral amplitude. Relationships between electrophysiological parameters and maternal/neonatal variables that may condition neonatal neurodevelopment were assessed, including pregestational body mass index (BMI), maternal gestational weight gain and neonatal BMI. RESULTS: LGA newborns showed smaller spectral amplitudes at the F 0ENV compared to the AGA group. Significant negative correlations were found between neonatal BMI and the spectral amplitude at the F 0ENV . CONCLUSIONS: Our results indicate that in spite of having a healthy pregnancy, LGA neonates' central auditory system is impaired in encoding a fundamental aspect of the speech sounds, namely their fundamental frequency. The negative correlation between the neonates' BMI and FFR ENV indicates that this impaired encoding is independent of the pregnant woman BMI and weight gain during pregnancy, supporting the role of the neonatal BMI. We suggest that the higher adipose tissue observed in the LGA group may impair, via proinflammatory products, the fine-grained central auditory system microstructure required for the neural encoding of the fundamental frequency of speech sounds.


Assuntos
Macrossomia Fetal , Doenças do Recém-Nascido , Lactente , Criança , Gravidez , Recém-Nascido , Humanos , Feminino , Idade Gestacional , Fala , Peso ao Nascer , Índice de Massa Corporal
7.
Dev Sci ; 26(5): e13362, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36550689

RESUMO

Fetal hearing experiences shape the linguistic and musical preferences of neonates. From the very first moment after birth, newborns prefer their native language, recognize their mother's voice, and show a greater responsiveness to lullabies presented during pregnancy. Yet, the neural underpinnings of this experience inducing plasticity have remained elusive. Here we recorded the frequency-following response (FFR), an auditory evoked potential elicited to periodic complex sounds, to show that prenatal music exposure is associated to enhanced neural encoding of speech stimuli periodicity, which relates to the perceptual experience of pitch. FFRs were recorded in a sample of 60 healthy neonates born at term and aged 12-72 hours. The sample was divided into two groups according to their prenatal musical exposure (29 daily musically exposed; 31 not-daily musically exposed). Prenatal exposure was assessed retrospectively by a questionnaire in which mothers reported how often they sang or listened to music through loudspeakers during the last trimester of pregnancy. The FFR was recorded to either a /da/ or an /oa/ speech-syllable stimulus. Analyses were centered on stimuli sections of identical duration (113 ms) and fundamental frequency (F0  = 113 Hz). Neural encoding of stimuli periodicity was quantified as the FFR spectral amplitude at the stimulus F0 . Data revealed that newborns exposed daily to music exhibit larger spectral amplitudes at F0 as compared to not-daily musically-exposed newborns, regardless of the eliciting stimulus. Our results suggest that prenatal music exposure facilitates the tuning to human speech fundamental frequency, which may support early language processing and acquisition. RESEARCH HIGHLIGHTS: Frequency-following responses to speech were collected from a sample of neonates prenatally exposed to music daily and compared to neonates not-daily exposed to music. Neonates who experienced daily prenatal music exposure exhibit enhanced frequency-following responses to the periodicity of speech sounds. Prenatal music exposure is associated with a fine-tuned encoding of human speech fundamental frequency, which may facilitate early language processing and acquisition.


Assuntos
Música , Percepção da Fala , Humanos , Recém-Nascido , Fala , Percepção da Fala/fisiologia , Estudos Retrospectivos , Percepção Auditiva/fisiologia , Estimulação Acústica/métodos
8.
Semin Hear ; 43(3): 162-176, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36313048

RESUMO

The frequency-following response (FFR) to periodic complex sounds is a noninvasive scalp-recorded auditory evoked potential that reflects synchronous phase-locked neural activity to the spectrotemporal components of the acoustic signal along the ascending auditory hierarchy. The FFR has gained recent interest in the fields of audiology and auditory cognitive neuroscience, as it has great potential to answer both basic and applied questions about processes involved in sound encoding, language development, and communication. Specifically, it has become a promising tool in neonates, as its study may allow both early identification of future language disorders and the opportunity to leverage brain plasticity during the first 2 years of life, as well as enable early interventions to prevent and/or ameliorate sound and language encoding disorders. Throughout the present review, we summarize the state of the art of the neonatal FFR and, based on our own extensive experience, present methodological approaches to record it in a clinical environment. Overall, the present review is the first one that comprehensively focuses on the neonatal FFRs applications, thus supporting the feasibility to record the FFR during the first days of life and the predictive potential of the neonatal FFR on detecting short- and long-term language abilities and disruptions.

9.
Front Psychol ; 13: 844029, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360627

RESUMO

In western cultures, when it comes to places of worship and liturgies, music, acoustics and architecture go hand in hand. In the present study, we aimed to investigate whether the emotions evoked by music are enhanced by the acoustics of the space where the music was composed to be played on. We explored whether the emotional responses of western naïve listeners to two vocal pieces from the Renaissance, one liturgical and one secular, convolved with the impulse responses of four Christian temples from the United Kingdom, were modulated by the appropriate piece/space matching. In an alternative forced choice task where participants had to indicate their preference for the original recording of the piece (not convolved with any temple-like acoustics) vs. the convolved one, no significant differences were found. However, in the tasks where participants rated their emotional in response to each piece and acoustic condition, the factorial ANCOVA analyses performed on the results revealed significant effects. We observed that, across pieces and spaces, participants found the temple-like acoustics as more transcendent, compared to the acoustics of the original version of the pieces. In addition, they rated the secular piece as more tender and the liturgical piece as more expressive in its original versions, compared to the convolved ones. We conclude that the acoustic signature of the four Christian temples causes an exaltation of certain emotions on listeners, although this effect is not associated to one or another musical piece.

10.
Cortex ; 148: 1-13, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35063842

RESUMO

Adaptation to the sensory environment is essential in everyday life, to anticipate future events and quickly detect and respond to changes; and to distinguish vocal variations in congeners, for communication. The aim of the current study was to explore the effects of the nature (vocal/non-vocal) of the information to be encoded, on the establishment of auditory regularities. In electrophysiology, neural adaptation is measured by the 'Repetition Positivity' (RP), which refers to an increase in positive potential, with the increasing number of repetitions of a same stimulus. The RP results from the combined variation of several ERP components; the P1, the first positivity (∼100 ms) may reflect the onset of repetition effects. We recorded auditory evoked potentials during a roving paradigm in which trains of 4, 8 or 16 repetitions of the same stimulus were presented. Sequences of vocal and non-vocal complex stimuli were delivered, to study the influence of the type of stimulation on the characteristics of the brain responses. The P1 to each train length, and the RP responses were recorded between 90 and 200 ms, reflecting adaptation for both vocal and non-vocal stimuli. RP was not different between vocal and non-vocal sequences (in latency, amplitude and spatial organization) and was found to be similar to that found in previous studies using pure tones, suggesting that the repetition suppression phenomena is somehow independent of the nature of the stimulus. However, results showed faster stabilization of the P1 amplitude for non-vocal stimuli than for vocal stimuli, which require more repetitions. This revealed different dynamics for the establishment of regularity encoding for non-vocal and vocal stimuli, indicating that the richness of vocal sounds may require further processing before full neural adaptation occurs.


Assuntos
Eletroencefalografia , Voz , Estimulação Acústica/métodos , Adaptação Fisiológica , Eletroencefalografia/métodos , Potenciais Evocados Auditivos/fisiologia , Humanos
11.
Dev Sci ; 25(3): e13189, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34758093

RESUMO

Infants born after fetal growth restriction (FGR)-an obstetric condition defined as the failure to achieve the genetic growth potential-are prone to neurodevelopmental delays, with language being one of the major affected areas. Yet, while verbal comprehension and expressive language impairments have been observed in FGR infants, children and even adults, specific related impairments at birth, such as in the ability to encode the sounds of speech, necessary for language acquisition, remain to be disclosed. Here, we used the frequency-following response (FFR), a brain potential correlate of the neural phase locking to complex auditory stimuli, to explore the encoding of speech sounds in FGR neonates. Fifty-three neonates born with FGR and 48 controls born with weight adequate-for-gestational age (AGA) were recruited. The FFR was recorded to the consonant-vowel stimulus (/da/) during sleep and quantified as the spectral amplitude to the fundamental frequency of the syllable and its signal-to-noise ratio (SNR). The outcome was available in 45 AGA and 51 FGR neonates, yielding no differences for spectral amplitudes. However, SNR was strongly attenuated in the FGR group compared to the AGA group at the vowel region of the stimulus. These findings suggest that FGR population present a deficit in the neural pitch tracking of speech sounds already present at birth. Our results pave the way for future research on the potential clinical use of the FFR in this population, so that if confirmed, a disrupted FFR recorded at birth may help deriving FGR neonates at risk for postnatal follow-ups.


Assuntos
Fonética , Percepção da Fala , Adulto , Criança , Feminino , Retardo do Crescimento Fetal , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Gravidez , Fala , Percepção da Fala/fisiologia
12.
Front Hum Neurosci ; 15: 734200, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650417

RESUMO

Electrophysiological sensory deviance detection signals, such as the mismatch negativity (MMN), have been interpreted from the predictive coding framework as manifestations of prediction error (PE). From a frequentist perspective of the classic oddball paradigm, deviant stimuli are unexpected because of their low probability. However, the amount of PE elicited by a stimulus can be dissociated from its probability of occurrence: when the observer cannot make confident predictions, any event holds little surprise value, no matter how improbable. Here we tested the hypothesis that the magnitude of the neural response elicited to an improbable sound (D) would scale with the precision of the prediction derived from the repetition of another sound (S), by manipulating repetition stability. We recorded the Electroencephalogram (EEG) from 20 participants while passively listening to 4 types of isochronous pure tone sequences differing in the probability of the S tone (880 Hz) while holding constant the probability of the D tone [1,046 Hz; p(D) = 1/11]: Oddball [p(S) = 10/11]; High confidence (7/11); Low confidence (4/11); and Random (1/11). Tones of 9 different frequencies were equiprobably presented as fillers [p(S) + p(D) + p(F) = 1]. Using a mass-univariate non-parametric, cluster-based correlation analysis controlling for multiple comparisons, we found that the amplitude of the deviant-elicited ERP became more negative with increasing S probability, in a time-electrode window consistent with the MMN (ca. 120-200 ms; frontal), suggesting that the strength of a PE elicited to an improbable event indeed increases with the precision of the predictive model.

13.
Neurobiol Aging ; 108: 1-15, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34464912

RESUMO

Speech comprehension deficits constitute a major issue for an increasingly aged population, as they may lead older individuals to social isolation. Since conversation requires constant monitoring, updating and selecting information, auditory working memory decline, rather than impoverished hearing acuity, has been suggested a core factor. However, in stark contrast to the visual domain, the neurophysiological mechanisms underlying auditory working memory deficits in healthy aging remain poorly understood, especially those related to on-the-fly information processing under increasing load. Therefore, we investigated the behavioral costs and electrophysiological differences associated with healthy aging and working memory load during continuous auditory processing. We recorded EEG activity from 27 younger (∼25 years) and 29 older (∼70 years) participants during their performance on an auditory version of the n-back task with speech syllables and 2 workload levels (1-back; 2-back). Behavioral measures were analyzed as indices of function; event-related potentials as proxies for sensory and cognitive processes; and theta oscillatory power as a reflection of memory and central executive function. Our results show age-related differences in auditory information processing within a latency range that is consistent with a series of impaired functions, from sensory gating to cognitive resource allocation during constant information updating, especially under high load.


Assuntos
Percepção Auditiva/fisiologia , Eletroencefalografia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Envelhecimento Saudável/fisiologia , Envelhecimento Saudável/psicologia , Memória de Curto Prazo/fisiologia , Idoso , Feminino , Humanos , Masculino , Fala/fisiologia , Adulto Jovem
14.
J Speech Lang Hear Res ; 64(6): 2085-2102, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34057846

RESUMO

Purpose The purpose of this study is to characterize parameters used for frequency-following response (FFR) acquisition in children up to 24 months of age through a systematic review. Method The study was registered in PROSPERO and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses' recommendations. Search was performed in six databases (LILACS, LIVIVO, PsycINFO, PubMed, Scopus, and Web of Science) and gray literature (Google Scholar, OpenGrey, ProQuest)as well as via manual searches in bibliographic references. Observational studies using speech stimuli to elicit the FFR in infants with normal hearing on the age range from 0 until 24 months were included. No restrictions regarding language and year of publication were applied. Risk of bias was assessed with the Joanna Briggs Institute Critical Appraisal Checklist. Data on stimulus, presentation rate, time window for analysis, number of sweeps, artifact rejection, online filters, stimulated ear, and examination condition were extracted. Results Four hundred fifty-nine studies were identified. After removing duplicates and reading titles and abstracts, 15 articles were included. Seven studies were classified as low risk of bias, seven as moderate risk, and one as high risk. Conclusions There is a consensus in the use of some acquisition parameters of the FFR with speech stimulus, such as the vertical mounting, the use of alternating polarity, a sampling rate of 20000 Hz, and the /da/ synthesized syllable of 40 ms in duration as the preferred stimulus. Although these parameters show some consensus, the results disclosed lack of a single established protocol for FFR acquisition with speech stimulus in infants in the investigated age range.


Assuntos
Fala , Criança , Humanos , Lactente , Recém-Nascido
15.
Sci Rep ; 11(1): 9715, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33958663

RESUMO

Does language categorization influence face identification? The present study addressed this question by means of two experiments. First, to establish language categorization of faces, the memory confusion paradigm was used to create two language categories of faces, Spanish and English. Subsequently, participants underwent an oddball paradigm, in which faces that had been previously paired with one of the two languages (Spanish or English), were presented. We measured EEG perceptual differences (vMMN) between standard and two types of deviant faces: within-language category (faces sharing language with standards) or between-language category (faces paired with the other language). Participants were more likely to confuse faces within the language category than between categories, an index that faces were categorized by language. At the neural level, early vMMN were obtained for between-language category faces, but not for within-language category faces. At a later stage, however, larger vMMNs were obtained for those faces from the same language category. Our results showed that language is a relevant social cue that individuals used to categorize others and this categorization subsequently affects face perception.


Assuntos
Reconhecimento Facial , Idioma , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
16.
Sci Rep ; 11(1): 6660, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33758251

RESUMO

Detailed neural encoding of voice pitch and formant structure plays a crucial role in speech perception, and is of key importance for an appropriate acquisition of the phonetic repertoire in infants since birth. However, the extent to what newborns are capable of extracting pitch and formant structure information from the temporal envelope and the temporal fine structure of speech sounds, respectively, remains unclear. Here, we recorded the frequency-following response (FFR) elicited by a novel two-vowel, rising-pitch-ending stimulus to simultaneously characterize voice pitch and formant structure encoding accuracy in a sample of neonates and adults. Data revealed that newborns tracked changes in voice pitch reliably and no differently than adults, but exhibited weaker signatures of formant structure encoding, particularly at higher formant frequency ranges. Thus, our results indicate a well-developed encoding of voice pitch at birth, while formant structure representation is maturing in a frequency-dependent manner. Furthermore, we demonstrate the feasibility to assess voice pitch and formant structure encoding within clinical evaluation times in a hospital setting, and suggest the possibility to use this novel stimulus as a tool for longitudinal developmental studies of the auditory system.


Assuntos
Estimulação Acústica , Encéfalo/fisiologia , Percepção da Altura Sonora , Voz , Adulto , Fatores Etários , Biomarcadores , Cognição , Humanos , Recém-Nascido , Pediatria , Espectrografia do Som , Percepção da Fala
17.
Neuroimage ; 231: 117866, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592244

RESUMO

The frequency-following response (FFR) to periodic complex sounds has gained recent interest in auditory cognitive neuroscience as it captures with great fidelity the tracking accuracy of the periodic sound features in the ascending auditory system. Seminal studies suggested the FFR as a correlate of subcortical sound encoding, yet recent studies aiming to locate its sources challenged this assumption, demonstrating that FFR receives some contribution from the auditory cortex. Based on frequency-specific phase-locking capabilities along the auditory hierarchy, we hypothesized that FFRs to higher frequencies would receive less cortical contribution than those to lower frequencies, hence supporting a major subcortical involvement for these high frequency sounds. Here, we used a magnetoencephalographic (MEG) approach to trace the neural sources of the FFR elicited in healthy adults (N = 19) to low (89 Hz) and high (333 Hz) frequency sounds. FFRs elicited to the high and low frequency sounds were clearly observable on MEG and comparable to those obtained in simultaneous electroencephalographic recordings. Distributed source modeling analyses revealed midbrain, thalamic, and cortical contributions to FFR, arranged in frequency-specific configurations. Our results showed that the main contribution to the high-frequency sound FFR originated in the inferior colliculus and the medial geniculate body of the thalamus, with no significant cortical contribution. In contrast, the low-frequency sound FFR had a major contribution located in the auditory cortices, and also received contributions originating in the midbrain and thalamic structures. These findings support the multiple generator hypothesis of the FFR and are relevant for our understanding of the neural encoding of sounds along the auditory hierarchy, suggesting a hierarchical organization of periodicity encoding.


Assuntos
Estimulação Acústica/métodos , Córtex Auditivo/fisiologia , Vias Auditivas/fisiologia , Percepção Auditiva/fisiologia , Potenciais Evocados Auditivos/fisiologia , Magnetoencefalografia/métodos , Adulto , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Adulto Jovem
18.
Hear Res ; 399: 107954, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32234254

RESUMO

Auditory prediction errors have been extensively associated with the mismatch negativity (MMN), a cortical auditory evoked potential that denotes deviance detection. Yet, many studies lacked the appropriate controls to disentangle sensory adaptation from prediction error. Furthermore, subcortical deviance detection has been shown in humans through recordings of the frequency-following response (FFR), an early auditory evoked potential that reflects the neural tracking of the periodic characteristics of a sound, suggesting the possibility that prediction errors emerge subcortically in the auditory pathway. The present study aimed at investigating the emergence of prediction error along the auditory hierarchy in humans through combined recordings of the FFR and the MMN, tapping at subcortical and cortical levels, respectively, while disentangling prediction error from sensory adaptation with the use of appropriate controls. "Oddball" sequences of pure tones featuring repeated "standard" stimuli (269 Hz; p = 0.8) and rare "deviant" stimuli (p = 0.2; of 289, 329 and 409 Hz delivered in separated blocks to test "frequency separation" effects) were presented to nineteen healthy young participants. "Reversed" oddball sequences (where standard and deviant tones swapped their roles) were presented allowing comparison of responses to same physical stimuli as a function of functional role (i.e., standard, deviant). Critically, control sequences featuring five equiprobable tones (p = 0.2) allowed to dissociate sensory adaptation from prediction error. Results revealed that the MMN amplitude increased as a function of frequency separation yet displayed the same amplitude when retrieved against the control sequences, confirming previous results. FFRs showed repetition enhancement effects across all frequency separations, as supported by larger spectral amplitude to standard than to deviant and control stimuli. This pattern of results provides insights into the hierarchy of the human prediction error system in audition, suggesting that prediction errors in humans emerge at cortical level.


Assuntos
Córtex Auditivo , Estimulação Acústica , Percepção Auditiva , Eletroencefalografia , Potenciais Evocados Auditivos , Humanos , Tempo de Reação
19.
Clin EEG Neurosci ; 52(1): 3-28, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32975150

RESUMO

INTRODUCTION: The global COVID-19 pandemic has affected the economy, daily life, and mental/physical health. The latter includes the use of electroencephalography (EEG) in clinical practice and research. We report a survey of the impact of COVID-19 on the use of clinical EEG in practice and research in several countries, and the recommendations of an international panel of experts for the safe application of EEG during and after this pandemic. METHODS: Fifteen clinicians from 8 different countries and 25 researchers from 13 different countries reported the impact of COVID-19 on their EEG activities, the procedures implemented in response to the COVID-19 pandemic, and precautions planned or already implemented during the reopening of EEG activities. RESULTS: Of the 15 clinical centers responding, 11 reported a total stoppage of all EEG activities, while 4 reduced the number of tests per day. In research settings, all 25 laboratories reported a complete stoppage of activity, with 7 laboratories reopening to some extent since initial closure. In both settings, recommended precautions for restarting or continuing EEG recording included strict hygienic rules, social distance, and assessment for infection symptoms among staff and patients/participants. CONCLUSIONS: The COVID-19 pandemic interfered with the use of EEG recordings in clinical practice and even more in clinical research. We suggest updated best practices to allow safe EEG recordings in both research and clinical settings. The continued use of EEG is important in those with psychiatric diseases, particularly in times of social alarm such as the COVID-19 pandemic.


Assuntos
COVID-19/virologia , Consenso , Eletroencefalografia , SARS-CoV-2/patogenicidade , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , COVID-19/fisiopatologia , Eletroencefalografia/efeitos adversos , Eletroencefalografia/métodos , Humanos , Transtornos Mentais/fisiopatologia
20.
Front Hum Neurosci ; 14: 250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733220

RESUMO

The frequency-following response (FFR) is an auditory evoked potential (AEP) that follows the periodic characteristics of a sound. Despite being a widely studied biosignal in auditory neuroscience, the neural underpinnings of the FFR are still unclear. Traditionally, FFR was associated with subcortical activity, but recent evidence suggested cortical contributions which may be dependent on the stimulus frequency. We combined electroencephalography (EEG) with an inhibitory transcranial magnetic stimulation protocol, the continuous theta burst stimulation (cTBS), to disentangle the cortical contribution to the FFR elicited to stimuli of high and low frequency. We recorded FFR to the syllable /ba/ at two fundamental frequencies (Low: 113 Hz; High: 317 Hz) in healthy participants. FFR, cortical potentials, and auditory brainstem response (ABR) were recorded before and after real and sham cTBS in the right primary auditory cortex. Results showed that cTBS did not produce a significant change in the FFR recorded, in any of the frequencies. No effect was observed in the ABR and cortical potentials, despite the latter known contributions from the auditory cortex. Possible reasons behind the negative results include compensatory mechanisms from the non-targeted areas, intraindividual variability of the cTBS effectiveness, and the particular location of our target area, the primary auditory cortex.

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