Optimized Decoding for Auditory Attention Detection

Thesis (Master's)--University of Washington, 2016-06

Theta EEG oscillatory activity and auditory change detection

The mismatch negativity is an electrophysiological marker of auditory change detection in the event-related brain potential and has been proposed to reflect an automatic comparison process between an incoming stimulus and the representation of prior items in a sequence. There is evidence for two main functional subcomponents comprising the MMN, generated by temporal and frontal brain areas, respectively. Using data obtained in an MMN paradigm, we performed time-frequency analysis to reveal the changes in oscillatory neural activity in the theta band. The results suggest that the frontal component of the MMN is brought about by an increase in theta power for the deviant trials and, possibly, by an additional contribution of theta phase alignment. By contrast, the temporal component of the MMN, best seen in recordings from mastoid electrodes, is generated by phase resetting of theta rhythm with no concomitant power modulation. Thus, frontal and temporal MMN components do not only differ with regard to their functional significance but also appear to be generated by distinct neurophysiological mechanisms.

A proposed behavioral tool to assess sustained auditory attention

Sustained attention and vigilance are processeses that characterize attention, and are essential for the development of certain abilities Aim: a prospective study to propose a simple, easy and quick behavioral tool to support the assessment of sustained auditory attention. Material and methods: volunteer children aged between 6 and 11 years (139 female and 141 male) were selected. The test was named Sustained Auditory Attention Ability Test, and is based on the Continuous Performance Test. It consist of a binaural and diotic presentation of a list of 100 monosyllabic words in which a target monosyllable is included 20 times. This list was presented six times with no breaks. The test was carried out in a soundproofed room, using a CD player attached to a two-channel audiometer at 50 dBSL during 9 minutes. The test resulted in a total score and a vigilance decrement. Results: There was no statistically significant difference between genders, but a significant difference was found between ages. Conclusion: The proposed test had no discomfort for the participants, and was shown to be extremely promising to assess the sustained auditory attention ability in children. © Revista Brasileira de Otorrinolaringologia. All Rights reserved.

Influence of silence and attention on tinnitus perception

OBJECTIVE: The purpose of this study was to study the effect of attention and sustained silence on the emergence of auditory phantom perception in normal-hearing adults. STUDY DESIGN: Cross-sectional survey. SUBJECTS AND METHODS: While sitting in a sound booth, 66 volunteers (age range. 18-65; mean age, 37.3) performed 3 experiments of 5 minutes each, consecutively and randomly presented. Two deviated attention from auditory system (Hanoi and visual attention experiments). and 1 drove attention to the auditory system (auditory attention). After each experiment, participants were asked about their auditory and visual perception. No sound or light change was given at any moment. RESULTS: Of the participants, 19.7% experienced tinnitus during Hanoi, 45.5% during visual attention, and 68.2% during auditory attention experiment. with no significant differences for studied variables. CONCLUSION: Tinnitus-like perceptions may occur in a non-clinical population in a silent environment. Concomitant auditory attention plays an important role on the emergence of tinnitus. (C) 2008 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Selection of information in auditory virtual reality

ERP, auditory virtual reality, dichotic listening, selective auditory attention, cocktail-party phenomenon, HRTF

Central auditory processing and the acquisition of phonology in 2-year-old children with recurrent acute otitis media

Middle ear infections (acute otitis media, AOM) are among the most common infectious diseases in childhood, their incidence being greatest at the age of 6–12 months. Approximately 10–30% of children undergo repetitive periods of AOM, referred to as recurrent acute otitis media (RAOM). Middle ear fluid during an AOM episode causes, on average, 20–30 dB of hearing loss lasting from a few days to as much as a couple of months. It is well known that even a mild permanent hearing loss has an effect on language development but so far there is no consensus regarding the consequences of RAOM on childhood language acquisition. The results of studies on middle ear infections and language development have been partly discrepant and the exact effects of RAOM on the developing central auditory nervous system are as yet unknown. This thesis aims to examine central auditory processing and speech production among 2-year-old children with RAOM. Event-related potentials (ERPs) extracted from electroencephalography can be used to objectively investigate the functioning of the central auditory nervous system. For the first time this thesis has utilized auditory ERPs to study sound encoding and preattentive auditory discrimination of speech stimuli, and neural mechanisms of involuntary auditory attention in children with RAOM. Furthermore, the level of phonological development was studied by investigating the number and the quality of consonants produced by these children. Acquisition of consonant phonemes, which are harder to hear than vowels, is a good indicator of the ability to form accurate memory representations of ambient language and has not been studied previously in Finnish-speaking children with RAOM. The results showed that the cortical sound encoding was intact but the preattentive auditory discrimination of multiple speech sound features was atypical in those children with RAOM. Furthermore, their neural mechanisms of auditory attention differed from those of their peers, thus indicating that children with RAOM are atypically sensitive to novel but meaningless sounds. The children with RAOM also produced fewer consonants than their controls. Noticeably, they had a delay in the acquisition of word-medial consonants and the Finnish phoneme /s/, which is acoustically challenging to perceive compared to the other Finnish phonemes. The findings indicate the immaturity of central auditory processing in the children with RAOM, and this might also emerge in speech production. This thesis also showed that the effects of RAOM on central auditory processing are long-lasting because the children had healthy ears at the time of the study. An effective neural network for speech sound processing is a basic requisite of language acquisition, and RAOM in early childhood should be considered as a risk factor for language development.

Whole-body motion discrimination in the visually impaired

Visually impaired people show superior abilities in various perception tasks such as auditory attention, auditory temporal resolution, auditory spatial tuning, and odor discrimination. However, with the use of psychophysical methods, auditory and olfactory detection thresholds typically do not differ between visually impaired and sighted participants. Using a motion platform we investigated thresholds of passive whole-body motion discrimination in nine visually impaired participants and nine age-matched sighted controls. Participants were rotated in yaw, tilted in roll, and translated along the y-axis at two different frequencies (0.3 Hz and 2 Hz). An adaptive 3-down 1-up staircase procedure was used along with a two-alternative direction (leftward vs. rightward) discrimination task. Superior performance of visually impaired participants was found in the 0.3 Hz roll tilt condition. No differences between the visually impaired and controls were observed in all other types of motion. The superior performance in the 0.3 Hz roll tilt condition could reflect differences in the integration of extra-vestibular cues and increased sensitivity towards changes in the direction of the gravito-inertial force. In the absence of visual information, roll tilts entail a more pronounced risk of falling, and this could eventually account for the group difference. It is argued that differences in experimental procedures (i.e. detection vs. discrimination of stimuli) explain the discrepant findings across perceptual tasks comparing blind and sighted participants.

Diferencias en funciones ejecutivas en escolares normales, con trastorno por déficit de atención e hiperactividad, trastorno del cálculo y condición comórbida

El objetivo del presente estudio descriptivo-comparativo fue comparar el desempeño en funciones ejecutivas de escolares entre ocho y trece años con trastorno por déficit de atención e hiperactividad (TDAH), trastorno del cálculo (TC), TDAH+TC y controles normales. Los diagnósticos se confirmaron a través de una entrevista clínica semiestructurada, un cuestionario clínico de déficit atencional y pruebas de cálculo matemático. Se encontraron diferencias estadísticamente significativas entre los grupos en atención visual y auditiva, fluidez verbal fonémica, flexibilidad cognitiva, organización y planeación. Los resultados indican, de manera similar que investigaciones anteriores, que los escolares con TDAH+TC presentan mayores déficits en funciones ejecutivas que los niños normales.

Noise, predation risk compensation and vigilance in the chaffinch Fringilla coelebs

Background noise should in theory hinder detection of auditory cues associated with approaching danger. We tested whether foraging chaffinches Fringilla coelebs responded to background noise by increasing vigilance, and examined whether this was explained by predation risk compensation or by a novel stimulus hypothesis. The former predicts that only inter-scan interval should be modified in the presence of background noise, not vigilance levels generally. This is because noise hampers auditory cue detection and increases perceived predation risk primarily when in the head-down position, and also because previous tests have shown that only interscan interval is correlated with predator detection ability in this system. Chaffinches only modified interscan interval supporting this hypothesis. At the same time they made significantly fewer pecks when feeding during the background noise treatment and so the increased vigilance led to a reduction in intake rate, suggesting that compensating for the increased predation risk could indirectly lead to a fitness cost. Finally, the novel stimulus hypothesis predicts that chaffinches should habituate to the noise, which did not occur within a trial or over 5 subsequent trials. We conclude that auditory cues may be an important component of the trade-off between vigilance and feeding, and discuss possible implications for anti-predation theory and ecological processes

Escuta de crianças com fissura labiopalatina na escola

INTRODUÇÃO: Grande similaridade entre o comportamento de pacientes com fissura labiopalatina e aqueles com transtorno de processamento auditivo são relatadas por pais e professores. OBJETIVO: Verificar a escuta de crianças com fissura labiopalatina em seis condições de escuta. MÉTODO: Professores de 224 escolares (7 a 11 anos) com fissura completaram um questionário, visando julgar a escuta do escolar no ruído, condição ideal, com múltiplos estímulos, no silêncio, quando solicitado recordar a informação ouvida e durante longo período de escuta, comparando-o ao de outro sem fissura de mesma idade e condição de escuta. Estudo Prospectivo. RESULTADOS: A média do julgamento (-0,08, desvio padrão de 0,27) dos alunos com fissura, realizado pelo professor, foi aproximadamente ao de mesma dificuldade (zero), quando comparado com o escolar sem fissura. Não foi encontrada significância estatística para qualquer uma das condições, nem para o valor total do questionário considerando os gêneros e as séries escolares. CONCLUSÃO: As características de escuta dos escolares com fissura labiopalatina foram similares ao de outro sem esta malformação craniofacial de mesma idade e condição de escuta semelhante. No ruído, quando a memória e a atenção auditiva são requeridas foram as condições mais difíceis.

Aplicabilidade do teste da habilidade de atenção auditiva sustentada - THAAS em campo livre

INTRODUÇÃO: A atenção é uma função neuropsicológica subjacente a todos os processos cognitivos. A deficiência auditiva compromete o desenvolvimento normal da criança, alterando diversas habilidades auditivas, incluindo a atenção. OBJETIVO: comparar o desempenho de crianças no Teste da Habilidade de Atenção Auditiva Sustentada-THAAS, no que se refere às diferentes formas de aplicação (fones auriculares e campo livre), gênero e, ordem de aplicação. MÉTODO: participaram 40 crianças (7 anos) voluntárias com desenvolvimento típico, divididas em dois grupos: G1 e G2, compostos de 20 crianças cada. A aplicação do THAAS no G1 se deu primeiramente com fones auriculares e em seguida em campo livre e no G2 o processo foi inverso. A avaliação constituiu-se em: questionário específico, testes auditivos e aplicação do THAAS. RESULTADOS: Não houve diferença significante quanto ao gênero. Para o THAAS com fones, o G1 apresentou maior quantidade de erros de desatenção e pontuação total. Para o THAAS em campo houve uma diferença significante do G2 para o decréscimo de vigilância. Quanto à forma de aplicação, o G1 demonstrou um número maior de erros quando foi utilizado fones. O G2 não demonstrou diferença. CONCLUSÃO: Houve viabilidade na aplicação do THAAS em Campo Livre, podendo ser adotado os mesmos valores normativos usados para o modo convencional de avaliação.

Percepção dos pais sobre a habilidade de atenção auditiva de seu filho com fissura labiopalatina: estudo retrospectivo

INTRODUÇÃO: Para processar e decodificar o estímulo acústico são necessários mecanismos cognitivos e neurofisiológicos. O estímulo auditivo sofre influências de fatores cognitivos de nível mais alto, tais como a memória, atenção e aprendizagem. A privação sensorial ocasionada por perda auditiva do tipo condutiva, frequente na população com fissura labiopalatina, pode afetar várias funções cognitivas - dentre elas a atenção, além de prejudicar os desempenhos escolares, linguísticos e interpessoais. OBJETIVO: Verificar a percepção dos pais de crianças com fissura labiopalatina sobre a atenção auditiva de seus filhos. MÉTODO: Estudo retrospectivo de crianças com qualquer tipo de fissura labiopalatina, sem qualquer síndrome genética associada cujos pais responderam a um questionário pertinente sobre a habilidade de atenção auditiva. RESULTADOS: 44 são do gênero masculino e 26 do gênero feminino, 35,71% das respostas foram afirmativas para a presença de perda auditiva e 71,43% para infecções otológicas. CONCLUSÃO: A maioria dos pais entrevistados apontou pelo menos um dos comportamentos relacionados à atenção contidos no questionário, indicando que a presença de fissura labiopalatina pode estar relacionada com dificuldades quanto à atenção auditiva.

Competition for neuronal resources: how hallucinations make themselves heard

BACKGROUND: Hallucinations are perceptions in the absence of a corresponding external sensory stimulus. However, during auditory verbal hallucinations, activation of the primary auditory cortex has been described. AIMS: The objective of this study was to investigate whether this activation of the auditory cortex contributes essentially to the character of hallucinations and attributes them to alien sources, or whether the auditory activation is a sign of increased general auditory attention to external sounds. METHOD: The responsiveness of the auditory cortex was investigated by auditory evoked potentials (N100) during the simultaneous occurrence of hallucinations and external stimuli. Evoked potentials were computed separately for periods with and without hallucinations; N100 power, topography and brain electrical sources were analysed. RESULTS: Hallucinations lowered the N100 amplitudes and changed the topography, presumably due to a reduced left temporal responsivity. CONCLUSIONS: This finding indicates competition between auditory stimuli and hallucinations for physiological resources in the primary auditory cortex. The abnormal activation of the primary auditory cortex may thus be a constituent of auditory hallucinations.

Évaluation électrophysiologique auditive et examen du langage et de l’attention chez l’enfant né prématurément et l’enfant né à terme

L’objectif de cette thèse est l’étude du développement de l’attention auditive et des capacités de discrimination langagière chez l’enfant né prématurément ou à terme. Les derniers mois de grossesse sont particulièrement importants pour le développement cérébral de l’enfant et les conséquences d’une naissance prématurée sur le développement peuvent être considérables. Les enfants nés prématurément sont plus à risque de développer une variété de troubles neurodéveloppementaux que les enfants nés à terme. Même en l’absence de dommages cérébraux visibles, de nombreux enfants nés avant terme sont à risque de présenter des troubles tels que des retards langagiers ou des difficultés attentionnelles. Dans cette thèse, nous proposons donc une méthode d’investigation des processus préattentionnels auditifs et de discrimination langagière, à l’aide de l’électrophysiologie à haute densité et des potentiels évoqués auditifs (PEAs). Deux études ont été réalisées. La première visait à mettre sur pied un protocole d’évaluation de l’attention auditive et de la discrimination langagière chez l’enfant en santé, couvrant différents stades de développement (3 à 7 ans, 8 à 13 ans, adultes ; N = 40). Pour ce faire, nous avons analysé la composante de Mismatch Negativity (MMN) évoquée par la présentation de sons verbaux (syllabes /Ba/ et /Da/) et non verbaux (tons synthétisés, Ba : 1578 Hz/2800 Hz ; Da : 1788 Hz/2932 Hz). Les résultats ont révélé des patrons d’activation distincts en fonction de l’âge et du type de stimulus présenté. Chez tous les groupes d’âge, la présentation des stimuli non verbaux a évoqué une MMN de plus grande amplitude et de latence plus rapide que la présentation des stimuli verbaux. De plus, en réponse aux stimuli verbaux, les deux groupes d’enfants (3 à 7 ans, 8 à 13 ans) ont démontré une MMN de latence plus tardive que celle mesurée dans le groupe d’adultes. En revanche, en réponse aux stimuli non verbaux, seulement le groupe d’enfants de 3 à 7 ans a démontré une MMN de latence plus tardive que le groupe d’adulte. Les processus de discrimination verbaux semblent donc se développer plus tardivement dans l’enfance que les processus de discrimination non verbaux. Dans la deuxième étude, nous visions à d’identifier les marqueurs prédictifs de déficits attentionnels et langagiers pouvant découler d’une naissance prématurée à l’aide des PEAs et de la MMN. Nous avons utilisé le même protocole auprès de 74 enfants âgés de 3, 12 et 36 mois, nés prématurément (avant 34 semaines de gestation) ou nés à terme (au moins 37 semaines de gestation). Les résultats ont révélé que les enfants nés prématurément de tous les âges démontraient un délai significatif dans la latence de la réponse MMN et de la P150 par rapport aux enfants nés à terme lors de la présentation des sons verbaux. De plus, les latences plus tardives de la MMN et de la P150 étaient également corrélées à des performances langagières plus faibles lors d’une évaluation neurodéveloppementale. Toutefois, aucune différence n’a été observée entre les enfants nés à terme ou prématurément lors de la discrimination des stimuli non verbaux, suggérant des capacités préattentionnelles auditives préservées chez les enfants prématurés. Dans l’ensemble, les résultats de cette thèse indiquent que les processus préattentionnels auditifs se développent plus tôt dans l'enfance que ceux associés à la discrimination langagière. Les réseaux neuronaux impliqués dans la discrimination verbale sont encore immatures à la fin de l'enfance. De plus, ceux-ci semblent être particulièrement vulnérables aux impacts physiologiques liés à la prématurité. L’utilisation des PEAs et de la MMN en réponse aux stimuli verbaux en bas âge peut fournir des marqueurs prédictifs des difficultés langagières fréquemment observées chez l’enfant prématuré.