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Active Perception perspectives claim that action is closely related to perception. An empirical approach that supports these theories is the minimalist, in which participants perform a task using an interface that provides minimal information. Their exploratory movements are crucial to generating a meaningful sequence of information. Previous studies analyzed sensorimotor trajectories describing qualitative strategies and linear quantification of participants' movement performance, but that approach struggles to capture the behavior of non-stationary data. In the present study, we applied the recurrence plot (RP) and recurrence quantification analysis (RQA) to study the structure of sensorimotor trajectories developed by participants trying to discriminate between two invisible geometric shapes (Triangle or Rectangle). The exploratory movements were made using a computer mouse and sonification-mediated feedback was provided, which depended exclusively on whether the pointer was inside or outside the shape. We applied RP and RQA to the sensorimotor trajectories, with the aim of studying their fine structure characteristics, focusing on their repetitive patterns. Recurrence analysis proved to be useful for quantifying differences in dynamic behavior that emerge when participants explore invisible virtual geometric shapes. The differences obtained in RQA-based measures associated with the vertical structures allowed to postulate the existence of particular exploration strategies for each figure. It was also possible to determine that the complexity of the dynamics changed according to the shape. We discuss these results in light of antecedents in haptic and visual perceptual exploration.

Introduction: The most common cause of tinnitus is the exposure to noise; in the case of adolescents, music is the main sound source they are exposed to. Currently, one of the hypotheses about the genesis of tinnitus is related to the deterioration in the functioning of the medial olivocochlear system (MOCS). Aim: The aim of this study was to determine the presence or absence of tinnitus in adolescents with normal hearing and to relate it to: (a) the functioning of the MOCS, by the contralateral suppression of the transient evoked otoacoustic emissions (TEOAEs) and (b) the musical general exposure (MGE). Materials and Methods: A cross-sectional descriptive correlational study was conducted. The sample was composed by adolescents with ages between 14 and 15. Two questionnaires were administered, one in relation to the subjective report of tinnitus and the other in relation to recreational activities to know the MGE. Results: The results showed that the amplitude of frequencies (1000, 1500, 2000, and 3000 Hz) and global amplitude of TEOAEs, with and without acoustic contralateral stimulation, were higher in the group without tinnitus, with a statistically significant difference (P < 0.05). The suppressive effect was higher in the group without tinnitus; however, there was no statistically significant difference. Contrastingly, a significant association (P < 0.05) between exposure to music and tinnitus was observed; 72.41% of the adolescents with high exposure to music had tinnitus. Discussion and Conclusion: The results of the present investigation provide a contribution to the hypothesis of “the participation of the MOCS.” Furthermore, a high MGE can be considered a risk factor for the onset of tinnitus.

There is a growing interest in the development and the evaluation of real-time auditory virtual environments (AVE). The implementation of this type of simulation system in general purpose computers is a still a challenge, and there are few studies that evaluated the perceived quality of synthetized sounds of simulated acoustic scenes. To evoke in the listener a correct image of the modeling space, the system must be dynamic and interactive. That is, it must respond to the changes in the acoustic scenario produced by the listener movement, in a perceptually acceptable time and with an update rate that guarantees continuity in the reproduction of sound events. Hard real-time systems ensure that a given task runs within a given time interval, providing deterministic behavior for applications with time restrictions. In the current article, a computational model to implement binaural synthesis in a hard real-time AVE is presented and evaluated. The computer model was implemented in an open-source auralization system. Measurements and real-time simulations on a university classroom were carried out to perform a reverberation time parameters validation and a system performance evaluation. Also, measured and simulated binaural soundtracks (composed from anechoic stimuli) were compared in terms of three selected perceptual attributes for subjective evaluations of static positions. The results showed that real-time performance was acceptable according to values previously reported in the literature and that computer prediction errors for the measured parameters were within the subjective difference limens. The computational model was able to generate an AVE with an acceptable overall perceptual quality. Fil: Tommasini, Fabián Carlos. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomia y Física. Sección Matemática. Grupo de Probabilidad y Estadística; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Transferencia en Acústica; Argentina Fil: Ramos, Oscar Alberto. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Transferencia en Acústica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Hüg, Mercedes. Centro de Investigación y Transferencia en Acústica; Argentina Fil: Ferreyra, Sebastian Pablo. Centro de Investigación y Transferencia en Acústica; Argentina

La exposición a ruido no ocupacional y a la música a alto nivel sonoro, constituye un creciente factor de riesgo de pérdida auditiva en adolescentes. Estudios internacionales postulan que una función importante del Sistema Eferente Medial (SEM) es proteger el oído interno frente al ruido mediante un mecanismo reflejo y que puede ser evaluado a través de la Supresión Contralateral (SC) de las otoemisiones acústicas transitorias (TEOAEs). El mecanismo subyacente de este fenómeno no se conoce en su totalidad y los antecedentes sobre el tema son escasos. En esta investigación se analizó la relación entre la Exposición General a Música (EGM), el estado de la función auditiva y el mecanismo de protección coclear. Participaron 91 adolescentes con edades entre 14 y 15 años. Se evaluaron dos dimensiones (a) Psicosocial: se examinó la EGM con un cuestionario de actividades extraescolares y (b) auditiva o sea el funcionamiento del SEM mediante SC de las TEOAEs y los perfiles audiométricos con audiometrías. Los resultados mostraron que la SC no influyó estadísticamente en los perfiles audiométricos y categorías de exposición. Sin embargo, los resultados de la SC se orientan hacia la menor magnitud de efecto supresor, disminución en la respuesta total en relación al descenso de los umbrales auditivos y en relación con las categorías alta y baja de EGM. Es necesario promover trabajos destinados al comportamiento de riesgo auditivo conjuntamente con el mecanismo protector del SEM. De esta manera se podrá contribuir en la identificación temprana de la sensibilidad auditiva en adolescentes expuestos a ruido no ocupacional. Non-occupational exposure to noise, such as loud music sound level is an increasing risk factor for hearing loss in adolescents. International studies propose that an important function of the medial efferent system (MES) is protect the inner ear against noise by a reflex mechanism and can be evaluated through Contralateral Suppression (CS) of transient otoacoustic emissions (TEOAEs) to analyzing the presence or absence of suppressive effect. The absence of suppressive effect is considered a possible alteration of the MES and the role it exerts on the regulation of the outer hair cells. The underlying mechanism of this phenomenon is not known totality and the background about this topic are limited. However, researches suggests that MES would have an important role in protection against acoustic overstimulation under the hypothesis that a hearing with the presence of suppressive effect would tend to be more protected against exposure to high noise levels while ears with no effect suppressor may be more vulnerable to noise exposure. In this research the relationship between the General Exposure to Music (MGE), the state of hearing function and cochlear protection mechanism were analyzed in 91 adolescents with 14/15 years old, with male predominance, of two technical schools of the city of Córdoba (Argentina). Were evaluated the following dimensions: (a) Psychosocial: MGE through an Out of School Activities Questionnaire to know in detail the participation in five recreational activities to finally analyze the MGE and (b) Audiological: assessment of audiometric profiles, as a subjective method, by audiometry in the conventional frequency ranges (250-8000) Hz and an extended high frequency audiometry (8000-16000) Hz; function of MES assessment, objective method, through CS of TEOAEs to determine the presence or absence of suppressive effect. The study CS of TEOAEs consisted of two steps: Step 1, application of TEOAEs of an ear in form ipsilateral without acoustic stimulation in the contralateral ear (CAS) and Step 2, application of TEOAEs in the ear ipsilateral while applying CAS. Was considered presence of suppressive effect when there was a reduction in the response after the CAS that is to say when the difference of values obtained in the total response with and without CAS was positive. At the same time, was considered absence of suppressive effect in cases of maintained or increased the response after the CAS, obtaining a value of zero or negative. The results of the research showed that in the group with presence of suppressive effect the most of ears is among moderate and high categories of MGE with a lower average magnitude of suppressive effect and a decreased amplitude of the total response in the high category of MGE than the media category. Regarding audiometry the ears with presence of suppressive effect showed higher magnitude in the group of normal hearing thresholds compared with the group of descended hearing thresholds. The results related to CS of the TEOAEs statistically did not influence in the audiometric profiles and the exposure categories. However the results of the CS were oriented towards the smaller magnitude of suppressive effect, decreased total response related with the descended hearing thresholds and high and low categories of MGE. It is necessary to promote and intensify researches in relation to the auditory risk behaviors together with the protection mechanism of MES. In this way, more researches can contribute to the early identification of hearing sensitivity in adolescents exposed to non-occupational noise. It is important to implement a Psycho-Auditory Screening to collaborate in the prevention and promotion of hearing health.

The precedence effect is a spatial hearing phenomenon implicated in sound localization on reverberant environments. It occurs when a pair of sounds, with a brief delay between them, is presented from different directions; listeners give greater perceptual weight to localization cues coming from the first-arriving sound, called lead, and suppress localization cues from the later-arriving reflection, called lag. Developmental studies with sighted infants show that the first responses to precedence effect stimuli are observed at 4-5 months of life. In this exploratory study, we use the minimum audible angle (MAA) paradigm in conjunction with the observer-based psychophysical procedure to test the ability of infants and toddlers, with visual impairment and normal vision, to discriminate changes in the azimuthal position of sounds configured under precedence effect conditions. The results indicated that similar and, in some conditions, higher performances were obtained by blind toddlers when compared to sighted children of similar age, and revealed that the observer-based psychophysical procedure is a valuable method to measure auditory localization acuity in infants and toddlers with visual impairment. The video records showed auditory orienting behaviors specific of the blind children group. Fil: Hug, Mercedes Ximena. Universidad Tecnológica Nacional. Facultad Regional Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Centro de Investigación y Transferencia en Acústica; Argentina. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina Fil: Arias, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba; Argentina. Centro de Investigación y Transferencia en Acústica; Argentina Fil: Tommasini, Fabián Carlos. Centro de Investigación y Transferencia en Acústica; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina Fil: Ramos, Oscar Alberto. Universidad Tecnológica Nacional. Facultad Regional Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Centro de Investigación y Transferencia en Acústica; Argentina

Acoustics is an inherently interdisciplinary science involved in the study and remediation of very hot social topics. For its part, the university has a crucial role in knowledge generation with social responsibility heading to an equalitarian society. Argentinean scientific policy, promotes: a) interdisciplinary and inter institutional scientific teams, b) an unified national system of science and technology and c) the linkage of this system with educational and productive sectors. At the same time, new paradigms of higher education give a central place to the student learning process of research abilities. In such complex scenario a research center has a key role in achieving these goals. Nowadays CINTRA (Centro de Investigacion y Transferencia en Acustica) is involved in a collective construction pointing towards innovative dynamics encouraging the emergence of synergetic networks in which theory-practice and research-technology are naturally joined. This paper describes three CINTRA’s ongoing programs...

The sensorimotor approach proposes that perception is constituted by the mastery of lawful sensorimotor regularities or sensorimotor contingencies (SMCs), which depend on specific bodily characteristics and on actions possibilities that the environment enables and constrains. Sensory substitution devices (SSDs) provide the user information about the world typically corresponding to one sensory modality through the stimulation of another modality. We investigate how perception emerges in novice adult participants equipped with vision-to-auditory SSDs while solving a simple geometrical shape recognition task. In particular, we examine the distinction between apparatus-related SMCs (those originating mostly in properties of the perceptual system) and object-related SMCs (those mostly connected with the perceptual task). We study the sensorimotor strategies employed by participants in three experiments with three different SSDs: a minimalist head-mounted SSD, a traditional, also head-mounted SSD (the vOICe) and an enhanced, hand-held echolocation device. Motor activity and fist- person data are registered and analyzed. Results show that participants are able to quickly learn the necessary skills to distinguish geometric shapes. Comparing the sensorimotor strategies utilized with each SSD we identify differential features of the sensorimotor patterns attributable mostly to the device, which account for the emergence of apparatus-based SMCs. These relate to differences in sweeping strategies between SSDs. We identify, also, components related to the emergence of object-related SMCs. These relate mostly to exploratory movements around the border of a shape. The study provides empirical support for SMC theory and discusses considerations about the nature of perception in sensory substitution. Fil: Bermejo, Fernando Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Transferencia en Acústica; Argentina. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina Fil: Di Paolo, Ezequiel Alejandro. Basque Foundation for Science; España. Universidad del País Vasco; España. University of Sussex; Reino Unido Fil: Hüg, Mercedes X.. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Transferencia en Acústica; Argentina Fil: Arias, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Transferencia en Acústica; Argentina

Measuring the head-related transfer functions (HRTFs) for each subject is a complex process. Therefore, it is necessary to develop procedures that allow the estimation of personalized HRTFs. It is common to estimate the weights of the principal component analysis (PCA) of a group of subjects based on some anthropometric parameters using multivariable regression modelling. Moreover, to objectively evaluate the goodness of fit between the original HRTFs and the personalized ones, the spectral distortion (SD) is usually used too. However, its suitability in the median plane, in which the spectral profiles are crucial to localize a sound source, has not yet been demonstrated. This paper analyses the validity of the SD as a measure of the quality of the HRTF personalization in the median plane, from the localization point of view. The HRTFs were modelled from the weights estimated by multiple linear regression and artificial neural networks (ANNs). The SD was used to compare the HRTFs measured with those estimated. Likewise, the level of fitting accuracy of characteristic resonance and notches in the median plane was also compared. Despite the fact that the SD scores of ANNs are lower than those of the multiple linear regression and are similar to those reported by other studies, the errors obtained from analysing both central frequencies and levels for resonance and notches could be discriminated.

El estudio científico de la habilidad para localizar sonidos en niños con visión normal se inició a comienzos de los 80. Sin embargo, en el caso de los niños ciegos, las investigaciones realizadas sobre este tema son exiguas. En el presente trabajo se presenta una revisión de artículos sobre el desarrollo motor y cognitivo de los niños ciegos que evaluaron conductas de localización sonora en la primera infancia. En primer lugar, se sintetizan trabajos pioneros realizados en la década del 60 y luego se presentan investigaciones realizadas a partir de la década del 80. Por último, se analizan e integran los principales resultados de estos trabajos, se discuten sus implicancias y se plantean algunos de los interrogantes aún no resueltos en este campo del conocimiento The scientific study of the ability to localize sounds in children with normal vision began in the early 80s. However, in the case of blind children, scarce research has been conducted on this subject. This paper presents a review of articles on cognitive and motor development of blind children that evaluated sound localization behaviors in early childhood. First, pioneering studies published in the 60s are summarized and then researches from the 80s are presented. Finally, the main findings of these papers are analyzed and integrated, their implications are discussed and some questions unresolved in this field of knowledge are stated. Fil: Hug, Mercedes Ximena. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina. Universidad Tecnologica Nacional. Facultad Regional Cordoba. Centro de Investigacion y Transferencia En Acustica. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Centro de Investigacion y Transferencia En Acustica.; Argentina Fil: Arias, Claudia. Universidad Tecnologica Nacional. Facultad Regional Cordoba. Centro de Investigacion y Transferencia En Acustica. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Centro de Investigacion y Transferencia En Acustica.; Argentina. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina