Pentatonic sequences and monaural beats to facilitate relaxation: an EEG study.

Introduction: In two studies we investigated if specific acoustic stimulations could be more effective to induce a relaxation response in comparison to silence. Acoustic stimulations included monaural beats and musical sequences based on a pentatonic scale.

Methods: In the first study, 47 participants evaluated monaural beats and pentatonic sequences presented through loudspeakers and varying along three frequencies (0.

Metacognition for hearing in noise: a comparison between younger and older adults.

Metacognition entails knowledge of one's own cognitive skills, perceived self-efficacy and locus of control when performing a task, and performance monitoring. Age-related changes in metacognition have been observed in metamemory, whereas their occurrence for hearing remained unknown. We tested 30 older and 30 younger adults with typical hearing, to assess if age reduces metacognition for hearing sentences in noise.

Indoor soundscape in primary school classroomsa).

Soundscape research on indoor environments is emerging as a topic to be addressed for the design of supportive, healthier, and more comfortable spaces. Only a few studies so far addressed the context of educational buildings, mainly focusing on high schools and universities. This pilot study uses questionnaires based on pictorial scales to investigate the indoor soundscape of classrooms for primary school children (n = 130; 8-10 years old).

Individual characteristics moderate listening effort in noisy classrooms.

Comprehending the teacher's message when other students are chatting is challenging. Even though the sound environment is the same for a whole class, differences in individual performance can be observed, which might depend on a variety of personal factors and their specific interaction with the listening condition. This study was designed to explore the role of individual characteristics (reading comprehension, inhibitory control, noise sensitivity) when primary school children perform a listening comprehension task in the presence of a two-talker masker.

Be Quiet! Effects of Competing Speakers and Individual Characteristics on Listening Comprehension for Primary School Students.

Students learn in noisy classrooms, where the main sources of noise are their own voices. In this sound environment, students are not equally at risk from background noise interference during lessons, due to the moderation effect of the individual characteristics on the listening conditions. This study investigates the effect of the number of competing speakers on listening comprehension and whether this is modulated by selective attention skills, working memory, and noise sensitivity.

Effects of type of early reflection, clarity of speech, reverberation and diffuse noise on the spatial perception of a speech source and its intelligibility.

Changing the balance between the early and late reflections in the impulse response affects the clarity of speech, and also the spatial perception of the sound source is affected when the direction of the early reflections is manipulated. While the effect of noise on early reflections has long been investigated in speech intelligibility studies, it is unclear whether and how the spatial characteristics of the source are altered by noise, and whether this would influence speech intelligibility in any way. The aim of the present work was to analyze the spatial perception of a speech source in noise and its relationship, if any, with speech intelligibility.

Effects of multiple early diffuse reflections on spatial percepts.

While the use of diffuse surfaces is becoming increasingly common in the acoustical design of performance venues and normal rooms, there is a paucity of data on the auditory perceptual effects that characterize those finishes compared to specular ones. For instance, it is not entirely clear whether and how the aural impression is affected when first reflections are swapped from specular to diffuse. In a recent work, after revising the background knowledge on physical and perceptual effects of scattering, Visentin et al.

A comparison of simultaneously-obtained measures of listening effort: pupil dilation, verbal response time and self-rating.

Objective: The aim of this study was to assess to what extent measures of listening effort (task-evoked pupil dilation, verbal response time [RT], and self-rating) could be sensitive to auditory and cognitive manipulations in a speech perception task. The study also aimed to explore the possible relationship between RT and pupil dilation.

Design: A within-group design was adopted.

A Slight Increase in Reverberation Time in the Classroom Affects Performance and Behavioral Listening Effort.

Objectives: The purpose of this study was to investigate the effect of a small change in reverberation time (from 0.57 to 0.69 s) in a classroom on children's performance and listening effort.

Effect of a single lateral diffuse reflection on spatial percepts and speech intelligibility.

This study examines the influence of an early lateral reflection on spatial perceptual attributes and speech reception. To this aim, a diffuse reflection is compared with a specular one. Although diffusive surfaces have widespread applications in room acoustics design, the knowledge of the perceptual and behavioral outcomes of these surfaces has yet to be fully developed.

Impact of Background Noise Fluctuation and Reverberation on Response Time in a Speech Reception Task.

Purpose This study examines the effects of reverberation and noise fluctuation on the response time (RT) to the auditory stimuli in a speech reception task. Method The speech reception task was presented to 76 young adults with normal hearing in 3 simulated listening conditions (1 anechoic, 2 reverberant). Speechlike stationary and fluctuating noise were used as maskers, in a wide range of signal-to-noise ratios.

Noise, Age, and Gender Effects on Speech Intelligibility and Sentence Comprehension for 11- to 13-Year-Old Children in Real Classrooms.

The present study aimed to investigate the effects of type of noise, age, and gender on children's speech intelligibility (SI) and sentence comprehension (SC). The experiment was conducted with 171 children between 11 and 13 years old in ecologically-valid conditions (collective presentation in real, reverberating classrooms). Two standardized tests were used to assess SI and SC.

Investigating Listening Effort in Classrooms for 5- to 7-Year-Old Children.

Purpose This study aims to investigate the listening effort made by young children in real classrooms during a prolonged speech reception task in the presence of background noise. Method The experiment was proposed to 117 typically developing kindergarten and primary school pupils, aged 5-7 years old. An ecological experimental approach was followed, and speech-in-noise tests were presented in the classrooms to groups made up of the whole class.

A Matrixed Speech-in-Noise Test to Discriminate Favorable Listening Conditions by Means of Intelligibility and Response Time Results.

Purpose: The primary aim of this study was to develop and examine the potentials of a new speech-in-noise test in discriminating the favorable listening conditions targeted in the acoustical design of communication spaces. The test is based on the recognition and recall of disyllabic word sequences. A secondary aim was to compare the test with current speech-in-noise tests, assessing its benefits and limitations.

Listening efficiency during lessons under various types of noise.

Pupils inside primary school classrooms can be exposed to extraneous noise, impairing their performance in the speech reception process. The different noises show a peculiar impact, depending on their level, spectral content and temporal fine structure. In order to understand how the disturbance is built up over time, in this work a large data set was analyzed, detailing the changes of pupils' performance as the lesson progresses from the start to the end.

An Italian matrix sentence test for the evaluation of speech intelligibility in noise.

Objective: Development of an Italian matrix sentence test for the assessment of speech intelligibility in noise.

Design: The development of the test included the selection, recording, optimization with level adjustment, and evaluation of speech material. The training effect was assessed adaptively during the evaluation measurements with six lists of 20 sentences, using open- and closed-set response formats.

Experimental analysis of the relationship between reverberant acoustic intensity and energy density inside long rooms.

In this paper, the validity of the Fick's law of diffusion in room acoustics is experimentally investigated inside long rooms. The room-acoustics diffusion model relies on Fick's law stating a proportionality relationship between sound intensity and energy density gradient inside a room through a constant diffusion coefficient. This relationship is investigated in the stationary state for the particular case of long rooms with different amounts of boundary scattering.

An experimental evaluation of the impact of scattering on sound field diffusivity.

This work provides a systematic experimental evaluation of the impact of scattering on sound field diffusivity in a proportionate medium-small sized room. A scale model is set up in many ways by increasing the amount of scattering, and detailing measurements of the reverberation time in each case. With the aid of statistical tools, the role of scattering in the process of achieving a diffuse sound field from initially non-diffuse conditions is outlined and a set of reference scattering threshold values is derived.

On the perception of speech in primary school classrooms: ranking of noise interference and of age influence.

It is well documented that the interference of noise in the classroom puts younger pupils at a disadvantage for speech perception tasks. Nevertheless, the dependence of this phenomenon on the type of noise, and the way it is realized for each class by a specific combination of intelligibility and effort have not been fully investigated. Following on a previous laboratory study on "listening efficiency," which stems from a combination of accuracy and latency measures, this work tackles the problems above to better understand the basic mechanisms governing the speech perception performance of pupils in noisy classrooms.

A numerical investigation of the Fick's law of diffusion in room acoustics.

In this paper the validity of the Fick's law of diffusion in room acoustics is investigated in the stationary state. The Fick's law, underlying the room-acoustics diffusion model, assumes a proportionality relationship between the local sound intensity and the energy density gradient, the proportionality constant being the so-called diffusion coefficient. This relationship, based on an analogy with the behavior of real particles in a scattering medium, is assessed by using a numerical tool simulating the actual dynamics of sound particles in a room.

Intelligibility, listening difficulty and listening efficiency in auralized classrooms.

In order to obtain an effective speech communication in rooms it is advisable, besides reaching the full intelligibility of words, to minimize the effort paid by the listener in the recognition of the speech material. This twofold requirement is not easily described by the current room acoustic indicators, which are mainly concerned either with a subjective rating by means of word recognition scores or with using listeners' impressions of reported listening difficulties. In this work, the problem is tackled by introducing the concept of "listening efficiency," which is defined as a combination of the accuracy of intelligibility and of the effort spent on achieving this goal.