Jan Wouters

KU Leuven | ku leuven · Department of Neurosciences

Objective: To investigate the reliability of a bilingual school-age hearing screening in four school grades based on the Digit Triplet Test (DTT) in two languages and to investigate three calculation methods for referral values in their ability to detect hearing losses and avoid false-positive results. Design and study sample: 3255 children, age...

During the COVID-19 pandemic, children worldwide experienced school closures. Several studies have detected a negative impact on reading-related skills in children who experienced these closures during the early stages of reading instruction, but the impact on the reading network in the brain has not been investigated. In the current longitudinal s...

Background Subthalamic deep brain stimulation (STN-DBS) is a well-established therapy to treat Parkinson’s disease (PD). However, the STN-DBS sub-target remains debated. Recently, a white matter tract termed the hyperdirect pathway (HDP), directly connecting the motor cortex to STN, has gained interest as HDP stimulation is hypothesized to drive DB...

Electrically evoked frequency-following responses (eFFRs) provide insight in the phase-locking ability of brainstem of cochlear-implant (CI) users. eFFRs can potentially be used to gain insight in the individual differences in the biological limitation on temporal encoding of the electrically stimulated auditory pathway, which can be inherent to th...

Purpose Attempts to use current-focussing strategies with cochlear implants (CI) to reduce neural spread-of-excitation have met with only mixed success in human studies, in contrast to promising results in animal studies. Although this discrepancy could stem from between-species anatomical and aetiological differences, the masking experiments used...

The usage of a tablet-based language-independent self-test involving the recognition of ecological sounds in background noise, the Sound Ear Check, was investigated. The results of 692 children, aged between 5 and 9 years and 4 months, recruited in seven different countries, were used to analyze the validity and the cultural independence of test. T...

Prelingual single-sided deafness (SSD) not only affects children’s hearing skills, but can also lead to speech-language delays and academic underachievement. Early cochlear implantation leads to improved spatial hearing, but the impact on language development is less studied. In our longitudinal study, we assessed the language skills of young child...

Objective Subthalamic deep brain stimulation (STN-DBS) is a neurosurgical therapy to treat Parkinson’s disease (PD). Optimal therapeutic outcomes are not achieved in all patients due to increased DBS technological complexity; programming time constraints; and delayed clinical response of some symptoms. To streamline the programming process, biomark...

Early childhood is a critical period for structural brain development as well as an important window for the identification and remediation of reading difficulties. Recent research supports the implementation of interventions in at-risk populations as early as kindergarten or first grade, yet the neurocognitive mechanisms following such interventio...

italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Objective: Electrically evoked auditory steady-state responses (EASSRs) can potentially be used as an objective measure to realize the automatic fitting of cochlear implants (CIs). They can be recorded using electroencephalography (EEG) and objectively...

Hearing aids (HA) are a fundamental component in restoring auditory function; however, they cannot completely alleviate all problems encountered by adults with hearing impairment. The aim of this study is twofold. Firstly, we assess the health-related quality of life and coping strategies of experienced HA users. Secondly, we assess whether HA user...

Purpose: Speech perception in noise is an everyday occurrence for adults and children alike. The factors that influence how well individuals cope with noise during spoken communication are not well understood, particularly in the case of children. This article aims to review the available evidence on how working memory and attention play a role i...

Auditory steady-state responses (ASSRs) are phase-locked responses of the auditory system to the envelope of a stimulus. These responses can be used as an objective proxy to assess temporal envelope processing and its related functional outcomes such as hearing thresholds and speech perception, in normal-hearing listeners, in persons with hearing i...

A cochlear implant is a neuroprosthetic device that can restore speech perception for people with severe to profound hearing loss. Because of recent evolutions, a growing number of people with a cochlear implant have useful residual acoustic hearing. While combined electro-acoustic stimulation has been shown to improve speech perception for this gr...

Some children who develop dyslexia show pre-reading auditory and speech processing difficulties. Furthermore, left auditory cortex structure might be related to family risk for dyslexia rather than to reading outcome. However, it remains unclear to what extent auditory and speech processing and auditory cortex structure mediate the relationship bet...

Early assessment of hearing aid benefit is crucial, as the extent to which hearing aids provide audible speech information predicts speech and language outcomes. A growing body of research has proposed neural envelope tracking as an objective measure of speech, particularly for individuals unable to provide reliable behavioral feedback. However, it...

A growing body of neuroimaging evidence shows that white matter can change as a result of experience and structured learning. Although the majority of previous work has used diffusion MRI to characterize such changes in white matter, diffusion metrics offer limited biological specificity about which microstructural features may be driving white mat...

Speech-in-noise perception seems aberrant in individuals with autism spectrum disorder (ASD). Potential aggravating factors are the level of linguistic skills and impairments in auditory temporal processing. Here, we investigated autistic adolescents with and without language delay as compared to non-autistic peers, and we assessed speech perceptio...

The use of two types of speech-in-noise (SPIN) assessment, namely digits-in-noise self-tests and open-set, monosyllabic word tests, to assess the SPIN understanding performance of children with cochlear implants (CI) in mainstream and special education, was investigated. The tests' feasibility and reliability and the influence of specific cognitive...

Neural processing of the speech envelope is of crucial importance for speech perception and comprehension. This envelope processing is often investigated by measuring neural synchronization to sinusoidal amplitude-modulated stimuli at different modulation frequencies. However, it has been argued that these stimuli lack ecological validity. Pulsatil...

Literacy acquisition is a complex process with genetic and environmental factors influencing cognitive and neural processes associated with reading. Previous research identified factors that predict word reading fluency (WRF), including phonological awareness (PA), rapid automatized naming (RAN), and speech-in-noise perception (SPIN). Recent theore...

The risk of insertion trauma in cochlear implantation is determined by the interplay between individual cochlear anatomy and electrode insertion mechanics. Whereas patient anatomy cannot be changed, new surgical techniques, devices for cochlear monitoring, drugs, and electrode array designs are continuously being developed and tested, to optimize t...

Intelligibility of time-compressed (TC) speech decreases with increasing speech rate. However, intelligibility can be restored by ‘repackaging’ the TC speech by inserting silences between the syllables so that the original ‘rhythm’ is restored. Although restoration of the speech rhythm affects solely the temporal envelope, it is unclear to which ex...

Speech-in-noise perception seems aberrant in individuals with autism spectrum disorder (ASD). Potential aggravating factors are level of linguistic skills and impairments in auditory temporal processing. Here, we investigated autistic adolescents with and without language delay as compared to non-autistic peers, and we assessed speech perception in...

Cochlear implant restores hearing loss through electrical stimulation of the hearing nerve from within the cochlea. Unfortunately, surgical implantation of this neuroprosthesis often traumatizes delicate intracochlear structures, resulting in loss of residual hearing and compromising hearing in noisy environments and appreciation of music. To avoid...

Two EEG experiments measured the sustained neural response to amplitude-modulated (AM) high-rate pulse trains presented to a single cochlear-implant (CI) electrode. Stimuli consisted of two interleaved pulse trains with AM rates F1 and F2 close to 80 and 120 Hz respectively, and where F2 = 1.5F1. Following Carlyon et al. (J Assoc Res Otolaryngol, 2...

Background Subthalamic deep brain stimulation (DBS) is an established therapy to treat Parkinson’s disease (PD). To maximize therapeutic outcome, optimal DBS settings must be carefully selected for each patient. Unfortunately, this is not always achieved because of: (1) increased technological complexity of DBS devices, (2) time restraints, or lack...

Advancements in intracochlear diagnostics, as well as prosthetic and regenerative inner ear therapies, rely on a good understanding of cochlear microanatomy. The human cochlea is very small and deeply embedded within the densest skull bone, making nondestructive visualization of its internal microstructures extremely challenging. Current imaging te...

To obtain combined behavioural and electrophysiological measures of pitch perception, we presented harmonic complexes, bandpass filtered to contain only high-numbered harmonics, to normal-hearing listeners. These stimuli resemble bandlimited pulse trains and convey pitch using a purely temporal code. A core set of conditions consisted of six stimul...

A growing number of studies has investigated temporal processing deficits in dyslexia. These studies largely focus on neural synchronization to speech. However, the importance of rise times for neural synchronization is often overlooked. Furthermore, targeted interventions, phonics‐based and auditory, are being developed, but little is known about...

In cochlear implant surgery, insertion of perimodiolar electrode arrays into the scala tympani can be complicated by trauma or even accidental translocation of the electrode array within the cochlea. In patients with partial hearing loss, cochlear trauma can not only negatively affect implant performance, but also reduce residual hearing function....

Objectives: Audiological rehabilitation includes sensory management, auditory training (AT), and counseling and can alleviate the negative consequences associated with (untreated) hearing impairment. AT aims at improving auditory skills through structured analytical (bottom-up) or synthetic (top-down) listening exercises. The evidence for AT to im...

Developmental dyslexia is considered to be most effectively addressed with preventive phonics-based interventions, including grapheme-phoneme coupling and blending exercises. These intervention types require intact speech perception abilities, given their large focus on exercises with auditorily presented phonemes. Yet some children with (a risk fo...

A tablet-based language-independent self-test involving the recognition of ecological sounds in background noise, the Sound Ear Check (SEC), was adapted to make it feasible for young children. Two experiments were conducted. The first experiment investigated the SEC‘s feasibility, as well as its sensitivity and specificity for detecting childhood h...

People with age-related hearing loss suffer from speech understanding difficulties, even after correcting for differences in hearing audibility. These problems are not only attributed to deficits in audibility but are also associated with changes in central temporal processing. The goal of this study is to obtain an understanding of potential alter...

Humans rely on the temporal processing ability of the auditory system to perceive speech during everyday communication. The temporal envelope of speech is essential for speech perception, particularly envelope modulations below 20 Hz. In the literature, the neural representation of this speech envelope is usually investigated by recording neural ph...

Objective: The aim of this study was to develop an open-set word recognition task in speech-weighted noise and in quiet for young children and examine age effects for open versus closed response formats. Design: Dutch monosyllabic words were presented in quiet and in stationary speech-weighted noise to 4- and 5-year-old children as well as to yo...

We describe a scalp-recorded measure of tonotopic selectivity, the "cortical onset response" (COR) and compare the results between humans and cats. The COR results, in turn, were compared with psychophysical masked-detection thresholds obtained using similar stimuli and obtained from both species. The COR consisted of averaged responses elicited by...

Different studies have suggested that during speech processing readers with dyslexia present atypical levels of neural entrainment as well as atypical functional hemispherical asymmetries in comparison with typical readers. In this study, we evaluated these differences in children and the variation with age before and after starting with formal rea...

Individuals with single-sided deafness (SSD) have no access to binaural hearing, which limits their ability to localize sounds and understand speech in noisy environments. In addition, children with prelingual SSD are at risk for neurocognitive and academic difficulties. Early cochlear implantation may lead to improved hearing outcomes by restoring...

Cochlear implant (CI) users show limited sensitivity to the temporal pitch conveyed by electric stimulation, contributing to impaired perception of music and of speech in noise. Neurophysiological studies in cats suggest that this limitation is due, in part, to poor transmission of the temporal fine structure (TFS) by the brainstem pathways that ar...

Background Deep brain stimulation (DBS) is an effective neuromodulation therapy to treat people with medication-refractory Parkinson’s disease (PD). However, the neural networks affected by DBS are not yet fully understood. Recent studies show that stimulating on different DBS-contacts using a single current source results in distinct EEG-based evo...

Hoewel de meeste kinderen vlot leren lezen, is dit niet voor iedereen het geval. Sommige kinderen ontwikkelen dyslexie, gekenmerkt door ernstige en hardnekkige problemen bij het leren lezen die in de meeste gevallen persisteren door de tijd, tot op het niveau van gevorderde lezers. Het is bekend dat de groep van personen met dyslexie atypische afwi...

Diffusion-weighted imaging studies have repeatedly shown that white matter correlates with reading throughout development. However, the neurobiological interpretation of this relationship is constrained by the limited microstructural specificity of diffusion imaging. A critical component of white matter microstructure is myelin, which can be invest...

Background: Enjoyment plays a key role in the success and feasibility of serious gaming interventions. Unenjoyable games will not be played, and in the case of serious gaming, learning will not occur. Therefore, a so-called GameFlow model has been developed, which intends to guide (serious) game developers in the process of creating and evaluating...

Speech perception in difficult listening conditions depends highly on the temporal processing ability of the auditory pathway. In the present study, we investigate the inter-subject variability of young normal-hearing listeners in the identification of time-compressed speech and how the ability to identify time-compressed speech, as assessed by the...

The visual word form area (VWFA) plays a significant role in the development of reading skills. However, the developmental course and anatomical properties of the VWFA have only limitedly been investigated. The aim of the current longitudinal MRI study was to investigate dynamic, bidirectional relations between reading, and the structure of the lef...

Recent prereading evidence demonstrates that white matter alterations are associated with dyslexia even before the onset of reading instruction. At the same time, remediation of reading difficulties is suggested to be most effective when provided as early as kindergarten, yet evidence is currently lacking on the early neuroanatomical changes associ...

Objectives Deep brain stimulation (DBS) delivered via multicontact leads implanted in the basal ganglia is an established therapy to treat Parkinson disease (PD). However, the different neural circuits that can be modulated through stimulation on different DBS contacts are poorly understood. Evidence shows that electrically stimulating the subthala...

Speech-perception testing is essential for monitoring outcomes with a hearing aid or cochlear implant (CI). However, clinical care is time-consuming and often challenging with an increasing number of clients. A potential approach to alleviating some clinical care and possibly making room for other outcome measures is to employ technologies that ass...

Diffusion-weighted imaging studies have repeatedly shown that white matter correlates with reading throughout development. However, the neurobiological interpretation of this relationship is constrained by the limited microstructural specificity of diffusion imaging. A critical component of white matter microstructure is myelin, which can be invest...

BACKGROUND Game enjoyment plays a key role in the success and feasibility of digital serious gaming interventions. Unenjoyable games will not be played and in the case of serious gaming, learning will not occur. Given this importance, a so-called GameFlow model has been developed, intending to guide (serious) game developers in the process of creat...

Different studies have suggested that language and developmental disorders such as dyslexia are associated with a disturbance of auditory entrainment and of the functional hemispheric asymmetries during speech processing. These disorders typically result from an issue in the phonological component of language that causes problems to represent and m...

Dyslexia has frequently been related to atypical auditory temporal processing and speech perception. Results of studies emphasizing speech onset cues and reinforcing the temporal structure of the speech envelope, i.e. envelope enhancement, demonstrated reduced speech perception deficits in individuals with dyslexia. The use of this strategy as audi...

Speech perception depends highly on the neural processing of the speech envelope. Several auditory processing deficits are hypothesized to result in a reduction in fidelity of the neural representation of the speech envelope across the auditory pathway. Furthermore, this reduction in fidelity is associated with supra-threshold speech processing def...

Dyslexia is targeted most effectively when (1) interventions are provided preventively, before the onset of reading instruction, and (2) remediation programs combine letter-sound training with phoneme blending. Given the growing potential of technology in educational contexts, there has been a considerable increase of letter-sound trainings embedde...

Importance Pediatric single-sided deafness (SSD) can seriously affect development, causing impaired spatial hearing skills, speech-language delays, and academic underachievement. Early cochlear implantation likely improves hearing-related outcomes, but its association with language development remains unclear. Objective To investigate whether earl...

Auditory processing is affected by advancing age and hearing loss, but the underlying mechanisms are still unclear. We investigated the effects of age and hearing loss on temporal processing of naturalistic stimuli in the auditory system. We employed a recently developed objective measure for neural phase-locking to the fundamental frequency of the...

Primary education is the incubator for learning academic skills that help children to become a literate, communicative, and independent person. Over this learning period, nonlinear and regional changes in the brain occur, but how these changes relate to academic performance, such as reading ability, is still unclear. In the current study, we analyz...

Objective The current study aimed to investigate the feasibility of the digit triplet test (DTT) as a self-test in normal-hearing children at school-entry age (5–6 years) compared to an administrator-controlled test. Design and study sample Thirty-seven first grade elementary school children took part in this study. Next to a pure-tone screening,...

We describe a non-invasive electrophysiological (EEG) measure of tonotopic selectivity and compare the results between humans and cats. Sequences of 50-ms tone-burst probes were presented at 1-second intervals against a continuous noise masker, and the averaged cortical onset response (COR) to the probe was measured using EEG electrodes placed on t...

Objective: 'F0 tracking' is a novel method that investigates neural processing of the fundamental frequency of the voice (f0) in continuous speech. Using linear modelling, a feature that reflects the f0 of a presented speech stimulus is predicted from neural EEG responses. The correlation between the predicted and the 'actual' f0 feature is a meas...

Developmental dyslexia is most commonly associated with phonological processing difficulties. However, children with dyslexia may experience poor speech-in-noise perception as well. Although there is an ongoing debate whether a speech perception deficit is inherent to dyslexia or acts as an aggravating risk factor compromising learning to read indi...