Triphasic pulse stimulation can prevent unpleasant facial nerve stimulation in cochlear implant users. Using electromyographic measurements on facial nerve effector muscles, previous studies have... Show moreTriphasic pulse stimulation can prevent unpleasant facial nerve stimulation in cochlear implant users. Using electromyographic measurements on facial nerve effector muscles, previous studies have shown that biphasic and triphasic pulse stimulations produce different input-output functions. However, little is known about the intracochlear effects of triphasic stimulation and how these may contribute to the amelioration of facial nerve stimulation.The present study used a computational model of implanted human cochleae to investigate the effect of pulse shape on the intracochlear spread of excitation. Biphasic and triphasic pulse stimulations were simulated from three different cochlear implant electrode contact positions. To validate the model results, experimental spread of excitation measurements were conducted with biphasic and triphasic pulse stimulation from three different electrode contact positions in 13 cochlear implant users.The model results depict differences between biphasic and triphasic pulse stimulations depending on the position of the stimulating electrode contact. While biphasic and triphasic pulse stimulations from a medial or basal electrode contact caused similar extents of neural excitation, differences between the pulse shapes were observed when the stimulating contact was located in the cochlear apex. In contrast, the experimental results showed no difference between the biphasic and triphasic initiated spread of excitation for any of the tested contact positions. The model was also used to study responses of neurons without peripheral processes to mimic the effect of neural degeneration. For all three contact positions, simulated degeneration shifted the neural responses towards the apex. Biphasic pulse stimulation showed a stronger response with neural degeneration compared to without degeneration, while triphasic pulse stimulation showed no difference.As previous measurements have demonstrated an ameliorative effect of triphasic pulse stimulation on facial nerve stimulation from medial electrode contact positions, the results imply that a complementary effect located at the facial nerve level must be responsible for reducing facial nerve stimulation. Show less
Objectives: This study compared the performance of a dynamic partial tripolar cochlear implant speech encoding strategy termed dynamic current focusing (DCF) to monopolar stimulation (MP) using... Show moreObjectives: This study compared the performance of a dynamic partial tripolar cochlear implant speech encoding strategy termed dynamic current focusing (DCF) to monopolar stimulation (MP) using spectro-temporal, temporal, and speech-in-noise recognition testing. Design: DCF is a strategy that utilizes tripolar or high partial tripolar stimulation at threshold level and increases loudness by slowly widening current spread towards most comfortable level. Thirteen cochlear implant users were fitted with DCF and a non-steered MP matched on pulse rate, pulse width, and active electrodes. Nine participants completed the single-blinded within-subject crossover trial. Repeated testing consisted of four sessions. Strategies were allocated in a DCF-MP-DCF-MP or MP-DCF-MP-DCF design. Three-week adaptation periods ended with a test session in which speech-in-noise recognition (matrix speech-in-noise sentence test), spectro-temporal ripple tests (SMRT and STRIPES) and a temporal amplitude modulation detection test were conducted. All participants recorded their subjective experiences with both strategies using the Speech, Spatial and Qualities of Hearing Scale questionnaire. Results: Participants' SMRT thresholds improved 0.40 ripples per octave (p = 0.02, Bonferroni-corrected: p = 0.1) with DCF over MP at 65 dB SPL. No significant differences between the strategies were found on speech-in-noise recognition at conversational (65 dB SPL) and soft (45 dB SPL) loudness levels, temporal testing, STRIPES, or the SMRT at 45 dB SPL. After Bonferroni correction, a learning effect remained on the matrix speech-in-noise sentence test at both loudness levels (65 dB SPL: p = 0.01; 45 dB SPL: p = 0.02). There was no difference in learning effects over time between DCF and MP. Similarly, no significant differences were found in subjective experience on the Speech, Spatial and Qualities of Hearing Scale questionnaire. DCF reduced average battery life by 48% (5.1 hours) (p < 0.001) compared to MP. Conclusions: DCF may improve spectral resolution over MP at comfortable loudness (65 dB SPL) in cochlear implant users. However, the evidence collected in this study was weak and the significant result disappeared after Bonferroni correction. Also, not all spectral tests revealed this improvement. As expected, battery life was reduced for DCF. Although the current study is limited by its small sample size, considering previous studies, DCF does not consistently improve speech recognition in noise over MP strategies. Show less
Hearing is an important element for the human wellbeing. It is, therefore, essential to rehabilitate hearing loss adequately. In case of severe hearing loss, for which a regular hearing aid does... Show moreHearing is an important element for the human wellbeing. It is, therefore, essential to rehabilitate hearing loss adequately. In case of severe hearing loss, for which a regular hearing aid does not work sufficiently, a cochlear implant (CI) can be a solution. A CI is a device that transmits sound directly to the auditory nerve by electrically stimulating the nerve through an electrode array in the cochlea. These electrical stimuli are perceived as sound. The CI also has a telemetry function, which measures the activity of the auditory nerve. The measured activity, called 'eCAP', provides information about the functioning of the CI and the auditory nerve.This thesis describes our study to the relevance and clinical applicability of the eCAP. We investigated how (under which conditions) eCAPs must be measured for potential clinical use. We therefore evaluated common measurement techniques and proposed some improvements. We also developed completely new eCAP measurement techniques. The thesis provided building blocks for a better understanding of how the CI works and for better fitting the CI to the needs of the individual patient. Show less
Objective: We sought to validate our proposed tool for estimating channel discrimination of cochlear implant (CI) users along the full electrode array and to assess associations between place-pitch... Show moreObjective: We sought to validate our proposed tool for estimating channel discrimination of cochlear implant (CI) users along the full electrode array and to assess associations between place-pitch discrimination and speech perception. Design: In two tests, participants identified one stimulus (probe) as the odd-one-out compared with two reference stimuli. Probe stimuli were evoked using dual electrode stimulation characterised by the current steering coefficient alpha. The first test measured psychometric functions (PFs) on pre-defined contacts, with just a noticeable difference (JND alpha) as the outcome variable. The second test estimated channel discrimination on the full electrode array, yielding a discrimination score of D alpha. We measured speech perception as free-field consonant-vowel-consonant phoneme recognition scores. Study sample: We included 25 adults with at least 6 months of CI experience. Results: JND alpha and D alpha scores measured on the same contact correlated significantly (r(s) = 0.64, p < 0.001). Mean JND alpha and speech perception scores showed significant relationships in quiet and in noise. Conclusions: D alpha correlated strongly with JND alpha scores obtained with the PFs. For poor performers, the full-array test may underestimate JND alpha. The full-array pitch discrimination test could be a helpful clinical tool, such as for fitting regions of lesser pitch discrimination ability. Show less
ObjectiveWe sought to validate our proposed tool for estimating channel discrimination of cochlear implant (CI) users along the full electrode array and to assess associations between place-pitch... Show moreObjectiveWe sought to validate our proposed tool for estimating channel discrimination of cochlear implant (CI) users along the full electrode array and to assess associations between place-pitch discrimination and speech perception.DesignIn two tests, participants identified one stimulus (probe) as the odd-one-out compared with two reference stimuli. Probe stimuli were evoked using dual electrode stimulation characterised by the current steering coefficient α. The first test measured psychometric functions (PFs) on pre-defined contacts, with just a noticeable difference (JNDα) as the outcome variable. The second test estimated channel discrimination on the full electrode array, yielding a discrimination score of Dα. We measured speech perception as free-field consonant-vowel-consonant phoneme recognition scores.Study sampleWe included 25 adults with at least 6 months of CI experience.ResultsJNDα and Dα scores measured on the same contact correlated significantly (rs = 0.64, p < 0.001). Mean JNDα and speech perception scores showed significant relationships in quiet and in noise.ConclusionsDα correlated strongly with JNDα scores obtained with the PFs. For poor performers, the full-array test may underestimate JNDα. The full-array pitch discrimination test could be a helpful clinical tool, such as for fitting regions of lesser pitch discrimination ability. Show less
Dit proefschrift is gericht op het onderzoeken van verschillende aspecten van de huidige revalidatie rondomgehoorverlies. In de verschillende hoofdstukken wordt ingegaan op de selectiecriteria voor... Show moreDit proefschrift is gericht op het onderzoeken van verschillende aspecten van de huidige revalidatie rondomgehoorverlies. In de verschillende hoofdstukken wordt ingegaan op de selectiecriteria voor volwassen CI-kandidaten (hoofdstuk 2 en 3), de taalontwikkeling bij kinderen met een ABI (hoofdstuk 4), enverschillende ontwikkelingsuitkomsten na revalidatie voor kinderen met gehoorverlies, zoals het sociaalemotioneel functioneren (hoofdstuk 5) en het opleidingsniveau (hoofdstuk 6). Show less
The main aim of this computational modelling study was to test the validity of the hypothesis that sensitivity to the polarity of cochlear implant stimulation can be interpreted as a measure of... Show moreThe main aim of this computational modelling study was to test the validity of the hypothesis that sensitivity to the polarity of cochlear implant stimulation can be interpreted as a measure of neural health. For this purpose, the effects of stimulus polarity on neural excitation patterns were investigated in a volume conduction model of the implanted human cochlea, which was coupled with a deterministic active nerve fibre model based on characteristics of human auditory neurons. The nerve fibres were modelled in three stages of neural degeneration: intact, with shortened peripheral terminal nodes and with complete loss of the peripheral processes. The model simulated neural responses to monophasic, biphasic, triphasic and pseudomonophasic pulses of both polarities. Polarity sensitivity was quantified as the so-called polarity effect (PE), which is defined as the dB difference between cathodic and anodic thresholds. Results showed that anodic pulses mostly excited the auditory neurons in their central axons, while cathodic stimuli generally excited neurons in their peripheral processes or near their cell bodies. As a consequence, cathodic thresholds were more affected by neural degeneration than anodic thresholds. Neural degeneration did not have a consistent effect on the modelled PE values, though there were notable effects of electrode contact insertion angle and distance from the modiolus. Furthermore, determining PE values using charge-balanced multiphasic pulses as approximations of monophasic stimuli produced different results than those obtained with true monophasic pulses, at a degree that depended on the specific pulse shape; in general, pulses with lower secondary phase amplitudes showed polarity sensitivities closer to those obtained with true monophasic pulses. The main conclusion of this study is that polarity sensitivity is not a reliable indicator of neural health; neural degeneration affects simulated polarity sensitivity, but its effect is not consistently related to the degree of degeneration. Polarity sensitivity is not simply a product of the state of the neurons, but also depends on spatial factors.(c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ) Show less
Objectives: The primary objective of this study is to identify the biographic, audiologic, and electrode position factors that influence speech perception performance in adult cochlear implant (CI)... Show moreObjectives: The primary objective of this study is to identify the biographic, audiologic, and electrode position factors that influence speech perception performance in adult cochlear implant (CI) recipients implanted with a device from a single manufacturer. The secondary objective is to investigate the independent association of the type of electrode (precurved or straight) with speech perception. Design: In a cross-sectional study design, speech perception measures and ultrahigh-resolution computed tomography scans were performed in 129 experienced CI recipients with a postlingual onset of hearing loss. Data were collected between December 2016 and January 2018 in the Radboud University Medical Center, Nijmegen, the Netherlands. The participants received either a precurved electrode (N = 85) or a straight electrode (N = 44), all from the same manufacturer. The biographic variables evaluated were age at implantation, level of education, and years of hearing loss. The audiometric factors explored were preoperative and postoperative pure-tone average residual hearing and preoperative speech perception score. The electrode position factors analyzed, as measured from images obtained with the ultrahigh-resolution computed tomography scan, were the scalar location, angular insertion depth of the basal and apical electrode contacts, and the wrapping factor (i.e., electrode-to-modiolus distance), as well as the type of electrode used. These 11 variables were tested for their effect on three speech perception outcomes: consonant-vowel-consonant words in quiet tests at 50 dB SPL (CVC50) and 65 dB SPL (CVC65), and the digits-in-noise test. Results: A lower age at implantation was correlated with a higher CVC50 phoneme score in the straight electrode group. Other biographic variables did not correlate with speech perception. Furthermore, participants implanted with a precurved electrode and who had poor preoperative hearing thresholds performed better in all speech perception outcomes than the participants implanted with a straight electrode and relatively better preoperative hearing thresholds. After correcting for biographic factors, audiometric variables, and scalar location, we showed that the precurved electrode led to an 11.8 percentage points (95% confidence interval: 1.4-20.4%; p = 0.03) higher perception score for the CVC50 phonemes compared with the straight electrode. Furthermore, contrary to our initial expectations, the preservation of residual hearing with the straight electrode was poor, as the median preoperative and the postoperative residual hearing thresholds for the straight electrode were 88 and 122 dB, respectively. Conclusions: Cochlear implantation with a precurved electrode results in a significantly higher speech perception outcome, independent of biographic factors, audiometric factors, and scalar location. Show less
Empathy enables people to share, understand, and show concern for others' emotions. However, this capacity may be more difficult to acquire for children with hearing loss, due to limited social... Show moreEmpathy enables people to share, understand, and show concern for others' emotions. However, this capacity may be more difficult to acquire for children with hearing loss, due to limited social access, and the effect of hearing on empathic maturation has been unexplored. This four-wave longitudinal study investigated the development of empathy in children with and without hearing loss, and how this development is associated with early symptoms of psychopathology. Seventy-one children with hearing loss and cochlear implants (CI), and 272 typically-hearing (TH) children, participated (aged 1-5 years at Time 1). Parents rated their children's empathic skills (affective empathy, attention to others' emotions, prosocial actions, and emotion acknowledgment) and psychopathological symptoms (internalizing and externalizing behaviors). Children with CI and TH children were rated similarly on most of the empathic skills. Yet, fewer prosocial actions were reported in children with CI than in TH children. In both groups, affective empathy decreased with age, while prosocial actions and emotion acknowledgment increased with age and stabilized when children entered primary schools. Attention to emotions increased with age in children with CI, yet remained stable in TH children. Moreover, higher levels of affective empathy, lower levels of emotion acknowledgment, and a larger increase in attention to emotions over time were associated with more psychopathological symptoms in both groups. These findings highlight the importance of social access from which children with CI can learn to process others' emotions more adaptively. Notably, interventions for psychopathology that tackle empathic responses may be beneficial for both groups, alike. Show less
Objectives: The aim of this study is to report on our preliminary experience with Transimpedance Matrix (TIM)-measurement for the detection of cochlear implant electrode tip foldovers compared with... Show moreObjectives: The aim of this study is to report on our preliminary experience with Transimpedance Matrix (TIM)-measurement for the detection of cochlear implant electrode tip foldovers compared with intraoperative imaging in patients implanted with the slim modiolar electrode (SME). Study Design: Proof of concept study. Setting: Tertiary university referral center. Patients: Twenty five ears (in 22 patients) implanted consecutively with the SME. Intervention(s): Following cochlear implantation, intraoperative TIM-measurement and fluoroscopy were performed. One week postoperatively, the electrode position was evaluated using Computed Tomography (CT)-imaging. Main Outcome Measures: Electrode array tip foldover. Results: Electrode array tip foldover occurred in three of the 25 cochlear implantations performed (12%). In each case, the foldover was detected by both TIM and fluoroscopy, leading to reposition and correct intracochlear placement of the array. Conclusions: TIM-measurement is a promising method for the intraoperative detection of an electrode array tip foldover. The TIM-tool with intuitive heatmap display is easy to use, fast, and readily available to clinics using TIM-software in the operating theatre. Show less
Objectives: Phantom electrode stimulation was developed for cochlear implant (CI) systems to provide a lower pitch percept by stimulating more apical regions of the cochlea, without inserting the... Show moreObjectives: Phantom electrode stimulation was developed for cochlear implant (CI) systems to provide a lower pitch percept by stimulating more apical regions of the cochlea, without inserting the electrode array deeper into the cochlea. Phantom stimulation involves simultaneously stimulating a primary and a compensating electrode with opposite polarity, thereby shifting the electrical field toward the apex and eliciting a lower pitch percept. The current study compared the effect sizes (in shifts of place of excitation) of multiple phantom configurations by matching the perceived pitch with phantom stimulation to that perceived with monopolar stimulation. Additionally, the effects of electrode location, type of electrode array, and stimulus level on the perceived pitch were investigated. Design: Fifteen adult advanced bionics CI users participated in this study, which included four experiments to eventually measure the shifts in place of excitation with five different phantom configurations. The proportions of current delivered to the compensating electrode, expressed as sigma, were 0.5, 0.6, 0.7, and 0.8 for the symmetrical biphasic pulses (SBC0.5, SBC0.6, SBC0.7, and SBC0.8) and 0.75 for the pseudomonophasic pulse shape (PSA(0.75)). A pitch discrimination experiment was first completed to determine which basal and apical electrode contacts should be used for the subsequent experiments. An extensive loudness balancing experiment followed where both the threshold level (T-level) and most comfortable level (M-level) were determined to enable testing at multiple levels of the dynamic range. A pitch matching experiment was then performed to estimate the shift in place of excitation at the chosen electrode contacts. These rough shifts were then used in the subsequent experiment, where the shifts in place of excitation were determined more accurately. Results: Reliable data were obtained from 20 electrode contacts. The average shifts were 0.39, 0.53, 0.64, 0.76, and 0.53 electrode contacts toward the apex for SBC0.5, SBC0.6, SBC0.7, SBC0.8, and PSA(0.75), respectively. When only the best configurations per electrode contact were included, the average shift in place of excitation was 0.92 electrode contacts (range: 0.25 to 2.0). While PSA(0.75)leads to equal results as the SBC configurations in the apex, it did not result in a significant shift at the base. The shift in place of excitation was significantly larger at the apex and with lateral wall electrode contacts. The stimulus level did not affect the shift. Conclusions: Phantom stimulation results in significant shifts in place of excitation, especially at the apical part of the electrode array. The phantom configuration that leads to the largest shift in place of excitation differs between subjects. Therefore, the settings of the phantom electrode should be individualized so that the phantom stimulation is optimized for each CI user. The real added value to the sound quality needs to be established in a take-home trial. Show less
Objective: The reliability of the electrically evoked compound action potential (eCAP) threshold depends on its precision and accuracy. The precision of the eCAP threshold reflects its variability,... Show moreObjective: The reliability of the electrically evoked compound action potential (eCAP) threshold depends on its precision and accuracy. The precision of the eCAP threshold reflects its variability, while the accuracy of the threshold shows how close it is to the actual value. The objective of this study was to determine the test/retest variability of the eCAP threshold in Advanced Bionics cochlear implant users, which has never been reported before. We hypothesized that the test/retest variability is dependent on the presence of random noise in the recorded eCAP waveforms. If this holds true, the recorded error should be reduced by approximately the square-root of the number of averages. As secondary objectives, we assessed the effects of the slope of the amplitude growth function (AGF), cochlear location, and eCAP threshold on eCAP threshold precision. We hypothesized that steeper slopes should result in better precision of the linearly extrapolated eCAP threshold. As other studies have shown that apical regions have steeper slopes and larger eCAPs, we recorded eCAPs in three different cochlear locations. The difference of the precision between two commonly applied stimulus-artifact reduction paradigms on eCAP threshold precision was compared, namely averaging of alternating stimulus polarities (AP averaging) and forward masking (FM). FM requires the addition of more waveforms than AP averaging, and hence we expected FM to have lower precision than AP.Design: This was an unmasked, descriptive, and observational study with a cross-over (repeated measures) design that included 13 subjects. We recorded eCAPs on three electrode contacts: in the base, middle, and apex of the cochlea at 10 stimulus intensities. Per stimulus level, 256 eCAP waveforms were recorded. eCAP thresholds were determined by constructing AGFs and linear extrapolation to zero-amplitude. The precision of the eCAP threshold was calculated as the SD using a Monte Carlo simulation, as a function of the number of waveform averages.Results: The SD of the eCAP threshold was reduced by approximately the square root of two when the number of averages in the eCAP waveforms was doubled. The precision was significantly better when the slope of the AGF was steeper and was more favorable in the cochlear base than in the apex. Precision was better when AP averaging was used. Absolute eCAP threshold did not significantly affect precision. At the default number of 32 waveform averages in the Advanced Bionics system, we report a median SD of the eCAP threshold of 2 to 3 mu A, with a range of 1 to 11 mu A across the cochlea. Previous studies have shown that the total error, based on the 95% confidence bounds of the linear extrapolation, can be as high as -260 to +120 mu A.Conclusions: The median variability in the eCAP threshold proved to be small compared with the total variability introduced by the linear extrapolation method. Yet there was substantial intersubject variability. Therefore, we recommend monitoring the SD during eCAP recording to facilitate informed decisions when to terminate waveform collection. From a precision perspective, AP averaging is preferable over FM as it has better precision, while fewer recordings are needed, making it the more time-efficient method of the two. Show less
Objective: To test the channel discrimination of cochlear implant (CI) users along all contacts of the electrode array and assess whether this is related to speech perception.Design: CI recipients... Show moreObjective: To test the channel discrimination of cochlear implant (CI) users along all contacts of the electrode array and assess whether this is related to speech perception.Design: CI recipients were tested with a custom-made channel discrimination test. They were asked to distinguish a target stimulus from two reference stimuli in a three-alternative forced choice (3AFC) task. The target stimulus was evoked using current steering, with current steering coefficients () of 1, 0.5 and 0.25. The test provided a discrimination score (D) for each electrode contact along the array.Study sample: Thirty adults implanted with a CI from Advanced Bionics.Results: Large variations in D scores were observed, both across the electrode array and between subjects. Statistical analysis revealed a significant channel-to-channel variability in D score (p<0.01). Further, there was a significant relationship between subjects' D scores and their speech perception in quiet (p<0.001).Conclusions: The large variations in D score emphasise the importance of testing pitch discrimination across the complete electrode array. The relationship between D score and speech perception indicates that pitch discrimination might be a contributing factor to the performance of individual implant users. Show less
Objectives: In an attempt to improve spectral resolution and speech intelligibility, several current focusing methods have been proposed to increase spatial selectivity by decreasing intracochlear... Show moreObjectives: In an attempt to improve spectral resolution and speech intelligibility, several current focusing methods have been proposed to increase spatial selectivity by decreasing intracochlear current spread. For example, tripolar stimulation administers current to a central electrode and uses the two flanking electrodes as the return pathway, creating a narrower intracochlear electrical field and hence increases spectral resolution when compared with monopolar (MP) stimulation. However, more current is required, and in some patients, specifically the ones with high electrode impedances, full loudness growth cannot be supported because of compliance limits. The present study describes and analyses a new loudness encoding approach that uses tripolar stimulation near threshold and gradually broadens the excitation (by decreasing compensation coefficient sigma) to increase loudness without the need to increase overall current. It is hypothesized that this dynamic current focusing (DCF) strategy increases spatial selectivity, especially at lower loudness levels, while maintaining maximum selectivity at higher loudness levels, without reaching compliance limits.Design: Eleven adult cochlear implant recipients with postlingual hearing loss, with at least 9 months of experience with their HiRes90K implant, were selected to participate in this study. Baseline performance regarding speech intelligibility in noise (Dutch matrix sentence test), spectral ripple discrimination at 45 and 65 dB, and temporal modulation detection thresholds were assessed using their own clinical program, fitted on a Harmony processor. Subsequently, the DCF strategy was fitted on a research Harmony processor. Threshold levels were determined with sigma = 0.8, which means 80% of current is returned to the flanking electrodes and the remaining 20% to the extracochlear ground electrode. Instead of increasing overall pulse magnitude, sigma was decreased to determine most comfortable loudness. After 2 to 3hr of adaptation to the research strategy, the same psychophysical measures were taken.Results: At 45 dB, average spectral ripple scores improved significantly from 2.4 ripples per octave with their clinical program to 3.74 ripples per octave with the DCF strategy (p = 0.016). Eight out of 11 participants had an improved spectral resolution at 65 dB. Nevertheless, no significant difference between DCF and MP was observed at higher presentation levels. Both speech-in-noise and temporal modulation detection thresholds were equal for MP and DCF strategies. Subjectively, 2 participants preferred the DCF strategy over their own clinical program, 2 preferred their own strategy, while the majority of the participants had no preference. Battery life was decreased and ranged from 1.5 to 4hr.Conclusions: The DCF strategy gives better spectral resolution, at lower loudness levels, but equal performance on speech tests. These outcomes warrant for a longer adaptation period to study long-term outcomes and evaluate if the outcomes in the ripple tests transfer to the speech scores. Further research, for example, with respect to fitting rules and reduction of power consumption, is necessary to make the DCF strategy suitable for routine clinical application. Show less
The aim of this thesis was to study the link between hearing loss, language skills, and social functioning in deaf and hard of hearing (DHH) children. Sufficient language skills are an... Show moreThe aim of this thesis was to study the link between hearing loss, language skills, and social functioning in deaf and hard of hearing (DHH) children. Sufficient language skills are an essential prerequisite to develop appropriate communication skills, in order to join in conversations with others. Both their hearing loss and their diminished communication skills prevent DHH children from learning by observing their surroundings (incidental learning). As a result, DHH children showed more difficulty in understanding others’ thoughts and wishes (Theory of Mind or ToM). DHH teenagers reported to have difficulties with understanding others’ emotions and showed lower levels of prosocial behavior. Higher communication skills, but not language skills, were related to better ToM development and higher empathic abilities. Second, the role of early identification and intervention of hearing loss on the social-emotional development of DHH children was studied. This was illustrated in a longitudinal study showing that early cochlear implantation resulted in higher language and communication skills. In turn, these improved skills prevented the development of early signs of psychopathology. To conclude, this thesis shows that in order to stimulate the social-emotional development of DHH children, their opportunities for incidental learning have to be increased. Show less
Beek, F.B. van der; Briaire, J.J.; Marel, K.S. van der; Verbist, B.M.; Frijns, J.H.M. 2016
