Bimodal Condition Research Articles

From Bimodal Hearing to Sequential Bilateral Cochlear Implantation in Children-A Within-Subject Comparison.

To evaluate the performance changes after sequential bilateral cochlear implantation in a pediatric population of bimodal cochlear implant (CI) users. To evaluate the factors which influence the parental and recipient decision to discontinue hearing aid use and seek a second implant. Retrospective case review, within-subject comparison. Tertiary referral center. Thirty-one pediatric (<18 yr) bimodal CI users who underwent sequential bilateral CI. Sequential bilateral CI. Parental and/or recipient's reasons for discontinuing their hearing aid and pursuing a second implant, device usage from datalogs, speech understanding in the bimodal and bilateral CI condition. Parents/patients were motivated to pursue sequential bilateral CI based on their positive performance with CI1, the expectation of further improvement with a second CI, and the prospect of having a second independently functional ear. In the bimodal condition, mean word recognition score (WRS), sentence recognition in quiet (SIQ), and sentence recognition in noise (SIN) scores were 87.4, 97.3, and 92.9% respectively. At 1-year post-sequential bilateral CI, the mean WRS, SIQ, and SIN score were 92.7, 98.7, and 97.7%, respectively. The improvement in bilateral CI speech scores compared with bimodal scores was statistically significant for WRS (p = 0.015). A ceiling effect limited the ability to detect further meaningful differences on speech perception testing. The bilateral CI condition demonstrates equivalent or slightly superior performance compared with the bimodal condition. Several non-speech benefits were elicited from parents as reasons for pursuing a second implant. Close monitoring of the residual acoustic hearing, inquiring about the perceived benefits provided by the HA, and early counseling regarding the potential for sequential bilateral CI are important aspects in determining if and when a second implant is indicated.

Cochlear Implantation in Children with Single-Sided Deafness.

To describe our experience with children undergoing unilateral cochlear implantation (CI) for treatment of single-sided deafness (SSD). Retrospective case series. A retrospective case review from a tertiary referral center involving 14 pediatric patients (<18 years) with SSD who underwent unilateral CI. Speech perception testing in quiet and noise in the CI-only and bimodal conditions with at least 1 year of device use and device usage from data logs represent the main outcome measures. The mean age at CI was 5.0 years (median 4.4, range 1.0-11.8 years). The mean duration of deafness was 3.0 years (median 2.4, range 0.6-7.0 years). Mean follow-up was 3.4 years. Speech perception testing with a minimum of 1 year post-CI was available in eight patients. The mean word recognition scores (WRS) in the CI-only condition was 56%; a significant improvement from baseline. Testing in background noise with spatially separated speech and noise revealed that patients scored as well or better with the CI-on versus CI-off in all conditions and in no cases was interference from the CI noted. Data logs were reviewed for device usage which revealed an average use of 6.5 hr/d. Cochlear implantation is a viable treatment option for pediatric SSD in this self-selected cohort. Open-set speech and improvement in background noise can be achieved. Careful patient selection and thorough counseling on expectations is paramount to achieving successful outcomes. IV Laryngoscope, 131:E271-E277, 2021.

Bimodal stimulation in children with inner ear malformation: One side cochlear implant and contralateral auditory brainstem implant.

To determine audiological outcomes of children who use a cochlear implant (CI) in one ear and an auditory brainstem implant (ABI) in the contralateral ear. Retrospective case review. Tertiary referral hospital. Twelve children followed with CI and contralateral auditory brainstem implant (ABI) by Hacettepe University Department of Otorhinolaryngology and Audiology in Turkey. All children were diagnosed with different inner ear malformations with cochlear nerve aplasia/hypoplasia. CI was planned in the ear with better sound detection during behavioural testing with inserted ear phones and with better CN as seen on MRI. Due to the limited auditory and speech progress with the cochlear implant, ABI was performed on the contralateral ear in all subjects. Audiological performance and auditory perception skills of children with cochlear nerve deficiency (CND) who use bimodal electrical stimulation with CI and contralateral ABI. Mean age of the subjects was 84.00±33.94months. Age at CI surgery and ABI surgery was 25.00±10.98months and 41.50±16.14months, respectively. However, hearing thresholds only with CI and only with ABI did not reveal significant difference, and auditory perception scores improved with bimodal stimulation. The MAIS scores were significantly improved from unilateral CI to bimodal stimulation (P=.002). Pattern perception and word recognition scores were significantly higher with the bimodal condition when compared to CI only and ABI only conditions. Children with CND showed better performance with CI and contralateral ABI combined. Depending on the audiological and radiological results, bimodal stimulation should be advised for children with CND.

Learning of bimodal versus unimodal signals in restrained bumble bees.

Similar to animal communication displays, flowers emit complex signals that attract pollinators. Signal complexity could lead to higher cognitive load for pollinators, impairing performance, or might benefit them by facilitating learning, memory and decision making. Here, we evaluated learning and memory in foragers of the bumble bee Bombus impatiens trained to simple (unimodal) versus complex (bimodal) signals under restrained conditions. Use of a proboscis extension response protocol enabled us to control the timing and duration of stimuli presented during absolute and differential learning tasks. Overall, we observed broad variation in performance under the two conditions, with bees trained to compound bimodal signals learning and remembering as well as, better than or more poorly than bees trained to unimodal signals. Interestingly, the outcome of training was affected by the specific colour-odour combination. Among unimodal stimuli, the performance with odour stimuli was higher than with colour stimuli, suggesting that olfactory signals played a more significant role in the compound bimodal condition. This was supported by the fact that after 24 h, most bimodal-treatment bees responded to odour but not visual stimuli. We did not observe differences in latency of response, suggesting that signal composition affected decision accuracy, not speed. We conclude that restrained bumble bee workers exhibit broad variation of responses to bimodal stimuli and that components of the bimodal signal may not be used equivalently. The analysis of bee performance under restrained conditions enables accurate control of the multimodal stimuli provided to individuals and to study the interaction of individual components within a compound.

Perceiving your hand moving: BOLD suppression in sensory cortices and the role of the cerebellum in the detection of feedback delays.

Sensory consequences of self-generated as opposed to externally generated movements are perceived as less intense and lead to less neural activity in corresponding sensory cortices, presumably due to predictive mechanisms. Self-generated sensory inputs have been mostly studied in a single modality, using abstract feedback, with control conditions not differentiating efferent from reafferent feedback. Here we investigated the neural processing of (a) naturalistic action-feedback associations of (b) self-generated versus externally generated movements, and (c) how an additional (auditory) modality influences neural processing and detection of delays. Participants executed wrist movements using a passive movement device (PMD) as they watched their movements in real time or with variable delays (0-417 ms). The task was to judge whether there was a delay between the movement and its visual feedback. In the externally generated condition, movements were induced by the PMD to disentangle efferent from reafferent feedback. Half of the trials involved auditory beeps coupled to the onset of the visual feedback. We found reduced BOLD activity in visual, auditory, and somatosensory areas during self-generated compared with externally generated movements in unimodal and bimodal conditions. Anterior and posterior cerebellar areas were engaged for trials in which action-feedback delays were detected for self-generated movements. Specifically, the left cerebellar lobule IX was functionally connected with the right superior occipital gyrus. The results indicate efference copy-based predictive mechanisms specific to self-generated movements, leading to BOLD suppression in sensory areas. In addition, our results support the cerebellum's role in the detection of temporal prediction errors during our actions and their consequences.

Effects of Bimodal and Bilateral Cochlear Implant Use on a Nonauditory Working Memory Task: Reading Span Tests Over 2 Years Following Cochlear Implantation.

Purpose A growing body of evidence indicates that treatment of hearing loss by provision of hearing aids leads to improvements in auditory and visual working memory. The purpose of this study was to assess whether similar working memory benefits are observed following provision of cochlear implants (CIs). Method Fifteen adults with postlingually acquired severe bilateral sensorineural hearing loss completed the prospective longitudinal study. Participants were candidates for bilateral cochlear implantation with some aidable hearing in each ear. Implantation surgeries were carried out sequentially, approximately 1 year apart. Working memory was measured with the visual Reading Span Test (Daneman & Carpenter, 1980) at 5 time points: pre-operatively following a 6-month bilateral hearing aid trial, after 6 and 12 months of bimodal (CI plus contralateral hearing aid) listening experience following the 1st CI surgery and activation, and again after 6 and 12 months of bilateral CI listening experience following the 2nd CI surgery and activation. Results Compared to the preoperative baseline, CI listening experience yielded significant improvements in participants' ability to recall test words in the correct serial order after 12 months in the bimodal condition. Individual performance outcomes were variable, but almost all participants showed increases in task performance over the course of the study. Conclusions These results suggest that, similar to appropriate interventions with hearing aids, treatment of hearing loss with CIs can yield working memory benefits. A likely mechanism is the freeing of cognitive resources previously devoted to effortful listening.

Comparison of bimodal benefit for the use of DSL v5.0 and NAL-NL2 in cochlear implant listeners

Objective: For a group of bimodal subjects with moderate to severe hearing loss contralateral to the cochlear implant (CI), the bimodal benefit of the hearing aid (HA) gain prescriptions DSL v5.0, NAL-NL2 and the recipients’ own gain setting were assessed.Design: Speech perception in quiet and in noise as well as self-reported ratings of benefit were determined for all three gain-settings. Speech tests were performed in the bimodal, the HA alone and the CI alone condition. The bimodal benefit was assessed for each prescription as the difference score of the bimodal condition and the better ear.Study Sample: Twenty adults with post-lingual hearing loss.Results: Speech perception with DSL v5.0 was significantly higher compared to NAL-NL2 and the own prescription in both quiet and noise. The median bimodal benefit was highest for DSL v5.0 with an average of 15 percentage points for both words in quiet and sentences in noise.Conclusions: DSL v5.0 and NAL-NL2 are both suitable for HA fitting in bimodal users. For subjects with moderate to severe hearing loss and HA experience contralateral to the implanted side, DSL v5.0 may provide better speech perception and bimodal benefit.

Communication of Visual and Auditory Information and The Coordination of Team Task Performance

Due to lack of visual or auditory perceptual information, many tasks require interpersonal coordination and teaming. Dyadic verbal and/or auditory communication typically results in the two people becoming informationally coupled. This experiment examined coupling by using a two-person remote navigation task where one participant blindly drove a remote-controlled car while another participant provided auditory, visual, or a combination of both cues (bimodal). Under these conditions, we evaluated performance using easy, moderate, and hard task difficulties. We predicted that the visual condition would have higher performance measures overall, and the bimodal condition would have higher performance as difficulty increased. Results indicated that visual coupling performs better overall compared to auditory coupling and that bimodal coupling showed increased performance as task difficulty went from moderate to hard. When auditory coupling occurs, the frequency at which teams communicate affects performance— the faster teams spoke, the better they performed, even with visual communication available.

Together But Different: The Subgenomes of the Bimodal Eleutherine Karyotypes Are Differentially Organized.

Bimodal karyotypes are characterized by the presence of two sets of chromosomes of contrasting size. Eleutherine bulbosa (2n = 12) presents a bimodal karyotype with a large chromosome pair, which has a pericentric inversion in permanent heterozygosity with suppressed recombination, and five pairs of three to four times smaller chromosomes. Aiming to understand whether high copy number sequence composition differs between both chromosome sets, we investigated the repetitive DNA fraction of E. bulbosa and compared it to the chromosomal organization of the related Eleutherine latifolia species, not containing the pericentric inversion. We also compared the repetitive sequence proportions between the heteromorphic large chromosomes of E. bulbosa and between E. bulbosa and E. latifolia to understand the influence of the chromosome inversion on the dynamics of repetitive sequences. The most abundant repetitive families of the genome showed a similar chromosomal distribution in both homologs of the large pair and in both species, apparently not influenced by the species-specific inversions. The repeat families Ebusat1 and Ebusat4 are localized interstitially only on the large chromosome pair, while Ebusat2 is located in the centromeric region of all chromosomes. The four most abundant retrotransposon lineages are accumulated in the large chromosome pair. Replication timing and distribution of epigenetic and transcriptional marks differ between large and small chromosomes. The differential distribution of retroelements appears to be related to the bimodal condition and is not influenced by the nonrecombining chromosome inversions in these species. Thus, the large and small chromosome subgenomes of the bimodal Eleutherine karyotype are differentially organized and probably evolved by repetitive sequences accumulation on the large chromosome set.

Auditory and Somatosensory Interaction in Speech Perception in Children and Adults.

Multisensory integration (MSI) allows us to link sensory cues from multiple sources and plays a crucial role in speech development. However, it is not clear whether humans have an innate ability or whether repeated sensory input while the brain is maturing leads to efficient integration of sensory information in speech. We investigated the integration of auditory and somatosensory information in speech processing in a bimodal perceptual task in 15 young adults (age 19–30) and 14 children (age 5–6). The participants were asked to identify if the perceived target was the sound /e/ or /ø/. Half of the stimuli were presented under a unimodal condition with only auditory input. The other stimuli were presented under a bimodal condition with both auditory input and somatosensory input consisting of facial skin stretches provided by a robotic device, which mimics the articulation of the vowel /e/. The results indicate that the effect of somatosensory information on sound categorization was larger in adults than in children. This suggests that integration of auditory and somatosensory information evolves throughout the course of development.

The Effect of Hearing Aid Bandwidth and Configuration of Hearing Loss on Bimodal Speech Recognition in Cochlear Implant Users.

(1) To determine the effect of hearing aid (HA) bandwidth on bimodal speech perception in a group of unilateral cochlear implant (CI) patients with diverse degrees and configurations of hearing loss in the nonimplanted ear, (2) to determine whether there are demographic and audiometric characteristics that would help to determine the appropriate HA bandwidth for a bimodal patient. Participants were 33 experienced bimodal device users with postlingual hearing loss. Twenty three of them had better speech perception with the CI than the HA (CI>HA group) and 10 had better speech perception with the HA than the CI (HA>CI group). Word recognition in sentences (AzBio sentences at +10 dB signal to noise ratio presented at 0° azimuth) and in isolation [CNC (consonant-nucleus-consonant) words] was measured in unimodal conditions [CI alone or HAWB, which indicates HA alone in the wideband (WB) condition] and in bimodal conditions (BMWB, BM2k, BM1k, and BM500) as the bandwidth of an actual HA was reduced from WB to 2 kHz, 1 kHz, and 500 Hz. Linear mixed-effect modeling was used to quantify the relationship between speech recognition and listening condition and to assess how audiometric or demographic covariates might influence this relationship in each group. For the CI>HA group, AzBio scores were significantly higher (on average) in all bimodal conditions than in the best unimodal condition (CI alone) and were highest at the BMWB condition. For CNC scores, on the other hand, there was no significant improvement over the CI-alone condition in any of the bimodal conditions. The opposite pattern was observed in the HA>CI group. CNC word scores were significantly higher in the BM2k and BMWB conditions than in the best unimodal condition (HAWB), but none of the bimodal conditions were significantly better than the best unimodal condition for AzBio sentences (and some of the restricted bandwidth conditions were actually worse). Demographic covariates did not interact significantly with bimodal outcomes, but some of the audiometric variables did. For CI>HA participants with a flatter audiometric configuration and better mid-frequency hearing, bimodal AzBio scores were significantly higher than the CI-alone score with the WB setting (BMWB) but not with other bandwidths. In contrast, CI>HA participants with more steeply sloping hearing loss and poorer mid-frequency thresholds (≥82.5 dB) had significantly higher bimodal AzBio scores in all bimodal conditions, and the BMWB did not differ significantly from the restricted bandwidth conditions. HA>CI participants with mild low-frequency hearing loss showed the highest levels of bimodal improvement over the best unimodal condition on CNC words. They were also less affected by HA bandwidth reduction compared with HA>CI participants with poorer low-frequency thresholds. The pattern of bimodal performance as a function of the HA bandwidth was found to be consistent with the degree and configuration of hearing loss for both patients with CI>HA performance and for those with HA>CI performance. Our results support fitting the HA for all bimodal patients with the widest bandwidth consistent with effective audibility.

Electro-cortical correlates of multisensory integration using ecologically valid emotional stimuli: Differential effects for fear and disgust

Multisensory integration (MSI) is crucial for human communication and social interaction and has been investigated in healthy populations and neurodevelopmental disorders. However, the use of stimuli with high ecological validity is sparse, especially in event-related potential (ERP) studies. The present study examined the ERP correlates of MSI in healthy adults using short (500 ms) ecologically valid professional actor-produced emotions of fear or disgust as vocal exclamation or facial expression (unimodal conditions) or both (bimodal condition). Behaviourally, our results show a general visual dominance effect (similarly fast responses following bimodal and visual stimuli) and an MSI-related speedup of responses only for fear. Electrophysiologically, both P100 and N170 showed MSI-related amplitude increases only following fear, but not disgust stimuli. Our results show for the first time that the known differential neural processing of fear and disgust also holds for the integration of dynamic auditory and visual information.

Aural/Oral Performance of Children with Cochlear Implant under Monaural and Bimodal Listening Conditions: A Parental Evaluation

The study assessed the performance of children with cochlear implant (CI) under monaural and bimodal listening conditions using Parental Evaluation of Aural/Oral Performance of Children (PEACH) questionnaire. A total of 74 children using CI and their parents (either of the biological parent) served as subjects in the present study. The subjects were further divided into two groups based on mode of stimulation used in CI. Group I consisted of children using monaural stimulation in CI i.e. unilateral CI (monaural group). Group II consisted of children using bimodal stimulation in CI i.e. CI in one ear and hearing aid in opposite ear (bimodal group). The results revealed that the subjects of both groups performed significantly poorer under noisy listening conditions compared to quiet listening conditions. The subjects of both the groups performed similar under quiet listening environment. Although, both the groups performed similar under quiet listening condition, the subjects of bimodal group demonstrated significant improvement in aural/oral performance as compared to the subjects of monaural group under noisy listening environment. Thus, it can be inferred that bimodal stimulation in CI provides additional benefits as compared to monaural stimulation in CI especially under noisy listening environments. The findings of the present study complement the existing objective test results which have reported positive outcomes from bimodal stimulation in CI recipients.

Sentence Recognition in Quiet and Noise in School-Going Indian Children Using Bimodal Hearing.

To compare sentence recognition scores in quiet and noise in 8 to 15-years old children using bimodal hearing in CI only condition and bimodal condition (BM) (CI + HA). Twenty prelingually deafened participants (8-15years) using cochlear implant in one ear and hearing aid in the other ear were recruited. The sentence recognition was assessed in CI Quiet, CI + 15dB SNR, CI + 8dB SNR, BM Quiet, BM + 15dB SNR and BM + 8dB SNR. The highest sentence recognition scores were obtained in the quiet condition, followed by the + 15dB SNR and then by the + 8dB SNR condition in both CI only and BM conditions. The sentence recognition scores obtained in BM condition were significantly better than CI only condition. Variables like unaided PTA and aided PTA correlated significantly with the sentence recognition scores in BM conditions. This study was done on Indian population where till date no published data is available. It recommends that all the school going children using unilateral cochlear implants should be recommended to use a hearing aid in the contra lateral ear. This practice will help them to receive all the binaural benefits, better listening in noise, localization, spatial release from masking and pitch perception in comparison to unilateral CI use. Moreover, it will help to keep the auditory nerve viable for future implantation which is an important implication for children who have limited benefit from the contra lateral hearing aid.

Multimodal sensory information is represented by a combinatorial code in a sensorimotor system.

A ubiquitous feature of the nervous system is the processing of simultaneously arriving sensory inputs from different modalities. Yet, because of the difficulties of monitoring large populations of neurons with the single resolution required to determine their sensory responses, the cellular mechanisms of how populations of neurons encode different sensory modalities often remain enigmatic. We studied multimodal information encoding in a small sensorimotor system of the crustacean stomatogastric nervous system that drives rhythmic motor activity for the processing of food. This system is experimentally advantageous, as it produces a fictive behavioral output in vitro, and distinct sensory modalities can be selectively activated. It has the additional advantage that all sensory information is routed through a hub ganglion, the commissural ganglion, a structure with fewer than 220 neurons. Using optical imaging of a population of commissural neurons to track each individual neuron's response across sensory modalities, we provide evidence that multimodal information is encoded via a combinatorial code of recruited neurons. By selectively stimulating chemosensory and mechanosensory inputs that are functionally important for processing of food, we find that these two modalities were processed in a distributed network comprising the majority of commissural neurons imaged. In a total of 12 commissural ganglia, we show that 98% of all imaged neurons were involved in sensory processing, with the two modalities being processed by a highly overlapping set of neurons. Of these, 80% were multimodal, 18% were unimodal, and only 2% of the neurons did not respond to either modality. Differences between modalities were represented by the identities of the neurons participating in each sensory condition and by differences in response sign (excitation versus inhibition), with 46% changing their responses in the other modality. Consistent with the hypothesis that the commissural network encodes different sensory conditions in the combination of activated neurons, a new combination of excitation and inhibition was found when both pathways were activated simultaneously. The responses to this bimodal condition were distinct from either unimodal condition, and for 30% of the neurons, they were not predictive from the individual unimodal responses. Thus, in a sensorimotor network, different sensory modalities are encoded using a combinatorial code of neurons that are activated or inhibited. This provides motor networks with the ability to differentially respond to categorically different sensory conditions and may serve as a model to understand higher-level processing of multimodal information.

Distributional Information Shapes Infants’ Categorization of Objects

While distributional learning has been successfully demonstrated for auditory categorization, this study tests whether this mechanism also applies to object categorization: Ten‐month‐olds (n = 38) were familiarized with either a unimodal or bimodal distribution of a visual continuum. Using automatic eye tracking, we assessed categorization through the alternating/nonalternating paradigm. For infants in the bimodal condition, their average dwell time was larger for alternating trials than for nonalternating trials, while infants in the unimodal condition initially looked equally long at both types of trials. This group difference suggests that the shape of frequency distribution bears on the number of categories that infants construct from a continuum. Later in test, all infants show this alternating preference. We conclude that categorization is a flexible process, continuously adjusting itself to additional input.

Results in Adult Cochlear Implant Recipients With Varied Asymmetric Hearing: A Prospective Longitudinal Study of Speech Recognition, Localization, and Participant Report.

Asymmetric hearing with severe to profound hearing loss (SPHL) in one ear and better hearing in the other requires increased listening effort and is detrimental for understanding speech in noise and sound localization. Although a cochlear implant (CI) is the only treatment that can restore hearing to an ear with SPHL, current candidacy criteria often disallows this option for patients with asymmetric hearing. The present study aimed to evaluate longitudinal performance outcomes in a relatively large group of adults with asymmetric hearing who received a CI in the poor ear. Forty-seven adults with postlingual hearing loss participated. Test materials included objective and subjective measures meant to elucidate communication challenges encountered by those with asymmetric hearing. Test intervals included preimplant and 6 and 12 months postimplant. Preimplant testing was completed in participants' everyday listening condition: bilateral hearing aids (HAs) n = 9, better ear HA n = 29, and no HA n = 9; postimplant, each ear was tested separately and in the bimodal condition. Group mean longitudinal results in the bimodal condition postimplant compared with the preimplant everyday listening condition indicated significantly improved sentence scores at soft levels and in noise, improved localization, and higher ratings of communication function by 6 months postimplant. Group mean, 6-month postimplant results were significantly better in the bimodal condition compared with either ear alone. Audibility and speech recognition for the poor ear alone improved significantly with a CI compared with preimplant. Most participants had clinically meaningful benefit on most measures. Contributory factors reported for traditional CI candidates also impacted results for this population. In general, older participants had poorer bimodal speech recognition in noise and localization abilities than younger participants. Participants with early SPHL onset had better bimodal localization than those with later SPHL onset, and participants with longer SPHL duration had poorer CI alone speech understanding in noise but not in quiet. Better ear pure-tone average (PTA) correlated with all speech recognition measures in the bimodal condition. To understand the impact of better ear hearing on bimodal performance, participants were grouped by better ear PTA: group 1 PTA ≤40 dB HL (n = 19), group 2 PTA = 41 to 55 dB HL (n = 14), and group 3 PTA = 56 to 70 dB HL (n = 14). All groups showed bimodal benefit on speech recognition measures in quiet and in noise; however, only group 3 obtained benefit when noise was toward the CI ear. All groups showed improved localization and ratings of perceived communication. Receiving a CI for the poor ear was an effective treatment for this population. Improved audibility and speech recognition were evident by 6 months postimplant. Improvements in sound localization and self-reports of communication benefit were significant and not related to better ear hearing. Participants with more hearing in the better ear (group 1) showed less bimodal benefit but greater bimodal performance for speech recognition than groups 2 and 3. Test batteries for this population should include quality of life measures, sound localization, and adaptive speech recognition measures with spatially separated noise to capture the hearing loss deficits and treatment benefits reported by this patient population.

The respective contributions of visual and proprioceptive afferents to the mirror illusion in virtual reality.

The reflection of passive arm displacement in a mirror is a powerful means of inducing a kinaesthetic illusion in the static arm hidden behind the mirror. Our recent research findings suggest that this illusion is not solely visual in origin but results from the combination of visual and proprioceptive signals from the two arms. To determine the respective contributions of visual and proprioceptive signals to this illusion, we reproduced the mirror paradigm in virtual reality. As in the physical version of the mirror paradigm, one of the participant’s arms (the left arm, in our study) could be flexed or extended passively. This movement was combined with displacements of the avatar’s left and right forearms, as viewed in a first-person perspective through a virtual reality headset. In order to distinguish between visual and proprioceptive contributions, two unimodal conditions were applied separately: displacement of the avatar’s forearms in the absence of physical displacement of the left arm (the visual condition), and displacement of the left forearm while the avatar’s forearms were masked (the proprioceptive condition). Of the 34 female participants included in the study, 28 experienced a kinaesthetic mirror illusion in their static (right) arm. The strength of the illusion (expressed in terms of speed and duration) evoked by the bimodal condition was much higher than that observed in either of the two unimodal conditions. Our present results confirm that the involvement of visual signals in the mirror illusion—often considered as a prototypic visual illusion—has been overstated. The mirror illusion also involves non-visual signals (bilateral proprioceptive-somaesthetic signals, in fact) that interact with the visual signals and strengthen the kinaesthetic effect.

Multiple Approaches to Secure the Authenticity of the Film Music

영화를 구성하는 주된 요소는 영상과 음향(음악)이라는 점에 있어서는 이견이 없다. 그 가운데 영화에서 영상 즉, 시각적 측면이 주된 비중을 차지하고 있는 것으로 알려져 있다. 이는 시각(영상)적 효과가 청각(음악)적 효과에 비해 우월하다는 평가를 전제로 한다. 하지만 과연 그런가? 라는 의혹으로부터 출발하여 본 연구에서는 시각과 청각의 비교를 통하여 영화음악의 고유성을 확보하려는데 목적을 두고 있다. 우선, 시각과 청각의 여러 가지 요인을 조합하여 실험한 심리학의 연구 성과들에 대해 살펴보았다. 시각과 청각 두 가지 자극을 동시에 주는 이중 양상 조건에서 의미적 일치조건과 의미적 불일치조건으로 설정하고 실험을 진행하였을 때, 조건에 따라 시각 우세성 효과가 달라진다는 결과가 나타났다. 이는 결국 각기 다른 감각들의 조합에 따라 서로 다르게 인지되기도 하기 때문에, 시각이 청각에 비해 우세하지는 않다는 것을 의미하는 것이기도 하다. 또한 철학적 접근에 있어 칸트((I. Kant)와 흄(D. Hume)의 인식론에 비추어 인간이 감각-지각을 통해 외부세계를 어떻게 파악하는지에 대해 살펴보았다. 칸트에 따르면, 우리가 대상이나 사태를 인지하여 우리의 앎을 형성하기 위해서는 상상력의 도움을 받아 오성에 따른 판단이 이루어진 다음에 비로소 가능하다. 즉, 그 과정에서 모든 감각-지각(sense-perception)이 예외 없이 동원되어 감각-자료를 구성하게 되는 것이다. 또한 흄에 따르면, 우리는 외부세계에 대한 정보를 받아들여 인상을 형성하고 상상력에 의해 심상이라고 하는 관념을 형성함으로써 비로소 사유하게 되는 것이다. 즉, 인간이 사유한다는 것은, 곧 관념의 소유를 의미하는 것으로 기억과 함께 총체적으로 이루어지게 된다는 것이다. 정리하자면, 칸트와 흄의 논의에서 살펴보았듯이 우리는 시각적 정보와 청각적 정보를 동시에 받아들여 포괄적으로 인지하여 관념을 형성하게 된다는 점에서 특정한 지각의 우세성에 따라 인식이 이루어지지 않는다는 것을 알 수 있다. 이러한 연구들을 종합해 보았을 때, 영화음악이 갖는 고유성 확보 가능성에 있어 매우 긍정적인 결과라고 평가할 수 있을 뿐만 아니라, 영화에서 음악이 갖는 효과 내지 영향은 기존의 견해와는 다른 새로운 관점의 전환이 요구된다.There is no doubt that the image and sound are the main components of the film. It is common that the visual image takes major proportion of the film based on the premise that the assessment showing visual effect dominates auditory effect. In this study, I aimed to find the possibility to secure the authenticity of the film music by comparing visual and auditory senses to solve the suspicion over visual dominance effect. First of all, I examine previous psychological studies on combination using multiple factors of image and sound. The studies show the visual dominance effect differs when the experiment is performed with bimodal condition, which stimulates both visual and auditory senses, under either semantic congruency or semantic incongruency condition. Those results verify that visual sense does not always take a dominance over auditory senses because different combination of various sense makes the different sense-perception. Secondly, I study how human recognizes the external world via sense-perception based on the epistemology by I. Kant and D. Hume to approach psychologically. According to I. Kant, it is possible to form our knowledge through the recognition of the object and the state after the judgement of the understanding of imagination. All sense-perceptions consist sense-data during this judgement. Moreover, according to D. Hume, a human eventually owns the conception through construction of impression and formation of the idea called image by imagination, by the perception of the data of the external world. The meaning of owning human’s idea is equivalent to the possession of idea, and it is totally fulfilled with memory. As discussed through the ideas of I. Kant and D. Hume, I find the perception is not formed by the sense-specific dominance in regard to the formation of the idea through the comprehensive perception with visual and auditory data simultaneously. Regarding those studies, I evaluate that the possibility to secure the authenticity of the film music is very positive, and new point of view for either the effect of influence of film music is required to change from the conventional view.

Benefit and predictive factors for speech perception outcomes in pediatric bilateral cochlear implant recipients

IntroductionDespite recent advancement in the prediction of cochlear implant outcome, the benefit of bilateral procedures compared to bimodal stimulation and how we predict speech perception outcomes of sequential bilateral cochlear implant based on bimodal auditory performance in children remain unclear. ObjectivesThis investigation was performed: (1) to determine the benefit of sequential bilateral cochlear implant and (2) to identify the associated factors for the outcome of sequential bilateral cochlear implant. MethodsObservational and retrospective study. We retrospectively analyzed 29 patients with sequential cochlear implant following bimodal-fitting condition. Audiological evaluations were performed; the categories of auditory performance scores, speech perception with monosyllable and disyllables words, and the Korean version of Ling. Audiological evaluations were performed before sequential cochlear implant with the bimodal fitting condition (CI1+HA) and one year after the sequential cochlear implant with bilateral cochlear implant condition (CI1+CI2). The good performance group (GP) was defined as follows; 90% or higher in monosyllable and bisyllable tests with auditory-only condition or 20% or higher improvement of the scores with CI1+CI2. Age at first implantation, inter-implant interval, categories of auditory performance score, and various comorbidities were analyzed by logistic regression analysis. ResultsCompared to the CI1+HA, CI1+CI2 provided significant benefit in categories of auditory performance, speech perception, and Korean version of Ling results. Preoperative categories of auditory performance scores were the only associated factor for being GP (odds ratio=4.38, 95% confidence interval – 95%=1.07–17.93, p=0.04). ConclusionsThe children with limited language development in bimodal condition should be considered as the sequential bilateral cochlear implant and preoperative categories of auditory performance score could be used as the predictor in speech perception after sequential cochlear implant.