The influence of the bimodal stimulation on the auditory ability of temporal ordering

Rev. CEFAC. 2020;22(3):e15419 http://dx.doi.org/10.1590/1982-0216/202022315419 Original articles The influence of the bimodal stimulation on the auditory ability of temporal ordering Maria Madalena Canina Pinheiro1 https://orcid.org/0000-0003-1726-9703 Patrícia Ilsi Welter2 https://orcid.org/0000-0003-3536-8852 Jaqueline Cardoso Estácio2 https://orcid.org/0000-0003-3746-2551 1 Universidade Federal de Santa Catarina - UFSC, Centro de Ciências da Saúde, Departamento de Fonoaudiologia, Florianópolis, Santa Catarina, Brasil. 2 Universidade Federal de Santa Catarina - UFSC, Curso de Fonoaudiologia, Florianópolis, Santa Catarina, Brasil. Conflict of interests: Nonexistent ABSTRACT Objective: to analyze temporal ordering auditory ability in unilateral cochlear implant users with bimodal stimulation. Methods: the study included 15 unilateral cochlear implant users, six with bimodal stimulation and nine with exclusive cochlear implant and a control group consisting of 15 hearing individuals. Both groups underwent the standard duration and the standard frequency tests for temporal ordering auditory ability analysis. In the inferential analysis of the data, the nonparametric statistical tests Mann-Whitney and Kruskal-Wallis were used (p<0,05). Results: there was a significant difference in the performance of the standard frequency test, and subjects with bimodal stimulation presented a better performance than those with exclusive cochlear implants. The standard frequency test was associated with education and speech therapy. On the other hand, in the standard duration test, there was a relation with the implanted ear. The most frequent errors were discrimination for both temporal tests. Conclusion: bimodal stimulation, education and speech therapy influenced the performance of the frequency pattern test, while the implanted side influenced the performance of the duration pattern test. Keywords: Hearing; Hearing Loss; Cochlear Implant; Auditory Perception; Hearing Tests Received on: October 30, 2019 Accepted on: March 31, 2020 Corresponding Address: Maria Madalena Canina Pinheiro Centro de Ciências da Saúde – CCS, Curso de Fonoaudiologia, Campus Universitário - Trindade Rua Delfino Conte, s/ número CEP: 88040-900 – Florianópolis, Santa Catarina, Brasil E-mail: 1/10 2/10 | Pinheiro MMC, Welter PI, Estácio JC INTRODUCTION The sense of hearing is fundamental for the development of oral communication and, consequently, for human social interaction. The auditory system transmits environmental and speech sounds to the auditory cortex, where the information is processed to produce a perception of the signal1. Auditory alterations can seriously impact quality of life, affecting social, professional and psychological aspects of the individual. Currently, the electronic devices most used in hearing rehabilitation of individuals with hearing loss are the Individual Sound Amplification Device (ISAD) and the Cochlear Implant (CI)2,3. The use of hearing aids can benefit individuals with mild to profound hearing loss. However, as they are sound amplifiers, a sufficient cochlear reserve for good speech perception is required. Individuals who have a bilateral high-grade hearing impairment, and have no benefit from the use of hearing aids, are candidates for the use of CI4. The use of unilateral CI and of contralateral hearing aid to the implanted ear is called bimodal stimulation. This stimulation can be a good option to improve communication of individuals who have auditory residue in the non-implanted ear, bringing benefits such as improved sound localization, speech recognition in both silence and noise5,6. For the perception of speech sounds to occur properly, the integrity of the peripheral and central auditory pathway is important, as the presence of alterations can cause losses in the processing of the information received7. The CI promotes important changes in the auditory restoration and in the users’ well-being; however there is still a great variability in the performance of this population8. Central Auditory Processing (CAP) refers to the efficiency and effectiveness with which the Central Auditory Nervous System (CANS) uses the auditory information. However, factors such as cognitive aspects, experience and the individual’s motivation can influence the analysis of the acoustic signal9. The CAP presents a set of fundamental auditory skills for the processing of verbal and non-verbal information, including temporal aspects composed by the ability to integrate, discriminate, mask and temporal processing9. In Brazil, temporal ordering and resolution skills are the most evaluated aspects in clinical test batteries10. The auditory ability of temporal ordering refers to the ability to process multiple sound stimuli according to the order in which they appear over a period of time. Rev. CEFAC. 2020;22(3):e15419 | doi: 10.1590/1982-0216/202022315419 The temporal processing can be considered the basis for the development of most of the auditory processing skills; this is due to the influence of time on the characteristics that encompass hearing information11. CANS functions are in some way subject to the influence of time. Speech and language comprehension depend on the ability to work with sound sequences12. Currently in clinical practice, the Frequency Pattern Test (FPT) and the Duration Pattern Test (DPT) are the most used to assess the temporal ordering ability13. These tests involve the ability to order the frequency and duration of sounds and the recognition of acoustic aspects over time10. The relationships between signal processing by the central auditory system and the use of CI are still sources of several investigations that associate the benefits of using the device to individual auditory perception and of other non-auditory factors14,15. Investigations have already sought to review the temporal skills of resolution and temporal ordering in post-lingual CI users using DPT, FPT and the Gaps in Noise (GIN) test3,16. The limited production of research in this area impairs knowledge and the development of new technologies that can benefit this population. The aim of this study was to analyze the auditory ability of temporal ordering in users of unilateral cochlear implant and those with bimodal stimulation, in addition to the influence of socio-demographic variables, device usage time and speech therapy. METHODS The study was submitted to and approved by the Research Ethics Committee (REC) of the Federal University of Santa Catarina, SC, Brazil, under number 2,054,587 and CAAE number 65513617.4.0000.0121. This is a quantitative, descriptive, experimental, crosssectional investigation. Participants were properly guided and accepted to participate in the investigation on a voluntary basis after signing the Free and Informed Consent Form (FICF). The population was divided into two groups: Study Group (SG) and Control Group (CG). The SG was composed of 15 individuals (...truncated)