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Stroke in children and adolescents: Analysis of electrophysiological and behavioral assessment findings of auditory processing

Abstract

Purpose:

This study aimed to analyze the auditory processing behavior of children and adolescents diagnosed with stroke and compare it with that of typically developing individuals.

Methods:

This was an analytical cross-sectional study involving 48 participants aged between 7 and 17 years with adequate schooling for age and grade, allocated equally to two groups: Stroke (SG) and Control Groups (CG). For the SG, cases identified between 2003 and 2018 were considered. In the CG, school-aged participants with typical development were randomized. After screening for differential audiological assessment and confirmation of auditory pathway integrity at the brainstem level, binaural analyses of the auditory processing behavior were conducted using the Dichotic Digit Test (DDT), Frequency Pattern Test (FPT), and electrophysiological assessment (P300). The Shapiro-Wilk test for normality was conducted, followed by the T and Mann-Whitney tests, with a 95 % confidence level and significance offset at p < 0.05, using the SPSS software (IBM®, v. 22.)

Results:

The CG performed better in terms of auditory processing. These differences were significant (p < 0.0001) for the binaural integration of DDT, FPT humming and Labeling, and P300 latency. The P300 results were similar; however, with a greater amplitude in the SG.

Conclusion:

This study showed that children and adolescents with stroke performed worse in electrophysiological and behavioral tests of auditory processing assessed using the auditory evoked potentials. These data reinforce the hypothesis that stroke-related lesions compromise the neural mechanisms underlying auditory processing.

Keywords:
Children; Adolescents; Stroke; Hearing; Auditory evoked potentials; Auditory processing disorders

HIGHLIGHTS

Auditory processing behavior of children diagnosed with stroke was analyzed.

Children and adolescents with stroke performed worse in auditory processing tests.

Stroke-related lesions compromise the auditory neural mechanisms.

Introduction

Cerebral Vascular Accidents (CVA) in children and adolescents are rarely described. However, they are becoming increasingly important, and are emerging conditions in the field of research because of complications and require high diagnostic accuracy, as the signs and symptoms manifested initially may have little specificity, with clinical presentations being similar to those of other neurological diseases or those related to the central nervous system.11 Mekitarian Filho E, Carvalho WB. Stroke in Clindren. J Pediatr 2009;85(6):469–79., 22 Numis AL, Fox CK. Arterial ischemic stroke in children: risk factors and etiologies. Curr Neurol Neurosci Rep 2014;14(1):422.

Most available studies on pediatric stroke have small sample sizes, making the diagnostic approach, treatment, and determination of prevalence rates difficult.33 Gumer LB, Del Vecchio M, Aronoff S. Strokes in children: a systematic review. Pediatr Emerg Care 2014;30(9):660–4. In this context, the literature review has made important advances in identifying the etiology of the disease. The most common causes are vascular malformations, followed by Moyamoya Syndrome, arterial dissection, heart disease and cardioembolic phenomena, sickle cell anemia, adverse effects of other treatments, brain tumors, and trauma;33 Gumer LB, Del Vecchio M, Aronoff S. Strokes in children: a systematic review. Pediatr Emerg Care 2014;30(9):660–4., 44 Hollist M, Au K, Morgan L, Shetty PA, Rane R, Hollist A, Amaniampong A, Kirmani BF. Pediatric stroke: overview and recent updates. Aging Dis 2021;12(4):1043–55., 55 Rawanduzy CA, Earl E, Mayer G, Lucke-Wold B. Pediatric stroke: a review of common etiologies and management strategies. Biomedicines 2022;11(1):2. and more than 27 % of cases may have an unknown etiology.33 Gumer LB, Del Vecchio M, Aronoff S. Strokes in children: a systematic review. Pediatr Emerg Care 2014;30(9):660–4.

Stroke can occur due to sudden occlusion, causing ischemia or infarction in the encephalic territory, and is characterized as an acute ischemic stroke. It can also present in a hemorrhagic form when the cerebral veins or arteries rupture, and both forms can result in focal lesions and neurological clinical deficits.66 Bernard TJ, Goldenberg NA. Pediatric arterial ischemic stroke. Pediatr Clin North Am 2008;55:323–38. The international incidence rates range from 1.2 to 13 per 100,000 children.55 Rawanduzy CA, Earl E, Mayer G, Lucke-Wold B. Pediatric stroke: a review of common etiologies and management strategies. Biomedicines 2022;11(1):2., 66 Bernard TJ, Goldenberg NA. Pediatric arterial ischemic stroke. Pediatr Clin North Am 2008;55:323–38., 77 Fullerton HJ, Wu YW, Zhao S, Johnston SC. Risk of stroke in children: ethnic and gender disparities. Neurology 2003;61(2):189–94., 88 Lynch JK. Cerebrovascular disorders in children. Curr Neurol Neurosci Rep 2004;4(2):129–38., 99 Tsze DS, Valente JH. Pediatric stroke: a review. Emerg Med Int 2011;2011:734506., 1010 Mirabelli-Badenier M, Braunersreuther V, Lenglet S, Galan K, Veneselli E, Viviani GL, Mach F, Montecucco F. Pathophysiological role of inflammatory molecules in paediatric ischaemic brain injury. Eur J Clin Invest 2012;42(7):784–94.

Due to the challenges involved in early diagnosis, it is possible that the incidence of pediatric stroke is underestimated. In contrast to hemorrhagic stroke in adults, which is present in 7.5–19 % of cases, hemorrhagic events in children are present in 35–54 % of cases.55 Rawanduzy CA, Earl E, Mayer G, Lucke-Wold B. Pediatric stroke: a review of common etiologies and management strategies. Biomedicines 2022;11(1):2. The disease in this population has a devastating effect on the quality of life and has a significant socioeconomic impact. Deaths occur in up to 10 % of cases with recurrence in 20 %, and 75 % of children remain with neurological problems such as seizures, sensory and motor deficits, behavioral disorders, and intellectual disability, which hinder learning and language.1111 Felling RJ, Sun LR, Maxwell EC, Goldenberg N, Bernard T. Pediatric arterial ischemic stroke: Epidemiology, risk factors, and management. Blood Cells Mol Dis 2017;67:23–33.

Another aggravating aspect is that childhood strokes can affect all levels of the auditory pathway, leading to deficits in reception and/or auditory perception. These can manifest as a variety of symptoms and clinical presentations that begin acutely before, during, or shortly after the stroke.1212 Bamiou DE. Hearing disorders in stroke. Handb Clin Neurol 2015;129:633–47. For this population, the integrity of the auditory pathway and the typical development of the neural mechanisms underlying auditory processing are fundamental for the acquisition and development of language and learning processes.1313 Northern JL, Downs MP. Childhood hearing. Rio de Janeiro: Guanabara Koogan; 2005. p. 10–376.

According to the American Speech-Language-Hearing Association (2005) and the American Academy of Audiology (2010), postnatal events such as trauma or neurological infection can result in an acquired auditory processing disorder.1414 American Speech-Landuage-Hearing Association. Auditory processing disorders. 1–20., 1515 Musiek FE, Baran JA, Bellis TJ, Chermak GD, Hall III JW, RW Keith, et al. American Academy of Audiology Clinical Practice guidelines: diagnosis, treatment and management of children and adults with central auditory processing disorder. 20101–51. Neurodevelopmental and auditory processing disorders after stroke have not been frequently studied and are still poorly documented, despite the relevance of this topic.1616 Rees P, Callan C, Chadda K, Vaal M, Diviney J, Sabti S, et al. School-age outcomes of children after perinatal brain injury: a systematic review and meta-analysis. BMJ Paediatr Open 2023;7(1):e001810. A systematic review published in 2023 investigated the interventions applied to perception disorders in children after stroke. Randomized clinical trials reported touch disorders, mixed tactile-somatosensory and somato-sensory disorders, and changes in visual perception. However, studies that addressed hearing, which depends on the specific mental functions of recognition and interpretation remain lacking in the literature.1717 Hazelton C, Thomson K, Todhunter-Brown A, Campbell P, Chung CS, Dorris L, et al. Interventions for perceptual disorders following stroke. Cochrane Database Syst Rev 2022;11(11):CD007039.

Considering the rarity of this clinical condition and the importance of investigating auditory skills, the aim of this study was to analyze the findings of electrophysiological assessments and auditory processing behavior of children and adolescents diagnosed with stroke and compare them with healthy individuals with typical development.

Material and methods

Design

This analytical cross-sectional study was approved by the Research Ethics Committee under protocol nº 77900517.2.0000.5334 and was conducted in accordance with the Declaration of Helsinki and STROBE guidelines. This study was conducted at the Center for Auditory Electrophysiology of the Federal University of Rio Grande do Sul (UFRGS) and the Department of Physiotherapy, Speech Therapy, and Occupational Therapy of the University of São Paulo (USP) School of Medicine, São Paulo (SP). Free and informed consent was obtained from all participants and their respective parents.

Sample

The study analyzed children and adolescents who were included after their parents provided informed consent. The samples were then divided into two groups.

Stroke Group (SG): Children and adolescents diagnosed with stroke were treated and followed up at a neuropediatric reference unit in Porto Alegre, Rio Grande do Sul, Brazil.

Control Group (CG): Healthy children and adolescents with typical development were recruited from public schools in the same city.

To make up the SG, the cases identified during the period were considered, while for the CG, individuals were randomized from a sample of 500 school-age children and adolescents with typical development for data comparison purposes.

Inclusion and exclusion criteria

The following were considered for both the study groups: age between 7 and 17 years, 11 months, and 30 days; minimum follow-up time of 1 year after stroke; appropriate school performance for age and school year; no previous auditory complaint; adequate auditory capacity with a type A tympanometric curve; and integrity of the auditory pathways at the level of the brainstem, as confirmed by screening and neuro-pediatric evaluation of the participants.

Patients with SG were diagnosed with ischemic or hemorrhagic stroke between 2003 and 2018. In the CG, school-aged children and adolescents selected and assessed between 2016 and 2018 were included.

Individuals in both groups with neurological sequelae that precluded audiological assessment were excluded.

Screening

All participants underwent screening and binaural assessment by an audiologist using the following institutional protocol:

  1. Anamnesis and overall data collection as well as medical history and ontological data.

  2. Meatoscopy to determine the presence of cerumen or foreign bodies.

  3. Immittance testing with an Interacoustics® AT235h Impedance Audiometer, in order to identify the tympanometric curve and analyze ipsilateral and contralateral acoustic reflexes at frequencies of 500, 1000, 2000, and 4000 Hz.

  4. Pure-tone audiometry, which followed the American National Standards Institute (ANSI-69) guidelines, assessed the auditory thresholds at frequencies between 250 and 8000 Hz.1818 Jerger J. Clinical experience with impedance audiometry. Arch Otolaryngol 1970;92(4):311–24.

  5. Vocal audiometry was used to determine the Speech Percentage Recognition Index (SPRI) and Speech Recognition Threshold (SRT), followed by the presentation of twenty-five monosyllabic words at 40 dB HL, the intensity of which gradually declined until the participant understood and repeated 50 % of the words.

  6. Behavioral and electrophysiological assessments were performed using the Auditory Brainstem Response (ABR), which consists of emitting specific auditory evoked potentials at 80 dB HL with alternate polarity, to confirm the auditory pathway integrity at the brainstem level.1919 Hall J. Handbook of auditory evoked responses. Boston: Allyn & Bacon; 1992. p. 1–871.

The screening data were used to select the study participants whose data were not used to demonstrate the results.

Behavioral analysis of auditory processing

The study analyzed the participants’ central auditory processing using the Dichotic Digit Test (DDT), Frequency Pattern Test (FPT), and electrophysiological assessment (P300).

The DDT is a behavioral test of central auditory processing that assesses the perception and understanding of speech sounds related to the acquisition and understanding of language. In addition to the auditory system, the test challenges cognitive functions as it requires attention and memory for execution.2020 Fischer ME, Cruickshanks KJ, Nondahl DM, Klein BEK, Klein R, Pankow JS, et al. Dichotic digits test performance across the ages: results from two large epidemiologic cohort studies. Ear Hear 2017;38(3):314–20., 2121 Bresola JO, Padilha FYOMM, Braga Junior J, Pinheiro MMC. The use of the dichotic digit test as a screening method. Codas 2021;33(6):e20200314. This evaluation method is useful for screening auditory processing disorders and stands out for its low complexity and practicality of application, thus enabling its use for screening in a school environment. It is also recommended for the evaluation of individuals with neurological sequelae, with a sensitivity and specificity of 90 % and 83 %, respectively.2121 Bresola JO, Padilha FYOMM, Braga Junior J, Pinheiro MMC. The use of the dichotic digit test as a screening method. Codas 2021;33(6):e20200314.

The procedures described in the auditory processing evaluation manual were adopted for this application.2222 Pereira LD, Schochat E. Behavioral auditory tests to assess central auditory processing (Testes auditivos comportamentais para avaliacão do processamento auditivo central). Pró-Fono Sci Update J 2011:1–82. A recording was turned on the acoustic booth, with an intensity of 50 Db HL in relation to the SRT, which repeated a list with 25 sequences of digits presented in a dichotic and random manner (e.g., three, five, six, and eight), totaling 100 digits in each ear. The number of correct answers was converted into a percentage to be analyzed later. The test evaluates the binaural integration based on the participant’s ability to repeat the presented numbers orally. The binaural separation was determined by the ability to repeat the numbers presented orally to each ear.

The FPT is used to assess the auditory electrophysiological potential involved in central auditory processing and is characterized by its ability to determine the location and lateralization as well as the recognition and discrimination of sound characteristics in environments with competitive noise.

This test was also conducted in an acoustic booth, using 40 sequences of sounds recorded at 50 dB HL above the tritonal average, at frequencies between 500 and 2000 Hz. Three different acoustic signals were presented in each sequence, of which two sounds were emitted at the same frequency and the third at different frequencies. Each tone was parameterized with duration, interval, and rise and fall times of 200, 150, and 10 ms, respectively. The evaluation took place in two stages, the first instructing the participant to imitate the sound (humming) and the second to characterize the sounds in categories “high-pitched or shrill” or “coarse or deep” (labeling). The answers were converted into a percentage of correct answers, considering ≥75 % as the standard of normality.2323 Musiek FE. Frequency (pitch) and duration pattern tests. J Am Acad Audiol 1994;5(4):265–8.

For the P300, four electrodes were placed: one on the forehead, one on the scalp, and two on the mastoid processes. The impedance was regulated until reaching intensities ≥ 5 Ω, and a difference ≥ 2 Ω between electrodes was accepted. Subsequently, an Electroencephalography (EEG) was performed to record spontaneous brain activity and identify artifacts, followed by an ABR test.

After this preliminary stage, P300 was applied using a Contronic® Masbe ATC Plus device, and the participants were instructed to speak or wave their hands whenever they perceived a different sound signal. The binaural test exhibited a sequence of frequent stimuli (tone burst at 1000 Hz), and different and less frequent stimuli presented randomly (tone burst at 2000 Hz). The following criteria were used: 200 µV full scale; 20 ms plateau and rise and fall times of 5 ms; 0.5 Hz high-pass filter; 20 Hz low-pass filter, Notch – SIM; 1000 ms reading window; presentation of 300 stimuli, 20 % of which were rare. The P300 wave latency was marked at the point of maximum amplitude, and all electrophysiological recordings were analyzed by two experienced examiners. The latency data were recorded in milliseconds (ms) and amplitudes in microvolts (µV).2424 Didone DD, Garcia MV, Oppitz SJ, Da silva TFF, Dos Santos SN, Bruno RS, et al. Auditory evoked potential P300 in adults: reference values. Einstein 2016;14(2):208–12.

In addition to the data obtained from the auditory processing assessment, the following data were collected: stroke classification, age at stroke onset, age at assessment, sex distribution, and the brain region affected.

Statistical analysis

The Shapiro-Wilk test was conducted to determine the data normality in each auditory processing assessment, followed by non-parametric tests to ascertain the differences between the study groups.

The t-test was applied to compare the normally distributed data with those obtained using the Mann-Whitney U test for analyses that used non-normally distributed data. A 95 % Confidence Interval was established at a significance level of p < 0.05. The tests were performed using the Statistical Package for the Social Sciences (SPSS) software version 22.

Results

Thirty-five children/adolescents diagnosed with stroke between 2003 and 2018 were identified, 25 of whom agreed to participate in the study and 24 of whom met the inclusion criteria (SG). In addition, 24 individuals with typical development (CG) were included. Therefore, this study included 48 participants.

The entire sample suffered a stroke between 2 and 10 years of age, and it was found that in 91.67 % of the cases, the stroke occurred in early childhood (before four years of age). All participants were evaluated in the chronic phase after stroke, with the shortest follow-up time recorded at the time of the assessments being 1 year and the longest being 12 years after stroke. Most patients were girls, and the stroke was ischemic in the left cerebral hemisphere. The epidemiological profiles of the study participants are presented in Table 1.

Table 1
Descriptive analysis of the epidemiological profile of participants in the experimental and control groups regarding age, sex, brain region, and type of stroke.

Significant differences in auditory processing were observed between children diagnosed with stroke and those with normal development.

With respect to DDT, the means and standard deviations for the “integration” variable analyzed in the right ear was SG: 76.83 ± 16.35 and CG: 99.90 ± 0.50, and for the left ear were SG: 82.67 ± 15.48 and CG: 99.00 ± 1.25. A comparative intergroup analysis revealed a statistically significant difference in integration capacity (p < 0.0001).

For the “separation” variable, the results for the right ear were SG: 78.83 ± 14.36 and CG: 97.70±2.69, and for the left were SG: 90.33 ± 10.43 and CG: 97.10 ± 2.47. Regarding separation, there was a significant difference in the right ear (p < 0.0001); however, the findings in the left ear were statistically similar (p = 0.0716). The medians, quartiles, and outliers for each variable are presented in Fig. 1.

Fig. 1
Percentage of correct answers for the integration (A) and separation (B) variables identified by DDT for the SG and CG. (*) Significant statistical difference, p < 0.0001; (**) Statistically similar data.

The students with typical development performed better on the FPT, obtaining a higher percentage of correct answers when compared to the children and adolescents diagnosed with stroke, in both “labeling” and “humming”. The average “humming” percentages and standard deviations for the SG and CG groups were 78.83 ± 9.36 and 93.20 ± 6.49, respectively. For “labeling,” the percentage of correct answers was 46.00 ± 15.38 for the experimental group and 83.73 ± 9.30 for controls. The differences between the modalities were statistically significant (p < 0.0001). The medians, quartiles, and outliers for each variable and study group are shown in Fig. 2.

Fig. 2
Percentage of correct answers for PPS Humming and Labeling modalities for the SG and CG.* Significantly different (p < 0.0001).

Children and adolescents with typical development also performed better in the electrophysiological assessment of the P300 test, and the differences were significant for latency and similar for binaural response amplitude.

The mean and standard deviations of the latency, expressed in milliseconds (ms) in the right ear, for the SG and CG, were 495.96 ± 112.91 and 306.43 ± 11.90, respectively; (p < 0.0001), and 502.84 ± 113.18 and 306.96 ± 18.34, respectively for the left ear (p < 0.0001).

For the amplitudes, expressed in microvolts (µV), the following means were obtained in the right ear for the SG and CG: 16.07 ± 6.18 and 13.15 ± 4.78 respectively; (p = 0.0777), and 16.63 ± 6.83 and 13.22 ± 4.95, respectively for the left ear; (p = 0.0566). The medians, quartiles, and outliers for latency and amplitude in both groups are shown in Fig. 3.

Fig. 3
Latency (A) and amplitude (B) measured during P300 in groups SG and CG. (*) Significant statistical difference, p < 0.0001.

Discussion

Stroke has a significant functional impact on an individual’s quality of life.2525 Strater R, Becker S, von Eckardstein A, Heinecke A, Gutsche S, Junker R, et al. Prospective assessment of risk factors for recurrent stroke during childhood–a 5-year follow-up study. Lancet 2002;360(9345):1540–5. However, few studies have investigated the impact of stroke on central auditory pathways in the brain. The authors believe that this scarcity is because other morbidities resulting from stroke could ‘mask’ the difficulties in auditory processing skills. Patients typically report hearing difficulties only when asked about or evaluated using specific tests.1212 Bamiou DE. Hearing disorders in stroke. Handb Clin Neurol 2015;129:633–47., 2626 Bamiou DE, Werring D, Cox K, Stevens J, Musiek FE, Brown MM, Luxon LM. Patient-reported auditory functions after stroke of the central auditory pathway. Stroke 2012;43(5):1285–9., 2727 Koohi N, Vickers D, Chandrashekar H, Tsang B, Werring D, Bamiou DE. Auditory rehabilitation after stroke: treatment of auditory processing disorders in stroke patients with personal frequency-modulated (FM) systems. Disabil Rehabil 2017;39(6):586–93.

The present study described the function of the auditory pathway in children and adolescents with stroke and proposed new therapeutic perspectives that can help recover communicative functions in this population.

The present data demonstrated a close connection between the structural damage caused by stroke and impaired auditory pathway functionality (auditory perception skills), both through behavioral and electrophysiological tests.

The SG comprised 24 individuals: 13 girls (54 %) and 11 boys (46 %). Some studies have reported a higher prevalence in males77 Fullerton HJ, Wu YW, Zhao S, Johnston SC. Risk of stroke in children: ethnic and gender disparities. Neurology 2003;61(2):189–94., 2525 Strater R, Becker S, von Eckardstein A, Heinecke A, Gutsche S, Junker R, et al. Prospective assessment of risk factors for recurrent stroke during childhood–a 5-year follow-up study. Lancet 2002;360(9345):1540–5., 2828 Avila L, Riesgo R, Pedroso F, Goldani M, Danesi M, Ranzan J, et al. Language and focal brain lesion in childhood. J Child Neurol 2010;25(7):829–33., 2929 Elias KMIF, Moura-Ribeiro MVL. Stroke caused auditory attention deficits in children. Arquivos de Neuropsiquiatr 2013;71(1):11–7., 3030 Elias KMIF, Oliveira CA, Airoldi MJ, Franco KMD, Rodrigues SD, Ciasca SM, et al. Central auditory processing outcome after stroke in children. Arq Neuropsiquiatr 2014;72(9):680–6., 3131 Morgan CT, Manlhiot C, McCrindle BW, Dipchand AI. Outcome, incidence, and risk factors for stroke after pediatric heart transplantation: an analysis of the International Society for Heart and Lung Transplantation Registry. J Heart Lung Transplant 2016;35(5):597–602. than in females.3232 Montenegro MA, Guerreiro MM, Scotoni AE, Tresoldi AT, Moura-Ribeiro MV. Doenca cerebrovascular na infância. I. Manifestacões epilepticas [Cerebrovascular disease in children: I. Epileptic manifestations]. Arq Neuropsiquiatr 1999;57(3A):587–93., 3333 Rotta NT, da Silva AR, da Silva FLF, Ohlweiler L, Belarmino Jr E, Fonteneles VR, et al. Cerebrovascular disease in pediatric patients. Arq Neuropsiquiatr 2002;60(4):959–63., 3434 Matta APC, Galvao KRF, Oliveira BS. Cerebrovascular disorders in childhood: etiology, clinical presentation, and neuroimaging findings in a case series study. Arq Neuropsiquiatr 2006;64(2a):181–5., 3535 Ghotra SK, Johnson JA, Qiu W, Newton A, Rasmussen C, Yager JY. Age at stroke onset influences the clinical outcome and health-related quality of life in pediatric ischemic stroke survivors. Dev Med Child Neurol 2015;57(11):1027–34., 3636 Gerzson LR, Ranzan J, de Almeida KS, Riesgo RS. The impact of stroke on the quality of life of children and adolescents (O impacto do acidente vascular cerebral na qualidade de vida de criancas e adolescents). Fisioterapia Pesquisa 2018;25(3):241–50.

Regarding the type of stroke, most of the sample consisted of ischemic stroke (92 %). This prevalence has been corroborated by several studies on stroke in both adult and pediatric populations.3030 Elias KMIF, Oliveira CA, Airoldi MJ, Franco KMD, Rodrigues SD, Ciasca SM, et al. Central auditory processing outcome after stroke in children. Arq Neuropsiquiatr 2014;72(9):680–6., 3434 Matta APC, Galvao KRF, Oliveira BS. Cerebrovascular disorders in childhood: etiology, clinical presentation, and neuroimaging findings in a case series study. Arq Neuropsiquiatr 2006;64(2a):181–5., 3636 Gerzson LR, Ranzan J, de Almeida KS, Riesgo RS. The impact of stroke on the quality of life of children and adolescents (O impacto do acidente vascular cerebral na qualidade de vida de criancas e adolescents). Fisioterapia Pesquisa 2018;25(3):241–50. This is because most of the published studies were conducted in follow-up and rehabilitation centers, and in cases of hemorrhagic stroke in children, the number of deaths was higher.2525 Strater R, Becker S, von Eckardstein A, Heinecke A, Gutsche S, Junker R, et al. Prospective assessment of risk factors for recurrent stroke during childhood–a 5-year follow-up study. Lancet 2002;360(9345):1540–5., 3434 Matta APC, Galvao KRF, Oliveira BS. Cerebrovascular disorders in childhood: etiology, clinical presentation, and neuroimaging findings in a case series study. Arq Neuropsiquiatr 2006;64(2a):181–5., 3737 Mathias E, Sethuraman U. Ischemic stroke of the spinal cord: a pediatric emergency in an otherwise healthy child. J Emerg Med 2016;51(1):73–6.

The injury locations in the study population showed a wide diversity in neuroimaging findings. However, most patients had an injury to the temporal left hemisphere (63 %). This is due to the location of the Middle Cerebral Artery (MCA), the most commonly affected vascular region, which is more prone to injury due to its anatomy and thinner walls.3434 Matta APC, Galvao KRF, Oliveira BS. Cerebrovascular disorders in childhood: etiology, clinical presentation, and neuroimaging findings in a case series study. Arq Neuropsiquiatr 2006;64(2a):181–5., 3636 Gerzson LR, Ranzan J, de Almeida KS, Riesgo RS. The impact of stroke on the quality of life of children and adolescents (O impacto do acidente vascular cerebral na qualidade de vida de criancas e adolescents). Fisioterapia Pesquisa 2018;25(3):241–50., 3838 Mah S, deVeber G, Wei XC, Liapounova N, Kirton A. Cerebellar atrophy in childhood arterial ischemic stroke: acute diffusion MRI biomarkers. Stroke 2013;44(9):2468–74.

The results of the behavioral tests, DDT, and PPS, showed that the SG performed worse than the CG in all the tasks.

In the DDT, the SG performed worse in the tasks of integration and binaural separation in both ears than the CG. These findings corroborate those of other studies that examined the same population.2929 Elias KMIF, Moura-Ribeiro MVL. Stroke caused auditory attention deficits in children. Arquivos de Neuropsiquiatr 2013;71(1):11–7., 3939 Elias KMIF, Santos MFC, Ciasca SM, Moura-Ribeiro MVL. Auditory processing in a child with cerebrovascular disease (Processamento auditivo em crianca com doenca cerebrovascular). Pró-Fono Scientific Update J 2007;19(4):393–400.

In the dichotic listening task, different verbal stimuli were presented concurrently to each ear. To evaluate the binaural integration, the authors measured the neural capacity to integrate each stimulus presented simultaneously to both ears. With respect to binaural separation, the authors evaluated the neural capacity to direct attention to each ear. That is, information from one ear must be ignored and attention must be directed to the other. Neural injuries/dysfunctions resulting from strokes in the SG compromise these auditory skills, and consequently, healthy auditory processing of acoustic information in the brain.

Another important issue in the dichotic listening task is that when an individual is asked to respond to different verbal stimuli presented simultaneously to each ear, the stimuli are processed predominantly by the contralateral auditory pathway owing to the suppression of its ipsilateral counterpart.2828 Avila L, Riesgo R, Pedroso F, Goldani M, Danesi M, Ranzan J, et al. Language and focal brain lesion in childhood. J Child Neurol 2010;25(7):829–33., 2929 Elias KMIF, Moura-Ribeiro MVL. Stroke caused auditory attention deficits in children. Arquivos de Neuropsiquiatr 2013;71(1):11–7.

As the hemispheric specialization of language occurs in the left hemisphere, in most cases, the right ear usually performs better, a phenomenon known as right ear advantage.1515 Musiek FE, Baran JA, Bellis TJ, Chermak GD, Hall III JW, RW Keith, et al. American Academy of Audiology Clinical Practice guidelines: diagnosis, treatment and management of children and adults with central auditory processing disorder. 20101–51. In this study, when analyzing only individuals with injuries in the right or left hemisphere, the authors found that, as expected, the majority performed worse in the ear contralateral to the lesion owing to the nature of the test.4040 Bamiou DE, Musiek FE, Stow I, Stevens J, Cipolotti L, Brown MM, et al. Auditory temporal processing deficits in patients with insular stroke. Neurology 2006;67(4):614–9. In addition, the authors found abnormal ipsilateral results, similar to those obtained in other studies.3030 Elias KMIF, Oliveira CA, Airoldi MJ, Franco KMD, Rodrigues SD, Ciasca SM, et al. Central auditory processing outcome after stroke in children. Arq Neuropsiquiatr 2014;72(9):680–6., 4141 Isaacs E, Christie D, Vargha-Khadem F, Mishkin M. Effects of hemispheric side of injury, age at injury, and presence of seizure disorder on functional ear and hand asymmetries inhemiplegic children. Neuropsychologia 1996;34(2):127–37. These different results could be due to the extent of the injuries, and hemispheric reorganization may have occurred.3030 Elias KMIF, Oliveira CA, Airoldi MJ, Franco KMD, Rodrigues SD, Ciasca SM, et al. Central auditory processing outcome after stroke in children. Arq Neuropsiquiatr 2014;72(9):680–6., 4141 Isaacs E, Christie D, Vargha-Khadem F, Mishkin M. Effects of hemispheric side of injury, age at injury, and presence of seizure disorder on functional ear and hand asymmetries inhemiplegic children. Neuropsychologia 1996;34(2):127–37., 4242 Hugdahl K. What can be learned about brain function from dichotic listening? Rev Esp Neuropsicol 2000;2(3):62–84.

SG performed worse in the PPS test in both the labeling and humming modes. This result showed that the SG was inefficient at perceiving, associating, and interpreting the non-verbal patterns of the message received, such as rhythm and intonation, which are most often processed by the right hemisphere, affecting comprehension with regard to phoneme voicing and syllable order.4343 Musiek FE, Baran JA, Pinheiro ML. Duration pattern recognition in normal subjects and patients with cerebral and cochlear lesions. Audiology 1990;29(6):304–13., 4444 Musiek FE, Baran AS, Pinheiro ML. Behavioral and electrophysiological test procedures. Neuroaudiology: case studies. San Diego: Singular Publishing Group; 1994. p. 7–28., 4545 Bamiou DE, Spraggs PR, Gibberd FB, Sidey MC, Luxon LM. Hearing loss in adult Refsum’s disease. Clin Otolaryngol Allied Sci 2003;28(3):227–30., 4646 Bamiou DE, Free SL, Sisodiya SM, Chong WK, Musiek F, Williamson KA, et al. Auditory interhemispheric transfer deficits, hearing difficulties, and brain magnetic resonance imaging abnormalities in children with congenital aniridia due to PAX6 mutations. Arch Pediatr Adolesc Med 2007;161(5):463–9.

The present results corroborate those of previous studies, demonstrating that individuals with brain injury perform worse on the PPS than normal individuals, regardless of the affected hemisphere or injury location.3030 Elias KMIF, Oliveira CA, Airoldi MJ, Franco KMD, Rodrigues SD, Ciasca SM, et al. Central auditory processing outcome after stroke in children. Arq Neuropsiquiatr 2014;72(9):680–6., 4747 Delecrode CR, Cardoso ACV, Frizzo ACF, Guida HL. Tonal frequency and duration pattern tests in Brazil: literature review (Testes tonais de padrão de frequência e duração no Brasil: revisão de literature). Rev CEFAC 2014;16(1):283–93. These findings demonstrate that the PPS is a highly sensitive test for brain damage since the required skills involve several brain areas from both the hemispheres, such as the primary auditory cortex, auditory association areas, and language-related regions (temporoparietal) when a verbal response is needed.4848 Musiek FE, Pinheiro ML. Frequency patterns in cochlear, brainstem, and cerebral lesions. Audiology 1987;26(2):79–88.

The activation of these different regions of the brain is associated with several neural processes required to perform this test. Recognizing an acoustic pattern and intonation, presumably, has been predominantly associated with the right hemisphere (humming mode). When the task requires labeling, in addition to the right hemisphere, the corpus callosum and language-related regions in the left hemisphere are activated.4747 Delecrode CR, Cardoso ACV, Frizzo ACF, Guida HL. Tonal frequency and duration pattern tests in Brazil: literature review (Testes tonais de padrão de frequência e duração no Brasil: revisão de literature). Rev CEFAC 2014;16(1):283–93., 4848 Musiek FE, Pinheiro ML. Frequency patterns in cochlear, brainstem, and cerebral lesions. Audiology 1987;26(2):79–88.

Electrophysiological tests contribute to behavioral assessments of auditory processing because they objectively check the functional and structural integrity of the auditory pathway in the brain.2323 Musiek FE. Frequency (pitch) and duration pattern tests. J Am Acad Audiol 1994;5(4):265–8., 4949 Mcpherson DL, Ballachanda B, Kaf W. Middle and long latency auditory evoked potentials. Audiology diagnosis. New York: Thieme; 2007. p. 443–77.

In this study, the P300 was used because this potential is associated with cognitive skills related to the auditory system and reflects activity in the auditory cortex in terms of attention, discrimination, integration, and memory.4848 Musiek FE, Pinheiro ML. Frequency patterns in cochlear, brainstem, and cerebral lesions. Audiology 1987;26(2):79–88., 4949 Mcpherson DL, Ballachanda B, Kaf W. Middle and long latency auditory evoked potentials. Audiology diagnosis. New York: Thieme; 2007. p. 443–77.

The results obtained in the SG showed an increased latency compared to those in the CG. Thus, the authors can infer that the central auditory nervous system takes longer to process auditory information in children and adolescents with brain injuries. The damage caused by the injury itself likely impairs the normal functioning of neural pathways, causing auditory and cognitive function disorders. Some studies on brain disorders have demonstrated that this neural slowness is a result of injury.5050 Fjell AM, Rosquist H, Walhovd KB. Instability in the latency of P3a/P3b brain potentials and cognitive function in aging. Neurobiol Aging 2009;30(12):2065–79., 5151 Kihara M, de Haan M, Were EO, Garrashi HH, Neville BG, Newton CR. Cognitive deficits following exposure to pneumococcal meningitis: an event-related potential study. BMC Infect Dis 2012;12:79. This type of disorder has also been described in studies on children with language development disorders,5252 Shaheen EA, Shohdy SS, Abd Al Raouf M, Mohamed El Abd S, et al. Relation between language, audio-vocal psycholinguistic abilities and P300 in children having specific language impairment. Int J Pediatr Otorhinolaryngol 2011;75(9):1117–22. learning disorders,5353 Souza J, Rocha VO, Berticelli AZ, Didone DD, Sleifer P. Auditory Latency Response – P3 in children with and without learning complaints. Audiol Commun Res 2017;22:e1690.stuttering,5454 Jerônimo GM, Scherer APR, Sleifer P. Long-latency auditory evoked potential in children with stuttering. Einstein São Paulo 2020;18:1–6. and aging.5555 Hsu LC, Lo SF, Lin CY, Chen FF, Lo YC, Chou LW, et al. Impact of putamen stroke on task context updating: Evidence from P300 brain waves. J Clin Neurosci 2018;55:45–51.

The P300 amplitude has been widely questioned in the literature owing to its high variability5656 Romero ACL, Capellias AS, Frizzo ACF. Cognitive potential of children with attention deficit and hyperactivity disorder. Braz J Otorhinolaryngol 2013;79(5):609–15., 5757 Kozlowska K, Melkonian D, Spooner CJ, Scher S, Meares R. Cortical arousal in children and adolescents with functional neurological symptoms during the auditory oddball task. Neuroimage Clin 2016;13:228–36. and attentional influence. However, it is noteworthy that SG had higher amplitude values than CG.

Vaughan and Kurtzberg studied children and adolescents with functional neurological disorders and found increased amplitudes in this population compared to their healthy peers. The authors hypothesized that these participants would exhibit cortical excitation. The baseline state of high excitation could be a pre-condition for generating functional neurological symptoms in these individuals, justifying their higher potential amplitude when compared to controls, which is a plausible hypothesis because stroke may cause interhemispheric imbalance.5858 Vaughan HG, Kurtzberg D. Electrophysiologic indices of human brain maturation and cognitive development. In: Gunnar MR, Nelson CA, eds. Developmental behavioral neuroscience, Lawrence Erlbaum Associates; 1992:1–36. Another hypothesis that the authors proposed was the possible compensation for attentional levels in the SG when performing the discrimination task required in the P300 potential.

In this study, the small sample size represented one of the limitations and reinforced the series of diseases presented in the literature, since the authors identified only 35 children or adolescents diagnosed with stroke over a period of 15 years (2003 to 2018), of which 24 were eligible for the analyses. Another limiting factor for this investigation was the scarcity of audiometric studies involving children with stroke-related neurological sequelae caused by stroke. Therefore, the authors emphasize the importance of future studies that address these issues in greater detail.

Conclusion

This study showed that children and adolescents with stroke performed worse in electrophysiological and behavioral tests of auditory processing assessed using auditory evoked potentials. These data reinforce the hypothesis that stroke-related lesions compromise the neural mechanisms underlying auditory processing.

Acknowledgments

This work was conducted with the support of the Higher Education Personnel Improvement Coordination, Brazil (Capes), Finance Code 001.

  • Data availability statement
    The authors declare that all data are available to reviewers of the journal.
  • Funding
    CAPES/USP.

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Publication Dates

  • Publication in this collection
    13 Nov 2023
  • Date of issue
    2023

History

  • Received
    09 Mar 2023
  • Reviewed
    25 Aug 2023
  • Accepted
    06 Sept 2023
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