Analysis of the components of Frequency-Following Response in phonological disorders

Introduction: When identifying the auditory performance of children with phonological disorders, researchers assume that this population has normal peripheral hearing. However, responses at more central levels might be atypical. Objective: To investigate the effect of phonological disorders on Frequency-Following Responses (FFRs) in the time domain. Methods: Participants were 60 subjects, aged 5 to 8:11 years, divided into two groups: a control group, composed of 30 subjects with normal language skills; and a study group composed of 30 subjects diagnosed with Phonological Disorder (PD). All subjects were tested for Frequency-Following Responses. Results: In the group of children with PD there was an increase in the latency of all FFR components, with a significant statistical difference for components V (p = 0.015); A (< 0.001); C (0.022); F (< 0.001); and O (0.001). There was also a reduction in the Slope measure in the group with PD (p = 0.004). Conclusion: The FFR responses are altered in children with PD. This suggests that children with PD present a disorganization in the neural coding of complex sounds. This could compromise specially the development of linguistic/phonological abilities, which can reflect in daily communication.