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

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.

To investigate the effect of phonological disorders on Frequency-Following Responses (FFRs) in the time domain.

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.

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).

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.