*3.2.3.1 Tone burst*

The literature reports alterations in the components of the LLAEP in children with language disorders and also in those with phonological disorders [36] changes that are frequently associated with problems arising from OM. Researchers note that OM can lead to changes in central auditory pathways [30, 37, 38]. However, there are few studies that have associated the LLAEP responses in children with a history of OM **Figure 6**.

Maruthy and Mannarukrishnaiah [31], Shaffer [30], Sanfins [33], and Colella-Santos [11] reported similar results, i.e., the presence of LLAEP changes in children with a history of OME. In the studies by Maruthy and Mannarukrishnaiah [32], all components of the LLAEP (P1, N1, P2, and N2) were significantly longer in

**73**

history of OME.

*LLAEP. Personal collection.*

*3.2.3.2 Speech*

**Figure 6.**

**Figure 5.**

[30, 39, 40].

*Otitis Media, Behavioral and Electrophysiological Tests, and Auditory Rehabilitation*

children with an SOM history. Shaffer [31] showed an increase in the latencies of N1 and P2, associated with the absence of the P300, in the majority of children evaluated. Sanfins [34] found prolongation of latencies only for P2 and N2 (for females), in comparison with the responses of children without otological alterations. Colella-Santos [11] observed an increase in P2, N2, and P300 latencies in children with a

*Comparison (left vs. right ear) of absolute latency values of FFR components in children with a history of otitis media (right panel) and children with no history of otitis media (left panel), from Sanfins et al. [32].*

The LLAEP with verbal stimuli provides additional information about the biological processes involved in speech processing, enabling the collection of information complementary to those obtained by standard behavioral evaluations

*DOI: http://dx.doi.org/10.5772/intechopen.88800*

**Figure 4.** *FFR. Personal collection.*

*Otitis Media, Behavioral and Electrophysiological Tests, and Auditory Rehabilitation DOI: http://dx.doi.org/10.5772/intechopen.88800*

#### **Figure 5.**

*The Human Auditory System - Basic Features and Updates on Audiological Diagnosis and Therapy*

the CANS and, over time, activities that depend on binaural auditory processing (binaural interaction and binaural integration, among others) can be compromised

Few studies have investigated the frequency following response (FFR) in cases of otitis media. A study of two groups of children with a history of bilateral OM (recent onset and long-term) showed that FFR responses were affected in a statistically significant way in the onset portions (waves V and A) and offset portion (wave O), along with reduced values of the VA complex (more specifically VA slope) when responses between the groups were compared. The findings suggest that long-term OM in children is associated with a reduced neural conduction velocity relative to the processing time of speech stimuli, either at the beginning (onset) or final portion (offset), resulting in a decrease in the coding of speech in the brainstem [35]

Sanfins et al. [32] reported that children with a history of SOM present an increase in the absolute latency of all FFR waves compared to children with no history of otological problems. In addition, children without hearing loss have more coherent responses in both ears, whereas the group of children with a history of OME has a greater dispersion of latencies in all FFR components (**Figure 5**). Colella-Santos et al. [11] also reported a decrease in VA slope in girls with OME.

The literature reports alterations in the components of the LLAEP in children with language disorders and also in those with phonological disorders [36] changes that are frequently associated with problems arising from OM. Researchers note that OM can lead to changes in central auditory pathways [30, 37, 38]. However, there are few studies that have associated the LLAEP responses in children with a

Maruthy and Mannarukrishnaiah [31], Shaffer [30], Sanfins [33], and Colella-Santos [11] reported similar results, i.e., the presence of LLAEP changes in children with a history of OME. In the studies by Maruthy and Mannarukrishnaiah [32], all components of the LLAEP (P1, N1, P2, and N2) were significantly longer in

due to the auditory imbalance arising from OM.

*3.2.3 Long latency auditory evoked potential*

*3.2.2 Frequency following response*

**Figure 4**.

*3.2.3.1 Tone burst*

history of OM **Figure 6**.

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**Figure 4.**

*FFR. Personal collection.*

*Comparison (left vs. right ear) of absolute latency values of FFR components in children with a history of otitis media (right panel) and children with no history of otitis media (left panel), from Sanfins et al. [32].*

**Figure 6.** *LLAEP. Personal collection.*

children with an SOM history. Shaffer [31] showed an increase in the latencies of N1 and P2, associated with the absence of the P300, in the majority of children evaluated. Sanfins [34] found prolongation of latencies only for P2 and N2 (for females), in comparison with the responses of children without otological alterations. Colella-Santos [11] observed an increase in P2, N2, and P300 latencies in children with a history of OME.

#### *3.2.3.2 Speech*

The LLAEP with verbal stimuli provides additional information about the biological processes involved in speech processing, enabling the collection of information complementary to those obtained by standard behavioral evaluations [30, 39, 40].

In the studies of Sanfins [33], children with bilateral OME presented prolonged latencies for N1, P2, N2 (female), and P300, in comparison with responses of children without auditory changes. Children with unilateral OME had prolonged latencies for P2 and P300 in comparison to the responses from healthy children.

The evaluation of the LLAEP using both nonverbal and verbal stimuli seems to be able to identify neurophysiological changes resulting from OM. However, it is important to note that, in unilateral OM episodes, only verbal sound stimuli (speech LLAEP) seem to be able to differentiate groups on the basis of latency. OM impairs speech perception as a result of a failure to recognize sound signals (discrimination, storage, memory). Therefore, the more accurate identification of LLAEP changes with verbal and non-verbal stimuli may relate to underlying OM.
