Technology Update SessionSession 1A Background: Speech-evoked auditory evoked potentials (AEPs)—including frequency-following responses (FFRs) and cortical auditory evoked potentials (CAEPs)—assess how the auditory system encodes meaningful, speech-like signals rather than the simple clicks or tones used in traditional AEPs. These responses can reveal timing, encoding, and neural-synchrony deficits that may be missed by standard ABR or audiometric testing. Speech-evoked AEPs are especially valuable when behavioral testing is unreliable, such as in young children or individuals with disabilities. However, conventional speech-evoked AEP recordings require many repetitions of a single speech token, a process that can be monotonous, insufficiently engaging for pediatric testing and does not test speech in a real environment. Method: A new continuous-speech recording option has been implemented in the SmartEP Duet system (Intelligent Hearing Systems Corp.). The Continuous Speech module acquires multiple AEP recordings from a single, uninterrupted speech file by playing a standard WAV file from the acquisition computer while simultaneously sending precise trigger signals through a secondary audio channel. Separate acquisition buffers aligned to each trigger allow up to four distinct responses to be recorded. A trigger-generation utility is provided to convert user generated mono WAV files into stereo files containing both the stimulus and embedded trigger markers. This approach enables the use of naturalistic materials—such as narrated stories with accompanying video—to sustain attention during testing. The system also permits comparison of responses to identical tokens occurring in different linguistic or acoustic contexts. The module also supports concurrent acquisition of early (brainstem) and cortical responses. Furthermore, the platform is open and compatible with a wide range of custom stimuli. Results: Examples of recordings obtained using both traditional speech-evoked AEP techniques and the Continuous Speech module will be presented. Objective response-detection methods for speech-based AEPs will also be compared. Conclusion: Speech-evoked AEPs offer crucial insight into how the auditory system processes meaningful speech. The ability to record and objectively analyze responses to continuous speech enhances validity, improves engagement during testing, and has the potential to advance diagnostic assessment of auditory processing. Keywords: Auditory Evoked Potentials (AEPs), Speech Evoked Potentials, Frequency Following Responses (FFR), Cortical Auditory Evoked Potentials (CAEPs), Continuous Speech Auditory Evoked Potential Testing
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