Examining the Intelligibility differences between two types of clear speech

This study investigates the intelligibility differences between global and focal clear speech adjustments in comparison to baseline or conversation speech. The objective is to determine what adjustments need to be made for individuals with speech disorders to produce intelligible and effective speech. Clear speech is a style of speaking where words are longer, articulatory precision is greater, and speaking rate is slower than conversational speech (Picheny et al. 1986). Clear speech represents a way of communication where the listener can understand what the talker says at a higher intelligibility rate. These adjustments have been proven to be beneficial for many individuals, specifically those with conditions like dysarthria secondary to amyotrophic lateral sclerosis (ALS) (Lee et al., 2019). This perceptual study recruited listeners through Prolific to listen to recordings of 9 different words embedded in speech-shaped noise produced by 12 talkers. Through conducting this study, we can understand what perceptual qualities contribute to higher intellgibility rates of clear speech while also considering factors such as vocal fatigue. This research study can help further speech recognition technologies, and speech therapy practices, and contribute to overall effective and efficient communication.