Speech Recognition in Nonnative versus Native English-Speaking College Students in a Virtual Classroom

Area of Science:

• Audiology
• Speech-Language Pathology
• Educational Acoustics

Background:

• Classroom acoustics at the college level receive limited research attention.
• Nonnative English speakers are disproportionately affected by poor room acoustics compared to native speakers.
• Understanding the impact of classroom acoustics on nonnative college students' speech perception is crucial.

Purpose of the Study:

• To evaluate the combined effects of noise and reverberation on speech recognition in college students with varying English acquisition ages.
• To simulate classroom conditions with reverberation times (RTs) near ANSI recommendations.

Main Methods:

• A mixed-design study involving 36 native and nonnative English-speaking college students (ages 18-28) with normal hearing.
• Participants were divided into four groups: native monolingual, native bilingual, nonnative early, and nonnative late English speakers.
• Speech recognition in noise was assessed using the Bamford-Kowal-Bench Speech-in-Noise (BKB-SIN) test under three reverberant conditions (0.03, 0.06, and 0.08 seconds) and noise.

Main Results:

• Nonnative listeners required a significantly higher signal-to-noise ratio (SNR-50) for speech recognition compared to native listeners.
• Increased reverberation time (RT) led to a greater need for a favorable SNR-50 across all groups.
• Students with later English acquisition showed the most pronounced negative impact on speech recognition, while early bilinguals had a subtler effect.

Conclusions:

• Classroom acoustics are a critical factor for college students who are nonnative English speakers.
• Universities should adhere to ANSI recommendations for RT and reduce background noise to enhance speech clarity for all students.
• Implementing behavioral and instructional strategies is recommended to mitigate acoustic challenges beyond acoustic design.