Strength of German accent under altered auditory feedback

Area of Science:

• Speech-language pathology
• Psychoacoustics
• Second language acquisition

Background:

• Borden's hypothesis posits that individuals with vulnerable speech systems depend more on feedback monitoring.
• Second language (L2) speech is considered more vulnerable than native language (L1) speech.
• Altered auditory feedback (AAF) is hypothesized to detrimentally affect L2 speech production.

Purpose of the Study:

• To investigate the effect of altered auditory feedback (AAF) on accent strength in second language (L2) speakers.
• To test Borden's hypothesis regarding feedback monitoring in vulnerable speech systems.
• To determine if specific types of AAF exacerbate L2 accentuation.

Main Methods:

• Six German speakers recorded English (L2) speech under six auditory feedback conditions: normal, amplified, frequency-shifted, delayed, slowed, and accelerated.
• Judges were trained to reliably differentiate German-accented English from native English.
• Recordings were ranked by accent strength under each condition to assess the impact of AAF.

Main Results:

• Accent strength was significantly more pronounced under frequency-shifted and delayed auditory feedback conditions compared to normal or amplified feedback.
• Control tests confirmed that judges were rating accent, not fluency changes induced by AAF.
• The findings indicate a differential impact of AAF types on L2 accentuation.

Conclusions:

• The results support Borden's hypothesis by demonstrating that AAF disrupts speech control in L2 speakers, leading to increased accent.
• Frequency-shifted and delayed auditory feedback appear to be particularly disruptive to L2 accentuation.
• The study highlights the crucial role of auditory feedback in maintaining stable L2 speech production and accent consistency.