Transfer effects from listening to frequency-controlled and frequency-shifted accelerated speech

Area of Science:

• Auditory perception
• Speech processing
• Human-computer interaction

Background:

• Speech intelligibility is crucial for effective communication.
• Altering speech signal parameters like frequency and rate can impact comprehension.
• Understanding how listeners adapt to modified speech is important for various applications.

Purpose of the Study:

• To investigate the effects of increased tonal frequency and speech rate on sentence intelligibility.
• To examine the role of listener practice with accelerated speech on subsequent comprehension.
• To determine if specific training with frequency-shifted (FS) or frequency-controlled (FC) accelerated speech enhances intelligibility.

Main Methods:

• Two experiments were conducted using recorded sentences.
• Experiment 1 manipulated speech frequency and rate independently and combined.
• Experiment 2 involved listener practice with FS and FC accelerated speech before an intelligibility test at double speed.

Main Results:

• Both increased frequency and increased speech rate independently impaired intelligibility.
• Listeners perceived accelerated sentences as spoken faster.
• Practice with accelerated speech improved intelligibility compared to no practice.
• Frequency-controlled (FC) acceleration resulted in higher intelligibility than frequency-shifted (FS) acceleration.
• Specific training (FS or FC) improved intelligibility for the matched test condition.

Conclusions:

• Increased speech frequency and rate significantly degrade sentence intelligibility.
• Listener adaptation to accelerated speech is possible through targeted practice.
• Frequency-controlled acceleration is more intelligible than frequency-shifted acceleration.
• Training specificity plays a key role in improving intelligibility of modified speech.