Contrastive adaptation in perception of speech versus song

Area of Science:

• Auditory Perception
• Psychoacoustics
• Speech and Music Cognition

Background:

• Previous research focused on stimulus characteristics defining speech vs. song boundaries.
• The influence of surrounding context on speech-song perception remained unclear.

Purpose of the Study:

• To investigate if contextual information can shift the perception of a vocalization as speech or song.
• To determine if this perceptual shift occurs across different timescales.

Main Methods:

• Experiment 1: Participants rated ambiguous speech-song stimuli preceded by unambiguous speech or song adaptors.
• Experiment 2: Re-analysis of existing data on speech-to-song transformation with repetition to examine contextual effects.

Main Results:

• Speech adaptors increased song-like ratings of ambiguous stimuli; song adaptors increased speech-like ratings.
• Following a speech-to-song transformation, subsequent stimuli were perceived as more speech-like.
• Contextual effects were observed across short (seconds) and medium (approx. 15s) timescales.

Conclusions:

• The perceptual boundary between speech and song is dynamic and context-dependent.
• Auditory perception integrates acoustic information with surrounding contextual cues.
• Contextual influences operate across multiple temporal scales in speech-song perception.