Overnight changes to dual-memory processes reflected in speech-perceptual performance.

Area of Science:

• Cognitive Science
• Neuroscience
• Linguistics

Background:

• Individual differences exist in learning and retaining nonnative speech sounds.
• The role of acoustic-phonetic memory consolidation in speech perception is not fully understood.

Purpose of the Study:

• To investigate how memory systems and perceptual skills contribute to nonnative speech contrast perception over two days.
• To explore the relationship between different memory types (implicit, explicit) and speech sound learning and retention.

Main Methods:

• Twenty-one adults (18-24 years) completed implicit and explicit learning tasks, including nonnative (Hindi) speech-sound training.
• Performance was assessed shortly after learning and 12 hours later, followed by a native speech-sound categorical perception task on a separate day.

Main Results:

• Nonnative speech perception correlated with implicit learning initially and explicit memory after an overnight delay.
• Native speech-sound perception showed a stronger association with nonnative speech perception on the second day.

Conclusions:

• Speech sounds may be encoded by parallel memory systems, with perceptual performance reflecting knowledge from different systems over time.
• Both native and nonnative speech perception might utilize similar retrieval mechanisms for long-term storage.