The Implicit Learning of Speech-Print Associations in Structured Language Streams

• In Event: Learning How the Brain Acquires Statistical Regularities: Implications for Education

Abstract

Objectives: Learning to associate spoken and written language is essential for reading acquisition. Characterizing the neurocognitive processes through which such correspondence is gradually established may deepen our understanding of (a)typical reading development.

Theoretical framework: According to the Predictive Coding Framework, our brain can generate predictions based on probabilistic models (top-down), and update such models and predictions based on the (mis)match with sensory input (bottom-up). In natural language, basic spoken and written representations are embedded in larger units (e.g., words and sentences) containing various phonological and lexical regularities, which may facilitate predictive coding and aid the learning of speech-print associations.

Methods: Here we employed electroencephalography (EEG) with a frequency-tagging approach to investigate how the implicit structure of parallel speech input influences written language tracking and the acquisition of speech-print correspondences.

Materials: We exposed 30 typically reading adults to audiovisual stimuli composed of (1) auditory sequences of random syllables (i.e., unstructured condition) or tri-syllabic words (i.e., structured condition) and (2) corresponding visual letters (i.e., familiar condition) or contrast- and size-matched artificial symbols (i.e., implicit learning condition). Participants were not informed of the systematic correspondence between artificial symbols and syllable sounds in the implicit learning conditions.

Results: After three blocks of audiovisual exposure (~6 min) to 12 novel speech-print combinations, participants were found to successfully identify the artificial symbols that match the syllable sounds they heard in both unstructured (hit rate = .75 ± .16) and structured (.73 ± .14) conditions. This behavioral learning effect was further confirmed by increased cortical tracking of artificial symbols compared to that of familiar letters in a posterior scalp region, and this effect gradually increased over time. Although the presence of word structure did not
significantly enhance this associative learning at the group level, individual learners who exploited the structure information and allocated their attention to both words and syllables tended to have better memory for the artificial symbols.

Significance: Together, our study uncovers a gradual establishment of speech-print association in posterior brain sites. Moreover, coordinated tracking across single linguistic units and their higher-order structures is suggested to be a challenging yet scaffolding process that may facilitate associative learning. This may not only benefit future research on the dynamic trajectory of reading acquisition and its underlying neurocognitive mechanisms, but also inspire the development of educational programs that unblock the barriers to learning and embrace the complexity of neurodevelopment.

Authors

• Manli Zhang, University of Hong Kong
  Presenting Author

• Lars Riecke, Maastricht University
  Non-Presenting Author

• Milene Bonte, Maastricht University
  Non-Presenting Author