Neurophysiological evidence for underspecified lexical representations: asymmetries with word initial variations

Area of Science:

• Psycholinguistics
• Cognitive Neuroscience
• Phonetics

Background:

• The mental lexicon must accommodate phonetic variability in spoken word recognition.
• Understanding how the brain processes variations in consonant articulation is crucial for speech perception models.

Purpose of the Study:

• To investigate how the mental lexicon processes phonetic variants, specifically the place of articulation of initial consonants.
• To examine the asymmetry in activation between words and pseudowords differing in coronal versus noncoronal place of articulation.

Main Methods:

• Utilized a lexical decision task with and without fragment priming.
• Compared the processing of German words and pseudowords differing in initial consonant place of articulation.
• Analyzed event-related brain potentials (ERPs) to assess neural responses.

Main Results:

• Pseudowords with initial noncoronal place of articulation (e.g., *Brachen) significantly activated words with initial coronal place (e.g., Drachen).
• Conversely, coronal pseudowords (e.g., *Drenze) did not activate noncoronal words (e.g., Grenze) as effectively.
• An asymmetry was observed in the activation patterns, indicating differential processing based on phonetic features.

Conclusions:

• The speech recognition system can tolerate certain word onset variations, particularly when noncoronal variants activate coronal targets.
• This asymmetry suggests that coronal place of articulation may be underspecified in the mental lexicon.
• Findings contribute to understanding the representational and processing mechanisms underlying spoken word recognition.