Working Memory Capacity Modulates the Dual Pathways of Semantic Interference and Facilitation in Speech Production

Area of Science:

• Cognitive Psychology
• Psycholinguistics
• Neuroscience

Background:

• Semantic effects in speech production are typically studied using the picture-word interference (PWI) paradigm.
• Object-level variables like semantic relationships influence these effects, but subject-level cognitive factors, especially working memory capacity (WMC), are less understood.

Purpose of the Study:

• To investigate how working memory capacity (WMC) modulates semantic interference and facilitation effects in speech production.
• To examine the differential impact of WMC on categorical versus associative semantic relationships during lexical access.

Main Methods:

• Participants were categorized into high (n=29) and low (n=29) working memory capacity (WMC) groups based on screening.
• Two picture-word interference (PWI) tasks assessing categorical and associative semantic relations were administered.
• Naming latencies were measured to quantify semantic effects.

Main Results:

• A significant semantic interference effect was observed for categorical relations, which was stronger in the low-WMC group than the high-WMC group.
• A notable semantic facilitation effect occurred for associative relations, being more pronounced in the high-WMC group compared to the low-WMC group.
• Working memory capacity (WMC) dynamically adjusted the magnitude of semantic effects, attenuating interference and enhancing facilitation.

Conclusions:

• Working memory capacity (WMC) is a critical moderator in speech production, influencing lexical access dynamics.
• Individual differences in WMC significantly shape how semantic information is processed during word retrieval.
• This research bridges a gap by integrating cognitive factors into models of speech production architecture.