Concreteness effects in different tasks: implications for models of short-term memory.

Area of Science:

• Cognitive Psychology
• Psycholinguistics
• Neuroscience

Background:

• Concreteness effects, where concrete words are recalled better than abstract words, are well-documented in memory research.
• The underlying mechanisms, particularly the role of phonological and lexical-semantic representations, remain debated.
• Previous hypotheses suggested these effects arise during speech production, a notion this study addresses.

Purpose of the Study:

• To investigate the role of phonological and lexical-semantic representations in concreteness effects within short-term memory.
• To examine how different short-term memory tasks (serial recall, matching span, order reconstruction, free recall) and articulatory suppression influence concreteness effects.
• To test the redintegration hypothesis by examining effects in tasks with and without spoken output requirements.

Main Methods:

• Participants performed various short-term memory tasks (serial recall, matching span, order reconstruction, free recall) under control and articulatory suppression conditions.
• Concreteness effects were measured by comparing recall performance for concrete versus abstract words.
• Task demands were manipulated to stress either item or order information retention.

Main Results:

• No dissociation of concreteness effects was found between tasks requiring spoken output and those that do not, challenging the redintegration hypothesis.
• Concreteness effects were modulated by task demands, being stronger for item-focused tasks (free recall) than order-focused tasks (serial recall).
• Articulatory suppression (weakening phonological representations) enhanced concreteness effects for item recall, while effects reversed under specific conditions of weak phonological and overactivated lexical-semantic representations.

Conclusions:

• Phonological representations are critical for retaining order information in short-term memory.
• Lexical-semantic representations are essential for maintaining item identity, functioning in both input and output buffers.
• These findings support a dual-representation model of short-term memory, integrating item and order information processing.