The role of language and sensorimotor information in memory for concepts

The linguistic-simulation approach to conceptual representations has been investigated for some time, but the role of language and sensorimotor information in memory for objects and words, both short- and long-term, has not been examined in detail. In the present thesis, I look at the interplay of sensorimotor and linguistic information in conceptual knowledge and examine which aspects of concepts are represented in memory tasks. I also aim to establish the role of consciously accessing conceptual information in word recognition and memory. The thesis includes three self-contained papers which show that the conceptual system relies on linguistic or sensorimotor information according to task demands. In the paper in Chapter 4, I examined the linguistic bootstrapping hypothesis, which postulates that linguistic labels can serve as placeholders for complex sensorimotor representations. I tested the capacity of working memory for object concepts using an articulatory suppression task to block access to language. I found that working memory capacity for contextually related object concepts when relying on sensorimotor information is higher than the traditionally reported capacity of 3-4 for simple shapes or colours. Additionally, when linguistic labels are available to deputise for complex sensorimotor information, the capacity further increases by up to two object concepts. In Chapters 5 and 6, I examined the content of conceptual information stored in long-term memory, and the role of sensorimotor simulation and consciously available information in word recognition and word memory. The studies revealed that consciously generated imagery is not reliably measured, and moreover, it does not contribute to word recognition in a consistent manner. Some of the effects of imageability found in the literature can be explained or subsumed by sensorimotor information, which is not fully available through conscious awareness. However, conscious imagery may be a useful strategy to support word memory when trying to explicitly remember words. The thesis demonstrates that both linguistic labels and sensorimotor information contribute to memory for concepts. The way a concept is represented in different tasks varies depending on task demands. Linguistic information is used to circumvent resource capacity limits, while sensorimotor information guides behaviour by providing more detailed information about the meaning of concepts, and our previous experience with them