We outline a proposal to relate modelling of word meaning in terms of semantic features and frames to a general hierarchical model of neurocognitive processing [1]. The model assumes that concrete features are processed in low-level, posterior sensory networks, whereas abstract conceptualization involves integration of frame-based information, making it more dependent on higher cognitive functions orchestrated by frontal networks. Episodic memory networks are suggested to be at an intermediate level, i.e. more concrete than general semantic frames, but less concrete than sensory-based information. A word association test was used to investigate the processing of concrete and abstract nouns. Speakers with stroke-related aphasia due to anterior and posterior lesions and healthy controls participated. Assuming visual memory networks to be important for concrete noun processing, left occipital lesions were hypothesized to impair the interpretation of concrete words. Lesions affecting left anterior areas were expected to give rise to the reverse pattern due to difficulties in accessing general semantic frames. Results supported the hypotheses. Compared with controls, anterior aphasic subjects produced fewer semantic frame-based associations, but more associations based on episodic memories and sensory feature similarity. In contrast, occipital lesions implicated fewer associations based on sensory features but more on semantic frames.

References

1. Fuster. Journal of Cognitive Neuroscience 2009, 21, 2047-2072