What Does a Cue Do? Comparing Phonological and Semantic Cues for Picture Naming in Aphasia

Purpose

Impaired naming is one of the most common symptoms in aphasia, often treated with cued picture naming paradigms. It has been argued that semantic cues facilitate the reliable categorization of the picture, and phonological cues facilitate the retrieval of target phonology. To test these hypotheses, we compared the effectiveness of phonological and semantic cues in picture naming for a group of individuals with aphasia. To establish the locus of effective cueing, we also tested whether cue type interacted with lexical and image properties of the targets.

Method

Individuals with aphasia (n = 10) were tested with a within-subject design. They named a large set of items (n = 175) 4 times. Each presentation of the items was accompanied by a different cueing condition (phonological, semantic, nonassociated word and tone). Item level variables for the targets (i.e., phoneme length, frequency, imageability, name agreement, and visual complexity) were used to test the interaction of cue type and item variables. Naming accuracy data were analyzed using generalized linear mixed effects models.

Results

Phonological cues were more effective than semantic cues, improving accuracy across individuals. However, phonological cues did not interact with phonological or lexical aspects of the picture names (e.g., phoneme length, frequency). Instead, they interacted with properties of the picture itself (i.e., visual complexity), such that phonological cues improved naming accuracy for items with low visual complexity.

Conclusions

The findings challenge the theoretical assumptions that phonological cues map to phonological processes. Instead, phonological information benefits the earliest stages of picture recognition, aiding the initial categorization of the target. The data help to explain why patterns of cueing are not consistent in aphasia; that is, it is not the case that phonological impairments always benefit from phonological cues and semantic impairments form semantic cues. A substantial amount of the literature in naming therapy focuses on picture naming paradigms. Therefore, the results are also critically important for rehabilitation, allowing for therapy development to be more rooted in the true mechanisms through which cues are processed.

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