Exploring the interaction between phonological and semantic distractor effects on speech production

Alissa Melinger and Rasha Abdel Rahman
Max Planck Institute for Psycholinguistics, The Netherlands

In the classic picture-word interference paradigm, categorically related distractors produce interfering effects on picture naming latencies while phonologically related distractors produce facilitative effects. Additionally, some studies have found that associatively related distractors also facilitate picture naming. While these effects are well-attested, the respective loci in the speech production system are unclear. In this study, we examine whether the different types of distractors affect common or different levels of processing. In order to investigate the interactions between different distractor types, we
developed a modified version of the picture-word interference paradigm in which we present multiple distractor words to allow for various combinations.

By pairing each picture with two distractors, we evaluate the combined effects of presenting a categorical relative with a
phonological relative (e.g. MOUSE - HORSE, MOUNTAIN; Experiment 1), a categorical relative with an associative relative (e.g., MOUSE - HORSE, CHEESE; Experiment 2), or an associative relative with a phonological relative (e.g., MOUSE - CHEESE, MOUNTAIN; Experiment 3). We compare these heterogeneous pairs to homogeneous pairs such as two categorical relatives (e.g., MOUSE - HORSE, TIGER), two phonological relatives (e.g., MOUSE - MOUNTAIN, MOUTH), etc.

Under the assumption of discreteness, two types of distractors exhibiting an additive result pattern affect different levels of
processing; two types of distractors exhibiting an interactive result pattern affect the same level of processing.

The result pattern for the homogeneous distractor pairs successfully replicates the classic effects of interference for category members and facilitation for phonological and associative relatives, showing that processing two distractors is not significantly different in nature from processing one distractor. Interestingly, we find no interaction between category and phonological information while we do find an interaction between category and associative relations. (Data on the
relationship between associative and phonological relatives are still being collected.) Using distractor pairs in a picture-word interference paradigm, we present reaction time data suggesting that category and associative distractors operate at the same processing level in the speech production system while phonological distractors operate at a separate processing level. It is generally assumed that category structure is imposed on conceptual/semantic knowledge. Our result suggests that conceptual/semantic knowledge is also organized into associative networks. Thus, category and associative relationships reflect two dimensions of organization within the same knowledge structure.