When you call a dog an animal: Context effects in categorization tasks Jan-Rouke Kuipers, Wido La Heij [Part of the work in collaboration with Albert Costa] Whereas current models of speech production seem reasonably successful in accounting for context effects in basic-level object naming, they provide no, or unsatisfactory explanations for context effects observed in superordinate-level and sub-ordinate level naming. Recently, we examined a finding that seems particularly problematic: the observation that basic-level names of objects - contrary to the prediction of a number of models of speech production - facilitate the naming of the corresponding object at the superordinate (category) level. For instance, the basic-level context word "dog" facilitates the categorization of the picture of a dog as "animal", despite the fact that the word "dog" can be viewed as a strong competitor at the level of lexical selection. In order to account for the fact that speakers can address objects in many different ways (e.g., a dog may be referred to as 'dog', 'animal', 'pet', 'puppy' or 'Pluto'), we first propose to reintroduce Levelt's (1989) process of "conceptualization", in which a "preverbal message" is constructed on the basis of (a) the conceptual representation(s) activated by the target stimulus and (b) the speaker's communicative intention (in laboratory conditions defined by the task instruction). In addition, we propose that this process of conceptualization is the main (possibly only) process that is affected by task instruction. In the resulting model, context stimuli may affect at least three processing stages in object naming: (1) target identification, (2) conceptualization (generation of a preverbal message) and (3) lexical selection. More specifically, a context stimulus may (a) facilitate target identification when it belongs to the same semantic category, (b) delay lexical selection to the degree in which it activates a competing word and - most importantly - (c) it may facilitate the generation of a preverbal message when it is "message congruent". Message congruency is defined as the situation in which target and context lead to the same preverbal message, given the current task instruction. For example, in a categorization task, the target picture of a dog and the word "dog" lead to the same preverbal message ANIMAL. In two series of experiments we tested these proposals. First, we obtained evidence that correct basic level names (e.g., "dog") do compete with the category name (e.g., "animal") at the lexical level, confirming our proposal that task instruction does not affect lexical selection. Second, we showed that the facilitation effect induced by correct basic-level names in categorization tasks cannot be attributed to a strong facilitation effect at the level of target identification. On the basis of these findings, we conjectured that the overall facilitation effect induced by correct basic-level names has to be due to a large message-congruency effect. Therefore, in a final series of experiments, we attempted to estimate the size of the effect of message-congruency. This was achieved by studying the effect of a context picture in naming and categorizing tasks. Under the assumption that context pictures do not induce lexical competition (cf. Bloem & La Heij, 2003; Bloem, van den Boogaard & La Heij, in press), the results of these experiments confirmed that the message-congruency effect is large enough to outweigh an interference effect at the level of lexical selection. We conclude that the reintroduction of a process of conceptualization (a) provides an explanation for our flexibility in object naming and (b) allows for an attractive explanation of facilitation effects in categorization tasks in terms of "message congruency". References Bloem, I. & La Heij, W. (2003). Semantic facilitation and semantic interference in word translation: Implications for models of lexical access in language production. Journal of Memory and Language, 48, 468-488 Bloem, I, van den Boogaard, S., & La Heij, W. (in press). Semantic facilitation and semantic interference in language production: Further evidence for the Conceptual Selection Model of lexical access. Journal of Memory and Language. Levelt (1989). Speaking: From intention to articulation. Cambridge, MA: MIT Press.