A one-stage distributed processing account of linguistic negation

A one-stage distributed processing account of linguistic negation Stephanie Huette (shuette@ucmerced.edu), Sarah Anderson (sarah.anderson@ucmail.uc.edu), Department of Psychology, University of Cincinnati, Cincinnati, OH, 45221, USA Teenie Matlock (tmatlock@ucmerced.edu), and Michael J. Spivey (spivey@ucmerced.edu) School of Social Sciences, Humanities & Arts, University of California, Merced, Merced, CA, 95344, USA Abstract Linguistic negation can be comprehended with the inclusion (or absence) of features and categories associated with the senses in a single step. Under this view, there is no need for explicit logical operators, as the negating word or phase is treated no differently than any other word. Negation provides additional context, whereby visualizing negation as a trajectory in a distributed, grounded perceptual simulation space can easily characterize the comprehension of negated sentences. A mousetracking experiment was conducted to explore how this kind of process may be enacted in the brain and to tease apart hypotheses of logical manipulations vs. analogue signals performing this work. Keywords: language understanding, neural networks, situated cognition, mouse-tracking Introduction Negation occurs in all languages and is is an important part of everyday communication. Humans need it to express situations in which an object, person, state, or event is not present or even non-existent. Negation can be coded in a variety of ways. In some cases, it is expressed suprasegmentally, for instance, in sarcastic remarks such as “I sure excelled in that class,” said by a student who just learned that his course grade was a D. It can also be coded with affixes, such as the prefix “non-“, as in “The nonexistence of rules worries me. ” It can also be coded with words such as “not”, “none”, and “without”. Despite the ubiquity of negation, its processing has perplexed philosophers for centuries. There is still a relatively poor understanding of how people contend with the meaning of simple negated statements such as “The eagle is not in the sky”. The processes that underlie the comprehension of a negated utterance has generated recent interest among psycholinguists. In pioneering work, Kaup, Yaxley, Madden, Zwaan, and Ludtke, (2006) presented participants with sentences like, “The eagle was not in the sky,” then presented an accompanying picture. Participants had to respond whether the content of the picture had been mentioned in the sentence they had just read. The reasoning was that if participants perceptually simulate negation in the same way they simulate affirmative sentences, they should be quicker to respond “yes” to pictures that match the sentence (e.g., an eagle with its wings folded). Kaup and colleagues found that when participants read negated sentences, response times to a picture that matched the affirmative version of the proposition (eagle with wings spread) were faster than to a picture that actually matched the negated sentence, suggesting that a perceptual simulation of the affirmative proposition was created in response to negated sentences. The researchers then suggested that negation may be handled through a separate, special process, not through a perceptual simulation. Thus, the timecourse of understanding a negated sentence is not well understood. There are three possibilities as to how a final interpretation of the negation comes to be activated (Figure 1). The first possibility is a logical process discretely revises a fully activated affirmative interpretation (1A). The second scenario predicts a lag in activation of a negated sentence, simply because negation is more complex (1B). The third hypothesis is negation produces increased competition amongst the possible features the negated meaning could activate, forcing negation to be slower at first, but once one interpretation begins to form, making negation much faster compared to the affirmative version (1C). Note that this last hypothesis predicts only speed differences, and no spatial differences. Figure 1: Each hypothesis shows predicted mouse trajectories on a computer screen. Each of these panels in Figure 1 can be thought of in terms of velocity: the speed and direction in which an interpretation is formed will be shared with motor systems during a response (Spivey, Grosjean & Knoblich, 2005). Thus, spatial and velocity metrics of a computer mouse will reveal which of the aforementioned hypotheses can best explain how a negated interpretation is formed. In addition, a proof of concept model was created as a fundamental first