Articulation rate as a means of distributing information and its effect on the N400-component

Sammanfattning: Information theoretical approaches to language state that the most efficient communication oc­curs when the amount of information transmitted is distributed as uniformly as possible over time. Previous research has shown that speakers tend to adhere to strategies for distributing information efficiently, using mechanisms at multiple linguistic levels. This study aims to in­vestigate whether articulation rate (AR) is used in continuous speech to achieve a more uniform distribution of information within sentences, quantified as surprisal estimated by the state­-of-­the-­art language model GPT-­2, and if this has an effect on the amplitude of the N400 brain response in listeners. In neurolinguistics, surprisal has been observed to be a good predictor of the N400, which is related to processing of semantics and meaning in general. The results showed a significant, though small, effect of surprisal on AR, indicating that AR may have some role in achieving more uniform distribution of information on the word level. In line with previous research, surprisal showed an effect on the N400 where higher surprisal led to larger amplitudes. Results regarding AR and distributional effects on the N400 were inconclusive, although some independent effects of AR were found that could be further explored in more controlled experimental settings.