Pupillometry reveals increased pupil size during indirect request comprehension

Abstract

Fluctuations in pupil size have been shown to reflect variations in processing demands during lexical and syntactic processing in language comprehension. An issue that has not received attention is whether pupil size also varies due to pragmatic manipulations. In two pupillometry experiments, we investigated whether pupil diameter was sensitive to increased processing demands as a result of comprehending an indirect request versus a direct statement. Adult participants were presented with 120 picture-sentence combinations that could be interpreted either as an indirect request (a picture of a window with the sentence "it's very hot here") or as a statement (a picture of a window with the sentence "it's very nice here"). Based on the hypothesis that understanding indirect utterances requires additional inferences to be made on the part of the listener, we predicted a larger pupil diameter for indirect requests than statements. The results of both experiments are consistent with this expectation. We suggest that the increase in pupil size reflects additional processing demands for the comprehension of indirect requests as compared to statements. This research demonstrates the usefulness of pupillometry as a tool for experimental research in pragmatics.

Speech Planning at Turn Transitions in Dialog Is Associated With Increased Processing Load

“…The analysis of task-evoked pupillary responses allows studying differences in task demands, that is, the amount of overall cognitive resources that need to be allocated in order to master a task (Hess & Polt, 1964;Kahneman, 1973;Laeng, Sirois, & Gredeb€ ack, 2012). Most studies using task-evoked pupillary responses to measure processing load in language processing have focused on comprehension (Engelhardt, Ferreira, & Patsenko, 2010;Just & Carpenter, 1993;Koch & Janse, 2016;Kuchinke, Vo, Hofmann, & Jacobs, 2007;Schmidtke, 2014;Tromp, Hagoort, & Meyer, 2016;Zekveld, Kramer, & Festen, 2010, inter alia), and there are only a few studies that have investigated language production (Papesh & Goldinger, 2012;Sauppe, 2017). If planning in overlap leads to increased processing load, taskevoked pupillary responses should have larger amplitudes as compared to planning in silence, whereas they are not predicted to differ if overlap does not increase processing load during response planning.…”

The Frequency of Rapid Pupil Dilations as a Measure of Linguistic Processing Difficulty

“…Pupil size has long been known to reflect arousal [ 1 ] and cognitive load in a variety of different tasks such as arithmetic problems [ 2 ], digit recall [ 3 ], attention [ 4 ] as well as language complexity [ 5 – 9 ], grammatical violations, context integration effects [ 10 ] and recently even pragmatic effects [ 11 ]. All of these studies have looked at the overall effect of pupil dilation; however, raw pupil dilation as a measure of cognitive load is always at risk of confounding the load reflex with the light reflex, especially in settings where the visual surroundings change or where the screen cannot in all conditions be fully controlled for luminosity of all objects on the screen (note also that the light reflex can even pose a problem in constant lighting conditions, because the pupil exhibits irregular oscillation under the influence of constant light).…”

People with larger social networks are better at predicting what someone will say but not how they will say it

“…Additionally, it has been found to increase upon reading or hearing incongruent or more complex linguistic material (e.g. Hyönä, Tommola, & Alaja, 1995;Just, Carpenter, & Miyake, 2003;Tromp, Hagoort, & Meyer, 2016) and it positively correlates with a word's surprisal (Frank & Thompson, 2012). Therefore, the degree to which listeners exhibit pupil dilation reflects to what degree the incoming input fits with their prediction or deviates from it.…”