Rapid Syntactic Adaptation in Self-Paced Reading: Detectable, but Only With Many Participants.

Abstract

Syntactically ambiguous sentences that are disambiguated in favor of a less preferred parse are read more slowly than their unambiguous counterparts. This is called a garden path effect. Recent self-paced reading studies have found that this effect decreased as participants are exposed to many such syntactically ambiguous sentences over the course of an experiment. This decrease has been interpreted as evidence that readers rapidly calibrate their expectations to a new environment in order to minimize their surprise when they encounter these initially unexpected syntactic structures (Fine, Jaeger, Farmer, & Qian, 2013). However, such expectation recalibration, referred to as syntactic adaptation, is only one possible explanation for the observed decrease in garden-path effect: recent studies have argued that this decrease may be driven by increased familiarity with the self-paced reading paradigm (task adaptation; Harrington Stack, James, and Watson, 2018). The goal of this paper is to tease apart these two explanations. We demonstrate that there is evidence for rapid syntactic adaptation over and above task adaptation. In a series of power analyses, we should that a large number of participants are necessary in order to have adequate power to detect this effect of syntactic adaptation. The issue of power is exacerbated in experiments designed to detect modulations of the basic syntactic adaptation effect. Such experiments are likely to be underpowered with even 1200 participants. We conclude that syntactic adaptation can in fact be detected using self-paced reading, but that other paradigms (eye-tracking) may be more effective for studying this phenomenon.

Neural Mechanisms Underlying the Dynamic Updating of Native Language

“…We address task-based adaptation versus syntactic updating in the Discussion section. For the present, we note that the most recent study on this topic concluded that syntactic updating (going beyond task practice) is detectable if a study is adequately powered (Prasad & Linzen, 2019). In all of these cases, the updated comprehension patterns were observed in adults who were mature native speakers of the language, indicating that the updating of syntactic probabilities continues beyond the acquisition that occurs in childhood.…”

“…One alternative explanation suggested in the behavioral literature is that adaptation could be happening at the level of generic task practice rather than at the level of updating the likelihood of particular sentence structures. This practice effect could be stronger for the more difficult, ambiguous sentences leading to the observed decrease in the difference between the ambiguous and unambiguous conditions (Prasad & Linzen, 2019;Stack et al, 2018). Neurally, increased facility with the task could correspond to decreased difficulty and, correspondingly, decreased activation in regions that are associated with general cognitive demands.…”

“…More broadly, exposure to uncommon sentence structures appears to facilitate subsequent processing of those sentence structures in both behavioral (Farmer, Fine, Yan, Cheimariou, & Jaeger, 2014;Wells, Christiansen, Race, Acheson, & MacDonald, 2009) and electrophysiological (Coulson, King, & Kutas, 1998) studies. (Note that there is debate about some behavioral findings and measures-specifically on whether faster reading times could reflect task-level adaptation instead of syntactic updating (Prasad & Linzen, 2019;Stack, James, & Watson, 2018). We address task-based adaptation versus syntactic updating in the Discussion section.…”

“…For the left pars opercularis, this pattern was verb-specific and did not extend to unexposed verbs, which we interpreted as demonstrating a specific effect of RC exposure rather than a generic effect of task practice. Future studies could explicitly manipulate exposure type (e.g., RC sentences versus other kinds of fillers; see Prasad & Linzen, 2019;Stack et al, 2018) in order to establish more definitively whether it is repeated experience with RC structures in particular that causes neural adaptation. Finally, replication of the Stroop correlation in a larger sample, differential correlations with different cognitive control tasks, and concomitant neuroimaging of multiple language and cognitive control tasks would allow for stronger inferences about the particular aspects of cognitive control that are related to syntactic updating and the extent to which those processes are domain-specific or general.…”

Quantifying individual differences in native and nonnative sentence processing

“…Thus, having more observations per participant will help here. Note that in some psycholinguistic tasks, including self-paced reading, participants speed-up over the course of an experiment, which attenuates ambiguity effects (Fine, Jaeger, Farmer, & Qian, 2013;Harrington Stack, James, & Watson, 2018;Prasad & Linzen, 2019). This speed-up over time may make it difficult to estimate the subject-level effect with any certainty.…”