
Psychology Publications
Document Type
Article
Publication Date
1-1-2023
Journal
PLoS One
Volume
18
Issue
2
First Page
1
Last Page
32
URL with Digital Object Identifier
https://doi.org/10.1371/journal.pone.0262504
Abstract
Verb and action knowledge deficits are reported in persons with Parkinson's disease (PD), even in the absence of dementia or mild cognitive impairment. However, the impact of these deficits on combinatorial semantic processing is less well understood. Following on previous verb and action knowledge findings, we tested the hypothesis that PD impairs the ability to integrate event-based thematic fit information during online sentence processing. Specifically, we anticipated persons with PD with age-typical cognitive abilities would perform more poorly than healthy controls during a visual world paradigm task requiring participants to predict a target object constrained by the thematic fit of the agent-verb combination. Twenty-four PD and 24 healthy age-matched participants completed comprehensive neuropsychological assessments. We recorded participants' eye movements as they heard predictive sentences (The fisherman rocks the boat) alongside target, agent-related, verb-related, and unrelated images. We tested effects of group (PD/control) on gaze using growth curve models. There were no significant differences between PD and control participants, suggesting that PD participants successfully and rapidly use combinatory thematic fit information to predict upcoming language. Baseline sentences with no predictive information (e.g., Look at the drum) confirmed that groups showed equivalent sentence processing and eye movement patterns. Additionally, we conducted an exploratory analysis contrasting PD and controls' performance on low-motion-content versus high-motion-content verbs. This analysis revealed fewer predictive fixations in high-motion sentences only for healthy older adults. PD participants may adapt to their disease by relying on spared, non-action-simulation-based language processing mechanisms, although this conclusion is speculative, as the analyses of high- vs. low-motion items was highly limited by the study design. These findings provide novel evidence that individuals with PD match healthy adults in their ability to use verb meaning to predict upcoming nouns despite previous findings of verb semantic impairment in PD across a variety of tasks.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
S1 Table. Norming Studies Participant Demographics
pone.0262504.s002.pdf (274 kB)
S2 Table. Neuropsychological Battery.
pone.0262504.s003.pdf (170 kB)
S5 Table. Predictive Sentences Practice.
pone.0262504.s004.pdf (182 kB)
S6 Table. Predictive Sentences, Full Trials (Sets 1-12).
pone.0262504.s005.pdf (165 kB)
S7 Table. Baseline Sentence Practice.
pone.0262504.s006.pdf (169 kB)
S8 Table. Baseline Trials.
pone.0262504.s007.pdf (252 kB)
S9 Table. Analyses of PD versus control gaze logits to the target object during predictive sentences.
pone.0262504.s008.pdf (250 kB)
S10 Table. Analyses of PD versus control gaze logits to the agent-related object during the predictive window.
pone.0262504.s009.pdf (251 kB)
S11 Table. Analyses of PD versus control gaze logits to the verb-related object during the combined verb + target window.
pone.0262504.s010.pdf (260 kB)
S12 Table. Effect of motion content on gaze logits to the target entity during predictive sentences.
pone.0262504.s011.pdf (253 kB)
S13 Figure. Looks to target versus distractor images in predictive sentences, in logits.
pone.0262504.s012.pdf (269 kB)
S14 Figure. Looks to target versus distractor images in baseline sentences, in logits.
pone.0262504.s013.pdf (180 kB)
S3 Appendix. Visual Stimuli Selection and Editing.
pone.0262504.s014.pdf (311 kB)
S4 Appendix. Word Onsets in Sentence Audio.