Recovery of Online Sentence Processing in Aphasia: Eye Movement Changes Resulting From Treatment of Underlying Forms

Abstract

Purpose: The present study tested whether (and how) language treatment changed online sentence processing in individuals with aphasia.

Method: Participants with aphasia (n = 10) received a 12-week program of Treatment of Underlying Forms (Thompson & Shapiro, 2005) focused on production and comprehension of passive sentences. Before and after treatment, participants performed a sentence-picture matching task with active and passive sentences as eye movements were tracked. Twelve age-matched controls also performed the task once each.

Results: In the age-matched group, eye movements indicated agent-first predictive processing after hearing the subject noun, followed by rapid thematic reanalysis after hearing the verb form. Pretreatment eye movements in the participants with aphasia showed no predictive agent-first processing, and more accurate thematic analysis in active compared to passive sentences. After treatment, which resulted in improved offline passive sentence production and comprehension, participants were more likely to respond correctly when they made agent-first eye movements early in the sentence, showed equally reliable thematic analysis in active and passive sentences, and were less likely to use a spatially based alternative response strategy.

Conclusions: These findings suggest that treatment focused on improving sentence production and comprehension supports the emergence of more normal-like sentence comprehension processes.

Figures

Figure 1.

Example visual stimulus.

Figure 2.

Eye movement data in age-matched controls. N1 + Aux = subject noun and auxiliary; V = verb; NP/PP2 = postverbal noun phrase/prepositional phrase; S End = sentence end.

Figure 3.

Eye movement data in people with aphasia, all trials pre- and posttreatment. N1 + Aux = subject noun and auxiliary; V = verb; NP/PP2 = postverbal noun phrase/prepositional phrase; S End = sentence end.

Figure 4.

Eye movement data in people with aphasia, correct trials pre- and posttreatment. N1 + Aux = subject noun and auxiliary; V = verb; NP/PP2 = postverbal noun phrase/prepositional phrase; S End = sentence end.

Figure 5.

Eye movement data in people with aphasia, incorrect trials pre- and posttreatment. N1 + Aux = subject noun and auxiliary; V = verb; NP/PP2 = postverbal noun phrase/prepositional phrase; S End = sentence end.

Figure 6.

Individual treatment results: Accuracy and eye movements. The x-axis indicates the change in the proportion of correct passive sentences in the eye-tracking task from pre- to posttreatment; the y-axis indicates the change in target advantage for passive sentences in S End from pre- to posttreatment. The gray vertical and horizontal lines indicate cutoffs for improvement in accuracy (to the right of the line) and target advantage (above the line), respectively; the regression line appears in black.