Decision Making by People With Aphasia: A Comparison of Linguistic and Nonlinguistic Measures

Purpose Decision making involves multiple cognitive and linguistic processes. The extent to which these processes are involved depends, in part, on the conditions under which decision making is assessed. Because people with aphasia (PWA) have impaired language abilities and may also present with cognitive deficits, they may have difficulty during decision-making tasks. Yet little research exists on the decision-making abilities of PWA. Thus, the purposes of this study were to investigate the performance of PWA on linguistic and nonlinguistic decision-making measures and to explore the relationship between decision making and cognitive test performance. Method A quasi-experimental design was used to compare the performance of PWA ( n = 16) and age- and education-matched control participants ( n = 16) on three decision-making tasks: Making a Decision subtest from the Functional Assessment of Verbal Reasoning and Executive Strategies (linguistic decision-making task), Iowa Gambling Task (nonlinguistic decision-making task with ambiguity), and Game of Dice Task (nonlinguistic decision-making task without ambiguity). Participants also completed assessments of language, working memory, and executive functions. Scores on the three decision-making tasks were compared between groups, and cognitive influences on decision-making performance were examined using correlation analyses. Results PWA differed significantly from control participants on linguistic decision making, particularly when required to verbalize their rationale for making their decision. PWA and control participants did not differ significantly on measures of nonlinguistic decision making. Performance on multiple cognitive measures was correlated with performance on the linguistic reasoning task, as well as one of the nonlinguistic tasks (Game of Dice Task). Conclusions Decision-making tasks that are heavily dependent on language, such as those used in capacity assessments, may disadvantage PWA. Assessments of decision-making capacity should include communication supports for people with acquired communication disorders; further investigation in the areas of decision making and aphasia is needed.

Decision-Making Impairments in Patients with Parkinson’s Disease

A high percentage of Parkinson’s disease (PD) patients show cognitive impairments in addition to the cardinal motor symptoms. These deficits primarily concern executive functions most probably linked to dysfunctions in prefrontal regions due to decreased dopaminergic transmission in fronto-striatal loops. To investigate possible associations between decision-making and executive functions in PD, we examined 20 non-demented PD patients and 20 healthy control subjects with a neuropsychological test battery and the Game of Dice Task. In this computerised decision-making task, the rules for gains and losses and the winning probabilities are obvious and stable. Thus, strategic components besides feedback processing might influence decision-making in this task. We found that PD patients were impaired in the Game of Dice task performance and that the frequency of disadvantageous choices correlated with both executive functions and feedback processing. We suggest that decision-making deficits of PD patients in explicit gambling situations might be associated with dysfunctions in two different fronto-striatal loops: the limbic-orbitofrontal-striatal loop, involved in feedback processing, and the dorsolateral prefrontal-striatal loop, involved in executive functions.