Pragmatic comprehension deficit in Parkinson's disease

Abstract

Recognizing the specific speech act (Searle, 1969) that a speaker performs with an utterance is a fundamental feature of pragmatic competence. However, little is known about neurocognitive mediation of speech act comprehension. The present research examined the extent to which people with Parkinson's Disease (PD) comprehend specific speech acts. In the first experiment, participants read conversational utterances and then performed a lexical decision task (decide whether a target string of letters is a word). Consistent with past research, non-impaired participants performed this task more quickly when the target string was the speech act associated with the preceding utterance. In contrast, people with Parkinson's disease did not demonstrate this effect, suggesting that speech act activation is slowed or is not an automatic component of comprehension for people with PD. In a second study, participants were given unlimited time to indicate their recognition of the speech act performed with an utterance. PD participants were significantly poorer at this task than were control participants. We conclude that a previously undocumented language disorder exists in PD and that this disorder involves a selective deficit in speech act comprehension. Frontostriatal systems (the systems impaired in PD) likely contribute to normal speech act comprehension. Pragmatic Comprehension Deficit in Parkinson's DiseaseAlthough Parkinson's Disease (PD) is primarily associated with debilitating extrapyramidal motor dysfunction, PD also affects thinking, reasoning, planning and language functions. The nature of the language-related deficits of PD have been hotly debated, but, with the partial exception of the attentional and short-term memory related sentence processing deficit, (Lieberman et al., 1990;Grossman et al, 1992;Grossman, 1999) they are largely understudied. In particular, impairment in the domain of pragmatics has not yet been studied adequately.Pragmatics refers to the use of language in social contexts (e.g., knowing what to say and when to say it, correctly interpreting another person's meaning, etc.). Recent evidence suggests that people with PD are impaired in certain pragmatic abilities such as conversational fluency/ appropriateness and topic-coherence (McNamara & Durso, 2003), inferencing and humor appreciation (Berg, Bjornram, Hartelius, Laakso, & Johnels, 2003;Bhat, Iyengar & Chengappa, 2001) and the interpretation of figurative language (Lewis, Lapointe, Murdoch & Chenery (1998). However, the extent and the nature of pragmatic impairment are unclear. Importantly, examining the nature of the pragmatic impairment in PD may yield clues as to the underlying neurobiology and cognitive architecture of pragmatic competence itself. And clinically it is important to study pragmatic competence in PD because pragmatic dysfunction may be a key component of both the communication disorders associated with PD and the social-cognitive and behavioral disorders of PD. In this research we investigated the ability of people...

Communication impairment in patients with Parkinson's disease: challenges and solutions

“…However, the PD participants did not exhibit this priming effect, suggesting that speech act activation is slowed or is no longer an automatic component of comprehension. 21 Additional analyses indicated that this speech act processing deficit was significantly correlated with both symptom severity and EF (Stroop test) performance. 21 In a follow-up study, the same participants read scenarios and utterances and were asked to provide a single word that they believed best described the action the speaker was performing.…”

“…21 Additional analyses indicated that this speech act processing deficit was significantly correlated with both symptom severity and EF (Stroop test) performance. 21 In a follow-up study, the same participants read scenarios and utterances and were asked to provide a single word that they believed best described the action the speaker was performing. PD participants correctly identified significantly fewer speech acts than did the control participants, demonstrating a deficit in speech act recognition in PD that is independent of temporal constraints.…”

“…19 In addition to nonliteral language, pragmatic meaning comprehension can also refer to illocutionary force or what a speaker intends to achieve with an utterance. 22 Holtgraves and McNamara 21 investigated PD patients' speech act comprehension by having nondemented PD patients and age-matched controls perform a timed lexical decision task following an utterance that performed a specific speech act (ie, beg) or a matched utterance that did not perform that speech act. Participants in the control group exhibited the expected priming for the action verb after the speech act utterance.…”

“…[19][20][21] As some degree of shared understanding of a recipients' utterance is essential for successful language use, early deficits in this domain should be examined when determining early diagnosis and strongly considered when approaching conversations.…”

“…51 In this approach, language users are assumed to be attentive to situation-based interpersonal considerations and structure their utterances so as to be responsive, to varying degrees, to these considerations. Holtgraves and McNamara 21 used politeness theory to examine the possibility that individuals with PD might suffer a deficit in terms of conversational appropriateness. Using a role-playing methodology, PD and healthy controls were asked to indicate what they would say in various situations in which request imposition and power were manipulated.…”