What matters in semantic feature processing for persons with stroke-aphasia: Evidence from an auditory concept–feature verification task

Abstract

Background The relationship between object concept domains (living vs. nonliving) and their underlying feature structures is a frequent area of investigation regarding semantic processing in healthy individuals and some individuals with neuropsychological impairment resulting from herpes simplex encephalitis, semantic dementia and Alzheimer's disease. However, this relationship has been less well-investigated in persons with stroke-aphasia (PWA), even though many treatments for anomia following stroke are predicated on the use of semantic feature cues. Aims As part of a larger investigation into the influence of semantic feature processing on naming for PWA, this study examined the ability of PWA to confirm the relations between object concepts and associated semantic features. Methods & Procedures 15 native English-speaking, right handed individuals with post-stroke-aphasia responded yes or no via button press to feature-verification questions designed to probe the relationships between concept domain and feature type and distinctiveness. Outcomes & Results PWA were more accurate and quicker to confirm concept-feature relationships when features contained function/action, rather than visual-perceptual, information about concepts and when features were distinctive to concepts rather than shared. The truthfulness (i.e., veracity) of concept-feature pairings was demonstrated to differentially affect living versus nonliving concepts. Within domain, only nonliving concepts were verified more accurately and more quickly when pairings were true (rather than false). Between domains, true nonliving concept-feature pairings were more accurately and more quickly verified than true living concept-feature pairings. Also with respect to veracity, correlations were observed between aphasia severity and accuracy and speed of response to false concept-feature pairings. Conclusions Findings have implications for the way in which semantic processing is probed with PWA, as well as providing preliminary information regarding responsivity of PWA to differing types of semantic information for living versus nonliving concepts. The fact that PWA demonstrated disproportionate difficulty responding to certain types of semantic information also suggests preliminary implications for the utility of different types of semantic cues in semantically-based treatments for word retrieval impairment.

Verbal Description of Concrete Objects: A Method for Assessing Semantic Circumlocution in Persons With Aphasia

“…For PWA, we observed a role for the provision of distinctive features for adequate description of objects, a feature type that may be particularly difficult to access for some individuals with aphasia (e.g., Mason-Baughman & Wallace, 2014). In addition, it may be that we need to examine these relationships from a more finely grained perspective, both with respect to more discrete feature typeconcept relationships (e.g., fruit: visual-perceptual color, animal: visual-perceptual form) and across performance of persons with aphasia with different lesion profiles (e.g., Gainotti, 2006; see also Antonucci, 2014aAntonucci, , 2014b.…”

“…Stimuli were 36 concrete objects selected from a larger set of 60 (Antonucci, 2014b). To avoid fatigue effects, each participant responded to either set A or set B, each of which comprised half of the selected stimuli (i.e., nine living and nine nonliving).…”

“…One robust finding is that difficulty processing distinctive feature knowledge is linked both to the ability to distinguish among semantically related concepts and to word retrieval (MasonBaughman & Wallace, 2013, 2014Wallace & MasonBaughman, 2012). Work in our own lab with PWA further highlights the importance of distinctive feature cues for accurately verifying concept-feature relationships as well as their importance in sufficiently describing objects such that a communication partner would be likely to identify the item being described in the absence of its label (Antonucci, 2014a(Antonucci, , 2014b.…”

Semantic knowledge use in discourse produced by individuals with anomic aphasia

“…However, Antonucci (2014) demonstrated that some PWA have impaired access to certain types of knowledge more than others. Yet, all these studies used single concepts.…”

“…This may present as a differential access to certain types of features (Antonucci, 2014; Marques, Mares, Martins, & Martins, 2013; Mason-Baughman & Wallace, 2014; Thompson & Jefferies, 2013). To date, researchers have not investigated whether modality-specific features differ in PWA and healthy controls, and while several researchers have examined how semantic feature based treatment influences discourse (Boyle, 2004; Peach & Reuter, 2010; Rider, Wright, Marshall, & Page, 2008), none have investigated how semantic knowledge types are used within discourse.…”