Typicality-based semantic treatment for anomia results in multiple levels of generalisation

ABSTRACT

This study investigated the effects of typicality-based semantic feature analysis (SFA) treatment on generalisation across three levels: untrained related items, semantic/phonological processing tasks, and measures of global language function. Using a single-subject design with group-level analyses, 27 persons with aphasia (PWA) received typicality-based SFA to improve their naming of atypical and/or typical exemplars. Progress on trained, untrained, and monitored items was measured weekly. Pre- and post-treatment assessments were administered to evaluate semantic/phonological processing and overall language ability. Ten PWA served as controls. For the treatment participants, the likelihood of naming trained items accurately was significantly higher than for monitored items over time. When features of atypical items were trained, the likelihood of naming untrained typical items accurately was significantly higher than for untrained atypical items over time. Significant gains were observed on semantic/phonological processing tasks and standardised assessments after therapy. Different patterns of near and far transfer were seen across treatment response groups. Performance was also compared between responders and controls. Responders demonstrated significantly more improvement on a semantic processing task than controls, but no other significant change score differences were found between groups. In addition to positive treatment effects, typicality-based SFA naming therapy resulted in generalisation across multiple levels.

KEYWORDS:

• Aphasia
• Generalisation
• Typicality
• Rehabilitation

Acknowledgments

The authors thank Stefano Cardullo and Rachel Ryskin for their knowledge regarding mixed-effects models and R; Carrie Des Roches for her contributions to the project; and many others for their assistance in data collection.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 Participants were recruited from the Chicago area as the Center for the Neurobiology of Language Recovery project was multi-site in nature. The same study procedures were followed for all participants.

2 Due to minor changes in study protocols over the course of the experiment, BUc07 did not receive Part Two of the WAB-R, which is necessary for computing the WAB-LQ and CQ; and BUc01, BUc02, and BUc08 were not given the BNT during the natural history phase. Thus, these patients were excluded from analyses using scores from those assessments.

3 Of note, two treatment participants (i.e., BU06 and BU07) were excluded from analysis of the Syllable Judgment tasks because the response configuration (i.e., two- versus three-button response) differed at pre- and post-treatment time points for these participants. Additionally, one treatment participant was excluded from the Superordinate Category Verification analysis (i.e., BU11) and another participant from the Semantic Feature Verification analysis (i.e., BU12) because they did complete the task at both time points. Lastly, BUc05, BUc07, BUc08, and BUc10 did not receive the semantic and phonological processing tasks before and after a no-treatment period and thus, were excluded from those analyses.

Additional information

Funding

This project is funded by NIH/NIDCD [grant number P50DC012283 and T32DC013017]; Christopher A. Moore [grant number T32DC013017]; Cynthia K. Thompson [grant number P50DC012283].