Effects of Time Interval and Interference Manipulations on Word-Level Repetition and Naming Performance in Persons with Aphasia

Abstract

Objectives: The purpose of this paper is to investigate the impact on the repetition and naming ability of Korean aphasia patients by controlling their working memory load through time intervals and interference effects using the Temple Assessment of Language and verbal Short-term memory in Aphasia (TALSA) protocol. In addition, we examined the phonological and lexical-meaning processing abilities of persons with aphasia through word repetition tasks, nonword repetition tasks, and picture naming tasks to examine phonological and lexical-meaning production abilities. Methods: Thirteen native Korean speakers with aphasia participated in the study, along with twelve control group participants. The word and nonword repetition tasks were conducted under three conditions to examine the time delay and interference effects. Each condition entailed listening to each ten words of two and three syllables. Similarly, the picture naming tasks were carried out under three conditions involving viewing ten pictures of two and three syllables each. Results: This study examined how the repetition and naming ability of persons with aphasia, i.e., the ability to producing phonemes and lexical-meaning of persons with aphasia, varies when adjusting the working memory load under time interval and interference effect conditions. This study found that the difference in performance between groups was significant for both tasks. In particular, the larger the time interval, the greater the interference effect; that is, the greater the load of working memory, the lower the performance of aphasia subjects compared to the control group. Conclusion: Since the aphasia subjects have poor working memory ability, the results of this study indicate that as the cognitive load increases, they are more affected by the ability to process phonological and semantic activations.