Retrieving semantic information and names of proper and common nouns in people with and without aphasia

Objectives: The aim of this study was to determine whether performance differs between proper nouns and common nouns in semantic and naming tasks between patients with aphasia and normal adults. Methods: 20 patients with aphasia and 20 normal adults performed a proper noun semantic task, common noun semantic task, proper noun naming task, and common noun naming task. Following this, we compared the scores and analyzed the correlation among the four tasks. Results: The differences among the groups and the types of tasks were statistically significant, but not according to the noun types. Also, noun type and group interaction effect were not statistically significant; but task type and group, noun type and task type, and noun type, task type and group interaction effect were significant. In the aphasia group, there was a significant correlation between the performance of all tasks, and the correlation coefficient between the proper noun semantic task and the common noun semantic task was very high. Conclusion: In the aphasia group, we confirmed that the proper noun score was significantly better than the common noun when performing semantic tasks. This study suggests that in the case of proper nouns, the function of the right hemisphere; that is, the activation of visual information, may be involved in semantic processing. As a result, it suggests that aphasia patients with damaged left hemispheres were assisted in the process of proper noun semantics by using the uninjured right hemisphere.