Comprehension of famous personal and geographical names in global aphasic subjects

The Processing Differences between Chinese Proper Nouns and Common Nouns in the Left and Right Hemispheres of the Brain

In this study, we investigated whether there were differences between the processing of Chinese proper nouns and common nouns in the left and that in the right hemispheres of the brain by using a visual half-field technique. The experimental materials included four types of proper nouns (people’s names, landmark names, country names, and brand names), four types of common nouns (animals, fruits and vegetables, tools, and abstract nouns), and pseudowords. Participants were asked to judge whether target words that had been quickly presented in their left or right visual field were meaningful words. The results showed that there was a distinction between the processing of the two types of words in the left and right hemispheres. There was no significant difference in the processing of the two types of nouns in the right hemisphere, but the left hemisphere processed common nouns more effectively than proper nouns. Furthermore, the processing difference of proper nouns between the two hemispheres was less than that of common nouns, suggesting that proper nouns have a smaller lateralization effect than common nouns.

Cerebral processing of proper and common nouns: Perception and production following left hemisphere damage

The goal of this study was to further investigate hemispheric specialization for proper and common nouns by examining the ability of individuals with left hemisphere damage (LHD) to perceive and verbally reproduce famous names and matched common names compared with the performance of matched healthy controls (HC). Ten individuals with LHD due to stroke and 16 age- and education-matched HC completed recognition and production tasks of famous proper and common nouns. All tasks were designed as split-visual field experiments, modelled after the study done by Ohnesorge and Van Lancker. Results contribute to a better understanding of hemispheric roles in perception and production of famous proper nouns, suggesting that (1) both hemispheres can recognize famous proper nouns, possibly due to a right hemisphere role in personal relevance and (2) production of proper nouns as well as common nouns is associated with left hemisphere.

Proper name anomia after right-hemispheric lesion: a case study

This study describes the case of CH, a 68-year-old left-handed woman who suffered a right temporo-parieto-occipital infarct in the territory of the middle cerebral artery and who exhibits severe proper name anomia. During the acute stage, CH was diagnosed with severe amnestic aphasia (Aachen Aphasia Test). Her lesion mirrors those of left hemisphere impairing the processing proper names, without an aphasic language disorder in general. Seven weeks later, language improved to a mild amnestic aphasia that currently does not interfere with her daily life. However, the use of proper names in both the visual and auditory modalities was still impaired and showed no improvement after 6 months of speech therapy. While not being able to name family members or familiar persons, she was, however, still able to describe the persons' backgrounds along with some additional semantic information. Furthermore, in a simple semantic design test, CH was selectively impaired in correctly classifying proper names into their respective word classes. Conversely, she was able to correctly name and classify other word categories (e.g., common nouns). In the subsequent study, we assessed the modalities "auditory comprehension," "picture naming," and "reading comprehension" and classified her responses in the categories "correctly named," "correctly classified," "correctly described attributes" (e.g., occupation) and "falsely named." The results were compared with those of an age-matched healthy control group. In the visual task, CH correctly named 80% of the visualized objects, 3% of the familiar persons and 15% of the familiar city views.

Sparing of written production of proper nouns and dates in aphasia

Aphasia is a total or partial loss of the ability to produce or understand language, usually caused by brain disease or injury. In this case study, the aphasic patient (BMW) has a profound impairment of oral production and a very moderate impairment in comprehension. Several years of informal observation lead to the current study that contrasts written naming of common nouns to written naming of proper nouns and dates. BMW named professional ice hockey players, team logos, and provided birthdays of players with near perfect accuracy and normal rates of production. In contrast, his performance on naming common nouns was only 50% accurate and appeared very laborious. The results of this study thus show a clear preservation of date and proper noun production in contrast to common nouns.

Cerebral laterality for famous proper nouns: visual recognition by normal subjects

Lexical processing has long been associated with left-hemisphere function, especially for infrequently occurring words. Recently, however, persons with severe aphasia, including word-recognition deficits, were observed to recognize familiar proper nouns. Further, some patients suffering right-hemisphere damage were poorer at identifying famous names than left-hemisphere-damaged subjects. These observations point to the possibility that some property of the right hemisphere provides an advantage for the processing of familiar or personally relevant stimuli. To investigate this possibility, we conducted split-visual-field studies in which we manipulated stimulus sets, recognition task, and exposure duration. Greater accuracy in the right visual field was found for common nouns and unknown proper nouns, and famous proper nouns were overall more accurately recognized. Performance for famous nouns in the two visual fields was not significantly different when the task required categorization into famous or nonfamous and when stimuli most highly rated as familiar were used. These findings support our proposals that (1) both hemispheres can process famous proper nouns and (2) the right hemisphere is specialized for personal relevance.