A study of semantic treatment of three Chinese anomic patients

Abstract

A treatment combining semantic feature analysis and semantic priming was carried out on three Cantonese-speaking brain-injured individuals with word-finding difficulties. Two of the participants with mild to moderate semantic impairment demonstrated significant progress on naming performance. Treatment effects also generalised to semantically related and unrelated untrained items. However, only one of these two participants was able to maintain the treatment gain for at least one month after the therapy was completed. The third patient with severe semantic deficits did not benefit from the intervention. The different outcomes of these participants to the same intervention were explained in terms of the nature of the treatment approach, the patients' underlying language deficits, and their level of cognitive abilities.

Acknowledgments

This study was supported by a grant from the Simon K. Y. Lee Research Fund. We are grateful to YKM, YSH, and MTK for their participation.

Notes

¹In the Chinese language family, there are seven dialect groups. Cantonese belongs to the Yue dialect group, which is different from the Mandarin group (Li & Thompson, 1981). Although speakers of different dialects may not understand each other through speech, they can by and large communicate through written language.

²Only culturally appropriate items were used for oral naming and non-verbal semantic tests. The criteria for selection were based on the performance of 30 female and 30 male Hong Kong Cantonese speakers equally distributed in three age groups: 25–39, 40–59, and > 60 years of age, and two educational levels, < 13 years and ≥ 14 years of schooling. An arbitrary cutoff of 80% correct or higher was used for oral naming, and the criterion of at least 70% correct was adopted for the two non-verbal semantic tests. A total of 217, 23, and 37 items were then chosen from the Snodgrass and Vanderwart picture set, BORB, and PPTT, respectively.

³The test has four parts, immediate recall, immediate recall after distraction, delayed recall and delayed recognition. The experimenter first reads aloud a sequence of 15 monosyllabic or bisyllabic Chinese words a total of five times. The subject has to repeat as many words as possible after each presentation. The experimenter then presents a distractor set of 15 words once and the subject is asked to repeat it. Thirty minutes later, the subject has to recall the words in the target set (i.e., the ones that were presented five times) for delayed recall. For delayed recognition, the experimenter presents a total of 50 words, one at a time, including items in the target set, those in the distractor set, and 20 words that are either semantically related or phonologically similar to words in the two sets. The subject has to decide for each word whether it belongs to the target set.

⁴Five of MTK's errors in spoken word–picture matching and all his errors in written word–picture matching involved choosing the semantic distractor.

⁵YSH chose the semantic distractor six times in spoken word–picture matching and five times in written word–picture matching.

⁶During the first six sessions of this treatment study, i.e., the baseline sessions and the first three treatment sessions, we noticed that YSH had a tendency to finger trace some characters when she experienced difficulties in orally naming the target objects. Upon her request, she was provided with pencil and paper starting from the fourth treatment session. This modification to the procedure did not seem to result in any discernible changes in her naming performance from sessions 3 to 4 (see Figure 2).

⁷Previous studies have shown that age of acquisition greatly influences object naming latencies in normal individuals (e.g., Barry, Morrison, & Ellis, 1997; Ellis & Morrison, 1998; Morrison, Ellis, & Quinlan, 1992), and is a powerful predictor of naming accuracy in aphasic(Continued overleaf)patients (e.g., Cuetos, Aguado, Izura, & Ellis, 2002; Ellis, Lum, & Lambon Ralph, 1996; Feyereisen, Van der Borght, & Seron, 1988; Nickels & Howard, 1995). However, similar to other treatment studies, there were constraints on the selection of available stimuli for assignment to different probe types in the present investigation; it was not possible for us to manipulate familiarity while controlling for age of acquisition. In order to see whether the familiarity ratings of the probe items were confounded with age of acquisition, normal subjects were invited to estimate the age at which they first learned each item. Rather than collecting such information from individuals of college age as usually done, we believe that it is more appropriate to ask subjects who are matched in age and education with the anomic participants to give age estimates. It was found that older normal subjects, i.e., controls of YKM and YSH, experienced great difficulties in doing so. More meaningful estimates were obtained only from the control of MTK. As it turned out, MTK was the only case in this study where the effect of familiarity on naming could be examined. The mean ages of acquisition (and standard deviation) for high and low familiarity treated, generalisation, and control probes were 5.67 (1.54) for high-treated, 5.93 (1.03) for low-treated, 5.27 (1.62) for high-generalisation, 6.07 (0.83) for low-generalisation, 5.00 (0.67) for high-control, and 8.70 (2.26) for low-control. The differences between high and low familiarity stimuli with respect to age of acquisition for treated and generalisation items were insignificant, but there was a significant difference among the control items (p < .001). This was mainly due to the low familiarity control items from the category of musical instruments.