Tuesday, February 26, 2008
Syntactic and phonological abilities in semantic dementia
One of the big take-home messages from the last set of readings on semantic dementia, is that these patients indeed seem to have relatively spared syntactic and phonological abilities. In one case, reported by Saffran & Schwartz (1994), the patient could perform grammaticality judgments, showed a normal advantage for structured over scrambled sentences in a word monitoring task (but was insensitive to semantically anomalous items unlike controls), and was able to use syntactic information to identify noun referents. McCarthy & Warrington (2001, Neurocase, 7:77-87) report another case in which semantic knowledge was severely affected, yet digit span was normal, and in a variety of repetition tasks showed normal sensitivity to phonological factors and lexicality, but insensitivity to semantic factors. Detailed reports like these, coupled with the more standard language assessment tests reported in the group studies we’ve read over during the last few weeks, strongly suggests that syntactic and phonological abilities are relatively spared in SD patients.