Recent research in the evolution of language has focused on a search for prelinguistic cognitive abilities which may have been co-opted by the emerging language faculty. One recent suggestion is that subitizing, or the primate and infant human ability to identify and keep track of small sets of participants without counting, may have played a role in the evolution of syntax (Hurford in press, Hauser et al 2000). If this is indeed the case, we may expect to find populations with linked impairments both in the processing of syntactic argument structure and their ability to subitize.
This paper reports the results of a pilot study which seeks to test this hypothesis. A small cohort of children diagnosed with Specific Language Impairment and showing syntactic deficits were tested for their ability to subitize. The results for the group as a whole were inconclusive, but one of the subjects showed marked difficulties with both the syntactic and subitizing tasks. We conclude that while further experiments are needed with a larger subject pool, the initial results may support a neural (and therefore evolutionary) link between the processing of argument structure and the ability to subitize.