Hypotéza vymazávání stop a její platnost v češtině u pacientů s Brocovou afázií

This paper presents and discusses the results of an experiment testing the validity of the Trace Deletion Hypothesis (Grodzinsky 1989, 2000) in Czech. The Trace Deletion Hypothesis (= TDH) was proposed to account for a receptive syntactic deficit in Broca’s aphasics that involves structures containing transformational operations such as the passive. According to the assumptions of the TDH, in passive constructions Broca’s aphasics fail to assign a semantic θ-role to the derived subject syntactically, so they assign it the Agent θ-role by linear consideration (Default Principle), which results in a structure with two potential Agents. This strategy is supposed to lead to the chance performance of Broca’s aphasics in these structures, as they are forced to guess the distribution of the Agent and the Patient θ-roles. The results of our experiment, however, do not support the TDH-proposal: out of the six tested subjects, only one performed at chance. The error rate for reversible passive structures in Czech was 33.34%, which corresponds to an above-chance performance. Given these results, the validity of the TDH is called into question, also with respect to the development of the generative theory itself.