Syntactic errors in speech

Speech errors can be used to examine the nature of syntactic processing in speech production. Using such evidence, Fay (1980a, 1980b) maintains that deep structure and transformations are psychologically real. However, an interactive activation model that generates surface syntactic structures directly can account for all the data. Most syntactic errors are substitutions: The target phrase structure is replaced by a semantically related structure. Blends of two syntactic structures are also common. Transformations cannot account for much of the data and are not necessary to explain any of them. While it is impossible to prove that transformations do not exist, syntactic theories that do not include transformations have the potential to be psychologically valid.