Effects of Feedback Availability Upon Generation of Left- and Right-Branching Sentence Structures

It was reasoned that the capacity of short-term memory places limitations upon the syntactic structures produced by the human speaker, but that such limitations would be compensated for if the encoder had a continuous record (feedback) of his production during the creation of a sentence. Accordingly, this experiment involved having subjects create left-branching and right-branching sentence patterns (the former presumed to impose more demands upon short-term memory than the latter) under typewriting conditions where feedback was either available or was denied. Results indicated that although left-branching took relatively more processing time than right-branching, the anticipated interaction with feedback conditions was not realized. Moreover, in terms of error-rate, it was found that right-branching, rather than the predicted left-branching, was facilitated by the presence of feedback.