The distribution of pitch accents in instructions as a function of discourse structure

Speakers gave instructions to listeners to assemble the front view of a house from a set of ready-made parts. The main aim was to find out how the distribution of accents over expressions referring to the parts of the front view was related to the structure of the monologues containing the instructions. Each monologue was analysed as a series of instructions, each instruction specifying to the listener what to do with one part of the front view (the TOPIC of the instruction). It turned out that the instruction was a meaningful unit of analysis: when topics were introduced into an instruction, the speaker always used accented expressions; afterwards the topic was often referred to by a pronoun. When the speaker mentioned other parts of the front view in the course of an instruction, he mostly used the names of the parts; most of these names were accented, though more often when they were used for the first time in an instruction than when they were used later on. The results were interpreted to mean that the speakers used accentuation to signal to the listener the degree of availability of the information conveyed: an accented expression signals to the listener that he cannot easily map the expression onto the information it refers to in the context; an unaccented expression signals to the listener that he can map the expression directly onto the intended information, since the information at that point in the utterance may be supposed to be maximally activated due to the preceding context. Some consequences were considered for the listener's processing of the incoming information