Activation and search instructions

Table 3.1. Topic continuity hierarchy Most continuousaccessible least surprising zero anaphor unstressedclitic pronouns stressedindependent pronouns unmodified definite NPs restrictively modified definite NPs referential indefinite NPs Least continuousaccessible most surprising If this is combined with Gernsbacher 1989, 1990 and Chang’s 1980 work, a likely pattern emerges. Zero pronouns show little ability to enhance activation of the referent or suppress activation of a nonreferent Corbett and Chang 1983. Pronouns do not increase the activation of their referent, but do suppress the activation of nonreferents by the end of the sentence. Names immediately increase the activation of their referent and suppress the activation of all other participants Gernsbacher 1990. Just looking at Gernsbacher’s activation data we can conclude that speakers can vary the level of activation of participants by the choice of referential forms. His data consisted primarily of isolated sentences with little or no discourse context. It is unclear at this stage what effect a surrounding con- text would have on actual activation levels, but it is clear that the choice of form resulted in a change of activation. By sentence end a participant which was referred to by name had the highest level of ac- tivation. If the participant was referred to only by a pronoun it will have the second highest activation level. When one participant is referenced by a pronoun any participant who was not referenced will have a lower activation level than the participant which was referenced. Finally, when a participant was referenced by a name, any participant which was not referenced is strongly suppressed, giving them the lowest activation. This is summarized in table 3.2. Table 3.2. Effects on activation of participants by different referential devices Referential device Effect on the referenced participant Effect on all other participants name maximum enhancement maximum suppression common noun medium enhancement medium suppression pronoun little enhancement medium and slower suppression zero no enhancement little suppression

3.4.3 Activation and search instructions

Controlling the activation levels of different participants allows the speaker to give them different levels of importance. By the choice of form the speaker effects the activation level in the mind of the comprehender. From Gernsbacher’s work we see that the changes in activation levels are the direct re- sult of the use of different referential forms. These levels of importance can be varied throughout a dis- course. Givón has theorized about the use of different referential devices as “mental processing instructions” Givón 1990:914. In this view he includes both a search strategy and setting up a the- matic paragraph topic as objectives of these instructions. Any search instructions are for immediate use, but the setting up of thematic paragraphs or characters is a strategy for following material. If a participant can be referenced in such a way as to become “prominent enough” it will replace the cur- rent active paragraph topic. Essentially Givón is setting up a binary system in which one item is active in a given clause. This is an oversimplification of what we know. From reaction time studies, it is known that items are not turned on and off like a switch, but rather activation levels move up and down. Gernsbacher has never claimed that the use of a name deactivated the unnamed referent, but that the activation of that referent was suppressed. Rather than a switch metaphor we would be much 58 The Rationale for Different Referential Forms better thinking of a light dimmer or multiple dimmers. Activating one concept does not automatically turn off all others. It may turn them down. Furthermore using a pronoun does not turn up the activa- tion of the referent, it turns down the others. Just as a lighting designer can control the amount of light each actor on a stage gets and so suggest the amount of attention to be paid to any given actor, a lan- guage producer by using different referential devices can suggest the amount of attention to be paid to any individual participant. And much as the lighting designer has to work within the current limitations of his equipment, so too the language comprehender does not have an unlimited amount of mental processing power to devote to all the different participants.

3.5 Goal Oriented Activation