The definition of the TOPIC within Language into Act Theory and its identification in spontaneous speech corpora

The paper presents the definition of the TOPIC information unit within the Language into Act Theory (L-AcT) and the prosodic and informational criteria used for its recovery in spontaneous speech corpora: Italian, Brazilian Portuguese, Spanish and American English. The TOPIC develops the specific function of field of application of the illocutionary force accomplished by the COMMENT unit, it is performed through a prefix prosodic unit and precedes the Comment. The TOPIC must be coherent with the set of requirements determined by the illocutionary force of the Comment and adequate to the speaker-addressee relation. TOPIC mostly correlates in spoken corpora with NP and ADVP and must be functionally distinguished from “postponed Topic” (APPENDIX in the L-ACT framework). However, corpora also show a good percentage of modal expressions filling its prosodic and distributional conditions.