This paper investigates, with the help of computer-vision technology,the similarities and differences in the rhythm of themovements of the head in sentences in Finnish (FinSL) andSwedish Sign Language (SSL). The results show that themovement of the head in the two languages is often very similar:in both languages, the instances when the movement of thehead changes direction were distributed similarly with regardto clause-boundaries, and the contours of the roll (tilting-like)motion of the head during the sentences were similar. Concerningdifferences, direction changes were found to be usedmore effectively in the marking of clause-boundaries in FinSL,and in SSL the head moved nearly twice as fast as in FinSL. However, the small amount of data means that the results canbe considered to be only preliminary. The paper indicates theroll angle of the head as a domain for further work on head related rhythm.

In this paper we examine the relationship between specifichead movement events – head nods, often treated as prosodicboundary markers – and syntactic units in Finnish (FinSL) andSwedish Sign Language (SSL). In the study we investigatedthe alignment of head nods with syntactic units on the basis ofa total of 20 (10+10) FinSL and SSL narratives. The results ofthe study show that in both languages head nods appeared similarlyon syntactic boundaries and that the tendency was toalign nods sentence-finally. However, not all head nods behavedthis way: for example, a relatively large number of headnods were also found to occur sentence-initially or elsewherein the sentence. Furthermore, head nods occurring on syntacticboundaries also had non-boundary marking functions, and notall syntactic boundaries occurred with head nods.