3.1.3. Movement reduction and extension
In some cases, LIS signs can undergo movement modification. Specifically, in the modified form, the movement component can be either reduced or extended, thus consisting in smaller or larger movements with respect to the citation form.
Movement modification can be motivated by several linguistic as well as extra-linguistic factors. Morphological processes, such as pluralisation (MORPHOLOGY 4.1) and deverbalisation (MORPHOLOGY 2.1.2.1), might have an impact on the movement component. Movement reduction may be motivated by a drive toward articulatory ease and effort reduction. On the other hand, external factors that may cause reduced movements are space limitations (e.g. video chatting) or situational restrictions on intended audience (i.e. whispering mode). Instead, movement extension may be motivated by emotions such as excitement and anger (i.e. shouting mode), emphasis, or special registers (e.g. child-directed signing).
Generally speaking, movement can involve different articulatory joints: the shoulder, the elbow, the radioulnar, the wrist, the base joint (the knuckles which connect the digits to the hand) and the interphalangeal joints (the knuckles at the midfinger). It is important to distinguish two different types of movement modification: i) reduction or extension occurring at the same joint where movement is produced in the citation form and ii) reduction or extension occurring at a different joint. These two categories are described in detail in the next sections.
