Table 1.
Sample stimuli used in the fMRI experiment.
| Possessive Construction Task (PCT) |
| What my father is is a doctor. |
|
| Working Memory Task (WMT) |
|
PT; Pointing Sign.
Japanese Sign language (JSL) has the basic word or constituent order of SOV (subject-object-verb), but exhibits free word order as spoken Japanese does. There are, however, some restrictions on constituent order. Consider “/PT-I/ /FATHER/ /OCCUPATION/ /WHAT/ /DOCTOR/,” which means “What my father is is a doctor.” In JSL, possessives cannot be moved from their modifying head nouns, whose phenomenon in spoken languages has been discussed in terms of the Left Branch Condition since Ross (1967). For example, possessive pronoun MY indicated by /PT-I/ cannot be separated from FATHER as in “/FATHER/ /OCCUPATION/ /PT-I/ /WHAT/ /DOCTOR/,” which is ungrammatical. In the Possessive Construction Task (PCT), where the participants were visually presented with both possible and impossible JSL in random order on a screen, they had to judge the grammaticality of the JSL by pressing a button. In the Working Memory Task (WMT), the participants were instructed to determine whether the sequence just presented included three different signs. A stimulus with different three signs was treated as a “grammatical JSL” stimulus, whereas a stimulus including two identical signs was regarded as an “ungrammatical JSL” sequence.