“…Researchers are increasingly asking to what extent the principles of L2 acquisition apply when the source language is spoken and the target language is signed (Chen Pichler and Koulidobrova, 2016 ). While many challenges are similar for hearing learners of signed and spoken second languages, additional issues arise when acquiring a new language in a new modality (McKee and McKee, 1992 ; Wilcox and Wilcox, 1997 ), including learning to manage visual-manual phonology (Bochner et al, 2011 ; Chen Pichler, 2011 ; Ortega, 2013 ; Ortega and Ozyurek, 2013 ; Ortega and Morgan, 2015 ), multiple articulators (Gulamani et al, 2020 ), spatial grammar and depicting referents with the body (Bel et al, 2014 ; Ferrara and Nilsson, 2017 ; Frederiksen and Mayberry, 2019 ; Kurz et al, 2019 ; Gulamani et al, 2020 ), using the face to display grammatical information (McIntire and Reilly, 1988 ), and the high degree of iconicity in sign languages (Lieberth and Gamble, 1991 ; Campbell et al, 1992 ; Baus et al, 2013 ; Ortega and Morgan, 2015 ). At the same time, it is possible that hearing learners' experience with co-speech gesture in their L1 affects their acquisition of a sign language (McIntire and Reilly, 1988 ; Taub et al, 2008 ; Chen Pichler and Koulidobrova, 2016 ).…”