Manual babbling

Manual babbling is a linguistic phenomenon that has been observed in deaf children and hearing children born to deaf parents who have been exposed to sign language. Manual babbles are characterized by repetitive movements that are confined to a limited area in front of the body similar to the sign-phonetic space used in sign languages. In their 1991 paper, Pettito and Marentette concluded that between 40% and 70% of deaf children's manual activity can be classified as manual babbling, whereas manual babbling accounts for less than 10% of hearing children’s manual activity. Manual Babbling appears in both deaf and hearing children learning American Sign Language from 6 to 14 months old (Marschark, 2003). Manual babbling is not to be confused with movement that is motor-driven and non-communicative/common communicative in nature. Babbling occurs during the same period of development when an infant is also trying to establish a sense of their spatial orientation and cognition. This results in arm and hand movements outside of what could be categorized as manual babbling. For example, when an infant waves their arm back and forth, they may be transitioning between uncoordinated behaviors and intentional, voluntary behaviors like reaching. The frequency of these arm and hand gestures peaks between 5 and a half months and 9 and a half months, which is around the same time that babbling begins (6 to 9 months). Babbling is an important step in the language acquisition of infants (Chamberlain et al, 1998). Before an infant is even able to form their first words, they will produce these phonological tokens that, while meaningless, conform to the broad rules for syllable structure. Children that have access to spoken language will produce vocal babbles while children that have access to signed language will produce manual babbles. In other words, “vocal babbling is “triggered” by the patterned input of a spoken linguistic environment while manual babbling is triggered by the patterned input of a signed linguistic environment” (Cormier et al.