Early Speech Production in Infants and Toddlers Later Diagnosed with Cerebral Palsy: A Retrospective Study (2022)

Abstract: In this retrospective study, we compared the early speech development between infants with cerebral palsy (CP) and typically developing (TD) infants. The recordings of utterances were collected from two CP infants and two typically-developing (TD) infants at approximately 8 and 24 months old. The data was analyzed by volubility, consonant emergence, canonical babbling ratio (CBR), mean babbling level (MBL). The major findings show that comparing with TD group, CP group has the characteristics of: 1) lower volubility 2) CBRutter below 0.15 at 2 years old 3) MBL score below 2 at the age of 2 with a feature of above 95% in level 1 4) using consonants mainly at two oral places (bilabials and velars) and three manners of articulation (nasal, fricative, and stop) at 2 years old.

## introduction cerebral palsy (cp) is a non-progressive and permanent motor disorder, caused by the impairment of neurodevelopment in the fetal or infant brain @xcite . more than 60% of children with cp has communication problems stemming from the language or/and speech impairments, including delayed language development, voice disorders, and speech disorder @xcite .these abnormality in speech may adversely affect the following ability in terms of communication, intelligibility, phonological awareness and literacy @xcite . for children with cp, these difficulties may eventually result in the poor performance in academy, problems in relationship, and also less career opportunities. as a result, many researches have suggested early intervention not only aim to diminish the negative impact of the limited motor functions but also provide mental health support for the caregivers @xcite . previous studies have widely documented similar transition in developing stages for infants' vocalization in the first and second year of life and showed the strong relation to the future language ability(d' @xcite . however, rare speech development related studies included data with cp infants under 2 years old. studying early infants' vocalization has helped enriched our knowledge about disorders, such as hearing impairment, down syndrome, fragile x syndrome @xcite , autism @xcite , and cas (m. overby & caspari, 2015; m. s. @xcite , reducing the severity and providing evident-based support for clinical decision. volubility, consonant inventory, and the development of canonical babbling are three widely studied domain in early infant speech production, and many has shown to be a precursor to later language ability @xcite . @xcite measured the speech and language development of 27 children at the age between 24 and 30 months, finding that three groups of children with cp with different level of language ability (i.e., not talking, emerging talking, and established talking) can be identified at the age of 2. speech and/or language delay was found in two groups of children (nearly 85% of the children in this study) and also suggested speech and language assessment and intervention before 2 years old. since obvious differences appeared at the age of 2, more data is required to clarify the details of the progression in speech development. therefore, the goal of this study is to investigate the speech development of 2 cp and 2 td infants and try to answer the following questions: table1. data recordings all recordings were taken at either hospital or home under the natural interaction with caregivers and/or an experimenter. for each infant, one recording is included by the age around 1 year and 2 years old. each recording session lasted for around 35 to 60 minutes. a shure wireless mini microphone was clipped to the cloth near infants' mouth and connected to a tascam recorder. ## result and discussion in this study, we investigate volubility, consonant emergence, canonical babbling in order to enrich the knowledge about early speech production in cp infants. the results are also considered as several possible warning signs for cp infants who may have language and/or speech problems in the future. ## conclusion findings in this investigation imply the speech development differences between td infants and cp infants at the age between 8 to 24 months old. although it is a preliminary study, the below possible warning sign might be clinical warning sign that could help the identification of infants and toddlers at risk for later diagnosis of speech and language problem in children with cp: (1) low volubility (2) cbr @xmath0.15 at 2 years old (3) mbl @xmath1, fricative, and stop) at most at 2 years old. more data and studies are required for clarifying the changing course between 1 and 2 years old. more amounts of subjects are also suggested to be included in future studies.