This graph shows population projections for the United States of America. The estimated population of the USA in 2050 is 398 million residents.
Down Syndrome â Speech Therapy for Children with Down syndrome have strengths and challenges in development of communication skills, including receptive (understanding) language and expressive (speaking and composing sentences) language skills and reading.
Knowledge center. Down syndrome (or Down's syndrome) is a chromosomal disorder caused by an error in cell division that results in an extra 21st chromosome. The condition leads to impairments in both cognitive ability and physical growth that range from mild to moderate developmental disabilities.