We report data from 28 infants with NF1 tested longitudinally at 5, 10 and 14 months compared to cohorts of 29 typical likelihood infants (with no history of NF1 or ASD and/or ADHD), and 123 infants with a family history of ASD and/or ADHD. Here, NF1 is linked to neurofibromatosis type 1.