Speech-in-noise Perception in Autism and Fragile X

Inclusion Criteria: 1. normal audiograms (PTA ≤ 20 dB HL) 2. corrected 20/20 vision (Snellen chart) 3. no history of premature birth (prior to 36 weeks gestation) 4. no medications known to affect EEG signal 5. English as the first language Inclusion for the Autism group requires the following: 1\) diagnosis of Autism Spectrum Disorder either based on previous ADOS administration and developmental history, or confirmed via ADOS and developmental history Inclusion for the Autism + FXS group requires the following: 1. Documented PCR/Southern Blot genetic testing confirming full mutation FXS 2. Diagnosis of Autism Spectrum Disorder, per Autism group. Inclusion for the Typically Developing group requires the following: 1. no siblings or parents with an Autism Spectrum Disorder or Fragile X Syndrome 2. no current neurological or psychiatric diagnoses 3. IQ over 75 Exclusion Criteria: * Hearing loss or uncorrected vision loss * history of premature birth (prior to 36 weeks gestation)