Inclusion Criteria:

   - Diagnosis of Autism Spectrum Spectrum Disorder (ASD) based on clinical interview and
   Diagnostic and Statistical Manual, 5th edition (DSM-5) and confirmed using the Autism
   Diagnostic Interview Revised (ADI-R) and the Autism Diagnostic Observation Schedule
   (ADOS) and/or Brief Observation of Symptoms of Autism (BOSA) and/or Childhood Autism
   Rating Scale- Second Edition (CARS-2).

   - Outpatients between 2.0 and 4.11 years of age of either gender,

   - Children of all cognitive levels will be included as long as they are able to
   participate in the testing procedures to the extent that valid standard scores can be
   obtained

   - Language delay as measured by the Preschool Language Scale, 5th Edition (PLS-5) [at
   least 1 standard deviation behind for children age 2 and 3 years; and 2 standard
   deviations behind for children age 4],

   - Stable psychotropic medication(s) or biomedical intervention(s) for at least 1 month
   prior to baseline measurements with no anticipated changes during study participation,

   - Stable treatment [Applied Behavior Analysis (ABA), Floortime, or other interventions],
   speech therapy, and school placement for at least 1 month prior to baseline
   measurements with no expected changes during study participation,

   - No more than 60 minutes of 1:1 speech therapy per week,

   - The child's exposure to the English language must be sufficient that administration of
   standardized tests in English is appropriate for measuring progress,

   - The availability of at least one parent who can consistently participate in the
   training sessions and related activities, and

   - Successful completion of baseline brain scan.

Exclusion Criteria:

   - Current or life-time diagnosis of severe psychiatric disorder (e.g., bipolar
   disorder),

   - Genetic abnormality (e.g., Fragile X)

   - Presence of active medical problem (e.g., unstable seizure disorder),

   - Receiving more than 15 hours of in home 1:1 Applied Behavior Analysis (ABA) per week

   - Magnetic Resonance (MR) contraindication (e.g., the presence of ferrous metal), or

   - Previous adequate Pivotal Response Treatment (PRT) trial.