Cognitive and Sensorimotor Mechanisms of Autism Spectrum Disorder (ASD)
220 individuals with aSD, 200 age-matched healthy controls between 2-55 years, and 20 parents or caregivers of an individual with aSD will participate in these studies at the uT Southwestern Medical Center at Dallas. in addition, we aim to enroll both biological parents as well as biological siblings of each individual with aSD when possible. individuals with aSD will still be included even if one or both biological parents are not available to participate. We estimate that between 200-400 biological parents (1 to 2 per child) and 100 biological siblings will complete the cognitive, neuropsychological, eye movement and manual motor testing in addition to the blood draw and clinical report measures. additionally, we will recruit 50 participants diagnosised with Fragile X Syndrome. Twenty of the individuals with aSD and 20 parents/caregivers will participate in a training protocol at uT Southwestern Medical Center at Dallas that will focus on teaching members of the assessment team to use the diagnostic assessments. individuals participating in the training sessions will not complete the rest of the study protocol. Recruitment and enrollment has ceased at the university of illinois at Chicago. We will study a large number of affected individuals so that we may perform developmental studies and comparisons between distinct phenotypes associated with aSD (e.g., affected individuals with and without language delays). a smaller subset of these individuals will be able to complete eeG and MRi testing; eligibility for these portions of the study will be determined based on age (in our experience, individuals younger than age 7 years will not be able to complete an MRi scan) and individual subject characteristics. if an individual appears to be unable to remain still long enough to complete the MRi or eeG testing, then he/she will not be scheduled for these study sessions and this decision with the participating family (if individual is a minor) or subject.
Primary analyses will compare individuals with aSD and/or Fragile X and healthy controls on higher-order and sensorimotor repetitive behaviors, executive control, motor accuracy, motor speed, and motor skill acquisition. additional comparisons of resting state eeG activity and BoLD responses during fMRi testing of executive and sensorimotor processes also will be performed. Participants will be evaluated during one to five study sessions that will be scheduled based on subject availability.
ASD Participants: Male and female participants with ASD must be aged between 2 to 55 years. The lower age limit was chosen to include only individuals with ASD who can complete the measures, and two years of age is the earliest age at which a reliable diagnosis of ASD currently can be verified. Additionally, subjects must meet the following conditions:
1) Be capable of understanding and cooperating with testing;
2) Be free of seizure disorder unless there is an identifiable genetic cause for their ASD;
3) Be in good medical health;
4) Meet DSM-IV criteria (American Psychiatric Association) for ASD (Autistic Disorder, Asperger[Single Quote]s Syndrome, Pervasive Developmental Disorder-NOS) on the basis of the ADOS, ADI, and consensus diagnosis.
Fragile X Participants. We propose to recruit 50 participant with Fragile X Syndrome. Participants will be recruited through the same methods described above for ASD participants.; Patients with Fragile X syndrome will be included regardless of their ASD status, but we will perform testing to confirm their Fragile X status. Fragile X patients do not have to have a diagnosis for ASD, but will need a diagnosis of Fragile X.
Healthy Control Subjects. Healthy community controls stratified to match the ASD group on age, IQ, and sex ratio. All healthy controls must be between the ages of 2x 55 years old. Subjects will be recruited if they:
1) Do not meet DSM-IV criteria for any significant lifetime psychiatric or development disorder, and
2) Have no family history of ASD in their first degree relatives according to our family history screening.
Healthy controls must have also a history of regular school attendance and grades consistent with ability level and have Full Scale IQ score of 70 or higher.
Biological Parent Subjects: Parents will complete the SCQ to screen for ASD. Parents with SCQ scores greater than 15 will be evaluated for a possible diagnosis of ASD using the ADOS, and will be included in the study regardless of the outcome of this evaluation to have a representative sample of parents. Biological parents must be 55 years of age or under and have Full-Scale IQs of 70 and higher in order to participate in neuropsychological, sensorimotor, and cognitive testing, as well as brain imaging. Biological parents above the age of 55, but with Full-scale IQs of 70 or higher, will only complete the blood draw and clinical report measures.
Biological Siblings: Biological siblings must be between the ages of 2 and 55 years and have Full-Scale IQs of 70 and higher in order to participate in neuropsychological, sensorimotor, and cognitive testing, as well as brain imaging. Biological siblings above the age of 55, but with Full-scale IQs of 70 or higher, will only complete the blood draw and clinical report measures.