Mechanisms underlying the development of autism: a multi-site prospective study in very young high-risk siblings and controls

Recruitment & Eligibility

Status: Completed

Sex: Not specified

Target Recruitment: 105

Inclusion Criteria

High-risk siblings:
- Age between 4 months and 6 months OR younger than 11 months
- Older full sibling with ASD (clinical diagnosis autism, PDD-NOS or Asperger syndrome)
- At least one parent speaks Dutch to child at home (does not need to be parent*s native language);Controls:
- Age between 4 months and 6 months OR younger than 11 months
- Older full sibling with typical development (by parent report)
- At least one parent speaks Dutch to child at home (does not need to be parent*s native language)

Exclusion Criteria

High-risk siblings:
- Diagnosis of epilepsy or history of fits/convulsions
- Presence of genetic syndrome (in proband or infant) clearly related to ASD (e.g. Tuberous Sclerosis, Fragile-X)
- Presence of known significant uncorrected vision or hearing impairment in infant (reported to parent by a doctor or health professional)
- Infant was premature (pre 36 weeks)
- Infant is looked after by the state (e.g. foster care), or other situation in which neither birth parent is involved in the infant*s care.
- Presence of known significant developmental or medical condition in infant likely to affect brain development or infant*s ability to participate in the study (e.g. Cerebral Palsy, Down*s syndrome, cystic fibrosis, foetal alcohol syndrome);Low-risk:
- Diagnosis of epilepsy or history of fits/convulsions
- Presence of known significant uncorrected vision or hearing impairment in infant (reported to parent by a doctor or health professional)
- Infant was premature (pre 36 weeks)
- Infant is looked after by the state (e.g. foster care), or other situation in which neither birth parent is involved in the infant*s care.
- Presence of known significant developmental or medical condition in infant likely to affect brain development or infant*s ability to participate in the study (e.g. Cerebral Palsy, Down*s syndrome, cystic fibrosis)
- Interested in study because parents are concerned that their infant is developing ASD, despite negative family loadings
- Presence of ASD in 1st degree relatives

Study & Design

Study Type: Observational non invasive

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>The main dependent measure is the diagnosis of ASD and the severity of ASD<br /><br>symptoms at age 36 months.<br /><br><br /><br>The main predictive measures for cognition, eye tracking and EEG/ERP are:<br /><br>- Cognitive functioning (Mullen Scales of Early Learning)<br /><br>- Time locked voltage changes (µV) at different electrode sites (EEG)<br /><br>- Amplitude of event-related potentials wave to stimuli (ERPs)<br /><br>- Evaluation of EEG power spectrum (frequency and time frequency analysis) (EEG)<br /><br>- Power changes (µV2) at different electrode sites (EEG)<br /><br>- Oxygenated and deoxygenated hemoglobin concentration changes (NIRS)<br /><br>- Location of eye gaze and timing of eye movements (eye tracking)<br /><br>- Anticipatory eye movements (eye tracking)<br /><br>- Fixation duration (eye tracking)</p><br>

Secondary Outcome Measures