3. Spectrum of Impairments
Children with autism are often somewhat delayed in motor development,
and neurological "soft signs" like poor manual dexterity remain. This can
be compared to the "minimal" impairment observed in monkeys
subjected to asphyxia at birth.
The long tradition of waiting for the first breath has been replaced by a
protocol to clamp the umbilical cord immediately at birth. This may cause
a brief period of asphyxia in infants who are slow to begin breathing.
1 - Autism, a neurologic disorder?
6 - Obstetric procedures
5 - The broader autism phenotype (BAP)
4 - Autism versus cerebral palsy
3 - Hemoglobin
2 - Metabolic activity in the brain
The brainstem nuclei damaged by asphyxia at birth are metabolically the
most active centers of the brain, and their function may be to maintain
environmental awareness.
Hemoglobin delivers oxygen to tissues in exchange for carbon dioxide.
The brainstem nuclei of high metabolic rate are thus spared during a
period of partial oxygen insufficiency, at the expense of the less active
cerebral cortex.
Damage of the cerebral cortex, characteristic of cerebral palsy, was
experimentally produced in monkeys by prolonged partial hypoxia.
Motor clumsiness in children with Asperger syndrome may reflect a
combination of partial hypoxia plus a brief period of total asphyxia at birth.