Is a deficiency in synaptic pruning part of the explanation for autism?
That’s the question raised by recent research published online in the journal Neuron. The study, carried out by scientists at Columbia University, USA compared the brains of children and young people with autism with the brains of similarly aged non-autistic subjects.
Typically, as a child’s brain matures the density of neurons and synapses is reduced through a process known as pruning. But the study found that this process was typically reduced by two-thirds in the case of those diagnosed with autism.
By late childhood spine density had dropped by about half in the control brains, but by only 16% in the brains of autism patients. The researchers have traced the pruning defect to a protein called mTOR.