Which statement best links pruning to neurodevelopmental disorders?

Which statement best links pruning to neurodevelopmental disorders?

• A. Under-pruning leads to excess synapses associated with autism; over-pruning leads to fewer synapses associated with schizophrenia
• B. Under-pruning leads to fewer synapses; over-pruning leads to more synapses
• C. Pruning has no relation to autism or schizophrenia
• D. Pruning only affects myelination

Answer: (A)

Synaptic pruning is the process of removing excess synapses during brain development to refine neural networks. When pruning is reduced, you end up with too many synapses, a pattern that has been linked to autism spectrum disorders and atypical connectivity. When pruning is excessive, too many synapses are eliminated, which can lead to reduced connectivity and the neural changes seen in schizophrenia, especially during adolescence. So, the idea that under-pruning results in excess synapses linked to autism and over-pruning results in fewer synapses linked to schizophrenia best fits what we understand about these disorders. The other statements don’t fit because pruning directly affects synaptic density (not just myelination), and there is evidence connecting pruning abnormalities to both autism and schizophrenia rather than none.

Synaptic pruning is the process of removing excess synapses during brain development to refine neural networks. When pruning is reduced, you end up with too many synapses, a pattern that has been linked to autism spectrum disorders and atypical connectivity. When pruning is excessive, too many synapses are eliminated, which can lead to reduced connectivity and the neural changes seen in schizophrenia, especially during adolescence. So, the idea that under-pruning results in excess synapses linked to autism and over-pruning results in fewer synapses linked to schizophrenia best fits what we understand about these disorders. The other statements don’t fit because pruning directly affects synaptic density (not just myelination), and there is evidence connecting pruning abnormalities to both autism and schizophrenia rather than none.