Which of the following statements about synaptic connections are correct? A.…

Concept

Early neural development produces more synaptic connections than the mature nervous system retains. Experience-dependent stabilization strengthens frequently active pathways, while synaptic pruning removes or reorganizes connections that are not effectively used.

Thus, neural development combines synaptic overproduction with selective retention and pruning; ordinary use does not weaken or destroy a connection.

Application

Statement B describes synaptic overproduction: approximately twice as many connections may initially be formed as are ultimately used. Statement C describes pruning or reorganization: unused connections disappear or are replaced by other pathways. Statements A and D reverse the effect of use, because active connections are generally stabilized rather than weakened or made to perish.

Contrast

• A, B and D only includes both unsupported claims about used connections.

• B and C only combines the two supported developmental processes: overproduction and pruning or reorganization.

• A and D only consists solely of claims that active connections weaken or perish.

• B, C and D only adds the unsupported claim that an active connection perishes.

Cross-check

The standard use-dependent rule predicts selective survival of active pathways and removal of inactive ones. Under that rule, B and C are consistent together, whereas A and D are not. Therefore, the correct answer is B and C only.