What describes the increased efficiency of signal transmission at synapses as a result of repeated trials?

The concept of increased efficiency of signal transmission at synapses due to repeated trials is best captured by long-term potentiation (LTP). LTP is a lasting enhancement in the strength of synaptic transmission that occurs when the synapse is stimulated repeatedly over a period of time. This process is thought to underlie several forms of learning and memory, as it reflects changes in the synaptic strength that facilitate communication between neurons.

In the context of learning, when certain synaptic pathways are activated frequently, the efficiency of neurotransmitter release and the sensitivity of the postsynaptic receptors can increase. As a result, the same amount of stimulation leads to a comparatively stronger signal, which is foundational for forming memories and reinforcing learning.

Additionally, long-term potentiation is often associated with structural changes in the brain, such as the growth of new synaptic connections, further solidifying the learned information. This contrast with other options, which may describe aspects of synaptic function or neural change, yet do not specifically capture the sustained enhancement in synaptic strength over time that is characteristic of long-term potentiation.