Final answer:
Presynaptic inhibition reduces neurotransmitter release from the presynaptic neuron, affecting the behavior of the cell. During habituation in an Aplysia sensory neuron, there are changes in the synaptic connections that result in a decreased behavioral response.
Step-by-step explanation:
Presynaptic inhibition refers to the reduction in the release of neurotransmitters from the presynaptic neuron, resulting in decreased excitatory or inhibitory effects on the postsynaptic neuron. In this case, the behavior of the presynaptic cell is altered by reducing the synaptic transmission.
In an Aplysia sensory neuron during habituation, there are changes in the wiring of the neural circuit involved in the response. With repeated exposure to a non-harmful stimulus, the sensory neuron becomes less responsive, leading to a decrease in the strength and duration of its synaptic connections with other neurons involved in the response. This decrease in synaptic strength is thought to underlie the decreased behavioral response observed during habituation.