Final answer:
To determine a change in synaptic strength, one would measure post-synaptic potentials via electrophysiological recordings. Changes in PSP amplitude or frequency can indicate long-term potentiation or depression. Observing neurotransmitter release and ion flow changes is also key to assessing synaptic transmission.
Step-by-step explanation:
To experimentally determine a change in synaptic strength, one could measure the amplitude or frequency of the post-synaptic potentials (PSPs) using techniques such as patch-clamping or microelectrode recordings. An increase in the amplitude or frequency of PSPs generally indicates long-term potentiation (LTP), which is a strengthening of synaptic transmission, while a decrease indicates long-term depression (LTD). During the experiment, you would apply stimuli of consistent intensity to the presynaptic neuron and record the resulting PSPs in the postsynaptic neuron. Changes in synaptic strength can be inferred from the changes in these recordings over time, particularly before and after a protocol designed to induce LTP or LTD, such as high-frequency stimulation for LTP or low-frequency stimulation for LTD.
Moreover, you could investigate the synaptic transmission process by measuring neurotransmitter release and receptor binding, and their subsequent effects on ion flow across the synaptic cleft. Utilizing fluorescent indicators and imaging techniques could provide a visual and quantitative method to observe these changes.