René Descartes introduced the notion of the:

The __________ threshold is the smallest amount of energy needed for a person to detect the presence of a stimulus 50% of the time

a. absolute b. difference c. just noticeable d. sensory

If Ivan Pavlov rang a bell while putting a bowl of food on the floor in front of his dogs, this would be an example of __________ conditioning

a. delayed b. trace c. simultaneous d. latent