Each day, a lab assistant in a white coat takes a rat out of its home cage and brings it to another room to give it a shot of morphine. The rat is then tested to see how well the morphine is blocking its pain (by seeing how much heat can be applied to its tail before the rat moves it away). The amount of morphine is the same every day, but the amount of pain blocked is less and less as the rat develops tolerance to the drug. After doing this for two weeks, the rat is unexpectedly given the shot of morphine in its home cage by a different assistant. According to the CCR, what should we expect about how much pain the dose of morphine will block this time?
The morphine will be even LESS effective because the animal was not prepared for it.
The morphine will be just as effective as if they gave it in the usual way. Because the rat had developed tolerance, the pain blocking would be as low as it was the day before.
The morphine will work BETTER than it did the day before with the rat showing less tolerance to the drug.
In this case, the MORPHINE is a
UCS
UCR
CS
CR
The lab assistant, other lab room, feeling the needle stick, being removed from the home cage, etc., are all
UCS's
CS's
UCR's
CR's
Showing TOLERANCE to the morphine is an example of a
UCS
UCR
CS
CR
In another experiment, the rat is given the same dose of morphine each day, just as described in the previous study. On the last day, however, the rat is removed from the home cage by the same lab assistant and everything is done exactly the same EXCEPT, the shot has only a placebo (normal saline water) and NO MORPHINE. How much pain will the rat put up with this time?
It will put up with LESS pain. It will be more sensitive to the heat than it was before the first time morphine was given.
It will put up with the SAME as the previous day. Because it was expecting a drug, the body will act like the drug was there.
It will put up with MORE pain. Because there is no actual drug to compensate for, the rat will show more pain tolerance.
In one final experiment, the assistant gives more and more morphine in order to counteract the tolerance to the drug the rat is developing. In this way, the rat shows the same ability to put up with the pain each day, but ends up taking more drug so that can happen. On the last test day, they again sneak the drug to the rat in its home cage without any of the normal cues. The amount of drug given is the same as it received the previous day. What happened?
The rat put up with slightly less pain than the day before because its body continued to develop tolerance to the drug.
The rat put up with the same amount of pain as the day before because that was the last level learned.
The rat overdosed and died because it was not prepared for the larger dose of morphine.
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