Morkeliph
01-30-2006, 5:07 PM
While reviewing a chapter in my old psychology text book I came across something that I thought was very interesting about drug tolerance.
Several studies have shown that drug tolerance may be in large part classically conditioned. It is a well established fact that drug abusers and medicinal patients developed tolerances to drug effects. That is why drug abusers often have to increase their dosage to achieve the same effect, resulting in a more spendy habit that causes many to resort to other crime, like theft. What is interesting is that these tolerances have been shown to often be environmentally specific. What is so interesting about that you ask? First let me explain what I mean by environmentally specific.
Those familiar with classical (respondent or Pavlovian) conditioning already know that when a neutral stimulus is paired in presentation with an unconditioned stimulus (US) that the neutral stimulus comes to elicit a response similar to that of the US. Pavlov's dogs are the classic example. After Pavlov repeatedly paired a bell with presentation of food in the dog's mouth, the bell alone would elicit a salivation response similar to the reponse produced by the food.
In drug administration, pairing a stimulus, like a tone, with injection of the drug often causes the tone to produce a compensatory conditioned response; or in other words, the response elicted by the CS (tone) produces effects *opposite* to the drug's effects. This may help to explain tolerance. When environmental events (like the piercing of one's skin with a needle, or the presentation of drug paraphernelia) consistently preceed drug administration, these stimuli may come to elicit a compensatory CR that prepares the body to receive the drug. When this happens, the drug has a weakened effect and abusers get around this by increasing the dosage.
Why is this important to understand? Because when abusers are able to take typically lethal dosages of illicit drugs in one setting, they often attept this in another. The problem with this is that some of the stimuli are different that those that were previously conditioned when they developed tolerance. When an abuser administers a drug in the absence of the appropriate stimuli, their body does not produce the compensatory response and they are at severe risk of overdose.
Secondly, when a tolerant addict encouters the conditioned stimuli *without* administering the drug, they may feel the effects of the compensatory response, and these may be felt as "cravings" or "withdrawl symptoms." These feelings are alleviated by drug administration because the body is already "prepared" to receive the drug. For instance, heroin (an opiate) decreases respiration and heart rates, so as a compensatory response the body increases respiration and heart rates to minimize the effects of the expected drug. When the drug isn't administered, these may still occur with the presentation of appropriate stimuli, and the increased activity is felt as a "craving."
I just thought these were some interesting tid-bits about drug abuse. I'd be willing to bet that similar effects could be found with other addictions and events (like pornography addiction, etc.).
Several studies have shown that drug tolerance may be in large part classically conditioned. It is a well established fact that drug abusers and medicinal patients developed tolerances to drug effects. That is why drug abusers often have to increase their dosage to achieve the same effect, resulting in a more spendy habit that causes many to resort to other crime, like theft. What is interesting is that these tolerances have been shown to often be environmentally specific. What is so interesting about that you ask? First let me explain what I mean by environmentally specific.
Those familiar with classical (respondent or Pavlovian) conditioning already know that when a neutral stimulus is paired in presentation with an unconditioned stimulus (US) that the neutral stimulus comes to elicit a response similar to that of the US. Pavlov's dogs are the classic example. After Pavlov repeatedly paired a bell with presentation of food in the dog's mouth, the bell alone would elicit a salivation response similar to the reponse produced by the food.
In drug administration, pairing a stimulus, like a tone, with injection of the drug often causes the tone to produce a compensatory conditioned response; or in other words, the response elicted by the CS (tone) produces effects *opposite* to the drug's effects. This may help to explain tolerance. When environmental events (like the piercing of one's skin with a needle, or the presentation of drug paraphernelia) consistently preceed drug administration, these stimuli may come to elicit a compensatory CR that prepares the body to receive the drug. When this happens, the drug has a weakened effect and abusers get around this by increasing the dosage.
Why is this important to understand? Because when abusers are able to take typically lethal dosages of illicit drugs in one setting, they often attept this in another. The problem with this is that some of the stimuli are different that those that were previously conditioned when they developed tolerance. When an abuser administers a drug in the absence of the appropriate stimuli, their body does not produce the compensatory response and they are at severe risk of overdose.
Secondly, when a tolerant addict encouters the conditioned stimuli *without* administering the drug, they may feel the effects of the compensatory response, and these may be felt as "cravings" or "withdrawl symptoms." These feelings are alleviated by drug administration because the body is already "prepared" to receive the drug. For instance, heroin (an opiate) decreases respiration and heart rates, so as a compensatory response the body increases respiration and heart rates to minimize the effects of the expected drug. When the drug isn't administered, these may still occur with the presentation of appropriate stimuli, and the increased activity is felt as a "craving."
I just thought these were some interesting tid-bits about drug abuse. I'd be willing to bet that similar effects could be found with other addictions and events (like pornography addiction, etc.).