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Concepts of Chemical Dependency - Psychoactive Drugs

I need help answering the following question:

How do psychoactive drugs change the way neurons in the central nervous system communicate? Based on your personal observations or experiences, to what extent do you believe these changes are reversible and irreversible? You may consider social, relationship, and biological observations when formulating your response.

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To answer this question, there are a number of considerations you should address.

Firstly, what psychoactive drugs are we examining? There are many, and their effects can be similar or quite opposite to each other. For example, opioids (e.g. morphine) and substances like MDMA (speed) have almost completely opposite effects.

In general, central nervous neurons that are affected by psychoactive drugs must first be able to perceive that the drug is in their immediate surroundings. How do cells do this? They have receptors along various parts of cellular anatomy that these drug molecules can bind to. For example, morphine can bind to a particular opioid receptor that's typically found on cell bodies and axon terminals of the central nervous neurons.

As for what they do to the ability of these neurons to communicate, consider what the drug does after it has bound onto its receptor on a neuron, and how a neuron communicates with other neurons. Let's address the latter point before we continue.

Neurons talk to each other using chemicals called neurotransmitters. There are a good number of them, and all of them can be used for different purposes. For example, glutamate is a neurotransmitter. These neurotransmitters, like glutamate, are released from the ends of these neurons (at their axon terminals), float across a small gap between two neurons called the synapse, and are received by the next neuron at their receiving end (the dendrites). When the second neuron receives a neurotransmitter like glutamate, which binds to its specific ...

Solution Summary

The concepts of chemical dependency for psychoactive drugs are examined.