Neuroadaptation refers to the process whereby the body compensates for the presence of a chemical in the body so that it can continue to function normally. For people who abuse drugs or alcohol, this neuroadaptation leads to tolerance and dependence on a substance.
As a person uses a drug or drinks alcohol more regularly, the body will become used to the presence of the substance and the body will adapt its normal responses accordingly. When neuroadaptation occurs, a person will develop a tolerance and find that they need more of a substance to get the desired effect. Tolerance is known to lead to dependence and addiction. When this occurs, significant changes have occurred in the brain to support the constant presence of drugs or alcohol in the body and a person will feel uncomfortable and in some cases painful symptoms of withdrawals. Withdrawals occur because the body has adapted to the drug and now requires it to maintain normal functioning.
Withdrawals are the symptoms of reversing the development of neuroadaptation to a drug. The symptoms of withdrawals can be unpleasant and sometimes may even prove to be fatal. As well as the physical discomfort the individual will experience, there is a level of psychological pain that a person will also go though. Fear of such effects can discourage people from trying to escape their addiction.
Physical symptoms that a person may experience when withdrawing from drugs or alcohol include body shakes and tremors, nausea, sweating, heart palpitations, muscle aches, seizures, diarrhea, headaches and insomnia. These symptoms can last for a few hours to a few days and in some cases, longer. Many of these symptoms can be managed with support from friends, family or medical professionals to reduce the severity and anxiety associated with them.
Delirium tremens are a particularly severe symptom of withdrawals that is usually associated with chronic alcohol use or benzodiazepines and barbiturates abuse. Those at risk of developing delirium tremens should be monitored by a medical professional as they are potentially fatal. Symptoms include convulsions and seizures, elevated blood pressure, high levels of confusion, agitation and anxiety plus hallucinations.
Dopamine and Neuroadaptation
The chief chemical involved in the brain’s reward pathways is dopamine. Brain processes such as pleasure, cognition, motivation, learning, movement, and memory, among others, may be affected by the number of dopamine receptors as well as their ability to signal a response. Any change in dopamine levels can increase or reduce the number of receptors. Variations in receptor numbers hold the risk of a change in the person’s mental and physical well-being, ranging from mild to severe. Drugs such as cocaine and amphetamine can affect dopamine function either through the stimulation or the blocking of dopamine receptors. By changing the flow of dopamine, these drugs produce their pleasurable effects.
Our physical and mental health can be mildly to greatly affected by the regulation of dopamine in the brain. When dopamine receptors are repeatedly stimulated through drug use, the number of receptors decreases. The receptors that remain can become less sensitive to dopamine, in a process known as desensitization. Drug users know this process as drug tolerance, when the repeated use of the same quantity of a drug causes less of a response than prior use.
Drug abusers are prone to suffering from impaired dopamine activity. Repeated drug use or drug addiction can disrupt the reuptake system, the body’s natural recycling of dopamine. When the body is unable to maintain regular levels of dopamine, consequences such as a change in normal emotional responses or worse, may follow.