According to the World Health Organisation (WHO)¹, 180,000 deaths were linked to drug use and abuse in the year of 2019. Addiction can be a serious condition for some, and it has the potential to turn an activity into something that can destroy lives. Many stories in the news revolve around the negative effects of drug addiction, and similarly, those addicted to gambling can also face dire situations.
Addiction usually comes about due to taking or engaging in a behaviour in excess. With consistent use and abuse, the behaviour causes both tolerance and withdrawal symptoms to develop, especially when the person stops performing the addictive behaviour.
- We are going to define tolerance and withdrawal syndrome, providing both a tolerance definition in psychology and a withdrawal symptom definition in psychology.
- We will explore the vulnerabilities in addiction.
- Throughout we will discuss the different types of tolerance in psychology.
Fig. 1 - Tolerance and withdrawal symptoms result from addiction.
Tolerance Definition Psychology
One of the main requirements for a diagnosis of addiction is the build-up of tolerance and the presence of withdrawal symptoms upon stopping. So, let’s define first define tolerance.
Tolerance describes the situation wherein the body has adapted to a substance, drug or behaviour, and taking the same amount will no longer have the same or strong effects.
Once a person has reached a state of tolerance, they will likely feel ‘normal’ taking the drugs and will need to take a lot more, or they will need to engage in more of the behaviour, to elicit the same euphoric or relaxed feelings.
The body has adapted to the drug and needs more to give the same response. As we mentioned above, the new normal for your body is being engaged in drug use (or behaviour, such as gambling). People often learn how to operate whilst under the influence of drugs, for instance.
Without the substance, your body will experience withdrawal symptoms, which we will discuss further later.
Types of Tolerance in Psychology
There are different types of tolerance, but it’s enough to know about the definition and examples for your exam. However, for those interested, tolerance typically is divided into different clinical classes.
Each one affects how much a drug or behaviour affects your system/body and the type of tolerance it develops:
- Acute
- Behavioural
- Dispositional
- Inverse
- Reverse
- Select
- Pharmacodynamic
- Pharmacokinetic
A clear example of tolerance developing is in the case of heroin addiction. Heroin is an opioid made from morphine, a highly addictive substance.
Upon an initial dose of heroin, the euphoric sensation is enough to encourage most to continue taking the drug. However, after a few doses of the same amount, they find the effects are not as strong, and to achieve that euphoric sensation again, they need to take more of the drug. This urge is the result of developing tolerance.
Interestingly, tolerance is not always a sure thing. Whilst a tolerance to a certain drug may develop in one person, another may have no issues at all and can engage in the behaviour without their body adapting too quickly to it, perhaps due to vulnerabilities.
Tolerance also does not always mean addiction has developed.
What are Vulnerabilities in Addiction?
Addiction vulnerability is where someone is more likely to develop an addiction to a substance or behaviour due to pre-existing conditions, behaviours, or genetic influences. It describes the risk of developing an addiction if they engage in addictive behaviours.
For example, both dopamine and serotonin have been linked to addiction due to how the neurotransmitters affect the reward systems, and behaviours and how they control impulsivity. Dopamine itself elicits feelings of pleasure, and serotonin is associated with control.
Abnormal serotonin levels affect the ability to modulate impulsive activities. Abnormal impulsivity levels are a known risk factor for developing an addiction (Kirby et al., 2011). Moeller and Dougherty (2002) investigated how impulsivity levels are related to substance abuse. They found that impulsivity is both a risk factor and a result of substance use.
So, any underlying issues affecting the modulation of serotonin will influence the risk of developing an addiction. Genetic vulnerabilities are also known to exist, as some people have a history of addiction in their families.
For example, a person’s parents may have been addicted to alcohol, so the person avoids alcohol to avoid the risk of developing an addiction.
Heath (1995) investigated through meta-analysis the genetic risks of alcoholism by analysing adoption and twin studies. Heath (1995) found that genetic influence is important in the development of potential issues with alcoholism, and found consistent results across time periods, gender, and testing methods.
Fig. 2 - Vulnerabilities to addiction exist
Withdrawal Symptoms Definition Psychology
As the body has adapted to the drug and adopted the drugged state as the new ‘normal’, it can no longer operate without it, resulting in physical and emotional symptoms.
Withdrawal symptoms in psychology are when the body begins to experience uncomfortable (and sometimes even painful) effects when a person reduces or stops taking a substance or engaging in addictive behaviours.
When the person takes the drug or participates in the behaviour once more, the withdrawal symptoms stop. These symptoms usually manifest as:
Different addictions cause different symptoms. Someone addicted to nicotine will not experience the same withdrawal symptoms as someone addicted to alcohol or even chocolate (which can also be an addiction, believe it or not).
For example, someone with an alcohol addiction will suffer the following withdrawal symptoms:
- Shaky hands
- Vomiting
- Nausea
- Headaches
- Hallucinations
- Seizures
Let’s compare that to withdrawal symptoms resulting from a nicotine addiction:
- Irritability
- Increased hunger/appetite
- Coughing
- Headaches
- Fatigue
- Constipation
We can see that although they have similar symptoms, there are specific symptoms unique to each addiction, some more so than others. Despite the ramifications of addiction, many people continue to indulge in these habits. Some can have long-lasting effects (for instance, smoking and lung cancer, alcohol and liver disease). Yet, despite this, they still cannot stop, and this is because of how powerful addiction can be.
Fig. 3 - Withdrawal symptoms differ depending on the substance.
Tolerance and Withdrawal Syndrome - Key Takeaways
- Tolerance describes the situation wherein the body has essentially adapted to a substance, drug or behaviour, and taking the same amount will no longer have the same or strong effects.
- Upon an initial dose of heroin, the euphoric sensation is enough to encourage most to continue taking the drug, but following doses are not enough to achieve the same high; a tolerance to heroin has been built.
- Withdrawal symptoms in psychology are when the body begins to experience uncomfortable (and sometimes even painful) effects when a person reduces or stops taking a substance or engaging in addictive behaviours.
- These symptoms vary depending on the addiction (an alcoholic quitting drinking will have different withdrawal symptoms than someone quitting smoking).
- Addiction vulnerability is where someone is more likely to develop an addiction to a substance or behaviour due to pre-existing conditions, behaviours, or genetic influences.
References
- World Health Organization. (2019). Drugs. Www.who.int. https://www.who.int/health-topics/drugs-psychoactive#tab=tab_1
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