Stress hormones can cause memory disorders and atrophy of the hippocampus which is associated with memory disorders

Memory Disorders and Stress 

Individuals under stress are most likely to suffer from frequent illness due to an impaired immune system. 

Stress and Immune system 

Chronic stress may result in atrophy of the brain mass as well as decrease its weight. These differences in cognition, memory and stress. 

Skidmore College

Negative Reinforcement: Pain avoidance

Positive Reinforcement: Pleasure seeking

Incentive Salience: Craving

Stimulus Response Learning: Habits

Inhibitory Control Dysfunction: Impulsivity 

Theories of Addiction

Yaribeygi, H., Panahi, Y., Sahraei, H., Johnston, T. P., & Sahebkar, A. (2017). The impact of stress on body function: A review. EXCLI journal, 16, 1057–1072. https://doi.org/10.17179/excli2017-480

The impact of stress on body function: A review

Newton, T. F., De La Garza, R., Kalechstein, A. D., Tziortzis, D., & Jacobsen, C. A. (2009). Theories of Addiction: Methamphetamine Users’ Explanations for Continuing Drug Use and Relapse. The American Journal on Addictions, 18(4), 294–300. https://doi.org/10.1080/10550490902925920

Addiction theories in methamphetamine users

Negative reinforcement, defined as the removal of an unpleasant stimulus, was one of the earliest theories proposed to explain addictive behavior.

The basic idea is that drug/alcohol use reduces the negative symptoms of withdrawal, which prompts users in acute withdrawal to engage in drug use to lessen the effects of these negative symptoms. Withdrawal is associated with a negative emotional state and symptoms such as anxiety, chronic irritability, malaise, dysphoria, sleep disturbances, physical pain and fatigue, and decreased pain thresholds. Acute withdrawal is linked to decreased activity of the mesocorticolimbic dopamine system and neuroadaptive changes in the nucleus accumbens.

Negative Reinforcement in Addiction

Positive reinforcement, defined as the introduction of a desirable stimulus, can often be seen in the early stages of drug addiction and drug-seeking habit formation as the theory states users take the drug because they enjoy the drug and its effects. Positive reinforcement may also play a factor in quickly reintroducing drug habits after periods of abstinence.

Positive Reinforcement in Addiction

The stimulus response learning theory relates addictive behavior to habit formation and learning, where drug-related stimuli prompts a habitual response to take the drug. It has been hypothesized that repeated drug use elicits changes in dopamine receptors in the dorsal striatum that result in drug-seeking habits that are challenging to give up despite negative outcomes.
Other important elements of this theory include conditioned reinforcement and impulsivity.

Stimulus Response Learning in Addiction

The Incentive Salience theory of addiction attributes addictive behavior to sensitization of neural systems caused by repeated drug use that ultimately make the user “crave” the drug. Once a neural system has become sensitized to a drug, the drug becomes highly salient, or wanted and desired, by the user. Thus, increased exposure and repeated use results in the drug becoming increasingly desirable to the user. As the neural systems associated with wants and desires become continuously sensitized, drug-related stimuli has more control over behavior as wants/desires develop into cravings.

Incentive Salience in Addiction

The inhibitory control dysfunction theory attributes addictive behavior to impulsivity. Under this theory, the inhibitory system, which is involved in response inhibition and response selection, guides compulsive behavior that is associated with drug addiction. The loss of control over drug-associated behaviors suggests that addicted users are unable to efficiently regulate the reward system in their brain.

Inhibitory Control Dysfunction in Addiction

May, A. C., Aupperle, R. L., &amp; Stewart, J. L. (2020). Dark Times: The role of negative reinforcement in methamphetamine addiction. Frontiers in Psychiatry, 11. https://doi.org/10.3389/fpsyt.2020.00114 

Dark Times: The role of negative reinforcement in methamphetamine addiction

People engage in drugs despite negative consequences because it alleviates negative, uncomfortable, unfavorable mental states and moods. Including withdrawal. 

Negative Reinforcement and Drugs

Cho, S. B., Su, J., Kuo, S. I.-C., Bucholz, K. K., Chan, G., Edenberg, H. J., McCutcheon, V. V., Schuckit, M. A., Kramer, J. R., &amp; Dick, D. M. (2019). Positive and negative reinforcement are differentially associated with alcohol consumption as a function of alcohol dependence. Psychology of Addictive Behaviors, 33(1), 58–68. https://doi.org/10.1037/adb0000436 

Positive and Negative Reinforcement are Differentially Associated with Alcohol Consumption as a Function of Alcohol Dependence

Positive reinforcement would be the positive, and or alleviating feelings that drugs provide the individual.

Positive Reinforcement 

Robinson, M. J. F., Robinson, T. E., &amp; Berridge, K. C. (2013). Incentive salience and the transition to addiction. Biological Research on Addiction, 391–399. https://doi.org/10.1016/b978-0-12-398335-0.00039-x 

 Incentive salience and the transition to addiction. 

Is the feeling of wanting, and this wanting is intense and present in conscious awareness. 

Incentive Salience: Wanting 

Habits is when you act on incentive salience, and it is it’s persistent quality that becomes dangerous. 

Stimulus-Response Learning: Habits 

Jentsch, J. D., &amp; Taylor, J. R. (1999). Impulsivity resulting from Frontostriatal dysfunction in drug abuse: Implications for the control of behavior by reward-related stimuli. Psychopharmacology, 146(4), 373–390. https://doi.org/10.1007/pl00005483 

 Impulsivity resulting from Frontostriatal dysfunction in drug abuse: Implications for the control of behavior by reward-related stimuli.

The inability to inhibit both unconditioned and conditioned responses. 

Inhibitory Control Dysfunction: Impulsivity

Impulsivity resulting from Frontostriatal dysfunction in drug abuse: Implications for the control of behavior by reward-related stimuli.

Drug Seeking Behavior has been tied to two phenomena
- "augmented incentive motivational qualities of the drug and associated stimuli"
- " impaired inhibitory control "

Drug Seeking Behavior - 2 phenomena 

Stress can cause structural changes in parts of the brain.

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