Pathophysiology and Neurobiology of Substance Use Disorders

What are common symptoms of Substance Use Disorders (SUDs)?

Deception, withdrawal, paranoia, isolation, seeking behavior, and changes in appetite.

What happens to the CNS dopamine pathways during addiction?

The mesolimbic pathway is overstimulated, leading to downregulation of dopamine receptors and depletion of dopamine.

What is the effect of drugs of abuse on dopamine neurotransmission?

They cause overstimulation of the mesolimbic pathway, leading to decreased dopamine signaling and large releases of dopamine.

What role does GABA play in substance use disorders?

GABA is the main inhibitory neurotransmitter that is affected by drugs of abuse, particularly opioids which indirectly inhibit GABA neurons.

How do stimulants affect dopamine pathways?

Stimulants activate the mesolimbic pathway directly, leading to increased dopamine release.

What is the impact of addiction on impulse control?

Impulse control is compromised in addiction, affecting decision-making and behavior.

What are the long-term effects of chronic drug use on dopamine receptors?

Chronic drug use can lead to reduced D2 receptors in the striatum, as shown in PET scans.

What is the significance of the prefrontal cortex in addiction?

The prefrontal cortex is involved in decision-making and impulse control, which are impaired in addiction.

What is the relationship between age and the detriment of addiction?

Younger individuals tend to experience more detrimental effects from addiction.

How do cannabinoids affect dopamine neurons?

Cannabinoids activate dopamine neurons indirectly by inhibiting GABA neurons.

What is the role of the amygdala in addiction?

The amygdala is involved in emotional processing and is affected by substance use, contributing to addiction behaviors.

What is the primary pathway activated by all drugs of abuse?

All drugs of abuse activate the mesolimbic pathway, which is crucial for the reward system.

What is the effect of nicotine on dopamine transmission?

Nicotine directly activates dopamine pathways, enhancing the reward experience.

What are the phases of addiction?

The phases of addiction involve initial use, increased tolerance, dependence, and potential relapse.

What is the consequence of addiction on basic needs like food and water?

When the mesolimbic pathway is hijacked by addiction, individuals may ignore basic needs such as food and water.