Images

The distinction between episodic and chronic migraine is made when a person crosses a threshold of 15 monthly headache days, 8 of which meet the criteria for migraine. The division between episodic and chronic is therefore based on the frequency of the migraine symptoms.

The phenomenon of comorbidity is common in psychiatry. Psychiatric comorbidity is common in addiction, with many different psychiatric conditions seen at greater frequency than in the general population.

This infographic provides a visual, at-a-glance overview of the global impact of Substance use disorders and other addictions.

The model focusses on the common underlying risk factors that are shared between several different forms of addiction.

Many regions and circuits in the brain are involved in the control of motivation, which can be dysregulated by substance-use disorders and other addictions. There are four key independent and overlapping circuits implicated in addiction, as shown on image.

The endogenous opioid system of the brain consists of several neurotransmitters that bind in different ways to 3 different G-protein coupled receptors, called the delta (δ), mu (μ), and kappa (κ) receptors.