Dopamine

Dopamine is a neurotransmitter — a chemical messenger neurons use to communicate — that plays a central role in regulating motivation, reward, attention, and movement. In ADHD, the dopaminergic system works differently: dopamine isn't efficiently available at the synapses in the brain's prefrontal regions, which makes it harder to voluntarily regulate attention and motivation.

This explains why high-intensity stimuli (video games, social media, risky situations) light up the ADHD brain effectively — they force a bigger dopamine release — while routine, low-stimulation tasks fail to activate the system enough to sustain focus.

Stimulant medications for ADHD (methylphenidate, amphetamines) work by increasing the availability of dopamine at prefrontal synapses, which improves the regulation of attention and behavior.