Myth or fact? The dopamine quiz
Twelve things people say about dopamine. For each one, decide: true, false, or is it complicated? Then see what the evidence actually says.
Claim 1 of 12
“Dopamine is the brain’s pleasure chemical.”
The answer: False.
Dopamine is mainly about wanting and effort — deciding something is worth going after. The enjoyment itself (“liking”) survives near-total dopamine loss in animal studies and runs largely on other systems.
Evidence grade A · Read the full evidence
“Social media gives you a dopamine hit.”
The answer: It’s complicated.
Feeds deliver unpredictable rewards, and dopamine neurons respond strongly to uncertain rewards — that part is real. But the human studies of likes and feeds measure blood flow on brain scans, not dopamine, and whether “addiction” is the right word is still disputed.
Evidence grade C · Read the full evidence
“A cold shower raises your dopamine by 250%.”
The answer: False.
The figure comes from one small study of neck-deep cold-water immersion for an hour, and it measured dopamine in blood plasma, not in the brain. A similar study found no significant rise. No study has measured brain dopamine during a cold shower.
Evidence grade C · Read the full evidence
“Dopamine is only found in the brain.”
The answer: False.
Dopamine is also made in the kidney, gut, pancreas and immune cells, where it helps with things like sodium balance and blood pressure — separate biology from mood or motivation.
Evidence grade B · Read the full evidence
“A “dopamine detox” resets your dopamine receptors.”
The answer: False.
Everyday stimulation does not deplete dopamine in the way the idea assumes. Cutting screen time has been tested in trials, with mixed and mostly short-lived results — the behaviour can help a little; the explanation is wrong.
Evidence grade E · Read the full evidence
“Coffee affects your brain’s dopamine system.”
The answer: True.
Yes, but indirectly. Caffeine blocks adenosine receptors, which boosts dopamine signalling as a knock-on effect. In one brain-imaging study, simply expecting caffeine produced a similar dopamine change on its own.
Evidence grade B · Read the full evidence
“Sugar is as addictive as cocaine.”
The answer: False.
The claim rests mostly on rats fed sugar in a very specific restricted pattern. Craving sweet food is real, but careful reviews of the human evidence find it does not look like drug addiction.
Evidence grade C · Read the full evidence
“ADHD is caused by low dopamine.”
The answer: It’s complicated.
Dopamine signalling does work differently in ADHD, and stimulant medicines act on it. But imaging studies disagree even on the direction of any difference, and genetic risk is spread across many genes, most not dopamine-specific.
Evidence grade B · Read the full evidence
“A night without sleep changes dopamine signalling in the brain.”
The answer: True.
Several independent brain-imaging (PET) studies find that one night of sleep loss changes dopamine receptor measurements in the striatum, linked to lower alertness. Exactly why is still debated.
Evidence grade B · Read the full evidence
“Music you love can release dopamine in the brain.”
The answer: True.
A brain-imaging (PET) study found dopamine release during intensely pleasurable moments in music. It is a real, well-cited finding — but from one small study.
Evidence grade B · Read the full evidence
“Our attention spans are now shorter than a goldfish’s.”
The answer: False.
The “8 seconds” figure traces back to an uncredited marketing statistic, not a peer-reviewed study, and there is no comparable measurement from decades ago to compare against.
Evidence grade ? · Read the full evidence
“Playing video games can release dopamine in the brain.”
The answer: True.
A landmark 1998 PET study showed measurable dopamine release in the striatum while people played a video game — more in those who played better.
Evidence grade C · Read the full evidence
You called correctly.
Most people find at least a few of these surprising — “dopamine” is used to explain far more than the research supports. Every answer links to the full evidence, with the studies and their limitations.
The score is just a count of answers that matched the evidence. It says nothing about you, and nothing you choose is stored or sent anywhere.
How we decide the answers
Each answer summarises a longer page where the claim is graded under the dopamine.co.uk Evidence Standard. “It’s complicated” means part of the claim is supported and part is not — usually a real finding stretched further than the evidence goes.