In 66 healthy volunteers, three weeks of escitalopram dulled the response to reward and punishment
Double-blind, placebo-controlled, in people without depression: escitalopram 20 mg for at least 21 days reduced reinforcement sensitivity on two learning tasks. Memory, inhibition and flexibility: unchanged. The authors link it to blunting.
Reasonable evidence with real limitations. how we score evidence
Caveat on this rating: Sixty-six healthy people, one dose, three weeks, and a laboratory task rather than a reported feeling; the authors say the result 'may reflect' blunting. Semi-randomised allocation. No other cognitive measure changed. It says nothing about duration, reversibility or patients with depression.
The experiment that separates the drug from the depression, by giving the drug to people who do not have the depression.
Significant findings
Langley, Armand, Luo and colleagues at the University of Copenhagen ran a double-blind placebo-controlled study in 66 healthy volunteers, semi-randomised to 20 mg of escitalopram (32 people) or placebo (34), balanced for age, sex and IQ, for at least 21 days. They measured "cold" cognition (inhibition, cognitive flexibility, memory) and "hot" cognition (decision-making and especially reinforcement learning), with questionnaires and serum escitalopram levels alongside.
"The novel and important finding was that escitalopram reduced reinforcement sensitivity compared to placebo on both the Sequential Model-Based/Model-Free task and the PRL task." Reinforcement sensitivity is how much a person's choices shift in response to reward and punishment. "We found no other significant group differences on 'cold' or 'hot' cognition."
The link the authors draw: "Lower reinforcement sensitivity in response to chronic SSRI administration may reflect the 'blunting' effect often reported by patients with MDD treated with SSRIs." The study is registered as NCT04239339.
The other direction
Sixty-six people, one drug, one dose, three weeks. The measure is a task score in a lab, not a feeling; the abstract does not report that the escitalopram group felt flatter, only that their learning responded less to reward and punishment. The authors write "may reflect," not "is." Semi-randomised means allocation was balanced by hand on age, sex and IQ rather than fully random. And nothing else changed: memory, inhibition and flexibility were intact, which is a finding in the drug's favour as much as against it.
What this does not show
It does not say how the effect behaves over months, or whether it fades after stopping. It was done in people without depression, so it cannot say how the same effect plays out in someone whose illness already dulls reward. It is not a reason to change a prescription.
Worth asking
If part of my flatness is the drug, what are the options, and what does each one risk for the mood it is holding?
Source
Chronic escitalopram in healthy volunteers has specific effects on reinforcement sensitivity: a double-blind, placebo-controlled semi-randomised study — Langley C, Armand S, Luo Q, Savulich G, Segerberg T, Søndergaard A, Pedersen EB, Svart N, Overgaard-Hansen O, Johansen A, Borgsted C, Cardinal RN, Robbins TW, Stenbæk DS, Knudsen GM, Sahakian BJ (2023)
Top-tier peer-reviewed journal
Read the source: https://doi.org/10.1038/s41386-022-01523-x
DOI: 10.1038/s41386-022-01523-x
How this was scored
- Study design
- Randomised controlled trial
- Funding
- Funding not disclosed
- Published in
- Top-tier peer-reviewed journal
- Sample size
- 66
- Preregistered
- Yes
- Conflicts disclosed
- not recorded
- Independent of proponent
- not recorded
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published September 29, 2026.
Questions
How strong is the evidence behind this?
veisund rates this source "moderate evidence". Reasonable evidence with real limitations. It scores 66 out of 100 on our published rubric. One caveat travels with that badge: Sixty-six healthy people, one dose, three weeks, and a laboratory task rather than a reported feeling; the authors say the result 'may reflect' blunting. Semi-randomised allocation. No other cognitive measure changed. It says nothing about duration, reversibility or patients with depression. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Chronic escitalopram in healthy volunteers has specific effects on reinforcement sensitivity: a double-blind, placebo-controlled semi-randomised study — Langley C, Armand S, Luo Q, Savulich G, Segerberg T, Søndergaard A, Pedersen EB, Svart N, Overgaard-Hansen O, Johansen A, Borgsted C, Cardinal RN, Robbins TW, Stenbæk DS, Knudsen GM, Sahakian BJ (2023). Published in: Top-tier peer-reviewed journal. DOI: 10.1038/s41386-022-01523-x. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Randomised controlled trial. Funding: Funding not disclosed. Independence from the proponent is not recorded. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.