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Dopaminergic therapy selectively amplifies hallucination susceptibility in patients with Parkinson's disease with cortico-striatal hyperconnectivity
Bernasconi, F.; Stampacchia, S.; Burget, L.; Potheegadoo, J.; Maradan, M.; Habiby Alaoui, S.; Catalano Chiuve, S.; Van De Ville et al.. medRxiv (preprint), 2026-09-03
Topic: Brain proteins, microglia and lab models
Dopamine replacement therapy (DRT) alleviates motor symptoms in Parkinsons disease (PD) but can trigger hallucinations in a subset of patients, yet the neural basis of this selective vulnerability is unknown. Hallucinations are among the most disabling non-motor symptoms of PD, linked to social isolation, dementia and institutionalization. Using a validated robotic paradigm to induce and quantify hallucinations in real-time, combined with resting-state fMRI in a crossover On/Off DRT design, we studied patients with PD with (PD-H) and without (PD-nH) hallucinations. DRT selectively amplified sensitivity to robot-induced hallucinations in patients with pre-existing hallucinatory phenotype (PD-H, but not PD-nH) and was accompanied by cortico-striatal and large-scale network hyperconnectivity. Rather than supporting a uniform hallucinogenic effect of dopamine in PD, these findings indicate that DRT interacts with an intrinsic neural vulnerability that varies in patients. Prospective studies will establish whether this pharmacological-behavioural signature identifies patients at risk before clinical hallucinations emerge.
Key findings
- Rather than supporting a uniform hallucinogenic effect of dopamine in PD, these findings indicate that DRT interacts with an intrinsic neural vulnerability that varies in patients.
Why it matters
This study found that dopamine replacement therapy increased sensitivity to induced hallucinations only in Parkinson's patients who already had hallucinations, linked to cortico-striatal hyperconnectivity. It concerns Parkinson's disease hallucinations and does not test any treatment, cure or prevention for Alzheimer's disease.
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Study details
- Evidence strengthLow
How this study scored 16/100
Preprint — not yet peer-reviewed. It scored 22 on the same rubric, but non-peer-reviewed sources are capped at 16, so it shows as 16. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on impact for its field and year, so that was left out: it earned 21 of the 94 points we could judge it on, which is 22 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 2 / 10 | Tier 4 — not a peer-reviewed journal (medRxiv (preprint)) |
| Journal's citation record | 0 / 4 | Not a journal article, so the journal's record does not count |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 4 / 10 | Preprint — not yet peer-reviewed. Hosted on a preprint server. |
| How recent | 5 / 5 | 2026 — within 1 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 0 / 7 | Cited 0 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.0 citations a year over 2 year(s) since 2026 |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 0 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Olaf Blanke: h-index 81 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | École Polytechnique Fédérale de Lausanne: institution h-index 1,186 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 5 institution(s) in 1 country |
| Indexed in PubMed | 1 / 2 | Not in PubMed, but has a DOI |
| Free to read | 2 / 2 | Free to read |
| Points | 21 / 94 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 21 of the 94 points we could judge it on is 22 out of 100. |
| Total | 22 / 100 | Capped to 16 because this is not a peer-reviewed article. |
What each of these 20 components measures, and what this score is not →
Read the original
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Bernasconi, F., Stampacchia, S., Burget, L., Potheegadoo, J., Maradan, M., Habiby Alaoui, S., et al. (2026). Dopaminergic therapy selectively amplifies hallucination susceptibility in patients with Parkinson's disease with cortico-striatal hyperconnectivity. medRxiv (preprint). https://doi.org/10.64898/2026.09.01.26361921
Vancouver
Bernasconi F, Stampacchia S, Burget L, Potheegadoo J, Maradan M, Habiby Alaoui S, et al. Dopaminergic therapy selectively amplifies hallucination susceptibility in patients with Parkinson's disease with cortico-striatal hyperconnectivity. medRxiv (preprint). 2026. doi:10.64898/2026.09.01.26361921.
BibTeX
@article{bernasconi2026-bb689293,
author = {Bernasconi, F. and Stampacchia, S. and Burget, L. and Potheegadoo, J. and Maradan, M. and Habiby Alaoui, S. and Catalano Chiuve, S. and De Ville, Van and others},
title = {{Dopaminergic therapy selectively amplifies hallucination susceptibility in patients with Parkinson's disease with cortico-striatal hyperconnectivity}},
journal = {medRxiv (preprint)},
year = {2026},
doi = {10.64898/2026.09.01.26361921},
url = {https://doi.org/10.64898/2026.09.01.26361921}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.