Home › Research › Tau biomarkers
Intranasal insulin improves memory in humans
Benedict C, Hallschmid M, Hatke A, Schultes B, Fehm HL, Born J, Kern W.. Psychoneuroendocrinology, 2004-11-01
Topic: Gut, metabolism and diet
Previous studies have suggested an acutely improving effect of insulin on memory function. To study changes in memory associated with a prolonged increase in brain insulin activity in humans, here we used the intranasal route of insulin administration known to provide direct access of the substance to the cerebrospinal fluid compartment. Based on previous results indicating a prevalence of insulin receptors in limbic and hippocampal regions as well as improvements in memory with systemic insulin administration, we expected that intranasal administration of insulin improves primarily hippocampus dependent declaration memory function. Also, improvements in mood were expected. We investigated the effects of 8 weeks of intranasal administration of insulin (human regular insulin 4 x 40 IU/d) on declarative memory (immediate and delayed recall of word lists), attention (Stroop test), and mood in 38 healthy subjects (24 males) in a double blind, between-subject comparison. Blood glucose and plasma insulin levels did not differ between the placebo and insulin conditions. Delayed recall of words significantly improved after 8 weeks of intranasal insulin administration (words recalled, Placebo 2.92 +/- 1.00, Insulin 6.20 +/- 1.03, p < 0.05). Moreover, subjects after insulin reported signs of enhanced mood, such as reduced anger (p < 0.02) and enhanced self-confidence (p < 0.03). Results indicate a direct action of prolonged intranasal administration of insulin on brain functions, improving memory and mood in the absence of systemic side effects. These findings could be of relevance for the treatment of patients with memory disorders like in Alzheimer's disease.
Key findings
- To study changes in memory associated with a prolonged increase in brain insulin activity in humans, here we used the intranasal route of insulin administration known to provide direct access of the substance to the cerebrospinal fluid compartment.
- Based on previous results indicating a prevalence of insulin receptors in limbic and hippocampal regions as well as improvements in memory with systemic insulin administration, we expected that intranasal administration of insulin improves primarily hippocampus dependent declaration memory function.
- Delayed recall of words significantly improved after 8 weeks of intranasal insulin administration (words recalled, Placebo 2.92 +/- 1.00, Insulin 6.20 +/- 1.03, p < 0.05).
- Results indicate a direct action of prolonged intranasal administration of insulin on brain functions, improving memory and mood in the absence of systemic side effects.
- These findings could be of relevance for the treatment of patients with memory disorders like in Alzheimer's disease.
New to this subject? Start with our plain-English guide: Blood tests & biomarkers →
Study details
- Evidence strengthLow
How this study scored 64/100
Published in a peer-reviewed journal, and it is a randomised controlled trial. Scored zero for sample size and effect reported because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 37 of the 58 points we could judge it on, which is 64 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Psychoneuroendocrinology) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 11 / 12 | A randomised controlled trial (from PubMed type “Randomized Controlled Trial”) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2004 — older than 20 years, still counted |
| 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 | 3 / 3 | Studied in people (pubmed indexes it as a clinical or observational study) |
| Randomised / blinded | 2 / 2 | Randomised and blinded or placebo-controlled (as stated in the record) |
| Times cited | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| 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 | — / 6 | Not yet checked against this library's citation graph — left out of this score |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 15288712) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 37 / 58 | Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 37 of the 58 points we could judge it on is 64 out of 100. |
| Total | 64 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
Free copy unknown: no free-copy check has an answer for this record yet. That does not mean it is paywalled.
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 names 7 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Benedict, C., Hallschmid, M., Hatke, A., Schultes, B., Fehm, H. L., Born, J., et al. (2004). Intranasal insulin improves memory in humans. Psychoneuroendocrinology. https://doi.org/10.1016/j.psyneuen.2004.04.003
Vancouver
Benedict C, Hallschmid M, Hatke A, Schultes B, Fehm HL, Born J, et al. Intranasal insulin improves memory in humans. Psychoneuroendocrinology. 2004. doi:10.1016/j.psyneuen.2004.04.003. PMID: 15288712.
BibTeX
@article{benedict2004-15288712,
author = {Benedict, C. and Hallschmid, M. and Hatke, A. and Schultes, B. and Fehm, H. L. and Born, J. and Kern, W.},
title = {{Intranasal insulin improves memory in humans}},
journal = {Psychoneuroendocrinology},
year = {2004},
doi = {10.1016/j.psyneuen.2004.04.003},
pmid = {15288712},
url = {https://doi.org/10.1016/j.psyneuen.2004.04.003}
}
Related studies in Tau biomarkers
Also tagged “agonists”
285 studies in the library carry the topic tag “agonists”; these are this study's neighbours in a fixed, alphabetical-by-hash tour of them, not the closest in content. All 285 tagged studies.