Research data ยท Fear and avoidance
Fear conditioning
From 2021 to 2025, 2,010 animal research papers mentioned fear conditioning in their title or abstract, ranking it seventh of the 90 tests we track.
That is about the same as the 2,034 papers of 2011 to 2015. Papers that mention any of the 90 tests rose 22% over the same span. The 2021 to 2025 count may run low because of a dip in PubMed's indexing, explained under the year chart.
Papers by year
Animal research papers that mention fear conditioning, by year, 2001 to 2026
The 2026 bar counts papers added to PubMed by November 8, 2026.
- Papers in a full year
- 2026 so far
Show the counts for each year
| Year | Papers |
|---|---|
| 2001 | 127 |
| 2002 | 155 |
| 2003 | 187 |
| 2004 | 186 |
| 2005 | 198 |
| 2006 | 249 |
| 2007 | 240 |
| 2008 | 301 |
| 2009 | 313 |
| 2010 | 318 |
| 2011 | 330 |
| 2012 | 386 |
| 2013 | 424 |
| 2014 | 489 |
| 2015 | 405 |
| 2016 | 467 |
| 2017 | 427 |
| 2018 | 466 |
| 2019 | 454 |
| 2020 | 428 |
| 2021 | 478 |
| 2022 | 405 |
| 2023 | 370 |
| 2024 | 378 |
| 2025 | 379 |
| 2026 (part year) | 353 |
Papers that mention fear conditioning fell from 478 in 2021 to 370 in 2023, then rose to 379 in 2025. Papers that PubMed indexed under the MeSH heading Animals also fell and rose, from 200,221 in 2021 to 156,447 in 2023 and 235,479 in 2025. We take each paper's species from PubMed's indexing whenever it names one, so part of this dip may come from the indexing rather than from fewer studies.
Papers that mention fear conditioning in mice and in rats, by year, 2001 to 2025
- Mouse
- Rat
Show the counts for each year and species
| Year | Mouse | Rat |
|---|---|---|
| 2001 | 32 | 83 |
| 2002 | 43 | 94 |
| 2003 | 65 | 99 |
| 2004 | 53 | 119 |
| 2005 | 70 | 110 |
| 2006 | 69 | 162 |
| 2007 | 101 | 120 |
| 2008 | 106 | 177 |
| 2009 | 126 | 165 |
| 2010 | 139 | 167 |
| 2011 | 150 | 163 |
| 2012 | 181 | 170 |
| 2013 | 186 | 219 |
| 2014 | 252 | 219 |
| 2015 | 189 | 185 |
| 2016 | 238 | 206 |
| 2017 | 219 | 181 |
| 2018 | 235 | 205 |
| 2019 | 245 | 185 |
| 2020 | 233 | 179 |
| 2021 | 272 | 178 |
| 2022 | 228 | 153 |
| 2023 | 218 | 127 |
| 2024 | 230 | 121 |
| 2025 | 226 | 129 |
Which species the papers used
Each bar is a share of the 2,010 papers from 2021 to 2025. A paper can use more than one species, so the shares can add to more than 100%.
Species
โOther animalsโ counts papers that use none of the other species in this chart.
Strains and genetic lines
Strain names come from the MeSH terms PubMed adds when it indexes a paper. PubMed has indexed 1,698 of the 2,010 papers, so each bar is a share of those 1,698.
A paper indexed under two of these headings, such as knockout mice and a strain, counts under both.
Disease models these papers study
Each bar counts the papers from 2021 to 2025 that mention fear conditioning and study that disease model, with its share of the 2,010 papers. The model comes from a paper's MeSH terms. For a paper PubMed has not indexed, it comes from PubTator 3, NCBI's text-mining service, when that service finds the disease in the title or abstract. A paper can count under more than one model.
Papers from 2021 to 2025 by disease model
Tests mentioned alongside fear conditioning
Each bar counts the papers from 2021 to 2025 that mention both tests, with its share of the 2,010 papers that mention fear conditioning.
Papers from 2021 to 2025 that mention both tests
The most cited papers from 2021 to 2025
These papers from 2021 to 2025 mention fear conditioning and have the most citations, as counted by NIH's iCite on November 5, 2026. We show four of the five most cited papers and leave out one because of words in its title.
Brain Behav Immun, 2021. 216 citations.
Representational drift in primary olfactory cortex.
Nature, 2021. 214 citations.
Nat Commun, 2022. 192 citations.
Front Immunol, 2021. 150 citations.
How we counted
A count is the number of animal research papers whose title or abstract mentions one of the test's search terms. It is not a count of experiments, labs or animals.
A paper that mentions fear conditioning only in its methods is missed, so the count runs low. The count includes 101 reviews. For 313 of the 2,010 papers, PubMed's indexing gave no species, so the species came from PubTator 3 finding one in the title or abstract.
The test's search terms are in the test list download. The full method, with each source and its terms of use, is on our main page, Behavioral tests in published research.
More fear and avoidance tests
These fear and avoidance tests also have a page, with their papers from 2021 to 2025. Each test with 30 or more papers gets one.
How to cite
APA
ConductScience. (2026, November 10). Fear conditioning in published research [Data set]. https://conductscience.com/data/behavioral-tests/fear-conditioning
BibTeX
@misc{conductscience_fear_conditioning_2026,
author = {{ConductScience}},
title = {Fear conditioning in published research},
year = {2026},
month = nov,
url = {https://conductscience.com/data/behavioral-tests/fear-conditioning},
note = {Data set, released November 10, 2026},
}Apparatus for fear conditioning
Our store sells one product for fear conditioning.
Shop the apparatusPapers that name our apparatus
We keep our own list of published papers whose text names our equipment. Those that mention fear conditioning in the title or abstract are already in the counts above.
- 13 papers from 2020 to 2026 name our Fear Conditioning System. See the papers
