ArticleiScience2021
Behavioral and neurophysiological evidence suggests affective pain experience in octopus.
Article in iScience, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 42 papers, 1 of them a synthesis that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
42 citing papers in PubMed, 1 synthesis or guideline pooled it, 164 citations in OpenAlex.
- Cephalopod Behavior: From Neural Plasticity to Consciousness.Frontiers in systems neuroscience · 2021Pooled it
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- Assessing Local Anesthesia in Octopus bimaculoides to Provide Analgesia.Journal of the American Association for Laboratory Animal Science : JAALAS · 2026Article
- Identification of molecular nociceptors in Octopus vulgaris through functional characterisation in Caenorhabditis elegans.Biology open · 2026Article
- Attribution of consciousness to non-human animals: insights from AI and multidimensional frameworks.Frontiers in psychology · 2026Article
- Towards a neuroethological approach to consciousness.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- From nociception in aneural animals to human suffering: toward a comparative biology of pain.The Journal of experimental biology · 2025Review
- Changing priorities about protective shelters: a review of a key method to investigate possible pain in crustaceans.Biology letters · 2025Review
- Article
- The Persistence of Memory: Behavioral Analysis and Arm Usage of a Nine-ArmedAnimals : an open access journal from MDPI · 2025Article
- A History of Pain Studies and Changing Attitudes to the Welfare of Crustaceans.Animals : an open access journal from MDPI · 2025Review
- Injury alters sensory, motor, and integrative elements underlying operant conditioning in the medicinal leech.PloS one · 2025Article
- Stress produces negative judgement bias in cuttlefish.Biology letters · 2024Article
- Goal-directed behavior in Tenebrio molitor larvae.Scientific reports · 2024Article
- Article
- Article
- The Long Road from Religious and Ethical Traditions to Welfare of Invertebrates.Animals : an open access journal from MDPI · 2024Article
- The Effects of Caustic Soda and Benzocaine on Directed Grooming to the Eyestalk in the Glass Prawn,Animals : an open access journal from MDPI · 2024Article
- Estimating global numbers of fishes caught from the wild annually from 2000 to 2019.Animal welfare (South Mimms, England) · 2024Article
Corrections and comments
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Authors and funding
1 author at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Pain is a negative affective state arising from tissue damage or inflammation. Because pain is aversive and its relief is innately rewarding, animals may learn to avoid a context in which pain is experienced and prefer one where pain relief occurs. It is generally accepted that vertebrate animals experience pain; however, there is currently inconclusive evidence that the affective component of pain occurs in any invertebrate. Here, we show that octopuses, the most neurologically complex invertebrates, exhibit cognitive and spontaneous behaviors indicative of affective pain experience. In conditioned place preference assays, octopuses avoided contexts in which pain was experienced, preferred a location in which they experienced relief from pain, and showed no conditioned preference in the absence of pain. Injection site grooming occurred in all animals receiving acetic acid injections, but this was abolished by local anesthesia. Thus, octopuses are likely to experience the affective component of pain.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.