
07/08/2025
Findings from research on punishment insensitivity in rats can provide a valuable framework for understanding why some horses—often labelled “lazy”—fail to respond to whips and strong leg aids.
In a 2019 study, punishment insensitivity was shown not to result from a reduced capacity to feel pain (aversive insensitivity) or from overwhelming motivation for reward, but rather from a cognitive issue: an impaired ability to detect or learn the contingency between their actions and the punishing consequence.
Translating this to horses, there is mounting evidence and expert opinion indicating that repeated or harsh use of whips and forceful leg aids does not necessarily make “lazy” horses more responsive.
Instead, when horses do not respond, it is often due to either a failure to learn what the punishment is meant to communicate or confusion about which behaviour is being punished.
For example, if the aids are not timed correctly or are applied inconsistently, a horse cannot form a clear mental connection between its own action and the unpleasant stimulus. This mirrors the deficit in contingency detection observed in the rat study.
Overuse of strong aids can cause horses to habituate or become shut down, essentially learning to ignore them as a self-protection against confusing or inescapable signals.
Some horses stop responding to cues not out of stubbornness or high tolerance to discomfort, but because they are no longer able to associate a specific behaviour with a clear outcome. This is consistent with the research paper’s finding that animals may demonstrate punishment insensitivity—not because they feel less, but because they simply cannot link their actions to the consequences.
The paper titled “Punishment insensitivity emerges from impaired contingency detection, not aversion insensitivity or reward dominance,” was published in 2019 in eLife and authored by Philip Jean-Richard-dit-Bressel, Cassandra Ma, Laura A. Bradfield, Simon Killcross, and Gavan P. McNally.