For many, bad grammar can be maddening.
Now experts have discovered it really does cause a physical reaction – and even affects our heart rate.
Instances of bad grammar can include mixing up tenses within a sentence, confusing the singular and plural, using a double negative or misusing a comma.
Examples of the pet peeve include 'We don't need no education', 'I ate porridge for breakfast and drink milk' or 'Anna and Mike is going skiing'.
Researchers from the University of Birmingham recruited 41 British English-speaking adults who listened to 40 English speech samples, half of which contained grammatical errors.
For many, bad grammar can be maddening. Now experts have discovered it really does cause a physical reaction – and even affects our heart rate (stock image)
They recorded the participants' heart rate variability (HRV) as they listened to the extracts.
HRV captures the time between successive heart beats.
These intervals tend to be variable during a relaxed state but become more regular when a person is stressed.
Analysis revealed the more errors a person heard, the more regular their heartbeat became – a sign of stress.
The researchers said grammatical errors appear to activate a 'fight or flight' response within the human body.
They explained that knowledge about a first language is largely implicit, as most people did not need to sit and study to learn their mother tongue.
And this could mean that our body reacts to bad grammar even if we cannot pinpoint exactly what is wrong within a sentence.
Professor Dagmar Divjak, principal investigator of the study, said: 'Your knowledge about your first language is largely implicit, i.e., learning your mother tongue did not require you to sit and study, and using it does not require much, if any, thought.
'This also means that you will find it hard to pin down what exactly is right or wrong about a sentence and, even worse, explain why that is so, especially if you've not had formal language training.'
The findings, published in the Journal of Neurolinguistics, read: 'The model confirmed that there is a cardiovascular response to grammatical violations.
'We registered a statistically significant reduction in HRV…in response to stimuli that contain errors.
'The observation that linguistic knowledge can be detected using cardiovascular measures brings into focus a new dimension of the intricate relationship between physiology and cognition and opens up new pathways for exploring this link.'