Exposure to certain situations or stimuli can alter us to the point of triggering stress symptoms. Have you ever felt a small nervous twitch or a slight discomfort when hearing a grammatical error in a commentator on TV or your interlocutor at a group dinner? You’re not alone. A recent study by a group of professors at the University of Birmingham has discovered why our bodies go into stress mode when they hear someone speak with poor grammar. Specifically, their research has found a direct connection between instances of poor grammar and heart rate variability, or HRV, which measures the time between successive heartbeats.
The length of the intervals between a person’s successive heartbeats tends to be variable when he or she is relaxed, but becomes more regular when he or she becomes stressed. The new study shows that a statistically significant reduction in HRV occurs in response to grammatical transgressions. This reduction reflects the extent of grammatical errors, suggesting that the more errors a person hears, the more regular their heartbeat becomes, a sign of stress.
“The results of this study highlight a new dimension of the intricate relationship between physiology and cognition. This relationship has been studied using techniques ranging from eye tracking to electroencephalography or brain imaging. But until now the relationship between language cognition and the autonomic nervous system (ANS) has received less attention,” says Professor Dagmar Divjak, Professor in Cognitive Linguistics and Language Cognition at the University of Birmingham and principal investigator of the study.
A key link between cognition and physiological response
“The ANS consists of two parts: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). Simply put, the sympathetic nervous system activates the ‘fight or flight response’ during a perceived threat or danger, while the parasympathetic nervous system controls the functions of rest and digest, or feeding and reproduction. “Our findings show that this system also responds to cognitive demands, and this suggests that cognitive effort has greater repercussions on the physiological system than previously thought,” he explained.
“Our findings suggest that cognitive effort has greater repercussions on the physiological system than previously thought”
According to this expert, an individual’s knowledge of their native language is largely implicit, that is, learning their native language has not required them to sit down and study, and its use does not require much effort either. This also means that you will find it difficult to pin down what exactly is right or wrong in a sentence and, even worse, to explain why it is that way, especially if you have had no formal language training.
“However,” says Divjak, “precisely evaluating the language skills of a person, regardless of his or her age and physical or cognitive abilities, is important for many issues related to core areas of life related to cognition, including brain health”. “This study provides us with a new method to harness aspects of cognition that are not directly observable. This is particularly valuable in working with language users who cannot verbally express their opinion due to their youth or old age, or poor health,” she concludes.
Research carried out by Dagmar Divjak alongside Petar Milin, Professor of the Psychology of Language and Language Learning at the University of Birmingham, and Dr Hui Sun, who was working as a postdoctoral researcher on the project at the time, has provided the first evidence to suggest that HRV can be used as an indicator of implicit linguistic knowledge. The results have been published in the journal Journal of Neurolinguistics.