Scientists from the University of Innsbruck (Austria) have found that if, after a stressful test, you stroke your dog, the body copes more easily with the next stress. It is true, however, that this does not affect rapid recovery immediately after the first test. The study was published in the journal Biological Psychology.
The experiment involved 66 dog owners, but after screening 64 people remained - 51 women and 13 men, all white Europeans, with an average age of 34. The dogs were healthy, older than two years and accustomed to unfamiliar rooms.
Each participant went through two identical blocks of tests. First a five-minute rest, then a ten-minute stress test: they had to answer questions quickly and count backwards under a flashing red dot. To increase the tension, participants were told they were being video-recorded, and an observer via video link gave only critical remarks. After the test - a minute of rest, then five minutes of recovery with the dog and another five minutes of rest.
The difference between the blocks was only in the recovery phase. In one case the dog could walk freely and the owner could stroke it. In the other, the dog was kept on a short leash out of reach: touching was not allowed, but talking and looking into its eyes were permitted.
During rest and stress, the scientists recorded the brain's electrical activity using electroencephalography (EEG) - a method in which a cap with sensors is placed on the head. They tracked alpha waves (slow rhythms associated with relaxation) and beta waves (fast rhythms associated with tension and attention). They also measured heart rate and heart rate variability - fluctuations in the time between heartbeats that reflect the work of the calming parasympathetic nervous system.
The stress test did indeed provoke a reaction: alpha waves fell, beta waves rose, the heart rate increased, and variability decreased. When participants were allowed to stroke the dog, they did so for about 64% of the recovery time - roughly three minutes twelve seconds. If touching was not allowed, people looked into the dogs' eyes longer - on average 53 seconds more.
Contrary to expectations, stroking did not speed recovery: by the end of the rest, brain, heart and mood indicators returned to baseline roughly equally in both cases. The effect did, however, appear later. Those who stroked the dog after the first stress showed a calmer reaction during the second test: less suppression of alpha waves, a slower heart rate and higher heart rate variability. Those who were deprived of tactile contact showed no such shifts.
"Our results show that physical contact with a pet can reduce the strength of the body's reaction to subsequent stress," says co-author Vanessa Kaufmann. "It is interesting that the subjective feeling of stress did not differ, meaning that physiological buffering may occur without awareness."
The authors emphasise: the effects were moderate but consistent across different measures. However, it remains unclear how this translates to real life. In addition, the protective effect was found in an additional (exploratory) analysis, so it requires confirmation in a specially designed study. It also cannot be ruled out that stroking changed the effort invested in the second test. The sample was homogeneous - about 80% women, all white Europeans. Finally, participants dealt with their own dogs, not unfamiliar animals.
"Physical contact with another being should always be mutual and pleasant," the researchers remind.