It's no secret that it feels good to pet a nearby pooch, but a new study confirms it: physically interacting with a dog boosts activity in parts of our brain linked to managing social and emotional interactions.

Researchers used a non-invasive, functional near-infrared spectroscopy (fNRIS) device to measure activity in the prefrontal cortex of 19 study participants. The greater brain activity observed during dog petting suggests the volunteers were more attentive and emotionally engaged at the time.

As a control condition, the participants were also asked to interact with a stuffed lion toy called Leo, who had a hot water bottle inside him to more closely mimic the warmth of a living animal. The brain activity effects weren't the same when the toy was petted.

"The present study demonstrates that prefrontal brain activity in healthy subjects increased with a rise in interactional closeness with a dog or a plush animal, but especially in contact with the dog the activation is stronger," say the researchers behind the study.

"This indicates that interactions with a dog might activate more attentional processes and elicit stronger emotional arousal than comparable nonliving stimuli."

Each study participant was involved in six sessions in all: three with dogs (either a 6-year-old Jack Russel terrier, a 4-year-old Golden Retriever or a 4-year-old Goldendoodle) and three with the plushie, Leo.

Each session had five phases with different levels of interaction: neutral, watching, feeling, stroking, and neutral again.

The greater the interaction, the greater the rise in activity. What's more, these boosting effects of pup interaction lasted after the dog was no longer present, the researchers found, and subsequent interactions with the dogs raised some brain activity levels higher and higher.

That suggests something about familiarity can play a part here. None of the owners of the dogs used in the experiments were included as study participants, which is another area that future studies could look into.

"There seems to be a difference, especially between the first and the second contact with the dog suggesting that familiarity might play a different role in interactions with live and plush animals," write the researchers in their published paper.

Earlier research has shown how time with pooches can lower indicators of stress, such as blood pressure or heart rate. Now it seems that this sort of interaction could help to manage our emotional state as well.

The team behind the study thinks that these findings could have important implications for therapy courses involving canines and other animals – that quality time with a pooch could help those with depression, anxiety, and other related conditions.

However, the subjects involved in this study were all healthy individuals: the next stage would be to see if the same brain effects from petting dogs could be observed in those with social or emotional issues, along with other defined groups of people.

"Future studies should take into account participants' characteristics like gender, pet ownership, and attitude toward animals," write the researchers.

The research has been published in PLOS ONE.