This essay was originally posted on Psychology Today.
Citizen science can help us understand how dogs react to “faceless” humans.
There aren’t any sweeping one-size-fits-all explanations even for a single dog.
It’s well known that many dogs watch us carefully and read our faces very well using specific parts of their brains. Given the prevalence of masked humans, it’s not all that surprising that during the past few months I’ve received numerous emails and in-person queries asking about how dogs respond to humans’ hidden faces. I continue to say I really have no idea and that we need to be very careful about sweeping generalizations because there are large individual differences in personalities among our canine companions. There also are large differences in the relationships of dogs and their human(s) that might influence how the dogs respond to other people, masked or not.
While there are a number of essays dealing with the general topic of how dogs might respond to hidden faces showing only humans’ eyes and how to train them when they’re in these situations, I couldn’t find any data focusing on individual dog’s responses to masked humans.
Six weeks ago I decided to do some citizen science and gather information from people accompanied by dogs walking down the streets of Boulder (Colorado), sitting outside of coffee shops, and hanging out at a dog park. I always wore a face covering. On a few occasions when cycling through Boulder I stopped and talked with people who were with a dog. I asked them all how their dogs responded to masked humans who they knew and didn’t know and took note of how they interacted with me. I also asked them about their dog’s personality and general disposition concerning encounters with humans. I learned a lot and here’s a brief summary
First, there were no differences in the responses in different locations, so I combined the information. Of the 100 people and dogs for whom I got enough information, 74 said they noticed slight to large differences in their dogs when seeing a masked human, while 17 said they didn’t note any changes and 9 weren’t sure. In general, the differences in dogs’ responses included their being more hesitant to approach a human, more staring at them and inspecting them, and more sniffing the air. This all makes sense because dogs often use information from different senses—a cocktail of sensory input called a composite signal to assess who’s there, what they’re doing, and how they’re feeling—with other dogs, other nonhumans, and humans.
When I asked the people if they saw any differences when their dog encountered familiar versus unfamiliar humans, of the 91 who noticed or didn’t notice differences when their dog encountered a masked human, 77 (84.6%) thought familiarity was important, whereas 14 didn’t. I asked them to say more about the importance of familiarity and here are five responses.
“Joanne seemed to pay a lot of attention to the masked human’s gait, posture, and voice when she was approached. As soon as she heard a familiar voice, she loosened up.”
“Henry stared more at the person and when he saw or heard it was someone he knew, he wagged his tail and either approached them or allowed them to approach him. I think voice was important, but so was walking style.”
“I’m not sure, but Geraldine seemed to want to know more about the person and cocked her head as if she was trying to get a good visual and smell lead about who they were, and when she heard a familiar voice she loosened up and approached the human or allowed them to approach her.”
“Igor was more hesitant to approach all masked humans or to allow them to approach him, but somehow—and I have no idea how he did it—he made rapid assessments of whether he knew them and when he decided he knew them he would allow them to approach and pet him.”
“Millie, who I think of as being a visual and nosed dog, paid a lot of attention to how the person moved. She seemed to know how her human friends moved and that was the major cue for allowing them to approach her or for her to approach them.”
Many of the other descriptions were similar, all indicating that familiarity was assessed using different cues by different dogs. I couldn’t decipher any general trends and this made it clear that it’s important to be careful about sweeping generalizations about how dogs respond to masked humans. I also couldn’t tease out any differences among breeds or mixes, and gender and size didn’t seem to make any differences either. When I saw some of the people again, most said their dogs were “doing better” with masked humans. Tom told me it seemed that for his dog, Gino, “It had become business as usual.”
In addition to the above information, I also used myself as a confederate on 20 occasions. I simply put on a mask or a bandanna and approached 10 dogs who knew me and 10 who didn’t and approached them only after asking their humans if it was okay to do so. The 10 dogs who I knew and who knew me were slightly cautious when they saw me at a distance, but when I slowly walked toward them and said “Hello,” they instantly knew it was me. Perhaps they were using sound and visual information, but my impression was that voice was more important than gait and they knew something like I was the guy who always said, “Hello” and “How are you doing?” Sometimes a quick cocking of their head seemed to indicate they were pondering something like, “Hmmm, I think I know you, but I’m not sure.”
When I slowly approached the 10 unfamiliar dogs, six didn’t seem to mind at all, while four were hesitant and stared at me and cocked their heads from side to side, ostensibly trying to figure out who I was and what I was up to. Two of the four dogs were slow to let me get very close, and two stood firmly between their human and me. I slowly backed up and then asked the humans whether their dogs’ responses were typical of how they respond to unfamiliar humans. All said “Yes,” and didn’t think that the mask really made much of a difference.
Where to from here? The importance of citizen science for future research
These pilot data—and I fully realize that’s what these numbers really are—clearly show there are marked individual differences among our canine companions and how they respond to hidden faces, some dogs being more open to masked humans and others being more cautious. There are no “one-size-fits-all” explanations even for a single dog. So, it’s essential to avoid statements such as, “Dogs do this or that when they meet humans whose faces are covered up.” Clearly, and it’s no surprise, dogs use different signals or sets of signals to read humans and composite signals containing visual, auditory, and olfactory information often tell them what’s happening.
The omnipresence of masked humans provides opportunities for numerous people to do some research about their and other’s canine companions. Citizen science can help us learn more about how dogs respond to hidden faces and I hope the information I collected will generate more of these sorts of studies and also lay the groundwork for more systematic research. Another effect of the pandemic is the call for social distancing.1
It’s not only important to study the reactions of the dogs themselves. It’s also possible differences in humans’ reactions and the relationships they have with their canine companion’s influence on how their dogs respond. For example, do “helicopter humans” who say things like “Don’t do that” or “No!” cause their dogs to be more hesitant to approach humans in general, including those who are masked?
There’s still a lot to learn about our canine companions who live in different niches, ranging from homes to situations where they’re pretty much on their own. The same is true for companion cats who focus on human eyes. It’ll be interesting to learn more about how dogs and cats process available facial information and individual identity when only humans’ eyes are available for scrutiny.
Masked humans may be around longer than many want to believe, and understanding how your dog or cat responds to hidden faces can be fun and also help you learn more about their unique personalities. The more you know about them and the more they know about you, the better you’ll understand and appreciate them for who they are and the better they’ll understand and appreciate you for who you are, and this will be a win-win for all.
Note 1: When I asked my friend Heather McWilliams Mierzejewski about how her dogs responded to masked humans, she said it didn’t seem to make much of a difference and also mentioned possible effects of social distancing. She told me her dog Zoey learned not to approach humans, although before the pandemic she always wanted to say “Hi” to everyone. I hadn’t thought of the effects of social distancing, so that’s another idea for further study.
Bekoff, Marc. Dogs Watch Us Carefully and Read Our Faces Very Well. (Research shows dogs pay close attention to different human facial expressions.)
_____. How a Dog’s Brain Processes Human Faces. (New research using fMRI shows the bilateral temporal cortex plays a key role.)
_____. Dogs and Cats: Their Brains, Faces, Blinking Eyes, and Us. (New research clarifies various aspects of how dogs and cats communicate with us.)
_____. For Dogs, Helicopter Humans Don’t Balance Scolds and Praise. (Preliminary data show we say “no” or “don’t” far more than “yes” or “good dog.”)
_____. Canine Confidential: Why Dogs Do What They Do. University of Chicago Press, 2018.
_____ and Jessica Pierce. Unleashing Your Dog: A Field Guide to Giving Your Canine Companion the Best Life Possible. New World Library, 2019.
Flaim, Denise. Mask Force: Training Dogs to be Comfortable Around People in Face Masks. American Kennel Club, May 6, 2020.
Sándor, Krisztina and Ádám Miklósi. How to Report Anecdotal Observations? A New Approach Based on a Lesson From “Puffin Tool Use”. Frontiers in Psychology, 2020.
Stewart, Laughlin, Evan L. MacLean, David Ivy, Vanessa Woods, Eliot Cohen, Kerri Rodriguez, Matthew McIntyre, et al. Citizen Science as a New Tool in Dog Cognition Research. PLOS One, vol. 10, no. 9 (2015).
Sung, Wailani. How Can a Face Mask Affect Your Interactions with Animals? San Francisco ASPCA,
Our Pets and those Strange Masked People. My Pet’s Teacher, April 24, 2020. (A discussion about desensitizing dogs to face masks)
How to Train a Dog to be Comfortable With Face Masks. Health and Nutrition Lifestyle, May 13, 2020.