The Mouse's Tell

April 5, 2020 12:04 AM

Mice have a range of facial expressions, researchers find — Whether it is screwing up your face when sucking a lemon, or smiling while sitting in the sun, humans have a range of facial expressions that reflect how they feel. Now, researchers say, they have found mice do too. “Mice exhibit facial expressions that are specific to the underlying emotions,” said Dr Nadine Gogolla, co-author of the research from Max Planck Institute of Neurobiology. She said the findings were important, as they offer researchers new ways to measure the intensity of emotional responses, which could help them probe how emotions arise in the brain. What’s more, she said, the findings show mice have a repertoire of emotions.
posted by cenoxo (14 comments total)

Are there any mammals that don't do this?

Like, I understand that's not really how science works. But still. We may misinterpret their expressions, but I don't think I've interacted with any mammals that don't exhibit body language in some way or another.
posted by snuffleupagus at 12:23 AM on April 5, 2020 [10 favorites]

Sniff and Scurry revisited.
posted by fairmettle at 2:38 AM on April 5, 2020

(Theme song): When the wolf’s at the door, where is is Mighty Mouse when we need him?
posted by cenoxo at 5:53 AM on April 5, 2020 [1 favorite]

I bet sheep have a bunch of different subtle facial expressions, since they recognize and remember zillions of sheep faces.

Facial characteristics are also very important for wasps, and they also discern many individuals that way, though I wonder if the research could be effectively adapted to study them.
posted by SaltySalticid at 6:02 AM on April 5, 2020 [6 favorites]

Of course, mice have different expressions (e.g., contentment, distress and fear etc.) It upsets me that scientists not only thought that this wasn't so but even more so that they're willing to torture these animals to validate it and then offer some lame excuse that it's important to do this to understand how emotions arise in the brain. I think enough science has been done on this topic.
posted by SA456 at 8:01 AM on April 5, 2020 [9 favorites]

It upsets me that scientists not only thought that this wasn't so but even more so that they're willing to torture these animals to validate it and then offer some lame excuse that it's important to do this to understand how emotions arise in the brain

The rationale for doing this is probably less "we think mice don't have emotions" and more, I suspect, "how can we build a tool to recognize mouse emotions at a large scale using as little human labor as possible and with as much replicability as possible?" I can see, for example, uses for this thing to try and test the effects of anti-depressant medications on a wide scale with more naturalistic ranges of emotional state than our current tests. (Those current tests of anti-depressant meds are also much harder on the animals; studying how to create pain relief... necessitates pain.)

It's worth noting that nowhere in this article do I see the researchers discussing whether other mice attend to these facial expressions and respond to them. For some reason, I had a hell of a time getting to the original study, which is here. When I look at this original study, I find the same thing: these researchers want to do this work so that an observing human or machine-learning algorithm can quickly assess mouse emotional state, not because they are curious about social behavior among the mice themselves. (This is pretty common for model system work in neuroscience, although it drives me a little nuts.)
posted by sciatrix at 8:31 AM on April 5, 2020 [7 favorites]

Let’s please not make up torture accusations just because we don’t understand the methods, motivation, or goals of this research.

If you have a specific ethics violation to report please do so, otherwise “eww this is torture” sounds like an ignorant derail.
posted by SaltySalticid at 9:27 AM on April 5, 2020 [7 favorites]

Yeah, I don't think the question was "Do mice have emotions, or are they just unfeeling automatons?" I think the (basic) question was, "Can we delineate between specific emotional states in mice by observing their facial expressions?"
posted by Saxon Kane at 10:51 AM on April 5, 2020

SaltySalticid - Although they're not social like wasps, can jumping spiders (with their excellent vision) discriminate between individuals in their own species?
posted by cenoxo at 11:16 AM on April 5, 2020

I wouldn’t think it comes up much; they’d generally see conspecifics only rarely, and that’s for mating or maybe prey.

Their vision is incredibly well studied though. Here’s work showing that a Portia species uses visual information to distinguish salticid prey from non-salticid prey, using the big ol’ ante-meridinal eyes as the cue. They have a whole host of behaviors that they only use when stalking salticids, that’s part of how we can tell they made an ID :)
posted by SaltySalticid at 11:48 AM on April 5, 2020 [5 favorites]

I saw some incredibly neat work in peacock spiders by Sebastian Echeverri on female preference in visual signals at this year's Society for Comparative and Integrative Biology meeting back in January, too. Really fine-tuned stuff, and he was able to follow both the spider's gaze and the visual preference of the spider by handing a spider temporarily hanging from a pin a little marked styrofoam ball to hold and "walk" on, through which he could calculate the direction she was intending to walk in.

Re: facial expressions in sheep, I find the ability of sheep to distinguish between the faces of individual sheep and humans really fascinating. I do have to wonder how much sheep rely on vision to work out individual identity in a herd, though. I don't think sheep primarily use focused visual signaling, their eyes are designed for relatively motion-sensitive but "blurry" vision, sheep don't have a lot of visual distinctiveness in the face, and sheep have excellent olfactory signaling that seems like a much better potential option for identity signaling. There's also a huge difference between facial recognition and facial signaling of emotional states or communication, and I really doubt sheep are using those types of signals. Sheep have relatively minimal facial musculature and control compared to a primate or even a rodent, and I cannot think of any sheep body language that's restricted to a facial posture or movement--although I'm very much not a sheep expert. Maybe flehmen? But that's largely about olfactory signaling...

On the other hand, dogs use consistent enough facial signaling that humans read them reliably even if they're relatively inexperienced with dogs and exaggerate the strength of their facial expressions when humans are paying attention. Dogs and other carnivores also have facial markings that makes facial expressions easier to see at a distance--think about a wolf's face, or about how many dogs have patterns of tan or black highlighting the eyes and mouth. The same is true of many cat species and other kinds of carnivores, like mongoose.

Mice are somewhere in between the two extremes of sheep and dogs in this case; mice don't have facial markings designed to highlight facial expressions, but they also have much more control over their facial muscles than sheep do. It's worth noting that many of these facial expressions in the mice seem to be about the posture of the whiskers and the ears, which are highly mobile on a rodent and are under very fine levels of control. I'd be really interested to see if the mice themselves can recognize these distinctions and use them in social decisions, although I'm not sure how I would personally design an experiment to test that.
posted by sciatrix at 1:48 PM on April 5, 2020 [4 favorites]

Well, of course they do!!
posted by KleenexMakesaVeryGoodHat at 2:19 PM on April 5, 2020

BRB teaching my mice not to chase an inside straight, or go hard with a flush draw on the table
posted by Fiasco da Gama at 6:00 PM on April 5, 2020 [1 favorite]

Mice playing poker (gallery): love the CEE-gar.
posted by cenoxo at 8:10 AM on April 6, 2020 [1 favorite]