(A followup to Cats, Dogs, Strings, and Causality. Cross-posted to Felines Are Wonderful)

My post referencing the 2009 cat-cognition study noted that:

(a) Most of the popular articles regarding that study made what looked to me like unwarranted interpretive leaps (sadly not much of a surprise there these days), and

(b) While the study itself read as more “neutrally investigative” and data-focused than the popular articles, it did not seem as if the experimental setup necessarily accounted for feline sensory modalities, and hence may not have permitted a true test of the cats’ cognitive capacities in the area of physical causality.

So, in light of item (b) above, and in light of the fact that I had all the necessary components on hand to create a setup similar to that used in the aforementioned study, I decided to see if my own feline housemates might be interested in trying their hand (or rather, paw) at some string-pulling.

Of course I am not aiming to present my own “results” as Real Scientific Data; they were, after all, quite informally obtained from a tiny sample set. At the absolute most, observations presented herein might represent a sort of “proof of concept”, i.e., how setups could be improved in future experiments to increase the likelihood of meaningful results. Overall, though, I mainly did this for fun — for me, and for the cats!

BACKGROUND

Four cats were offered the opportunity to participate in this activity:

(1) Brodie
DOB: 15 August, 2009 (approx)
SEX: Male (neutered)
ANCESTRY: Domestic shorthair

(2) Coraline
DOB: 15 August, 2009 (approx)
SEX: Female (spayed)
ANCESTRY: Domestic shorthair

(3) Shadow
DOB: 15 August, 2009 (approx)
SEX: Male (neutered)
ANCESTRY: Domestic shorthair

(4) Nikki
DOB: 28 October, 2001
SEX: Female (spayed)
ANCESTRY: Siamese (Chocolate Point)

The three younger cats (Coraline, Brodie, and Shadow) were littermates, born into a feral colony. I adopted them when they were between 7 and 10 weeks of age. The elder cat (Nikki) is unrelated to the others, was born into a cattery, and lived with my parents until early 2010.

All four cats had lived with me for at least six months prior to the experiment, and since the experiment took place in my’ home, they did not have to acclimate to an unfamiliar environment beforehand.

PREDICTIONS

Predictions going into the experiment were as follows:

(1) At least one cat (of the four) would demonstrate both motivation and ability to complete at least one task case successfully.

(2) Performance (in motivated cats) would improve when the treats were made more visually obvious, i.e., via use of color and size contrast.

(3) Performance might improve if a less flexible medium (i.e., plastic zip ties rather than string) was used, as this would provide faster feedback to the cats regarding their efforts and would be less likely to induce distraction (cats often find strings, and their movements, extremely interesting in their own right).

SETUP

The setup used in this exercise was based on the description provided by the study¹:

The apparatus consisted of a box of base size 49 × 40 cm with clear Perspex walls on three sides and a wire mesh lid. The top of the box hinged off the base to allow access to the inside. The base was made of chipboard with a white plastic surface, and protruded from the box at the front by 9 cm, providing a smooth surface and good contrast for the strings. A 1-cm gap at the base of the front wall allowed the strings to pass from the front accessible end into the inaccessible part of the box. A clear Perspex bridge (base size 11 cm × 6 cm) was used in trials where there are two crossed strings to prevent the strings getting tangled. Every part of the set-up was visible to the cats at any time. The strings were blue rope (∅ 5 mm), with a length of 25 cm (long) and 10 cm (short). Cat treats were attached to the strings to act as rewards for succeeding in the task. The reward for each trial was approximately 10 g of mashed tuna or pilchards, or a small cat biscuit.

Some articles referencing the study also included a photograph of the apparatus used, which I attempted to replicate as closely as possible given available materials.

Main Structure

To make the main structure of the apparatus, I used several pieces of scrap, held together with blue painter’s tape in a rectangular “frame” shape. To the bottom side of the frame I attached a sheet of thick white watercolor paper.

To the top side of the frame I attached a piece of Plexiglas with a grid pattern drawn on it — however, upon closer reading of the study apparatus description (after I’d already completed my experiment), I noted that the original study had used a plain wire mesh on the top of the frame.

(Image showing main structure of test apparatus I built)

This meant that, contrary to my original (incorrect) impression, the cats more than likely would have indeed been able to smell the treats, as wire mesh blocked their physical access to the treats via the top of the box, but not the transmission of odors. If I were to try the experiment again at home I would use a piece of window screen or similar material for the lid of the box, rather than Plexiglas.

Another difference (albeit a deliberate one in this instance) between my setup and the referenced study’s setup was the fact that in some trials I employed a central wooden divider that extended the interior length of the box (parallel to its left and right sides).

The purpose of this divider was to prevent the strings or zip tie mechanisms (more on that in a moment) from interfering with each other physically at all during “parallel string” trials, as I saw the potential for distraction if one string ended up touching the other while the cat was pulling on it, etc. However, in practice this divider turned out to be unnecessary, as when I removed it the cats’ performance did not change and the strings/zip ties did not get tangled at all.

Treat Delivery Media

I experimented with two primary variables in terms of the treat-delivery media:

(1) Flexibility: In some trials I used actual strings (lengths of very flexible sisal twine), with or without a “treat container” at one end (see below):

In others I used plastic zip ties modified to include a small “cup” on one end to hold treats.

(Image shows one of the zip tie/treat cup mechanisms employed)

(2) Contrast: In the first few trials I used unmodified sisal twine lengths and simply tied a piece of dry cat food or chicken jerky to the end of the treat-carrying piece (see image below, note the lack of visual contrast):

In the second few trials I used yellow “cups” filled with a small amount of dry cat food attached to the ends of plastic zip ties.

In the third round of trials I went back to using the sisal twine, but attached the end of a white plastic spoon as a treat container.

The goal here was to see what, if any, impact visual contrast had on the cats’ ability to correctly identify the treat-carrying piece (thus distinguishing it from the “dummy” piece). One major criticism I had of the original study was that (inasmuch as I could tell from the description and photos available) it did not seem as if the treats were sufficiently visible to the cats.

Since, as I noted in my prior post, cats have fairly poor close-range visual acuity for fine details, I surmised that the treat holder needed to be significantly larger/wider than the end of the string (or zip tie) in order for them to be able to distinguish it properly. I also figured that it would be helpful for the treats themselves to stand out color-wise against the background of their container or cup.

TRAINING

I did not employ a formal “training phase” as the study described doing. However, I did present the treat-delivering string and zip tie pieces to the cats for inspection (prior to inserting them into the puzzle box). During this activity some of the string/zip tie pieces contained treats and some did not.

I also left the apparatus on the floor for several hours prior to starting any task trials, so that the cats would be able to investigate it at their leisure and not be distracted by the sheer novelty of the equipment when the task trials began.

RESULTS & DISCUSSION

Participation Variation

Of the four individual cats presented with the test equipment, two (Coraline and Brodie) completed various task cases successfully. Shadow was very interested in watching his siblings but declined to participate himself, and Nikki seemed totally uninterested in the activity.

Having lived with these particular cats for some time now I am not surprised by this outcome, given their respective personalities and predilections; Coraline and Brodie (Coraline especially) have always been the most mechanically inclined of the group, whereas Shadow is more inclined to solicit favors from humans (i.e., he’d rather meow at me to GIVE him a treat than try and get one himself).

Nikki, meanwhile, just tends to operate on an agenda all her own, and while at some point I can see her getting interested in a string puzzle of some sort, she wasn’t interested on the day(s) on which I ran trials.

I should note that I do not draw any conclusions (negative or positive) about the non-participant cats’ understanding of physical cause and effect based on their non-participation in this particular exercise. Since neither of the non-participants even attempted to complete the task, all I figure is warranted in terms of conclusion is that the materials and situation failed to inspire their interest, which of course says absolutely nothing about their capacity to cogitate about string and its uses.

Social Factors

By “social factors” here I refer to the presence/absence of multiple cats near the apparatus setup during task trials. Initially I tried testing one cat at a time, however, for the younger cats this proved impossible. No single cat would participate or do anything with the apparatus at all when separated (via a closed door in the house) from his or her siblings. Instead, the lone cat would wander around looking for his/her siblings, while the sibling cats would scratch at the door.

Once I let all the cats wander about freely, though, the three younger ones were plenty interested in the apparatus and two of them participated consistently over the course of three days. To me this suggests social factors might be more important to cats (especially related cats who get along well) than many would necessarily suspect. Having all the cats accessing the setup simultaneously did make certain aspects of the experiment more difficult to organize but it was certainly a better situation than zero participation, as I had when I attempted to test a single lone cat at a time.

As for Nikki’s non-interest in the setup, social factors may have played a role her as well — she tolerates the others but does not seem to like being very near them. I may try taking the apparatus out to the patio at some point and seeing if she might show more interest there — she seems to be a lot more inhibited indoors, will only play with toys in the yard, etc.

Basic Observations

Again, as this was an informal/fun exercise and not an Official Scientific Experiment, I did not keep a precise count of how many times a given cat solved a task — since I was the sole person setting up and running everything, it was not possible to carefully track every variable. However, I did note whenever a cat was able to solve a particular task case 2 or more times, and I considered that to be my basis for “success”.

As expected, none of the cats completed a task in which a treat was tied to the end of a string. They all seemed vaguely interested in the strings as strings, but did not appear to even realize that one of them had a treat attached. I expect that this effect was compounded to a degree not necessarily present in the referenced study due to my use of plexiglas rather than wire mesh (which they’d have been able to smell the treats through) as a box lid. Unfortunately I did not get any video footage of this phase.

During the zip tie trials, Brodie and Coraline both consistently solved the parallel case. Their success was independent of “position habit”, meaning that I was able to switch what side the treats were on and/or move the apparatus to a different room in the house and they still knew what zip tie to pull on to get the treats.

Brodie solving parallel zip tie task (room #1, treats on left side):

Brodie solving parallel zip tie task (room #2, treats on right side):

Cora demonstrates her zip tie prowess here:

(This one is actually an “amusing out-take” candidate — I had not yet properly secured the apparatus to the floor before this trial, and Cora got her claw stuck in the treat container after she pulled it out, so we had a bit of a treat explosion! Her brothers, of course, were pleased by this turn of events.)

I did not end up doing a “crossed” case with the zip ties, because I discovered that the ties were too thick to fit under the 1 cm gap at the front of the box when stacked on top of one another. Refinement of this task would definitely account for this issue.

In the “string and spoon” phase (in which the treats were placed into the end of a white plastic spoon attached to one of the pieces of sisal twine), again, both Coraline and Brodie were successful at the parallel strings task. Unfortunately (due to disorganization and logistical wrangling difficulties on my part) I did not get a video of Brodie doing this but I got two of Coraline:

In the “crossed strings” case, Coraline had no trouble with this at all. I don’t think she went for the “wrong” string even once. Brodie did not do as well here, however, he has always been very interested in string as a toy, and it seemed like when the strings were crossed it was a lot more fun to play with them than try to figure out which one had a treat attached to it.

The video below shows Cora easily solving the crossed-strings case:

(To me it certainly LOOKS like she knows darn well what the function of the string is, but I am not sure how to quantify this observation!)

CONCLUSION

In conclusion I note that my predictions (1) and (2) turned out to be accurate inasmuch as I could tell. Two out of four cats-in-residence completed at least two types of task each, which to me suggests that their performance was unlikely to have been the result of “random luck”. However, of course in a formal study many more data points would be taken and results might differ.

As for the contrast issue, while again more data would be a good thing to have here, it really did seem based on what I observed that if the cats could clearly see the treats, those motivated to obtain them had no trouble doing so.

As for whether the zip tie mechanism improved performance (due to it being easier to physically manipulate than the string), it did look like this was probably the case, at least for the parallel task. Again, physical constraints of the apparatus prevented me from trying a true “crossed zip tie” case.

Finally, I find myself really wishing there were some way to quantify or better express what looks to me like “purposefulness” in Cora’s performance on the crossed strings task. Perhaps, though, the difficulty of quantifying such impressions is why well-designed experiments employ numerous trials through which many data points are obtained, so that one is not relying upon subjective impressions, but rather, probability.

And all that said, I do have to say that trying this experiment (fumbling as my attempt was…) definitely turned out to be highly enjoyable, both for me and for the participating (and spectator) cats. I’ve since been strongly inspired to come up with ways of feeding them more creative than just dumping food in a bowl, as they seem to greatly enjoy “outsmarting” their food, which I suppose is quite appropriate for a small carnivorous predator species!

Existence is Wonderful

(A sort-of followup to Cats, Dogs, Strings, and Causality and A Small, Informal Cat Cognition Experiment)

Today I tried looking up studies and/or scholarly articles on the phenomenon of Cats Knocking Things Over, but didn’t come up with any interesting results. The majority of writing on this subject seems to be in the context of advice on “cat behavior problems”, e.g., Dealing With Cats That Knock Things Down, How can I get my cat to stop knocking stuff over?, etc.

(Of course, if anyone has any links to papers on this subject please feel free to share!)

But anyway. It occurred to me, upon seeing Shadow (one of three ex-feral littermates sharing my home) push a container of cat treats off my desk for the nth time earlier today, that (if it was indeed being done deliberately) such an action might represent a fairly well-developed understanding of certain physical principles. I.e., the fact that if one cannot readily access the contents of a treat-containing object, one might be able to gain access via utilizing the tendency of objects to fall over when pushed or similarly manipulated.

(Full disclosure: as a person on the autistic spectrum who is also interested in neuroscience and relevant cognitive research, I must admit it tends to catch my attention whenever I encounter what to me looks like an interesting ability or trait, in any species, being largely written off as a “behavior problem”. Often it seems to me something is being missed when this occurs, so I’m driven to investigate in situations like this!)

Certainly the standard “I am not a professional researcher, this was all done completely informally, my home is not a laboratory, etc.” disclaimer must be applied to these results. Moreover, I am well aware that interpretation is not data (and vice versa), and in truth the only thing that can be said for sure is that at least one of my cats pretty consistently knocks over objects when is is conceivable that he has reason to believe these objects could contain treats.

The following three videos appear in chronological order. All were filmed on 5 September 2010, in the afternoon, within the space of maybe twenty minutes.

In this first video (”Cats and Gravity I”), Shadow is shown pushing a sealed container of treats off my desk.

He had precedent for doing this, as this particular container is the usual one I put the kitties’ daily allotment of treats in. Once, about a week ago, I left the lid part-way off, to see what he would do (seeing as he’d definitely be able to smell the treats within). And in that case he proceeded to nudge the container around with his nose until it fell off the table, scattering treats hither and thither, much to his and his siblings’ delight.

Now, I am fairly certain that this first knockdown was an accident. However, since then, Shadow has pushed the treat container off multiple other surfaces (besides the coffee table), on multiple separate occasions. “Cats and Gravity I”, then, seems like it could very well represent Shadow’s having learned that “if I push this container, sometimes treats fall out!” I don’t know that anyone in the cognitive research field actually believes this level of reasoning is beyond the domestic feline (I suspect not) but in any event, it makes for a good “baseline” data point in terms of the variables I am interested in observing.

In this next video (”Cats and Gravity II”), we have an interesting situation involving three cats. You may remember Coraline and Brodie from all those string and zip-tie trials I ran as a rough check of what experimental design conditions might be improved so that cats could better demonstrate their actual cognitive capacities in string-pulling tasks. In the case of that set of puzzles, Cora and Brodie were the only participating felines; Shadow preferred to simply watch.

However, in “Cats and Gravity II”, you will observe that Brodie “experiments” with the treat-containing bottle but doesn’t succeed in getting anything out of it, whereas Shadow makes one single decisive swipe and sends the thing crashing down. Note that this bottle is different from the treat container in the first video, but it is one that I’ve put treats in several times prior to this, so the cats would definitely be familiar with it.

(Coraline, meanwhile, is ignoring the whole business and seems more excited about the fact that I’ve gotten up from my computer chair, giving her an opening to steal it. To me this mainly suggests that at different points in time, different cats may have very different priorities!)

And then we come to “Cats and Gravity III”. The outcome of this scenario completely caught me off guard (you may even be able to hear me exclaim “HOLY CRAP!” at one point). In this case I took a treat container that would be new to all the cats (another empty vitamin bottle, this time a dark purple one slightly larger than the white one used in “Cats and Gravity II”). I let them watch me putting treats into it, and then placed this bottle on top of a small end table in the living room (a different surface in a different part of the house than my desk, to control for position habit).

In this case, the video shows that initially none of the cats really showed interest in the new treat bottle when I first placed it on the end table. However, after I went over and shook it a bit, Shadow went over to the table, put his front paws on the top surface, and then proceeded to lift the bottle up with his mouth and throw it down onto the floor. (That’s where I exclaimed “HOLY CRAP!”, by the way.)

So…what to make of this?

Subjectively speaking (yes, I’m about to offer an interpretation), it looked to me like Shadow spontaneously came up with a really creative way of getting the treats he knew were inside the purple bottle. Which would suggest that he’s learned to generalize beyond “if I paw at this maybe it will fall and treats will come out” and now understands that it is not the mechanical motion of pawing or nosing that’s important, but rather, the falling of the bottle itself, if one’s goal is to get the treats out of the bottle. This, to me, seems pretty significant, and again I’m curious to know if there’s any literature out there saying one thing or another about this type of cognition in felines.

However, this was of course a tiny sample set. And I did not do this series of “mini-trials” in response to another study I’d be able to cite and/or comment on — like I said at the beginning, I couldn’t find any studies about cats knocking stuff over. No peer-reviewed references = not “ResearchBlogging”. Plus, for all I know, cats’ understanding of gravitational cause-and-effect is already well documented and known and I just fail at searching for this documentation.

That said, at the very least, I think anyone who really wants to study cats’ understanding of cause-and-effect as it pertains to objects in a broader sense would do well to try out a variety of different scenarios involving different types of objects, and requiring different types of attentiveness and planning on the cats’ part.

I find it terribly problematic (and this goes back to my discussion of the string experiments again) when a single particular test is taken (whether by the study authors, the media, or both) as meaning something globally significant about a given population’s abilities or lack thereof. In the absence of a single task (or task type) with huge amounts of existing data backing up its ability to test “general” cognitive ability in a given domain, multiple tasks of varying attributes would seem to me required for appropriate levels of rigor.

Also, I have to say that another reason I wanted to post these videos is because now more than ever I am beginning to think it is very important to have as much of an experiment on record (for multiple parties to view and evaluate) as possible. Even though I (hopefully) disclaimered the heck out of my string experiments, I still would rather do things as close to “right” as possible for a layperson — just because I’m not a real researcher doesn’t mean I can’t practice holding my informal stuff to higher standards.

Finally, I would just like to say that I would be extremely interested to get people’s comments on what it looks like is actually happening in the videos above. As in, if you think Shadow is doing what he’s doing deliberately, what aspects of his actions lead you to think that? I’m curious about this because I see my cats doing all sorts of things all the time, some of which (to me) look “deliberate”, whereas other things they do look thoroughly “accidental”. Only I haven’t come up with a good way to describe what “deliberateness” looks like in quantitative terms.

I suspect that in general this sort of issue comes up a lot in animal cognition research, which has me curious as to whether there even exists any kind of objective way to measure something so “internal”. Behaviorism (in my opinion) fails miserably to account for everything that could potentially be important (for one thing it often seems to completely fail to account for, say, different sensory and perceptual modalities on the part of the researcher vs. subject), and much of what I hear from “evolutionary psychology” sounds like it’s been pulled straight from someone’s nether orifice, to put it politely. So I’d be really intrigued to know what other tools or paradigms may currently be out there that might be more promising.

Existence is Wonderful

The senses of smell and taste are termed chemical senses because they detect chemical stimuli and encode chemosensory information into neural signals. A variety of diagnostic terms have been used to describe smell and taste disorders. Standard classification terms for olfactory disorders are anosmia (absence of smell), hyposmia (diminished sensitivity of smell), and dysosmia (distortion of normal smell). Phantosmia, a type of dysosmia, refers to perception odor in absence of an odor stimulus, and parosmia refers to distortion of odor perception when an odor is present. For taste, diagnostic terms include ageusia (absence of taste), hypogeusia (diminished sensitivity of taste), and dysgeusia (distortion of normal taste). (more…)