Integrating Living Organisms in Devices to Implement
Care-based Interactions
Jasmine Lu

Pedro Lopes

University of Chicago
jasminelu@uchicago.edu

University of Chicago
pedrolopes@uchicago.edu

Figure 1: We explore how embedding a living organism, as a functional component of a device, changes the user-device
relationship. In our concept, the user is responsible for providing an environment that the organism can thrive in by caring forthe organism. We instantiated this concept as a slime mold integrated smartwatch. The slime mold grows to form an electricalwire that enables a heart rate sensor. The availability of the sensing depends on the slime mold’s growth, which the user
encourages through care. If the user does not care for the slime mold, it enters a dormant stage and is not conductive. The users
can resuscitate it by resuming care.

ABSTRACT
Researchers have been exploring how incorporating care-based
interactions can change the user’s attitude & relationship towards
an interactive device. This is typically achieved through virtual
care where users care for digital entities. In this paper, we explore
this concept further by investigating how physical care for a livingorganism, embedded as a functional component of an interactive
device, also changes user-device relationships. Living organisms
differ as they require an environment conducive to life, which inour concept, the user is responsible for providing by caring for theorganism (e.g., feeding it). We instantiated our concept by engineering a smartwatch that includes a slime mold that physicallyconducts power to a heart rate sensor inside the device, acting as aliving wire. In this smartwatch, the availability of heart-rate sensing
depends on the health of the slime mold—with the user’s care, theslime mold becomes conductive and enables the sensor; conversely,
without care, the slime mold dries and disables the sensor (resuming care resuscitates the slime mold). To explore how our living
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https://doi.org/10.1145/3526113.3545629

device was perceived by users, we conducted a study where participants wore our slime mold-integrated smartwatch for 9-14 days.
We found that participants felt a sense of responsibility, developed areciprocal relationship, and experienced the organism’s growth as asource of affect. Finally, to allow engineers and designers to expand
on our work, we abstract our findings into a set of technical anddesign recommendations when engineering an interactive device
that incorporates this type of care-based relationship.

CCS CONCEPTS• Human-centered computing → Human computer interaction(HCI); Interaction devices.

KEYWORDS
Living organism, caring interaction design, slime mold, symbiosis
ACM Reference Format:
Jasmine Lu and Pedro Lopes. 2022. Integrating Living Organisms in Devices
to Implement Care-based Interactions. In The 35th Annual ACM Symposium
on User Interface Software and Technology (UIST ’22), October 29–November
02, 2022, Bend, OR, USA. ACM, New York, NY, USA, 13 pages. https://doi.
org/10.1145/3526113.3545629

1

INTRODUCTION

Interactive devices are designed to be easy-to-use, function fast, andact almost invisibly. These are key principles in Weiser’s ubiquitous
computing [70], which has driven decades of computing research

UIST ’22, October 29–November 02, 2022, Bend, OR, USAand products. This vision enabled seamless interactions by designing for “invisible” devices. While this is desirable and useful inmany ways, this invisibility is not without shortcomings. A striking
one is that it has the unfortunate side-effect of conditioning users
to see devices as distant entities or, even, conditions users to not
engage with the environmental implications of consumer devices[9, 34, 42, 43]. As new devices are released, millions of outdated
devices are thrown out in piles of e-waste—“a record 53.6 million
metric tonnes of electronic waste in 2019, up 21% in just five years”[25].
Many researchers, thinkers, and policy makers argue for a different relationship with our devices [6, 8, 10, 26, 36]. In the HCI
community, many have been exploring how to create alternative,
more caring relationships & attitudes in the hope that by changing
the relationship, users might connect more responsibly with theirdevices and thus extend their devices’ lifetimes [11, 39, 40]. Somepowerful examples include, incorporating care or maintenance aspart of the interaction [40]; embedding a user’s own personal histories with a device to promote keeping devices for longer periods[24, 55]; designing interactions to be slow and experienced overa long time [15, 56]; using animated materials to inspire a senseof aliveness [1, 7, 18, 20]; or integrating personalities in users’ devices to promote kinship with the device by anthropomorphizing
the devices [14, 16]. These approaches are similar in how they areattempting to make devices “appear more alive”.
Simulating liveliness, in many cases, still falls short. A key historical example of this interface design is the Tamagotchi, a popularinteractive device from the 90s in which users took care of a virtual
pet by feeding it and watching it grow [44]. While this interactive
device allowed users to develop caring attitudes, after the novelty ofthe experience wore off, most Tamagotchis were discarded [12, 58].
Ultimately, these virtual care-based devices offer potential (andhave many advantages that stem from their virtuality) but, just likethe Tamagotchi, these devices are constructed from inert materials,
which signal to the user that the care is virtual, making it harder tofeel empathy or responsibility [27, 49].
Instead, we propose & explore how integrating a living organism in the functionality of an interactive device changes therelationship. We achieve this by implementing a physical carebased interaction. Living organisms need an environment they can
thrive in. This makes them notably different from virtual organisms
or the inert materials that make up most interactive devices. In
our concept, the user is responsible for providing this favorable
environment by caring for the organism (through watering, feeding,etc.).
To explore this concept, we instantiated it in the form of a functional smartwatch, which includes a slime mold that powers a heart
rate sensor inside the device (our slime mold acts as a living wire, as
depicted in Figure 1). As such, the availability of heart rate sensing
is dependent on the health of the slime mold. If the user cares forit, it grows to become conductive and enables the sensor. On theother hand, if the user does not care for the slime mold, it dries up
and enters a dormant stage in which it is not conductive. The users
can resuscitate it by, again, resuming care.
To explore how this living artifact introduces new relations between human, device, and slime mold we conducted a study whereparticipants were asked to wear and care for the smartwatch andJasmine Lu and Pedro Lopes

physarum device for 9-14 days. During this period, participants
were asked to complete (1) a diary study where users reported
their daily experiences wearing and caring for the device; and (2)interviews mid-way through and at the end of the study. From thisstudy, we found participants felt a sense of responsibility towards
their device, developed a reciprocal relationship, and experienced
the organism’s growth as a source of affect. Last, by drawing fromour findings and process of engineering the care-based interactive device, we synthesized a set of recommendations for otherresearchers interested in building on our work.
Importantly, our goal is not to argue that technology must be
hybridized with living organisms or that they offer technical improvements compared to inert materials (in fact, we acknowledge
they have a range of disadvantages compared even to a simple
copper trace) but, instead, we focused on exploring the implicationsof this type of physicalized care-based interaction and how futureengineers and designers can center care in interactive devices.

2

RELATED WORK

Our work builds on top of interactive systems that explore alternative user-device relationships, such as explorations of slow technology or friction-based UIs. Our work is also inspired by existingcare-based interactions that use virtual care to explore and foster amore personal and responsible connection with interactive devices.
We also draw on previous approaches in collaborating with livingorganisms in the design of interactive devices. Finally, to give thereader the required background to replicate our technical implementation, we provide an overview of the slime mold organism
used in our prototypes with an emphasis on the unique properties that make them viable as a functional material for interactive
devices.

2.1

Alternative User-Device Relationships

Various HCI researchers have explored how we might foster alternative relationships and attitudes to our devices. Many achieved
this by creating interactions that are distinctly different from thefrictionless, invisible, fast, or productivity-oriented interactions
that pervade most all devices.
Hallnäs et. al [31] presented slow technology as “technology
aimed at reflection and moments of mental rest rather than efficiency in performance”, which has since been explored in HCI tocreate moments of reflection with interactive devices or a slower
temporality of interaction [15, 54]. Others have explored adding intentionally difficult to use interactions, making users reevaluate theway they normally engage with their devices. For instance, Crankthat Feed, explored how forcing users to scroll through their twitter
feed via a mechanical crank encouraged users to be more reflective
about their interactions with the device they used for social media
consumption [63]. Paulos and Pierce have proposed Counterfunctional Things as a design approach to intentionally create functional
limitations for digital devices, such as by creating a camera that has
to be smashed apart in order to access photographed images [60].
These approaches to reimagine our relationships to devices have
similarly been explored across critical design [23], ludic design [28],speculative design [13], and adversarial design [11]. In our work,
we are also interested in enabling reflective attitudes and relations

Integrating Living Organisms in Devices to Implement Care-based Interactions

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

to interactive devices and do so by redesigning a smartwatch torequire caring for a living organism.

2.2

Caring Interaction Design

Many users might feel little responsibility for their devices as theycan easily be replaced if broken or when a newer model comes out(which in many popular devices, like iPhones, is annually [73]). As
e-waste becomes a growing issue globally, one way HCI researchers
have focused on addressing this is by exploring how to foster caring
relationships between user and device [10]. In Proceed with Care,
Key et. al [39] explores how incorporating care ethics and thingcare
in reimagining interactive devices might enable a more inclusive
and responsible future of these technologies. Researchers have also
explored care that goes into repair, maintenance, and creative reuseof device materials [35, 48, 67]. Others in HCI have explored how
to enable caring interactions through the design of the interactive
devices, creating interactions that encourage users to see devices
as indeed, worthy of care. Oftentimes these designs involve formsof virtual care where users are meant to respond to qualities oflivingness in digital entities.
2.2.1 Adding Virtual Care to Interactive Devices. Across HCI, muchresearch has been devoted to developing highly useful applications
to encourage users to feel invested and attached to their devices.
These efforts are important in avoiding device obsolescence and,while these can also encompass a type of caring interaction, we areinterested in interactions designed specifically to encourage users
to feel responsible for their devices beyond their usefulness.
In interactive devices, this has primarily taken the form of virtual
pets that require users to perform some sort of “care” to sustain
them. The choice of a pet for these designs might appear inconsequential at first but it is effective and well-motivated in thathumans display more emotional and responsible attitudes for pets
than for inanimate objects [27, 46]. In this way, these devices alter
the relationship by using the virtual pet to attribute characteristics
generally seen only in a living animal or companion species to aninteractive device [22]. The most striking historical example of aninteractive device that included with a virtual pet is the Tamagotchi,
which allowed users to grow different virtual pets by deliveringvarious gamified forms of care [44, 58]. Outside of gaming and toys,these virtual pets or virtual companions have also been widely
explored across HCI as useful for learning [33], companionship[45, 69], medical interventions [52], and more [21].
In virtual pet/companion experiences, users feel responsible for
their interactive devices since caring for their virtual companion
is intertwined with the device use. However, there is a limit to theattachment formed between user and virtual companion. Ultimately,users will understand that these companions are virtual and made ofinert, inorganic materials that might feel easily disposable. Despite
the excitement around caring for Tamagotchis at their peak, a few
years later they became out of fashion and near obsolete, likely
trashed or relegated to the back of closets [58]. As explained in
Disposable Love: The rise and fall of virtual pets, “Tamagotchi is seen
as a symbol of its times in which even the most intense connections
are disposable” [12].

Figure 2: Images of Physarum polycephalum in the wild,
growing naturally, and in a petri dish growing on oats. (Images courtesy of Rich Hoyer, Helen Ginger, Carolina Biological).

2.3

Living Organisms in Interactive Devices

Recently many researchers, designers, and artists have been interested in exploring what new interactive capabilities can be enabled through living materials [29, 38, 41, 59, 62, 68]. This has been
primarily explored through Living Media Interfaces [51], which
incorporate living organisms in interactive designs. For instance,
Rafigh [32], Biogotchi [17], and recent work from Ofer et. al use
living organisms as visual displays [57]. Other devices, such as Nukabot [16] or Project Florence [64], emphasize digitizing biologicalsignals. By incorporating a living organism in their design, the careof and sustainability of the organism is inextricably involved too.
However, in most cases the care of these organisms is not integrated in the interactions with these devices—the care for the livingorganism is not intertwined with the interactive functionality ofthe device itself. While a living organism is much less stable thaninert materials (this is of course a major limitation using living
materials), it also presents an opportunity for new relations basedon care that might make users more considerate of the material
properties of our devices. As such, we are interested in emphasizing
the care work involved in integrating living organisms rather thanrelegating it to the background. In our example, we focus on care ofa slime mold (Physarum polycephalum), chosen due to its uniquebiological capabilities.
2.3.1 Physarum Polycephalum. Finally, to give the reader the background to replicate our technical implementation, we provide an
overview of the organism used in our prototype. Physarum polycephalum are single cell organisms known for their ability to growtowards food sources. While they can live as single cells, they often aggregate and propagate via growth and multinucleation, as
depicted in Figure 2. This organism belongs to the protist family,
distinct from fungi, plants, or animals. Scientists have studied themin a variety of contexts in the lab and in-the-wild. Due to theirresilience and bio-safety level 1 (i.e., not known to cause diseasein healthy adults and present minimal hazard), they are popularly
used in educational science experiments in classrooms [13]. Important to note is that, unlike many other organisms, physarum
polycephalum thrive well in non-sterile environments and feedfrom a variety of sources, even as simple as oat flakes and water.
Our interest in this organism as a material for interactive devices
is inspired by its unique biological properties, which have been
explored by researchers focused on engineering living circuitry,
namely Whiting et al. [71] and Adamatsky et al. [2]. We primarily

UIST ’22, October 29–November 02, 2022, Bend, OR, USAleverage two unique characteristics in our design: (1) physarum
are extremely effective in growing towards food sources [53]; and,(2) they can conduct electricity [4]. Moreover, (3) they also react toother external stimuli including light, heat, touch, and chemicals[50]. These unique properties have led many to explore physarum
as conductors [71] or as simple logic gates/sensors [2, 5, 72].
On top of the aforementioned technical reasons that makephysarum a viable organism to be directly integrated in the functionof an interactive device, we also designed around two additional
unique properties: (4) they can thrive in a wide range of environments as long as a certain level of humidity is maintained and foodis available [19, 30]; and, most remarkably, (5) unlike many otherorganisms, they can enter a dormant phase if environmental conditions are not adequate for life (namely food and humidity). Thisdormancy phase can last long periods of time (on the order of years)
and can be reversed if the environmental conditions become again
suited to life (i.e., in general, they resuscitate from dormancy with
the introduction of moisture and food in the surroundings) [37].
These latter two properties also influenced our choice of slime moldas a suitable candidate for exploring physical care interactions inside a functional interactive device. Their ability to enter a dormant
phase allows us to leverage some of the benefits of virtual care (i.e.,the virtual pet never really dies and can be suspended) while benefitting from the advantages of a living organism, i.e., it physicallyreacts to care/food, etc.—which we hope influences the relationshipbetween user and device by adding a sense of responsibility. And
last, due to their variable size, they can be incorporated into a small
wearable device or used in large displays [46, 61].
Importantly, we acknowledge that introducing a physical organism in the function of an interactive device is not without technical limitations. Organisms display a range of disadvantages compared even to a simple copper trace (e.g., requiring food, instability,
fragility, uncertainty of growth [3, 64]). However, our focus is on
the benefits of introducing a physical organism in the function of
an interactive device, in other words, in the added friction fromthe physarum (as any living organism) requiring an environment
conducive to life, which in our concept the user is responsible forproviding.
Finally, while there have been explorations into the potential ofphysarum as conductors or sensors in a circuit [3, 5, 71, 72] ours isthe first to explore utilizing this organism inside an actual everyday
interactive device, such as a smartwatch.

3

OUR CONCEPT: CARING FOR
INTERACTIVE DEVICES BY INTEGRATING
LIVING ORGANISMS

We present our concept of implementing physical care in interactive devices by integrating a living organism in the function of
the interactive device. Figure 1 depicts our concept through oursmartwatch prototype. In this prototype, the user delivers the physical care by giving the slime mold water and oats. If the organism
thrives, its growth becomes electrically conductive and acts as a
circuit wire enabling functionality in the device. In our concept,
much like friction-based UIs, the care is not relegated to the background but instead, becomes an immediate aspect of interactingwith the device. This reminds the user that this kind of interactive

Jasmine Lu and Pedro Lopes

Figure 3: A visual depiction the three principles key to ourconcept via the example of our slime mold smartwatch.

device is not made only from inert materials, but that there is aliving organism integrated with it. While caring for this device, users
experience real consequences, including that the organism might
go dormant or die if they do not create a favorable environment.
While our prototype takes the shape of a smartwatch, we recognize that many other forms/designs can realize our concept. As
such, in Figure 3 we depict the three key properties that are required
to instantiate our concept: (1) the interactive device must feature aliving organism, (2) users must be responsible for delivering care,(3) organisms must participate in the device’s functionality.
Principle 1: interactive device features a living organism.
Our concept relies on qualities evoked from interaction with a livingorganism, which might inspire a different quality than if the device
was purely inorganic. It’s difficult to feel kinship with materials
when they are not as responsive as organisms. Whether plants,
fungi, bacteria, animals, slime mold, or humans, all need the rightenvironmental conditions to thrive. Thus, living organisms offer
many material qualities that create high stakes (quite literally life
or death) if the environment they inhabit is not conducive to life.
Principle 2: user is responsible for care. While there aremany systems that can provide care automatically (automatic watering/feeders or humidity-controllers), our concept puts the users
in charge of the act of care. If an automated system would handle
the care for the user, it could quickly fall back into the sort of virtual
care relationships created where delivering care is a frictionlessexperience (i.e., a push of a button in a virtual environment). In
requiring the user to perform care, the user also becomes a partnerin this relationship between user, device, and living organism.
Principle 3: organism participates in the functionality. To
further encourage care, the state of the organism must correspond

Figure 4: An overview of the physarum enclosure showcasing
the layers and how it reconnected to the device via magnets.

Integrating Living Organisms in Devices to Implement Care-based Interactions

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

Figure 5: Stages of interaction embedded in our smartwatch device: (a) the wire is not grown; no heart rate is available. (b) theuser “cares for the device”, by caring for the slime mold (feeding it water and oats); (c) when the slime mold becomes healthy, it
conducts electricity and enables the heart rate sensor; (e) if the user neglects to care, the slime mold dies and disables the sensor.
to some aspect of the interactive device’s functionality. This could
take the form of conducting electricity inside the device’s circuit (asin our smartwatch), forming an essential structural component of
the device, or any other means to enable a functionality. Moreover,from the user’s standpoint the way that the organism contributes
to the functionality must be as explicit as possible. Thus, if the user
immediately recognizes the impact of the organisms’ health in thedevice’s functionality, they can understand the impact of the carethey deliver—offering more potential to deepen the user-device
relationship.
Now, we explain how we instantiated these three principles andcreated a new kind of device by engineering a smartwatch that
includes a living slime mold.

4

4.2

Dormancy and Resuscitation

Slime molds have a reproductive cycle like most living organisms
and reproduce via the formation of spores. However, one interesting aspect of the slime mold lifecycle is that they can (almost
immortally) oscillate between a living and a dormant version of
itself. Essentially, slime mold can be dried up and exist for years
in their dormant sclerotium state. When environmental conditions
become more favorable (with the introduction of food and water),they will be resuscitated and, therefore, reenter their “living” state.
This cycle between living and dormant is fundamental to our interaction design, and we focus on interacting with the physarum inbetween these two states as seen in Figure 6.

OUR INSTANTIATION: SLIME MOLDSMARTWATCH

We present an example implementation of our main concept, an interactive smartwatch that includes a slime mold as a living wire. As
depicted in Figure 5, the heart rate is only enabled if the user cares
for the slime mold so that it grows healthy and conducts electricity.
If neglected, the slime mold dries up and becomes non-conductive,
disabling the heart-rate sensor. To accelerate researchers interested
in reproducing our device, we made it open-source1 .

4.1

Designing a Physarum Enclosure

We created an enclosure for the organism enabling the user tocare for it (by delivering oats or water) as seen in Figure 4. This
enclosure is designed to direct the organism’s growth in a single
direction. The enclosure is primarily made of clear acrylic but ineach well, the bottom layer consists of a magnet. The physarum
grows on one side of the magnetic surface, and the other enables aquick connection to the device’s circuit. The circuit only becomesfully connected if physarum grows between both wells, throughthe bridge.

1 https://lab.plopes.org/#integrating-living-organisms

Figure 6: Photographs (7.5x magnification) of a slime moldoscillating between living and dormant stages.

4.2.1 Implementing a Care-based Interaction. One of our principles is making the care immediate and clear to users. Thus, ourenclosure’s lid is transparent so that users always see the slime
mold and, moreover, it allows for caring for the physarum by: (1)UIST ’22, October 29–November 02, 2022, Bend, OR, USA

Jasmine Lu and Pedro Lopes

Figure 8: Schematic of circuit implemented in our smartwatch.
Figure 7: An overview of the main electronic components
embedded in our slime mold integrated smartwatch.

removing the compartment, (2) feeding it or watering it by dropping oats or water into the wells under the lid; and (3) reattachingit.
In addition to enabling care, we further encouraged users to carefor the physarum by incorporating the state of the physarum’s
growth into the functionality of the smartwatch device. If thephysarum has favorable enough conditions to grow a wire, it canconduct electricity along that wire. If current can pass throughthe physarum wire, the heart rate sensor that is embedded in thesmartwatch receives power, enabling the user to see heart rate data
and the resistivity of the physarum wire. We opted to associate theheart rate sensor functionality to the physarum growth as a symbolof livelihood between both user and physarum.

4.3

Electronics Design

The device itself consists of a custom PCB, depicted in Figure 7,
which integrates: (1) our physarum sensing circuit (described below), (2) an SSD1306 OLED display, (3) an Seeeduino Xiao microcontroller, (4) a MAX3010 heart rate sensor, (5) a RV-3028 real-timeclock, (6) a linear-resonant actuator (LRA), and (7) a 3.7V 200mAH
Li-Po battery.
The microcontroller (SAMD21 Cortex M0) communicates withmost sub-components via I2C (display, real-time clock, and heartrate sensor), except with the LRA, limit switches and the physarum
wire. To allow users interact with the device, besides the display,
we also provide touch input, vibration output and detection of
the physarum enclosure removal. We realize the touch input using a capacitive sensing pad, embedded directly on the 3D printed
enclosure, which is sampled by the SAMD21’s internal QTouch
firmware. To deliver vibrations, we actuate the LRA using a MOSFET (SSM3K15ACTC). To detect if the user removed the physarum
enclosure (and to encourage them to put it back) we added two
surface-mounted limit switches (JJJHLGG200NOPMRTR) sensed
by the microcontroller via a pull-down circuit. Finally, so that thesmartwatch’s display can depict not only the physarum’s wire state(described below) but also the current time of day, we integrated
a custom-designed real-time clock using the RV-3028. Even if themain battery (3.7V 200mAH Li-Po battery) is drained, the real-timeclock dynamically switches to a backup small 3V coin cell battery(directly soldered onto the PCB) which keeps the time accurately
until the main battery (and thus the microcontroller) become operational again.
4.3.1 Physarum wire circuit design. We engineered a circuit sothat when the first physarum wire was formed across the twoelectrodes, it would enable power to the heart rate sensor. Thus,
the state of the physarum wire corresponded directly to whether
the heart rate sensor was powered. Additionally, we also sense
the resistance of the physarum to provide feedback to the user
about its state. To accomplish this, we designed the circuit shownin Figure Figure 8. This circuit implements two functionalities: (1)it provides a resistance sensing over a 2MOhm voltage divider,which are then fed into an opamp (MC33202) in a voltage follower
configuration, allowing the microcontroller to sample the current
value of the physarum wire; and (2) a subsequent opamp (MC33202)
in a non-inverting amplifier configuration, the output of this isdirectly fed to the heart rate sensor. The resulting effect is that if
the physarum wire is grown across and healthy (conductive andless than ∼3.5MOhm resistance) it will power the heart rate sensor
module. This was specifically designed to be not a software enable
but baked onto the hardware.

5

TECHNICAL EVALUATION OF OUR LIVING
WIRE

Choosing a substrate. As with any living organism, growing
healthily requires favorable conditions. At the same time, physarum
can withstand many conditions and can rapidly grow given foodand adequate humidity. We tested growing physarum on a variety
of substrates, including agar, metal, paper, cloth, and plastic (PLA,
acrylic). We found that they were able to grow across all thesesurfaces with minimal variation. As such, in our device, we choseto grow ours on plastic and metal (for the electrodes).
Choosing nutrition. In nature, physarum consume types ofyeast, bacteria, and fungi. Oats present a convenient substitute forthese foods. Via months of testing and growing dozens of physarum,
we found that providing oat flakes moistened by water and adding
an additional one water drop about two times a day was adequate
for encouraging physarum wire growth across our enclosure.
Wire formation speed. To observe the speed of the physarum’s
growth, we conducted a series of time lapses (taking a photo perIntegrating Living Organisms in Devices to Implement Care-based Interactions

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

Figure 9: Photo captures from a timelapse of one physarum wire growth over the course of 20 hours.
minute) of the physarum’s growth and drying out in our enclosure.
We found that across three trials, it took about 12.67 hours (SD=3.05)
to form a wire and 16 hours (SD=9.64) for the physarum to break
its wire without oats/water. After oats/water were reintroduced, it
took approximately 10.33 hours (SD=4.93) for the wire to regrow.
One of these timelapses is annotated in Figure 9.
Light influence. Physarum also prefer to grow in the dark andwhile we did not incorporate this into our design, we encouraged
users to allow them to grow in the dark when not wearing thedevice. To test the impact of light, two physarum petri dishes wereplaced directly under a light source; one covered. We saw negligible difference between the two in terms of growth and ability toresuscitate them.
Physarum’s resistance. While previous work characterized
the resistance across a single physarum wire strand [3] (i.e., an extremely thin physarum wire), we found that our enclosure resulted
in different resistances across the wire. This is likely due to two
factors: increased wire formations (especially in parallel) significantly change the resistance, or residual water during care modifies
the resistance. Thus, we characterized 12 physarum samples growninside our enclosure, and measured their resistance every 8h after
one single initial care routine; then, no more care was provided, andwe measured how the resistance changes once they dried up. Resistance was measured using a resistance-measuring circuit [65] and ahigh-precision ammeter (6.5 digit, 1nA accuracy). Figure 10 depicts
the results, which as expected, demonstrate how the physarum
wire resistance dips once a wire has formed and gradually increases
as it dries. These measurements were conducted in laboratory conditions: container was closed and non-moving, kept at a stabletemperature and only exposed to light during measurements.
Variability of living wire. As with all organisms, there is variability in growth that cannot be fully controlled. While we presented this technical evaluation to give readers an approximationof what they can expect when working with living wires, ultimately
their growth is not deterministic and can only be guided or nudged.
Variations in growth are typically caused by available space, light,
humidity, temperature, chemicals, etc. While all factors cannot be
controlled inside a smartwatch, our approach aimed at controlling
one factor specifically: available space for slime growth. We guided
growth using our tunnel-like structure. This ensured our device
could grow slime molds in a more repeatable and similarly timed
manner across different runs.

Figure 10: Resistance measurements (log scale) over 120
hours.

6

USER STUDY: PERCEPTIONS OF A LIVING
WEARABLE

To explore how users perceived a living wearable device that must
be cared for, we conducted a user study (in Figure 11), where wehanded over our smartwatch to five participants and asked themto wear it for 9-14 days (depending on interview scheduling andspeed of wire growth/drying).
We designed this study so that participants would experience two
distinct phases while wearing our smartwatch, which we depict inFigure 11 (1) caring phase (initial resuscitation of a dried physarum
until full growth of wire); and, (2) neglect phase (after interview 1,
participants were instructed to stop caring for the physarum until
dried and nonconductive)—this allowed us to collect feedback fromboth caring and non-caring stages. Through their daily entries andinterviews, we collected accounts of what feelings, perspectives,
and thoughts emerged from participants as they interacted with thisdevice. Our study was approved by our ethics committee (IRB200290).

6.1

Participants

We recruited five participants (average age: 30.4, SD=11.06; all participants identified as women) from our local institution. Participants were compensated with 100 USD.

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

Jasmine Lu and Pedro Lopesthem by asking general questions about their experience and follow
up questions from their diary entries. After this interview, we instruct them to not care for the physarum (no longer provide waterand oats) but to continue wearing the device and filling out daily
entries.
Interview 2: post-drying. Once the physarum was dried andno longer enabling the device’s heart rate sensor, we conducteda final interview and concluded the study. This final interview
had two halves: in the first half, we asked general questions about
their experience in the same format as the first interview; while, inthe second half the experimenter we asked more questions about
the type of care they performed and how it related to their otherexperiences with living organisms and devices. As part of thissecond half of the interview, we also asked participants to engage
in an exercise to imagine future physarum devices.
This study structure was designed in a way that allowed participants to freely provide feedback and minimize the chance ofexperimenters biasing participants with specific questions on specific topics, i.e., in all our daily feedback forms, first interview andthe first half of the final interview, there were no direct questions
on specific topics or mentions or specific topics made by the experimenters. Only in the second half of the final interview, theexperimenters explicitly asked more directed questions.
Figure 11: An overview of our study structure with a timelineof major events in the study: caring phase and neglecting
phase.

6.2

Apparatus and On-boarding Instructions

Apparatus. Participants were provided our slime mold integrated
smartwatch and materials for care (water dropper and oats). The
physarum wire enclosure was pre-loaded with dried physarum in
one well and oats in both wells.
Onboarding. Participants were instructed to wear the watch for
as much of the day as possible. We explained how to care for thephysarum and how to use the smartwatch. We instructed to carefor the slime mold by providing one water drop twice a day andoats every two days. Whenever not using the device, (e.g., during
sleep), we asked that they kept it in a darker environment. Our
device additionally provided reminders (via its display and throughvibration) to water the physarum every four hours (i.e., twice during
daytime, not at night) and to feed the physarum every two days.
Finally, we provided two recommendations in the event of more
extreme circumstances: (1) wearing the watch under a sleeve during
extremely cold weather; and (2) scooping out any contaminatedgrowth and provide more oat and water (only happened once during
our study).

6.3

Study Procedure

Daily feedback. Participants filled out daily update forms. The
update form asked for the physarum status, the type of care theygave to the physarum, a picture of the device, and notes on any
reflections or experiences they had on that day.
Interview 1: post-growth. Once participants grew a physarum
wire and had a heart rate enabled watch device, we interviewed

6.4

Results

Using participants diary entries and transcribed interviews, the firstauthor conducted an open coding of materials and themes wereconstructed and further revised by all authors. The goal was twofold: (1) cluster similar accounts, (2) identify in which stage of thestudy this account was elicited. We organize participants responses
into three sections: (1) caring phase – from initial receiving ofdevice, growth of wire, to first interview, (2) neglecting phase –after first interview, not caring for the physarum until it dried, andfirst part of last interview, (3) guided reflection– second part ofexit interview, which marked the only moment where researchers
asked direct questions about how this experience was different
from previous interactions with devices.
6.4.1 Observations from phase 1: Caring Phase. On average, participants took 4.4 days (SD=3.43) to grow a wire and participants engaged in caring for the physarum for an average of 7 days (SD=2.82)
before their first interview. During this interview, the experimenter
asked general questions about the experience of wearing the device(what difficulties they experienced, if their perception changed overtime, etc.) and asked participants to further expand on their submitted daily updates. These accounts of participants experiences
are clustered and summarized below.
Fascination with the organism. For all participants, this wastheir first experience interacting with a slime mold. The novelty
of wearing a device that housed a slime mold was expressed byall. P2 stated, “[at the start] I don’t even believe that they’re alive,
so when I give them water and oats (. . .) that is the most exciting
part, seeing that they actually ate the oats and keep growing mademe feel very, very excited.” Moreover, all participants reported thatthey “showed off” their device to friends and coworkers during thisphase. In recounting a family dinner where the device and study

Integrating Living Organisms in Devices to Implement Care-based Interactions

became a topic of conversation, P4 explained “I think it piques a
lot of people’s curiosity and imagination”.
Care strategies. While participants were provided the samecare instructions, they adopted various strategies. P1 initially wrote
down the care in her notes, but this gradually settled as a routine.
P2 and P5 used visual observation to decide when care had to beprovided. At one point without experimenter instruction, P2 added
more dried physarum (which was provided as a backup) into thewell to encourage growth, explaining that “they could support eachanother”. P3 relied on the care reminder alerts, noting that thesereminded her that “it had these needs and it felt more like a realthing even though it was just like an alarm clock going off (. . .)more real and alive”. P4 described her process of learning to carefor the physarum as a “lesson in responsibility”.
Friction while interacting with an organism. During thisphase, participants also experienced several moments of friction.
For some, this arose from a lack of control over the physarum. For
instance, P3 experienced moments of friction due to the aestheticsof the living organism stating, “I suppose it is a living thing so
I can’t expect it to be not as messy”. The responsibility for thephysarum required from participants also appeared as a source offriction. During the study, P5 had a fever yet still provided care forthe slime mold, explaining that she felt “worried about whether
their slime would be okay” even during her illness.
Developing a connection. All participants expressed various
feelings of connection with our device. P1, P2, P4, and P5 all described it as a little friend and/or pet. P2 expressed, “it’s always
good to be accompanied by some living creature, I really like different, animals or plants. (. . .) carrying this little friend also mademe feel happy and peaceful”. P4 noted that she would be remindedby the slime mold’s presence by its smell, even stating that it felt
endearing, “my cat’s kind of have a smell, dogs have a smell, thephysarum, I recognize the smell and it smells kind of, organic, it’skind of yeasty but not like decaying, it smells alive”. In recalling anexperience where she had to take a long drive, P4 explained, “oh, I
gotta bring my little pet mold friend, during the drive, I was also
thinking about how I used to be really into Tamagotchis (. . .) withthe physarum, (. . .) it has this smell to it which your Tamagotchis
don’t have, it has a sense of physicality, (. . .) they’re definitely different”. P1 stated that their personal care routine ended up linked
to the device’s care routine “I think every time I fed myself is when
I would remember to at least check it, I think that was actuallyquite linked”. While she was sick, P5’s partner helped take care ofher as well as helped to take care of her device. P5 recounts, “I was
taking care of the slime and feeding it oats and stuff, my partner
was also feeding me oatmeal because I was sick and so she was likeyou’re my little slime and I was like yeah, I am (. . .) then she started
calling me her slime because I mean me and the slime, like, we were
eating the same stuff, (. . .) we were both being fed and watered”. P2& P4 also stated that the visual appearance of their device affected
their mood. P2 explained that growth made them feel refreshed. P4
associated the bright yellow of the physarum with happy feelings,
noting this affective quality several times in her diary entries andin her interview.
6.4.2 Observations from phase 2: Neglecting phase. On average
participants took 1.8 days (SD=1.3) to dry their wire and they were

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

in this neglecting stage for an average of 5.2 days (SD=1.09) before
their closing interview. The experimenter asked general questions
about the device and asked to expand diary entries for this phase.
We also asked if participants could imagine themselves wearing adevice like this in their daily life.
Transition to neglect. After being instructed to neglect thephysarum, participants varied in how much they struggled to transition. All participants expressed that there was less work involved
with our device when neglecting vs. caring, citing that they did nothave to think about the device as much. P1 stated, “I felt kind ofrelieved that I didn’t have to take care of the watch anymore, but
at the same time I was super surprised at how quickly it stopped
sensing”. P4 described the transition as “kind of a mindset shift
like. . . now I just don’t need to take care (. . .) I think the on the
responsibility side, [I] kind of let loose and I detached a little bitfrom feeling really connected.” All participants also expressed feeling sadness or guilt in the process of neglecting the slime mold. As
a note, many participants referred to the dried slime mold insidetheir watch in this state as “dead”, despite technically being in “dormancy” as it can be resuscitated. In fact, the physarum inside theirsmartwatch at the start of the study had been in dormancy before
their initial care.
Change in interaction. All participants expressed that theirinteractions with the device changed during neglect. One of P1’s
diary entries indicated “[I] completely forgot to wear the watch
today (. . .) not having to take care of it (. . .) has made it harder tocheck up on it and wear (. . .) [it] is now definitely dead”. Additionally, she expressed, “I think it became more like a normal watch”.
On the other hand, P2 had a very different experience where she
decided to avoid looking at the dried slime mold, stating “[it] mademe a little bit sad”. Also, while she had excitedly introduced thewatch to others during the first stage, she didn’t show off the watch
in this stage and expressed anxiety over having to explain its driedstate to others. P4 noted that “[during the growing phase] I felt
motivated to keep it on and check up on it a lot, but not having todo that, I kind of treated the watch more like an object”. Similarly,
P5 explained “I didn’t feel like connected to it really, in a way I wasjust kind of like, yeah, there’s nothing special about it. Now, it’s
just like a watch, so you know, there’s no purpose of caring for it”.
Would you wear this device? When asked if they would wear
this type of device, participants had varied answers. P1 said she
was split as she enjoyed it more when at home taking care of it,
but outside she felt responsible for the physarum’s wellbeing in
the cold. Similarly, P2 expressed that she might want to wear thedevice for about a week, but “after that, I think it’s the same feelingwhen you have a pet, you like his company, but you don’t want totake the risk that he gets ill or dies”. P3 expressed that they would
be more interested if it featured another organism “like a plant”. P4
expressed that she would as she found learning how to care for theorganism fun. P5 explained, “I would be happy to wear it especially
if I was taking care of it, it can serve as a nice reminder for myself
to get a drink of water or something”.
6.4.3 Thematic Questions. In the final part of our exit interview, we
asked participants a series of questions to try to ascertain how theirexperiences with our watch different from the type of relationships
they had previously encountered with devices, virtual pets, etc.

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

Regular vs. physarum-integrated watch. Both P1 and P2 wear
smartwatches regularly during exercise. When asked to contrast
the experiences, P2 stated “the [regular] watch is only a tool (. . .)I don’t need to take care of it, it will not turn grey or need extra
care, so it’s totally different (. . .) right now, if you asked me todraw a picture of it [their own smartwatch], I can’t, but for this[physarum] watch, I can draw every detail”. P1 similarly described
smartwatches as tools when comparing experiences, explaining “[aregular smartwatch] is supposed to help me reach a goal, (. . .) but
the other [physarum] watch felt like this is some [thing] I had totake care of, so it was like it wasn’t a one-way relationship, I was
taking care of it, and it was like giving me the time or a heart rate
like as pay back, so it was like bi-directional”. P4 wore a watch inthe past for a short period of time and compared the two by stating“I think the normal watch was definitely easier to have mindlessly
on. With the living smartwatch, I was actively thinking about it,
and while I was taking care of it, was monitoring [it]”. P5 neverregularly wore a watch device before but contrasted her experience
with other devices by explaining, “other pieces of technology. I
would say I have an ambivalent relationship with them. I don’t carea ton about them. I don’t negatively or positively think about them,whereas I did think both positively and somewhat negatively about
the slime”.
Virtual pet vs. physarum-integrated watch. While we did
not screen for participants with prior experience with virtual pet
interfaces, P1, P2, P4, and P5 had previous experiences. P3 hadpreviously worked with kids and observed play with Tamagotchis.
When asked to contrast the experiences, all participants cited thephysical liveliness as the most significant difference but commented
on different qualities liveliness brought to their experience of care.
P1, who had interacted with Neopets (a website where users canown and care for virtual pets) explained how the physical presenceof the physarum on our device made her more conscious of the carethey needed compared to Neopets, which could be easily forgotten
for weeks. P2 contrasted caring for our device with her experiencetaking care of her Sims (a game where players care for virtualhumans). She stated that the experience “is quite different because
the physarum are not virtual, even though they’re attached with theelectric device, the watch, but [the physarum] itself is not virtual.
It’s real (. . .) in the [Sims] when your character die, you just create
a new one without any effort, you just click the button, and thena new character is born and then everything is as usual, but this[physarum], you need to take extra care.” Similarly, in recollecting
what she observed with Tamagotchis, P3 stated, “with something
like a Tamagotchi, it was programmed to work pretty logically (. . .)but with organisms there’s more uncertainty it may not live or
grow even if you did all the right things”. P4, who also had previous
experiences with Tamagotchis, various web-based pets, and a robot
dog toy, stated “I felt like I had to be a little more responsible withthe physarum, because with a virtual pet, you can just kind ofneglect it and then come back to it (. . .) having some experience
with real pets makes me more reluctant to neglect things, I felt
more responsibility for it because if I was that way with my catsthat would just that would not be okay”.
Care for other living things vs. physarum watch. All participants had previous experiences in caring for living organisms
whether plants or pets. P1 found the experience quite different toJasmine Lu and Pedro Lopes

taking care of her houseplants stating, “they’re stationary things
that you have a schedule [for] and you take care of them, and you
are only aware of them when you’re at home. I don’t ever think
about my plants when I’m not home. That’s not really a worry that
I have (. . .) I feel like it’s closer to having a dog than having a plant
because you gotta walk your dog (. . .) I think that level of concern
you feel about a dog interacting with the world is maybe, at somesmall level, like the concern that I had for the watch being exposedto the elements”. P3 felt the process of caring for both the physarum
and her garden plants was similar in the level of uncertainty it involved because she’s “not exactly sure how much to water them,
how much fertilizer to give (...), so it had a lot of similar uncertainty,
you don’t have total control over it”. P4 equated the processes oflearning to care for plants, her pets, and the physarum in a similarmanner.
Care for electronic devices vs. physarum watch. We asked
participants to contrast the care they gave to their electronic devices(repairs, maintenance, cleaning, etc.) to the care they provided totheir physarum-integrated watch. P1 explained that the care felt
different because of the similarities between physarum’s needs andher needs, “giving water and oats, which are also things we giveourselves, like I eat oatmeal, and I drink water, it feels more like ananimal or it is a living thing (. . .) the fact that I give it nutrients that
I also give myself that makes it even more like a living thing”. P2
also noted a difference, “this smartwatch, I feel I’m connected withit, because it has the living part and we can build the connection
very quickly, from the first day, I start to be connect[ed] with it,
but with my device, it might take years to build the relationship”.
P4 stated that there were different stakes at play, “I don’t think ofcharging my devices as like feeding them, whether they need it
to survive or thrive, it’s kind of the same no matter what (. . .) but
with the physarum, you can tell if it’s more or less happy (. . .) I
guess I was more concerned about the well-being of the physarum
than I would be for an electronic device”. P5 noted that “during the[caring phase] it definitely felt like more of that urgency (...) I’d say
I was more motivated to care for it on a daily basis than I would beother electronic advice devices.”
How would you dispose of the watch? P3 stated that theymight dispose of the watch itself but keep the physarum. P2 statedshe might “sell the watch so that it wouldn’t be left by itself andsomeone else could enjoy”. P4 stated that she would try to passon the device, “I think I would just try to show it to a friend andpass it on (. . .) if you really couldn’t take care of a pet anymore,
you would try to rehome it”. P5 felt unsure and even stated that
she had been wondering before being asked this question, stating,“I have no idea, because I always feel like I don’t know what to do
properly with technology anyway, like, how do you even get ridof technology? (. . .) I would probably feel really bad throwing theslime away, so I don’t know what I would do”.
Future version? When asked to imagine a next instantiation ofa physarum-integrated device, P1 envisioned a child’s night lightor a solar panel with a physarum; P2 envisioned a vase with aphysarum; P3 envisioned the physarum inside the circuit for an indoor fan, something she would “keep next to her window and plants
at home”; P4 provided two visions: one in which the physarum assists in an interactive device that communicates the needs a tree

Integrating Living Organisms in Devices to Implement Care-based Interactions

has (suggesting enlarging caring relationships to another organism), and the second in which a physarum grows and connects tomultiple points on a music synthesizer’s circuit board, enabling thecreation of sound; finally, P5 envisioned a device with “emotes forthe slime mold”, enabling it to express happy or sad states.
6.4.4 Summary of Findings. We discuss the specific topics we noted
in reviewing participant accounts of their experience.
Sense of responsibility. Over the course of the study, participants exhibited a sense of responsibility for the device. This wasmost pronounced during the caring stage. Additionally, participants
adopted various caring strategies that even included protecting thedevice from external factors they thought would damage it (e.g.,cold). This was also demonstrated by the struggle some participants
felt when we instructed them to neglect the physarum. Last, participants comments depict how the fact that the device was dependent
on the participant’s care and contained a physical living being gavethem a sense of responsibility that was distinct from virtual pets ortheir other devices.
Affinity to organism and reciprocal relationship. Almost
immediately, most participants started to refer to their physarum
as a little friend or pet and explained how they liked the companyof another living organism. Participants often described a feelingof relatedness in providing water and nutrients, which humans
themselves also required. An example of this is how, at times, participants connected their own self-care to the physarum care. Thisaffinity towards the living organism in the device was even more
pronounced when participants were asked to contrast their experiences with other nonliving devices. Participants described thelivingness as a quality that allowed for a faster connection whereas
connecting to their devices often took years. Additionally, participants described their relationships to their devices as one-way
or merely functional. On the other hand, with the physarum integrated watch, the relationship felt more “bi-directional”, as P1 put
it.
Affective responses to device’s state. Throughout the study,
participants described emotional reactions to the state of their device. Even qualities like the color of the physarum or the smell of
the physarum drew out emotional responses. Participants also expressed feeling attuned to the physarum and as if they experienced
empathy towards the physarum.
Study limitations. We also acknowledge that our study findings
come with their limitations. We focused on studying a specified
interaction cycle (dried/dormant with heart-sensor disabled, tohealthy with heart-sensor enabled, and back); to create this cycle
we requested that participants halted care for the device. However,
future studies might elicit different responses without a prescribed“neglect” phase. Also, as with most studies of this type, our findings might exhibit some degree of novelty effect as participants
have never experienced such a device. Furthermore, this limits how
much we can extrapolate about users’ physical caring experiences
vs. virtual care. A prolonged study might offer additional insights,
after the novelty wears off. Our prototype is also not as “polished”
as a commercial smartwatch, creating additional frictions duringuse. For ease of care, we designed the physarum enclosure as removable, but a different design where the physarum enclosure could
not be removed might also afford different responses. In the user

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

study, the slime mold was exposed to a number of unpredictable
external factors that could limit growth (light, cold/dry air, participants occasionally forgetting to water, etc.). Due to this, there was
likely some variability in growth that could not be controlled. The
cold climate the study was conducted in (February-March in the
Midwest United States) may have also affected slime mold conditions. Future studies will be needed to determine viability of wire
growth, particularly in extremely hot and dry climates. Last, as ouruser study consisted only of women, we note that our findings are
implicated by gender. Our participants often cited experience withtoys (often marketed towards young girls) as part of their interestin the study and care work itself is often gendered labor. While nota focus of our work, the role of gender in care relations for living
media interfaces should be explored in the future works.

7

DESIGN RECOMMENDATIONS

For others interested in expanding our work and instantiating their
new care-based interactive devices featuring organisms, we reflected on our experience to provide two sets of design recommendations: for slime-mold interactive devices and for future care-based
interactive devices using other organisms.

7.1

Collaborations with Slime Mold inInteractive Devices

During our process of working with slime mold, we were constantly
inspired by the organism and influenced by it.
Aesthetics. In our work, we displayed the slime mold in a clear
enclosure so that users would be able to see their physarum’s
growth as much as possible. Their enclosure also came with aremovable lid, allowing for easy access so that they could touchand smell the physarum too. In our study, participants all noted
these aesthetic qualities of their physarum during their experience,
often correlating it to their emotional response to the physarum or
as a reminder that the physarum is indeed, alive. As such we recommend designers make these aesthetic qualities of the physarum
accessible.
Responsiveness. Physarum have been shown to respond to awide variety of other stimuli too including light, heat, and chemicals.
Interactions could be designed to incorporate guiding growth byengineering attractants and repellants.
Lifecycle. The lack of immediacy and degree of uncertainty
involved in relying on physarum as a functional component of anelectronic device should be mindfully incorporated in the interaction design. Designers can even celebrate this aspect by emphasizing how functionality of a device only needs to be present for
certain periods of time and that sometimes access to the functionality ought to be limited (i.e., taking breaks from seeing your heartrate).
Sharing organisms. Physarum can easily be shared and regrown whether in their lively diploid state or dried sclerotium. As
such, interactions can be designed so that users can share healthy organisms, creating a communal experience with multiple physarum,
users, and devices.

UIST ’22, October 29–November 02, 2022, Bend, OR, USA

8

FUTURE CARE-BASED INTERACTIONS FOR
LIVING DEVICES

While we focused on one instantiation of our concept (the living
smartwatch), it can take many forms and generalize across different
devices. We provide recommendations for future care-based devices
featuring a living organism.
Mutual symbiosis. Fundamental to our concept is a care-based
relationship. We encourage designers to think beyond the humanin a “user” role (a one directional, extractive relationship), but asan agent that gives back as a caretaker. We also encourage designers include mutualistic symbiotic relationships as these promote abidirectional sense of relationship, rather than the traditional “userof this device”. Notably, our instantiation is not a truly mutually
symbiotic relation as we do take the slime mold out of their naturalenvironment for our purposes.
Uncertainty. Living organisms are not as determinate as the
traditional inert materials often used to make interactive devices.
This creates some difficulty in designing with them, but also enables more diverse, surprising states due to the uncertain way they
respond to external factors. This quality should be celebrated ininteractions with living devices to encourage new relationships
beyond expecting devices to be easy, fast, reliable, and purely at
our disposal.
Showcase the organism. In an interactive device that features
a living organism, the device’s form factor and interactions should
highlight the qualities of the organism. Rather than design devices
that “black box” their inner workings, the organism’s state andcontribution should be made immediate. Thus, the organism’s involvement is not overshadowed and feels more like a partnership.
Sustainability. Designers creating care-based devices with living organisms should always engage sustainably whenever possible.
This includes using ecological friendly or compostable materials,
disposing materials properly, considering ecological impact, etc.
While this work focuses on care for a living organism and device,caring interactions should and can expand to the larger environments and ecologies we are a part of.

9

CONCLUSIONS & FUTURE WORK

We explored care-based interactions by integrating living organisms in interactive devices. We instantiated this by engineeringa smartwatch where a user must care for a slime mold so thatit grows a wire that enables a heart rate sensor. We evaluated it
through technical evaluations and a study where participants took
the device home. Findings illustrated that the living nature of ourdevice created friction but also allowed for a sense of responsibility,
development of a reciprocal relationship, and a variety of affective responses. Our work highlights how designs around care canchange the relationship between users and their interactive devices.
Future work & integrating other approaches. Designing forexperiences that foster more reflective relations between humanuser, devices, and other organisms has gained interest in HCI [47,51, 57]. As the number of consumer devices exponentially increases,
the toll on our environment becomes more pronounced. We see ourapproach as one way to encourage users to reckon with this aspectof their device use. Rather than a user-device relationship built on
extractive use, we encourage devices where the user takes on a

Jasmine Lu and Pedro Lopes

caretaking role. This goal aligns with various other approaches by
the HCI community to create artifacts to question our relationships
with technology, and we hope that ours can fosters debate andinspires novel perspectives on this.

ACKNOWLEDGMENTS
This work was supported by NSF grants 2047189 and 1746045. Any
opinions, findings, and conclusions or recommendations expressedin this material are those of the authors and do not necessarilyreflect the views of any funding agencies.
We are grateful for the feedback from our reviewers, engagement from our participants, and support from our colleagues at the
Human Computer Integration Lab.
Finally, we would like to give a special thanks to Ian HandsPortman for our initial slime mold samples and to the entire slime
mold collective [66] for their knowledge and support.

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