Shaping Egocentric Experienceswith Wearable Cybernic Interfaces
Jun Nishida
University of Tsukuba, Japan / JSPS (-2019.03), University of Chicago, USA / JSPS (2019.04-)
jun.nishida@acm.org
ABSTRACT
Embodied experiences, such as muscle activity that should
be shared between patients and therapists, or a lower perspective of a child that should be shared with designers arebroadly categorized as embodied knowledge that cannot be
acquired by conversations or visual media, but only throughactive physical experiences.
I hypothesize that changing a person’s body, including
one’s perceptions, actions, and interactions, to that of anotherperson such as a child or a patient, while allowing active
interaction with the surrounding objects and people in a realworld environment, would provide more valuable as well as
empathic knowledge to school teachers, product designers,
and medical sta� when designing living environments orcommunicating with others. To achieve these new paradigms
to acquire embodied knowledge of personal experiences, I
designed the following two types of corporeal changes: 1)changing the visual and haptic perspectives into those of achild, and 2) changing the kinesthetic perspective to that ofa patient.
To achieve this, I developed wearable devices that cansense and intervene in human body functions directly forchanging one’s bodily sensation or perspective. This allows
the wearer to experience changes in perception, action, andinteraction while preserving the active, embodied, and social
experiences within a real environment; this is a bene�cialmethod for supporting the acquisition of embodied knowledge for the scenarios that are experienced.
I investigated the wearer’s perceptions, actions, and interactions throughout lab and �eld studies, and discuss how the
wearable systems contribute to the change of bodily sensation. These studies veri�ed that the devices have changed thewearer’s embodied and social experiences, and also gained
embodied knowledge and empathy toward di�erent people through the wearer’s active engagement with existing
environments. Interestingly, not only the wearer but also
the surrounding people changed their interaction toward
the wearer. It is assumed that the change in the wearer’s
body created new social context with surrounding people,
enhancing the shaping of bodily sensation.

Existing Environment!

!

Embodied Knowledge
DeviceIntervention

Active Interactions
Social & PhysicalFigure 1: Acquiring Embodied Knowledge of One’s Experience through Shaping Bodily Sensation

1 INTRODUCTION
Understanding the embodied and social experiences of aperson can play an important role in gaining knowledge or
empathy toward an individual or enhancing one’s experiencein the �elds of rehabilitation, design, and education. Theseembodied experiences, such as muscle activity that should
be shared between patients and therapists, or a lower perspective of a child that should be shared with designers arebroadly categorized as embodied knowledge that cannot be
acquired by conversations or visual media, but only throughactive physical experiences.
With the recent advancements in wearable technologies
and virtual reality techniques, human’s embodied experiences are being augmented beyond the limitations of space
and time. Wearable devices have already achieved an extension of the user’s presence in a remote place by sharing their�rst-person perspective [13] or by surrogating one’s body
into a robot [32] or other person as an actuator [19, 30]. Recent studies have also allowed users to not only extend theirpresence but also extend their sense of ownership into an another person’s body [27] or another life form [15], to gaining
knowledge by sharing multiple visual perspectives amongpeople [11], or to provide a third eye on their back to see behind them [6]. Interestingly, it was mentioned that changing
bodily sensations through such technologies also changes
one’s perceptions and actions [16]. Several design tools thatassists in conveying or reproducing one’s experience havebeen proposed based on changing bodily sensations.

Teachers | Designers | Therapists

2ChildrenPatients

SHAPING EGOCENTRIC EXPERIENCES

In this research, a new paradigm is proposed in order tochange one’s experience consists of perceptions, actions, andinteractions by changing one’s body into that of another person, while allowing active interactions with the surrounding
objects and people in a real-world environment, as shownin Fig. 1. This would provide embodied and empathic knowledge of one’s experience rather than describing or simply
presenting it in a symbolical or visual manner. The threehuman factors; one’s perceptions, actions, and interactions
would play important roles in de�ning physical and social
experiences and contexts with objects and people, thus constituting the sum of one’s embodied and social experiences.
Because all actions and interactions in the proposed experience style should be performed in a same interaction
manner with that in an existing daily life, the user’s conscious act which consists of voluntarily initiating actions,de�ned as subjective agency [9], should be preserved.
I call this experience that particularly includes both subjective agency to initiate actions and active interactions with auser’s intention, as egocentric experience in that a user isable to have an intention to initiate, then initiate, and freely
perform actions and interactions with his/her own intention
and timing.
Neuroscience studies have revealed that active interactions foster the change in bodily sensation, particularly body
representation [17, 18, 26]; therefore I fully exploit a user’s
egocentric actions and interactions for changing the bodily
sensation to change the user’s bodily sensation.
It is assumed that a user’s egocentric experience and bodily
sensation would continue to be changed with the active
interactions, thus I call this modi�cation of the experienceas shaping, as related studies in neuroscience also use thesame term [7, 8].
Interfaces which satisfy design goals including wearable
form factor, interactivity, and I/O correspondence, as a wearable cybernic interface.

Visual Persepctive
into a Smaller-person

Haptic Persepctive
into a Smaller-person

Kinesthetic Persepctive
into a Patient

Figure 2: Shaping Visual, Haptic, and Kinesthetic Perspectives into that of a Smaller Person and a Patient

Reproducing One’s Experience for Learning
Video materials [31], an illusion technique used for extending
the sense of ownership to a small doll [33], or an immersive
virtual reality technique for converting the user’s body intoa smaller avatar [1] have been used to create the sense ofbeing a smaller person, through which the user’s experience
may feel passive. Several studies have achieved to change
one’s bodily sensation into that of elderly [5] and impaired
individuals [28] by wearable visual, haptic, or kinesthetic
systems while preserving the wearer’s active interactions.
Active, Embodied, and Social Experiences should be
Provided for Therapists, Designers, and Teachers
These conventional tools are able to partially transmit thecharacteristics or experiences of a person’s embodiment andtheir special needs to other people symbolically and visually;
however, the following drawbacks still remain:(1) Users receive the bodily information in a passive manner from these media, while embodied knowledge canbe acquired actively with physical actions.
(2) It is di�cult to provide embodied interactions, which
involve proprioceptive feedback that play importantroles in learning or even altering bodily sensation.
(3) It is hard to generate social interactions with people
through these tools, which is also an important formof feedback for the user’s physical actions because theuser is in a virtual space; this may result in isolationfrom the social and physical contexts.

Smaller-person Experience (Fig. 3)
Overview. In this research, I attempts to change the wearer’s
body representation to have a small-person’s perspective ina real environment, with a capability of full body interaction by using wearable devices (Fig. 2). The feasibility andproperties of active smaller-person experience in a RE were
investigated through both �eld and lab studies to discuss its
challenges and opportunities. To allow this, the concept ofa body representation transformation into a smaller personusing a wearable VR device has been proposed [21, 24, 25].
Visual stimuli plays an important role in recognizing the relationship between a user’s own body representation. Changing the height of the eye level to a lower position while

If it becomes possible to understand one’s experiences
in a real-world environment in an active, embodied, andsocial manner, a more empathic experience will be provided
for product designers and educational sta� when trying todesign living environments or communicating with otherpeople.
2

!

!
bioSync

Kinesthe t i c

D evice

Feed bac k

MuscleMuscleActivity

Actuation
Bios ignal

Figure 4: Representative Image of Blending Kinesthetic Experience

Figure 3: A wearable visual device that allows a user tochange their body representation, in realtime, to that of asmall-person

stimulation (EMS), as muscle contractions of the other user,
and vice versa.

allowing for FOV control will allow an egocentric visualperspective of a smaller person to be achieved. Tiny hands
and a shorter length of the upper limbs are other importantfactors enhancing the sense of being smaller [4, 14].

Contributions.
(1) Modeling of the blending kinesthetic experience basedon EMG measurement and EMS(2) Proposed a method for muscular stimulation with dynamic adjustment over a wide frequency range while
preserving EMG measurement capability(3) Implementation of bioSync devices with the same
electrodes used for EMG measurement and EMS toachieve kinesthetic I/O at 100 Hz via wireless communication(4) User studies of the interaction and the system inwhich kinesthetic I/O with low communication latency(approx. 20 ms) allowed synchronization of rhythmic
muscle contraction without visual and auditory feedback, and allowed perception of presented EMS contractions while users were contracting their own muscles

Contributions.
(1) Conceptual representation of shaping visual andhaptic perspective into that of a smaller-person(2) Development of two wearable devices: 1) a visualtranslator for mapping the wearer’s eyesight level onto
his/her waist position by using a head-mounted display(HMD) and a wearable camera module, and 2) a pairof passive hand exoskeletons for miniaturizing hand
gestures by using motion conversion mechanisms(3) Conducted user studies at a nursing school, a museum and a lab to explore how a wearer’s experience
regarding perceptions of interpersonal distance (study1), actions during handshaking and a peg manipulation(study 2), and interactions (study 3) can be changed

3 DEVICE IMPLEMENTATION
Smaller-person Experience

Blending Kinesthetic Experience (Fig. 4)
Overview. In this research, I aim to assist mutual understanding of one’s bodily activity during rehabilitations or sports
training by sharing kinesthetic experiences with multiple
persons, such as muscle contraction and joint rigidity, which
are di�cult to observe visually (Fig. 2). To achieve this, I
propose a blended kinesthetic interaction that allows synchronizing, adding or subtracting muscle activities between
two persons.
A novel style of interpersonal kinesthetic communication between two persons using wearable kinesthetic inputoutput (I/O) devices was proposed [22]. The system, called
bioSync, is illustrated in Fig. 4. Using this system, which consists primarily of a pair of devices, muscle contractions of one
user are detected by means of electromyogram (EMG) measurement and are reproduced, by means of electrical muscle

To realize the concept of changing a body representation
into that of a smaller person, I have been developing a wearable device to change the visual perspective, as shown in
Fig. 5. The visual translator comprises an HMD, a stereo
camera module, a sensor belt, a single-board computer withprocessing software, and a mobile battery. The developed
stereo camera module which is equipped with two �sh-eye
cameras (ELP-USBFHD01M-L180, Ailipu Technology Co.,
Ltd, HD@60fps) was developed. Each camera module has a
180 �sh-eye lens.The wearer attaches the sensor belt at theirwaist position. It has a nine-axis motion sensor (MPU-9250,
Invensense, Inc.) and a microcontroller (Atmel SAMD21, Atmel) for measuring the wearer’s waist orientation in the
yaw-pitch-roll format.
3

Single-board Computer(Openframeworks)& Stereo Audio

HDMI

Waist

Head Orientation

Orientation

USB2.0USB2.0Fish-eye Images

StereoImages & Audio

HMD

Participant

Hand Exoskeleton

Experimenter

Microcontroller(Ateml SAMD21)

USB2.09-Axis Motion
SPI

Fish-eye Cameras

Gyroscope

HMD

CameraAccelerometer
Microphones

Magnetmeter

Wire to contrain
range of motion

EY̲STA

Figure 5: System Architecture

EY̲SITHC̲STAHC̲SITWC̲STA

Figure 7: Wearer’s Perception: (a) Experiment overview (b)When the participant calls “stop" (c) Experiment conditions

ParticipantExperimenter

Recorded Video(POV from waist)

Figure 6: (a) System Architecture (b) Process Diagram

The exoskeleton transforms the scale of the wearer’s hand
gestures into the smaller hand size by using a custom linkmechanism, called a multiple quadric crank mechanism. The
exoskeleton has small urethane �nger skins connected to thewearer’s hand by link mechanisms so that the wearer’s �nger
movement can be transmitted to the �nger part directly.
Because the urethane-made child hand is actuated by themechanical link system, the wearer is able to receive realtime haptic feedback from objects while interacting.

Figure 8: Wearer’s Action: Experiment Setup and Conditions: (a) Watching a Video (b) Small-person Experience

experience of a smaller person, the following three factors,
which are essential for the understanding of the users, were
investigated.
1) Wearer’s perception: In this study, which was a personal space evaluation, when the participant felt smallerusing the developed device (WC_STA condition), the largest
personal distance was observed (Fig. 7). This could have beencaused by an oppressive feeling toward the approaching experimenter induced by the feeling of being small.
2) Wearer’s action: It was observed that the participants
raised their hands higher than usual when trying to shakehands with the experimenter because they perceived theirown body representation as being smaller (Fig. 8). It wascon�rmed that the experience of being a smaller personchanged the physical relationship of the wearer and thesurroundings.
3) Wearer’s interaction: The wearer’s interactions withthe developed device during demonstrations at conferencesand exhibitions were observed (Fig. 9). It was often observedthat the visitors behaved like a child, such as performinga protective pose when surrounded by adults, or talking
like a child. Interestingly, surrounding people such as young
students also treated the wearers like a child, and behaved
as teachers or parents by acting in an overbearing manner.

Blending Kinesthetic Experience
To achieve the proposed interaction in an actual environment, I developed a paired wearable kinesthetic I/O devices,
called bioSync (Fig. 6 (a)). Each bioSync device is equippedwith a custom designed electrode system that performs EMG
measurement and EMS simultaneously (Fig. 6 (b)). In orderto achieve fast and simultaneous measurement and stimulation operations using common electrodes, a gate switchingmechanism and a mechanism for discharging residual potential (the body retains a net charge following the stimulus)
were implemented. Each bioSync is also equipped with awireless communication module and a radio-frequency identi�cation (RFID) tag which is used to detect and pair withother bioSync devices by touching the wearer’s wrist to thepartner’s bioSync device.
4

USER STUDIES

Smaller-person Experience
To investigate how the wearer’s perceptions, actions, and interactions can be modi�ed through the proposed egocentric4Figure 9: Wearer’s Interaction: Interaction Observation

Figure 11: Rhythmic Activity Synchronization!
Partition

Hand Dynamometer

I/O Electrodes

Vibration Motors
Joint
Compliance

Figure 10: Transferring the wrist compliance by sharing antagonist muscle activity

Blending Kinesthetic Experience
To investigate how the wearer’s perceptions, actions, and interactions can be modi�ed through the proposed egocentric
experience of a patient, I investigated the following threefactors.
1) Wearer’s perception: Through the perceptual experiment, it was veri�ed that the bioSync users were able torecognize reproduced muscle contractions and rate themon a �ve-point scale while they were contracting their own
muscles at 50%, 25%, 0% maximum voluntary contraction.
Another perceptual study of sharing the level of wrist compliance between two persons was also performed (Fig. 10),which demonstrated that the participants recognized thelevel of the confederate’s wrist compliance at four levels[23].
2) Wearer’s action: I conducted a series of tests to verify
that the interpersonal communication via the kinesthetic
channel could support the synchronization of two persons’rhythmic muscle contraction timing (Fig. 11). The results
were used to assess whether the bioSync device could be
employed in practical scenarios, such as clinical gait rehabilitation and sports training, in which the synchronization oftiming plays an important role. The average measured sync

Figure 12: Demonstration: Impairment Experience

time was 8.1s (SD=3.91s), and the average reported sync timewas 13.8s (SD=3.94s).
3) Wearer’s interaction: I also conducted a pilot study on
providing a simulated embodied impairment experience at
exhibitions and conferences (Fig. 12). The participants tried
to grab a spoon, and to scoop up gummy candies with thereproduced tremor. The results suggested that reproducing
the neurological action of Parkinson’s tremors could enhance
the understanding of the disease.
5 DISCUSSIONS
Smaller-person Experience
Eye level a�ected the personal space
From the result, the eye level of the participant a�ected theperception of interpersonal distance because there is a significant di�erence between (3)HC_STA and (5)WC_STA conditions. The di�erence in eye level would create an oppressive
feeling toward the approaching experimenter. In addition,
the large neck angle in pitch axis also a�ected the perception5

of social relationship with the experimenter, because thenursing teachers usually interact with 5-years-old children.
One participant reported that he/she has a frustrating feeling rather than an oppressive or scary feeling, because theparticipant could not move the perspective higher although
their legs were fully extended. It is also presumed that theirinternal body representation also contributed to the changeof personal space.

Rhythmic Activity Synchronization
In the user study of the synchronization of rhythmic action,subject 1 reported that excessive involuntary contractionsa�ected the performance of the synchronization. This could
have been caused by the electrode positioning and personalmuscular characteristics. This indicates that a prior adjustment is required for each subject to normalize the perceptualand kinesthetic experience among users. Another aspect I
would like to address is the learning e�ect, which I could notverify in the current experiment since the number of trials
for each participant was small. However, I found that synchronization time is always shorter when the experimenter
who had longer prior training and participated in the entire experiment, follows the participant’s rhythmic action.
Another preliminary experiment showed that the rhythmic
actions of two persons could be synchronized even if they
are not assigned as an experimenter or a follower, and aretreated equally [29].

Perceived arm length and distance
The participants could think their arm length had become
shorter, as had their height, resulting in an increase in theperceived distance between hands. A similar phenomenon
was also reported in which the arm length changed the perceived distance in a virtual environment [14].
Familiar objects as a reference
Several participants stated that they realized the change ineye level only after they saw the experimenter facing them,although they had visited the experiment room several times
before and saw the desks positioned 2 m away from thestanding location during the experiment. From such comments, it is assumed that the participants used more familiar
objects as a reference to recognize the physical relationship between their body and space. It should be noted thatthe participants knew the height of the experimenter andhad su�cient experience with each other through conversations because they are from the same local organization. The
recorded head orientations also showed that the participants
looked up higher under (2) smaller person condition thanunder (1) video condition. From the result and observations,many participants looked at the experimenter’s face before
the handshake, suggesting that the level of face could be
used as a reference. Such existing knowledge based on motorand social experience could help the wearers recognize theirspace and physical relationship.

Embodied Impairment Experience
In the pilot study on the simulated embodied Parkinson’s
experience, I received considerable feedback comments thatindicated the existence of kinesthetic memory after the experiment. This suggests that reproduced kinesthetic impairment
experience may be more e�ective in learning the neurological characteristics of the impairment than learning throughsome other modality. Some visitors also reported experiencing the existence of a remote user’s presence throughthe kinesthetic channel, while synchronizing muscle activity between two persons. Thus, interpersonal kinesthetic
communication is capable of enhancing the feeling of togetherness and reality of existence, in a manner similar to thatof interpersonal haptic communication [2, 3, 20].
6

CONCLUSION

Smaller-person Experience
In this research, I explored how human perceptions, actions,and interactions can be changed through the egocentric experience of a smaller person in a real world environment.
From study 1, which was a personal space evaluation,
when the participant felt smaller using the developed device,
the largest personal distance was observed. This could havebeen caused by an oppressive feeling toward the approachingexperimenter induced by the feeling of being small.
In study 2, it was observed that the participants raised theirhands higher than usual when trying to shake hands withthe experimenter because they perceived their own body
representation as being smaller. It was con�rmed that theexperience of being a smaller person changed the physicalrelationship of the wearer and the surroundings. In addition
to this, using a rehabilitation peg board, it was observed that

Blending Kinesthetic Experience
Subjective Perceptual Experiment
In the perceptual experiment, the participants could recognize reproduced muscle contractions and rate them on a�ve-point scale accurately, while they were contracting theirown muscles. It was observed that the standard deviation
increased when the pulse width increased. This might be
the e�ect of the wearer’s voluntary contractions on the perception of the reproduced contractions. Another perceptual
experiment would be required to study this phenomenon indetail and to assess the relevance of the signal-dependency
noise theory [10], which indicates that neural control signals
are corrupted by noise that increases in variance as with thesize of the motor control signal increases.
6the developed exoskeleton decreased the user’s chronological hand function which would reproduce a smaller-person’s
physical capability, while preserving the wearer’s developmental hand function.
In study 3, I observed the wearer’s interactions during
demonstrations at conferences and exhibitions. It was often
observed that the visitors behaved like a child, such as performing a protective pose when surrounded by adults, or
talking like a baby. Interestingly, surrounding people suchas young students also treated the wearers like a child, andbehaved as teachers or parents by acting in an overbearing
manner.
These �ndings, challenges, and design considerations willbene�t further studies on the design of user experiences
based on changes in body representation while preserving
active and embodied interactions in a real-world environment.

Shaping Egocentric Experience
The general conclusion regarding shaping egocentric experiences with wearable cybernic interfaces derived from design,development, and evaluation were described. In contrast to
the related works that attempted to append or extend physical body functions, the proposed experience have successfully ampli�ed the participants’ knowledge, and particularly
embodied the knowledge of one’s embodied and social experiences. Hence, I proposed the conceptual representation ofshaping a body representation in a real-world environment
based on active interactions to reproduce one’s embodied
and social experiences.
A major attribute of the proposed experiences was thatthe interaction could be initiated by the participant’s voluntary action. The participant must create, interpret, andreview narratives of the experience by themselves throughreaching, seeing, touching, and speaking, thus increasing
their participation level toward the experience.
As another attribute, the interaction styles involved thesurrounding people, thereby allowing the participants to increase their awareness of other people. This situation allowed
for the surrounding people, apart from the wearer, to perceive as the wearer became a smaller person or a Parkinson’s
patient. These new social and physical contexts including an
oppressive conversation, protective posture, conceited look,longer interpersonal distance, and more supportive behavior
contributed to shaping the body representation repeatedly.

Blending Kinesthetic Experience
In this research, I proposed and modeled a novel style ofinterpersonal kinesthetic communication, called the blended
kinesthetic interaction that allows people to mutually perceive and interrupt each other’s muscle activity.
Through the perceptual experiment, it was veri�ed thatthe bioSync users were able to recognize reproduced muscle contractions and rate them on a �ve-point scale while
they were contracting their own muscles. It was also veri�ed that the kinesthetic interpersonal communication allows
people to synchronize the rhythmic action without visualand audio feedback. I also conducted a pilot study on providing a simulated embodied impairment experience. The
results suggested that reproducing the neurological actionof Parkinson’s tremors could enhance the understanding of
the impairment.
The pilot study regarding faster kinesthetic reaction andthe sense of agency not only demonstrated that the human’s
responsive action can be accelerated by wiring the two persons but also suggested that their sti� voluntary to perform
actions with reward at the right timing allows their senseof egocentricity, the subjective feeling of producing a desired consequence or performance initiated by their own
voluntary, to be generated. Further investigation regarding
the intervention timing and the sense of agency have been
investigated [12].
These �ndings would provide design ideas for the kinesthetic interaction, and contribute to potential applications
such as education, design, and medical activities, that reveals
new aspects of human behaviors for embodied and social
experiences.

7 ACKNOWLEDGMENTS
This work was supported by Grant-in-Aid for JSPS Research
Fellow (JP16J03777) and Scienti�c Research on Innovative
Areas (JP18H04182).
BIOGRAPHY
Jun Nishida is a PhD candidate in Human Informatics at
University of Tsukuba, Japan. His research interests include
designing experiences in which all people can maximize andshare their physical and cognitive capabilities to support
each other in the �elds of rehabilitation, education, and design. The latest version of this manuscript is available on myportfolio site (http://junnishida.net).
REFERENCES[1] Domna Banakou, Raphaela Groten, and Mel Slater. 2013. Illusory
ownership of a virtual child body causes overestimation of object sizes
and implicit attitude changes. Proceedings of the National Academy of
Sciences of the United States of America 110, 31 (July 2013), 12846–12851.
https://doi.org/10.1073/pnas.1306779110[2] Scott Brave and Andrew Dahley. 1997. inTouch. In CHI ’97 extended
abstracts. ACM Press, New York, New York, USA, 363. https://doi.org/
10.1145/1120212.1120435[3] Scott Brave, Cli�ord Nass, and Erenee Sirinian. 2001. Force-Feedback
in computer-mediated communication. HCI (2001). https://dblp.org/
7

rec/conf/hci/BraveNS01[4] Nicola Bruno and Marco Bertamini. 2010. Haptic perception after achange in hand size. Neuropsychologia 48, 6 (May 2010), 1853–1856.
https://doi.org/10.1016/j.neuropsychologia.2010.01.006[5] Carlos Cardoso and P John Clarkson. 2010. Simulation in user-centred
design: helping designers to empathise with atypical users. Journalof Engineering Design 23, 1 (April 2010), 1–4. https://doi.org/10.1080/
09544821003742650[6] Kevin Fan, Jochen Huber, Suranga Nanayakkara, and Masahiko Inami. 2014. SpiderVision. In the 5th Augmented Human International
Conference. ACM Press, New York, New York, USA, 1–8. https://doi.org/10.1145/2582051.2582100[7] Alessandro Farnè, Atsushi Iriki, and Elisabetta Làdavas. 2005. Shaping
multisensory action–space with tools: evidence from patients withcross-modal extinction. Neuropsychologia 43, 2 (Jan. 2005), 238–248.
https://doi.org/10.1016/j.neuropsychologia.2004.11.010[8] Patrick Grüneberg, Hideki Kadone, Naomi Kuramoto, Tomoyuki Ueno,
Yasushi Hada, Masashi Yamazaki, Yoshiyuki Sankai, and Kenji Suzuki.
2018. Robot-assisted voluntary initiation reduces control-related dif�culties of initiating joint movement: A phenomenal questionnaire
study on shaping and compensation of forward gait. PLoS ONE 13,
3 (March 2018), e0194214–15. https://doi.org/10.1371/journal.pone.
0194214[9] Patrick Gruneberg, Hideki Kadone, and Kenji Suzuki. 2015. Voluntary initiation of movement: multifunctional integration of subjective agency. Frontiers in Psychology 6, 320 (May 2015), 3–14.
https://doi.org/10.3389/fpsyg.2015.00688[10] C M Harris and D M Wolpert. 1998. Signal-dependent noise determines
motor planning. Nature 394, 6695 (Aug. 1998), 780–784. https://doi.
org/10.1038/29528[11] Shunichi Kasahara, Mitsuhito Ando, Kiyoshi Suganuma, and Jun
Rekimoto. 2016. Parallel Eyes. In Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems - CHI ’16. https://doi.org/10.1145/2858036.2858495[12] Shunichi Kasahara, Jun Nishida, and Pedro Lopes. 2019. Preemptive
Action- Accelerating Human Reaction using Electrical Muscle Stimulation Without Compromising Agency. In In Proceedings of the CHI
Conference on Human Factors in Computing Systems CHI . ACM, New
York, NY, USA.
[13] Shunichi Kasahara and Jun Rekimoto. 2014. JackIn - integrating �rstperson view with out-of-body vision generation for human-humanaugmentation. AH (2014), 1–8. https://doi.org/10.1145/2582051.
2582097[14] Sally A Linkenauger, Heinrich H Bültho�, and Betty J Mohler. 2015.
Virtual armŒşs reach in�uences perceived distances but only after
experience reaching. Neuropsychologia 70, C (April 2015), 393–401.
https://doi.org/10.1016/j.neuropsychologia.2014.10.034[15] Xin Liu, Yedan Qian, and Pattie Maes. 2017. Tree. https://www.media.
mit.edu/projects/tree/overview/[16] Lara Maister, Mel Slater, Maria V Sanchez-Vives, and Manos Tsakiris.
2015. Changing bodies changes minds: owning another body a�ects
social cognition. Trends in Cognitive Sciences 19, 1 (Jan. 2015), 6–12.
https://doi.org/10.1016/j.tics.2014.11.001[17] Angelo Maravita and Atsushi Iriki. 2004. Tools for the body (schema).
Trends in Cognitive Sciences 8, 2 (Feb. 2004), 79–86. https://doi.org/10.
1016/j.tics.2003.12.008[18] Marie Martel, Lucilla Cardinali, Alice C Roy, and Alessandro Farnè.
2016. Tool-use: An open window into body representation and its
plasticity. Cognitive neuropsychology 33, 1-2 (June 2016), 82–101. https://doi.org/10.1080/02643294.2016.1167678[19] Kana Misawa and Jun Rekimoto. 2015. Wearing another’s personality.
In the 2015 ACM International Symposium. ACM Press, New York, New
York, USA, 125–132. https://doi.org/10.1145/2802083.2808392[20] Hideyuki Nakanishi, Kazuaki Tanaka, and Yuya Wada. 2014. Remotehandshaking. In the 32nd annual ACM conference. ACM Press, New
York, New York, USA, 2143–2152. https://doi.org/10.1145/2556288.
2557169[21] Jun Nishida, Soichiro Matsuda, Mika Oki, Hikaru Takatori, Kosuke
Sato, and Kenji Suzuki. 2019. Egocentric Small-person Experience by
Changing a Visual Perspective. In In Proceedings of the CHI Conferenceon Human Factors in Computing Systems CHI . ACM, New York, NY,
USA. https://doi.org/10.1145/3290605.3300926[22] Jun Nishida and Kenji Suzuki. 2017. bioSync. In the 2017 CHI Conference.
ACM Press, New York, New York, USA, 3316–3327. https://doi.org/10.
1145/3025453.3025829[23] Jun Nishida and Kenji Suzuki. 2018. Wearable Kinesthetic I/O Device
for Sharing Muscle Compliance. In The 31st Annual ACM Symposium.
ACM Press, New York, New York, USA, 57–59. https://doi.org/10.
1145/3266037.3266100[24] Jun Nishida, Hikaru Takatori, Kosuke Sato, and Kenji Suzuki. 2015.
CHILDHOOD. In ACM SIGGRAPH 2015 Emerging Technologies. ACM
Press, New York, New York, USA, 1–1. https://doi.org/10.1145/2782782.
2792501[25] Jun Nishida, Hikaru Takatori, Kosuke Sato, and Kenji Suzuki. 2015.
CHILDHOOD. In the 2015 Virtual Reality International Conference.
ACM Press, New York, New York, USA, 1–4. https://doi.org/10.1145/
2806173.2806190[26] Mariella Pazzaglia and Marco Molinari. 2016. The embodiment ofassistive devices—from wheelchair to exoskeleton. Physics of life
reviews 16 (March 2016), 163–175. https://doi.org/10.1016/j.plrev.2015.
11.006[27] B Philippe, D Gonzalez-Franco, A Pointeau, C Cherene Prix Ars Electronica, and 2014. [n. d.]. The Machine to be Another-Embodied Telepresence using human performers. http://scholar.google.comjavascript:
void(0)[28] Gastone Pietro Rosati Papini, Marco Fontana, and Massimo Bergamasco. 2016. Desktop Haptic Interface for Simulation of HandTremor. IEEE Transactions on Haptics 9, 1 (Jan. 2016), 33–42. https://doi.org/10.1109/TOH.2015.2504971[29] Hiroka Sabu, Tomoyo Morita, Hideyuki Takahashi, Eiichi Naito, andMinoru Asada. 2018. Being a leader in a rhythmic interaction activates
reward-related brain regions. Neuroscience Research (Aug. 2018), 1–7.
https://doi.org/10.1016/j.neures.2018.08.009[30] MHD Yamen Saraiji, Tomoya Sasaki, Reo Matsumura, Kouta Minamizawa, and Masahiko Inami. 2018. Fusion. In ACM SIGGRAPH
2018 Emerging Technologies. ACM Press, New York, New York, USA,
1–2. https://doi.org/10.1145/3214907.3214912[31] Ida Shino and Yamanaka Toshimasa. 2000. A study on the usabilityof environment objects by the di�erence in eye level (In Japanese). In
Japan Society of the Science of Design.
[32] Susumu Tachi, Kouichi Watanabe, Keisuke Takeshita, Kouta Minamizawa, Takumi Yoshida, and Katsunari Sato. 2011. Mutual Telexistence Surrogate System - TELESAR4 - telexistence in real environments using autostereoscopic immersive display. IROS (2011), 157–162.
https://doi.org/10.1109/IROS.2011.6094543[33] Björn van der Hoort, Arvid Guterstam, and H Henrik Ehrsson. 2011.
Being Barbie: The Size of One’s Own Body Determines the Perceived
Size of the World. PLoS ONE 6, 5 (May 2011), e20195–10. https://doi.org/10.1371/journal.pone.0020195

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