Eva Waterworth | Umeå University (original) (raw)

Papers by Eva Waterworth

Research paper thumbnail of Intention, Action, Self and Other: An Evolutionary Model of Presence

Springer eBooks, 2015

The term “presence” entered in the wide scientific debate in 1992 when Sheridan and Furness used ... more The term “presence” entered in the wide scientific debate in 1992 when Sheridan and Furness used it in the title of a new journal dedicated to the study of virtual reality systems and teleoperations: Presence, Teleoperators and Virtual Environments. Following this approach, the term “presence” has been used to describe a widely re-ported sensation experienced during the use of virtual reality. The main limitation of this vision is what is not said. What is presence for? Is it a specific cognitive process? To answer to these questions, a second group of researchers considers presence as a broad psychological phenomenon, not necessarily linked to the experience of a medium, whose goal is the control of the individual and social activity. In this chapter we support this second vision, starting from the following broad statements: (a) the psychology of presence is related to human action and its organization in the environment; (b) the psychology of presence is related to the body and to the embodiment process; (c) presence is an evolved process related to the understanding and management of the causal texture of both the physical and social worlds. In the following paragraphs we will justify these claims and underline their relevance for the design and usage of interactive technologies.

Research paper thumbnail of In tent, in touch

CHI '01 extended abstracts on Human factors in computer systems - CHI '01, 2001

We describe The Tent, an immersive environment designed to stimulate creativity and to support no... more We describe The Tent, an immersive environment designed to stimulate creativity and to support non-symbolic communication. In a tent we are secluded but also in touch, with nature and with ourselves. We are experimenting with the Tent as a meditative, relaxing environment, but also as a stimulating one, and as a medium for non-symbolic communication.

Research paper thumbnail of Relaxation Island : A Virtual Tropical Paradise. Interactive Experience

We present Relaxation Island, one of several Mood Devices we have developed with our partners as ... more We present Relaxation Island, one of several Mood Devices we have developed with our partners as part of the EMMA (Engaging Media for Mental Health Applications) project. Mood Devices are interactive digital media and environments designed to alter the inter-actor's psychological state. Relaxation Island was designed to support established relaxation techniques, as part of interventions to assist individuals cope with specific anxieties such as examination stress, and also simply as a virtual place where anyone can go to relax. Attendees of this interactive experience will have the opportunity to relax on the island, navigating around the virtual space using a novel wireless "seashell" device

Research paper thumbnail of ELITE design : IT for the elderly

ub.umu.se. Publications. ...

Research paper thumbnail of The illusion of being present: Using the interactive tent to create immersive experiences

We describe a novel immersive environment -- the Interactive Tent -- and an artistic production w... more We describe a novel immersive environment -- the Interactive Tent -- and an artistic production within it -- The Illusion of Being. In this production, immersants experience a vivid cycle of the seasons in a way that depends on their bodily movements. Everybody's experience of ...

Research paper thumbnail of Eyes Open or Closed: is a virtual beach more relaxing than an imagined beach?

This paper describes a virtual reality (VR) island that has recently been developed within the EM... more This paper describes a virtual reality (VR) island that has recently been developed within the EMMA Project to induce relaxed mood states. The island is designed to augment standard relaxation techniques such as progressive muscular relaxation and breathing techniques. The effectiveness of such techniques may usually depend on an individual's ability to visualise relaxing scenarios, but the VR island brings a relaxing island into a user's perceived reality and users are taught a variety of adapted procedures to elicit a state of calm. Users can explore the island using a wireless "seashell" with a pearl as the navigation tool. Different zones on the island have specific visuals, narratives and biofeedback to relax the user. For example, in the beach zone the user learns relaxed breathing as the narrative reminds her to take slow deep breaths and to be in the moment. The body joystick, a sensor-based device for measuring chest expansion, responds to the user's b...

Research paper thumbnail of What Do Elderly Users Want and Need from Fitness Technologies?

Integrating Technology in Positive Psychology Practice

It is well known that physical exercise has a significant beneficial effect on mental and physica... more It is well known that physical exercise has a significant beneficial effect on mental and physical health, and elderly fitness programs are a good and widely accepted approach to prevent frailty. In this chapter, we examine what elderly people actually want and need when it comes to technologies designed to support and encourage their physical fitness. We present the ELF@Home project as a case study, and report design insights and other results from user involvement in the project. User involvement is a key component of the approach and uses methods such as interviews, focus group meetings, early component and prototype tests with users, as well as inputs from medical experts. ELF@Home is a clear example of a “Positive Technology” approach. The project proposes the adoption of new technology in everyday life from the perspective of positive psychology, approaching this aim by designing devices and systems that are actually usable and desirable in supporting extended healthy living f...

Research paper thumbnail of N�rvarande ledam�ter

Research paper thumbnail of The role of ICT and networking in healthy ageing

Proceedings of the 5th International Conference on PErvasive Technologies Related to Assistive Environments - PETRA '12, 2012

Research paper thumbnail of Seniors in charge of ICT innovation

Proceedings of the 5th International Conference on PErvasive Technologies Related to Assistive Environments - PETRA '12, 2012

We present the user-driven AGNES project (aal-2008-1-014). The project has three user groups, one... more We present the user-driven AGNES project (aal-2008-1-014). The project has three user groups, one in each of Sweden, Spain and Greece, who have participated as full members of the project team. The method used for developing this novel ICT was an extension of the ELITE design approach for user driven innovation. The results presented in the paper are on how the users' attitudes changed during the project due to their having the expert role in the development process and how they accepted and acted in that role. To start with, the elderly users were very polite, often negative about and frightened of technology. Some did not have a computer of their own and did not have any or much experiences of new communication technologies. During the project the users were introduced to an interactive social network, generated design ideas for new ICT and also tested ICT solutions related to using the social network and connected devices. The paper gives examples of how the user attitudes towards technology changes during the project and discusses how they became true experts able to express their knowledge and in that way exert control over the technical design in the project. The result is that the users have become bold, good at expressing their knowledge, and good at marketing the project and the use of technology to other people, and in the process increasing their social life both on the net and in the physical world.

Research paper thumbnail of Virtual reality to reduce anxiety in healthy population: The Relaxation Island

PsycEXTRA Dataset

ub.umu.se. Publications. ...

Research paper thumbnail of Transnational Comparison: A Retrospective Study on e-Health in Sparsely Populated Areas of the Northern Periphery

Telemedicine and e-Health, 2010

Healthcare delivery in the northern periphery of Europe is challenged by dispersed populations, g... more Healthcare delivery in the northern periphery of Europe is challenged by dispersed populations, geographical complexities (including mountainous terrain and inhabited islands), ageing populations, and rising patient expectations. It is challenged further by variations in transport networks and information communication technology infrastructure. This article provides an overview of e-health development across the northern periphery areas of four northern European countries (Finland, Sweden, Norway, and Scotland) by summarizing the outcomes of a mixed methods e-health mapping exercise and subsequently identifying service needs and gaps. A total of 148 applications, with a range of applied ehealth solutions, were identified and the findings have promoted the sharing and transfer of e-health innovation across the four countries. The supporting telecommunications infrastructure and development of innovative telemedicine appear slower in sparsely populated areas of Scotland in comparison to its northern peripheral counterparts. All four countries have, however, demonstrated a clear commitment to the development of e-health within their remote and rural regions.

Research paper thumbnail of The e-health implementation toolkit: qualitative evaluation across four European countries

Implementation science : IS, Jan 19, 2011

Background: Implementation researchers have attempted to overcome the research-practice gap in e-... more Background: Implementation researchers have attempted to overcome the research-practice gap in e-health by developing tools that summarize and synthesize research evidence of factors that impede or facilitate implementation of innovation in healthcare settings. The e-Health Implementation Toolkit (e-HIT) is an example of such a tool that was designed within the context of the United Kingdom National Health Service to promote implementation of e-health services. Its utility in international settings is unknown. Methods: We conducted a qualitative evaluation of the e-HIT in use across four countries-Finland, Norway, Scotland, and Sweden. Data were generated using a combination of interview approaches (n = 22) to document e-HIT users' experiences of the tool to guide decision making about the selection of e-health pilot services and to monitor their progress over time. Results: e-HIT users evaluated the tool positively in terms of its scope to organize and enhance their critical thinking about their implementation work and, importantly, to facilitate discussion between those involved in that work. It was easy to use in either its paper-or web-based format, and its visual elements were positively received. There were some minor criticisms of the e-HIT with some suggestions for content changes and comments about its design as a generic tool (rather than specific to sites and e-health services). However, overall, e-HIT users considered it to be a highly workable tool that they found useful, which they would use again, and which they would recommend to other e-health implementers. Conclusion: The use of the e-HIT is feasible and acceptable in a range of international contexts by a range of professionals for a range of different e-health systems.

Research paper thumbnail of Bone density and size in ambulatory children with cerebral palsy

Developmental Medicine & Child Neurology, 2010

CSA Cross-sectional area DXA Dual energy X-ray absorptiometry QCT Quantitative computed tomograph... more CSA Cross-sectional area DXA Dual energy X-ray absorptiometry QCT Quantitative computed tomography vBMD Volumetric cancellous bone density AIM To examine the relation of axial and appendicular bone properties in ambulatory children with cerebral palsy (CP) to functional (Gross Motor Function Classification System [GMFCS]) level. METHOD Quantitative computed tomography measurements were compared among 37 children with CP (12 children in GMFCS level I, five in level II, 18 in level III, two in level IV; five with hemiplegia, 23 with diplegia, two with triplegia, seven with quadriplegia; mean age 9y 4mo, SD 1y 6mo; 18 males, 19 females) and 37 children in a comparison group (same age and sex distributions). Linear regression was used to evaluate differences in volumetric cancellous bone density (vBMD) and geometric properties of the L3 vertebra and tibia, adjusting for height, weight, and sex as covariates. RESULTS The comparison group had larger vertebrae than the children with CP (p=0.02) owing to smaller vertebral size in GMFCS levels III and IV, but there was no difference in vertebral vBMD (p=0.49). In the tibia, bone volumetric density (p=0.09) and size (p=0.02) decreased with increasing GMFCS level. GMFCS level had a greater effect on bone size in females than in males (p<0.07).

Research paper thumbnail of Presence and Absence in Education VR

Citeseer

Recently developed information technology, such as interactive multimedia and virtual reality, ha... more Recently developed information technology, such as interactive multimedia and virtual reality, has a profound impact the way people deal with information. Often, they engender a strong feeling of presence, of being an active part of the reality that is portrayed. It is this feeling of presence that differentiates the new learning technologies from the old; and it is this same feeling of presence which is both their greatest strength and their most severe weakness. In this paper, we discuss the respective roles of presence and also of ...

Research paper thumbnail of Perceptually Seductive Communication (PSC)-a primordial way to communicate through technology

4th Swedish Symposium on Multimodal Communication, Oct 1, 2000

Most of our communication today is carried out linguistically, both between humans and between hu... more Most of our communication today is carried out linguistically, both between humans and between human and machine. We define linguistic communication as communication using an abstract language, such as speech and written languages (see figure 1a). Perceptually Seductive Communication (PSC) on the other hand (see figure 1b), implies a return to a more basic and primitive way of communication (and of being; Waterworth, 1998). PSC refers to a multimodal communication that uses several senses at the same time, leading ...

Research paper thumbnail of Presence and absence in educational VR: the role of perceptual seduction in conceptual learning

Themes in Education, 2000

Research paper thumbnail of Presence as a dimension of communication: Context of use and the person

From communication to presence: Cognition, emotions and culture towards the ultimate communicative experience, 2006

Abstract. We claim that presence is elicited most strongly when information is presented as an in... more Abstract. We claim that presence is elicited most strongly when information is presented as an inhabitable, external world. Technical developments that permit this, such as the creation of interactive, immersive virtual environments herald a profound change in how people relate to sources of information, and how they communicate. This change has psychological, social and cultural effects. It has been claimed that in many ways, our relationship to information becomes that of our ancestral, pre-literate relationship to the physical world. ...

Research paper thumbnail of The core of presence: Presence as perceptual illusion

Presence Connect, Jul 1, 2003

Research paper thumbnail of On feeling (the) present: An evolutionary account of the sense of presence in physical and electronically-mediated environments

Journal of consciousness studies, 2010

The sense of presence is the ability to experience the fact that one is physically present in the... more The sense of presence is the ability to experience the fact that one is physically present in the place in which the body is currently located. In other words, it refers to the part of the contents of consciousness that relate to the current time and place in which the body is located. We present an account of the sense of presence understood as the result of an evolved neuropsychological process, created through the evolution of the central nervous system, and which solves a key problem for an organism's survival: how to differentiate ...

Research paper thumbnail of Intention, Action, Self and Other: An Evolutionary Model of Presence

Springer eBooks, 2015

The term “presence” entered in the wide scientific debate in 1992 when Sheridan and Furness used ... more The term “presence” entered in the wide scientific debate in 1992 when Sheridan and Furness used it in the title of a new journal dedicated to the study of virtual reality systems and teleoperations: Presence, Teleoperators and Virtual Environments. Following this approach, the term “presence” has been used to describe a widely re-ported sensation experienced during the use of virtual reality. The main limitation of this vision is what is not said. What is presence for? Is it a specific cognitive process? To answer to these questions, a second group of researchers considers presence as a broad psychological phenomenon, not necessarily linked to the experience of a medium, whose goal is the control of the individual and social activity. In this chapter we support this second vision, starting from the following broad statements: (a) the psychology of presence is related to human action and its organization in the environment; (b) the psychology of presence is related to the body and to the embodiment process; (c) presence is an evolved process related to the understanding and management of the causal texture of both the physical and social worlds. In the following paragraphs we will justify these claims and underline their relevance for the design and usage of interactive technologies.

Research paper thumbnail of In tent, in touch

CHI '01 extended abstracts on Human factors in computer systems - CHI '01, 2001

We describe The Tent, an immersive environment designed to stimulate creativity and to support no... more We describe The Tent, an immersive environment designed to stimulate creativity and to support non-symbolic communication. In a tent we are secluded but also in touch, with nature and with ourselves. We are experimenting with the Tent as a meditative, relaxing environment, but also as a stimulating one, and as a medium for non-symbolic communication.

Research paper thumbnail of Relaxation Island : A Virtual Tropical Paradise. Interactive Experience

We present Relaxation Island, one of several Mood Devices we have developed with our partners as ... more We present Relaxation Island, one of several Mood Devices we have developed with our partners as part of the EMMA (Engaging Media for Mental Health Applications) project. Mood Devices are interactive digital media and environments designed to alter the inter-actor's psychological state. Relaxation Island was designed to support established relaxation techniques, as part of interventions to assist individuals cope with specific anxieties such as examination stress, and also simply as a virtual place where anyone can go to relax. Attendees of this interactive experience will have the opportunity to relax on the island, navigating around the virtual space using a novel wireless "seashell" device

Research paper thumbnail of ELITE design : IT for the elderly

ub.umu.se. Publications. ...

Research paper thumbnail of The illusion of being present: Using the interactive tent to create immersive experiences

We describe a novel immersive environment -- the Interactive Tent -- and an artistic production w... more We describe a novel immersive environment -- the Interactive Tent -- and an artistic production within it -- The Illusion of Being. In this production, immersants experience a vivid cycle of the seasons in a way that depends on their bodily movements. Everybody's experience of ...

Research paper thumbnail of Eyes Open or Closed: is a virtual beach more relaxing than an imagined beach?

This paper describes a virtual reality (VR) island that has recently been developed within the EM... more This paper describes a virtual reality (VR) island that has recently been developed within the EMMA Project to induce relaxed mood states. The island is designed to augment standard relaxation techniques such as progressive muscular relaxation and breathing techniques. The effectiveness of such techniques may usually depend on an individual's ability to visualise relaxing scenarios, but the VR island brings a relaxing island into a user's perceived reality and users are taught a variety of adapted procedures to elicit a state of calm. Users can explore the island using a wireless "seashell" with a pearl as the navigation tool. Different zones on the island have specific visuals, narratives and biofeedback to relax the user. For example, in the beach zone the user learns relaxed breathing as the narrative reminds her to take slow deep breaths and to be in the moment. The body joystick, a sensor-based device for measuring chest expansion, responds to the user's b...

Research paper thumbnail of What Do Elderly Users Want and Need from Fitness Technologies?

Integrating Technology in Positive Psychology Practice

It is well known that physical exercise has a significant beneficial effect on mental and physica... more It is well known that physical exercise has a significant beneficial effect on mental and physical health, and elderly fitness programs are a good and widely accepted approach to prevent frailty. In this chapter, we examine what elderly people actually want and need when it comes to technologies designed to support and encourage their physical fitness. We present the ELF@Home project as a case study, and report design insights and other results from user involvement in the project. User involvement is a key component of the approach and uses methods such as interviews, focus group meetings, early component and prototype tests with users, as well as inputs from medical experts. ELF@Home is a clear example of a “Positive Technology” approach. The project proposes the adoption of new technology in everyday life from the perspective of positive psychology, approaching this aim by designing devices and systems that are actually usable and desirable in supporting extended healthy living f...

Research paper thumbnail of N�rvarande ledam�ter

Research paper thumbnail of The role of ICT and networking in healthy ageing

Proceedings of the 5th International Conference on PErvasive Technologies Related to Assistive Environments - PETRA '12, 2012

Research paper thumbnail of Seniors in charge of ICT innovation

Proceedings of the 5th International Conference on PErvasive Technologies Related to Assistive Environments - PETRA '12, 2012

We present the user-driven AGNES project (aal-2008-1-014). The project has three user groups, one... more We present the user-driven AGNES project (aal-2008-1-014). The project has three user groups, one in each of Sweden, Spain and Greece, who have participated as full members of the project team. The method used for developing this novel ICT was an extension of the ELITE design approach for user driven innovation. The results presented in the paper are on how the users' attitudes changed during the project due to their having the expert role in the development process and how they accepted and acted in that role. To start with, the elderly users were very polite, often negative about and frightened of technology. Some did not have a computer of their own and did not have any or much experiences of new communication technologies. During the project the users were introduced to an interactive social network, generated design ideas for new ICT and also tested ICT solutions related to using the social network and connected devices. The paper gives examples of how the user attitudes towards technology changes during the project and discusses how they became true experts able to express their knowledge and in that way exert control over the technical design in the project. The result is that the users have become bold, good at expressing their knowledge, and good at marketing the project and the use of technology to other people, and in the process increasing their social life both on the net and in the physical world.

Research paper thumbnail of Virtual reality to reduce anxiety in healthy population: The Relaxation Island

PsycEXTRA Dataset

ub.umu.se. Publications. ...

Research paper thumbnail of Transnational Comparison: A Retrospective Study on e-Health in Sparsely Populated Areas of the Northern Periphery

Telemedicine and e-Health, 2010

Healthcare delivery in the northern periphery of Europe is challenged by dispersed populations, g... more Healthcare delivery in the northern periphery of Europe is challenged by dispersed populations, geographical complexities (including mountainous terrain and inhabited islands), ageing populations, and rising patient expectations. It is challenged further by variations in transport networks and information communication technology infrastructure. This article provides an overview of e-health development across the northern periphery areas of four northern European countries (Finland, Sweden, Norway, and Scotland) by summarizing the outcomes of a mixed methods e-health mapping exercise and subsequently identifying service needs and gaps. A total of 148 applications, with a range of applied ehealth solutions, were identified and the findings have promoted the sharing and transfer of e-health innovation across the four countries. The supporting telecommunications infrastructure and development of innovative telemedicine appear slower in sparsely populated areas of Scotland in comparison to its northern peripheral counterparts. All four countries have, however, demonstrated a clear commitment to the development of e-health within their remote and rural regions.

Research paper thumbnail of The e-health implementation toolkit: qualitative evaluation across four European countries

Implementation science : IS, Jan 19, 2011

Background: Implementation researchers have attempted to overcome the research-practice gap in e-... more Background: Implementation researchers have attempted to overcome the research-practice gap in e-health by developing tools that summarize and synthesize research evidence of factors that impede or facilitate implementation of innovation in healthcare settings. The e-Health Implementation Toolkit (e-HIT) is an example of such a tool that was designed within the context of the United Kingdom National Health Service to promote implementation of e-health services. Its utility in international settings is unknown. Methods: We conducted a qualitative evaluation of the e-HIT in use across four countries-Finland, Norway, Scotland, and Sweden. Data were generated using a combination of interview approaches (n = 22) to document e-HIT users' experiences of the tool to guide decision making about the selection of e-health pilot services and to monitor their progress over time. Results: e-HIT users evaluated the tool positively in terms of its scope to organize and enhance their critical thinking about their implementation work and, importantly, to facilitate discussion between those involved in that work. It was easy to use in either its paper-or web-based format, and its visual elements were positively received. There were some minor criticisms of the e-HIT with some suggestions for content changes and comments about its design as a generic tool (rather than specific to sites and e-health services). However, overall, e-HIT users considered it to be a highly workable tool that they found useful, which they would use again, and which they would recommend to other e-health implementers. Conclusion: The use of the e-HIT is feasible and acceptable in a range of international contexts by a range of professionals for a range of different e-health systems.

Research paper thumbnail of Bone density and size in ambulatory children with cerebral palsy

Developmental Medicine & Child Neurology, 2010

CSA Cross-sectional area DXA Dual energy X-ray absorptiometry QCT Quantitative computed tomograph... more CSA Cross-sectional area DXA Dual energy X-ray absorptiometry QCT Quantitative computed tomography vBMD Volumetric cancellous bone density AIM To examine the relation of axial and appendicular bone properties in ambulatory children with cerebral palsy (CP) to functional (Gross Motor Function Classification System [GMFCS]) level. METHOD Quantitative computed tomography measurements were compared among 37 children with CP (12 children in GMFCS level I, five in level II, 18 in level III, two in level IV; five with hemiplegia, 23 with diplegia, two with triplegia, seven with quadriplegia; mean age 9y 4mo, SD 1y 6mo; 18 males, 19 females) and 37 children in a comparison group (same age and sex distributions). Linear regression was used to evaluate differences in volumetric cancellous bone density (vBMD) and geometric properties of the L3 vertebra and tibia, adjusting for height, weight, and sex as covariates. RESULTS The comparison group had larger vertebrae than the children with CP (p=0.02) owing to smaller vertebral size in GMFCS levels III and IV, but there was no difference in vertebral vBMD (p=0.49). In the tibia, bone volumetric density (p=0.09) and size (p=0.02) decreased with increasing GMFCS level. GMFCS level had a greater effect on bone size in females than in males (p<0.07).

Research paper thumbnail of Presence and Absence in Education VR

Citeseer

Recently developed information technology, such as interactive multimedia and virtual reality, ha... more Recently developed information technology, such as interactive multimedia and virtual reality, has a profound impact the way people deal with information. Often, they engender a strong feeling of presence, of being an active part of the reality that is portrayed. It is this feeling of presence that differentiates the new learning technologies from the old; and it is this same feeling of presence which is both their greatest strength and their most severe weakness. In this paper, we discuss the respective roles of presence and also of ...

Research paper thumbnail of Perceptually Seductive Communication (PSC)-a primordial way to communicate through technology

4th Swedish Symposium on Multimodal Communication, Oct 1, 2000

Most of our communication today is carried out linguistically, both between humans and between hu... more Most of our communication today is carried out linguistically, both between humans and between human and machine. We define linguistic communication as communication using an abstract language, such as speech and written languages (see figure 1a). Perceptually Seductive Communication (PSC) on the other hand (see figure 1b), implies a return to a more basic and primitive way of communication (and of being; Waterworth, 1998). PSC refers to a multimodal communication that uses several senses at the same time, leading ...

Research paper thumbnail of Presence and absence in educational VR: the role of perceptual seduction in conceptual learning

Themes in Education, 2000

Research paper thumbnail of Presence as a dimension of communication: Context of use and the person

From communication to presence: Cognition, emotions and culture towards the ultimate communicative experience, 2006

Abstract. We claim that presence is elicited most strongly when information is presented as an in... more Abstract. We claim that presence is elicited most strongly when information is presented as an inhabitable, external world. Technical developments that permit this, such as the creation of interactive, immersive virtual environments herald a profound change in how people relate to sources of information, and how they communicate. This change has psychological, social and cultural effects. It has been claimed that in many ways, our relationship to information becomes that of our ancestral, pre-literate relationship to the physical world. ...

Research paper thumbnail of The core of presence: Presence as perceptual illusion

Presence Connect, Jul 1, 2003

Research paper thumbnail of On feeling (the) present: An evolutionary account of the sense of presence in physical and electronically-mediated environments

Journal of consciousness studies, 2010

The sense of presence is the ability to experience the fact that one is physically present in the... more The sense of presence is the ability to experience the fact that one is physically present in the place in which the body is currently located. In other words, it refers to the part of the contents of consciousness that relate to the current time and place in which the body is located. We present an account of the sense of presence understood as the result of an evolved neuropsychological process, created through the evolution of the central nervous system, and which solves a key problem for an organism's survival: how to differentiate ...