O que causa Spatial Presence?
Estímulos Sensoriais (Steuer)
De acordo com Steuer (1992) Spatial Presence constrói-se sobre duas propriedade de um media: Vividness e Interactivity.
Vividness trata-se da representação rica do ambiente retratado no media no que toca aos sentidos - quantos mais sentidos forem capturados e quanto mais saturados com reproduções mais semelhantes à realidade, maior será a Spatial Presence do utilizador.
"Steuer understands vividness as “the representational richness of a mediated environment as defi ned by its formal features, that is, the way in which an environment presents information to the senses ” (...). In general, the more different senses a media system addresses (visual, auditive, haptical senses, etc.…), the higher the breadth of its vividness. The more each sensory channel is occupied by stimuli generated by the media system as opposed to the physical environment, the stronger is the “saturation of the sensory channels engaged” (...), and the more intense is the vividness provided by a media system.(...)
But a high breadth and intensity of sensory channels stimulated by a media environment is not necessarily sufficient to foster Spatial Presence. According to Steuer, the decisive characteristics of media system’s vividness eventually is the “sensory fi delity […] within each sensory channel”"
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Interactivity relaciona-se com o modo em que o utilizador afeta o sistema e o quão realistas são as possibilidades de interação e o feedback.
"The second property of a media system that Steuer ( 1992 ) regards as a determinant of Spatial Presence is interactivity. Interactivity is defined “as the extent to which users can participate in modifying the form and content of a mediated environment in real time” (p. 4). According to Steuer, the interactive capabilities of a media system vary by “the rate at which [a user’s] input can be assimilated in the mediated
environment” (“speed”, p. 4), by “the number of possibilities for action at any given time” (“range”, p. 4), and, probably most importantly, by the ability of the system to map the user’s input in a natural manner (“mapping”, p. 4)."
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Imersão e Estado Binário (Slater)
Slater (1994) parte do conceito de Spatial Presence como determinado pela imersão do utilizador. A imersão é alta se o utilizador for capaz de se projetar egocêntricamente dentro do ambiente, significando que se consegue colocar no local da personagem, tem vista de primeira pessoa.
"Spatial Presence entails “a state of consciousness, the (psychological) sense of being in the virtual environment, and
corresponding modes of behaviour” (...). This psychological state is considered to be the corollary of an immersive virtual environment. An environment is considered immersive, if it provides an optimal match between the displayed sensory data and the user’s proprioception (...).
(...)Users immersed in the virtual environment are likely to
identify with their virtual body, as they can engage in an egocentric frame of reference so that their self-representation in the media scenery coincides with the viewpoint from which the virtual world is experienced (...). That implies that the immersive potential of a medium is high, if the application allows
for a successful implementation of the user’s egocentric reference frame into the mediated scenery."
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Noutro ponto, Slater (2000) sugere que o utilizador recebe spatial signals de dois ambientes opostos - o real e o virtual - e, para manter Spacial Presence, igonora o estímulo que não lhe é relevante. Como o mundo real pode causar distrações, prevê a existência de breaks in presence em que a fonte de estímulo se altera, sendo então Spatial Presence vista como um estado binário
"The main idea of the approach is that media users receive spatial signals from different and often competing environments – the real environment and the media environment – which they have to assemble in a consistent cognitive Gestalt. Users may continuously shift their attentional resources towards the specifi c signals belonging to the virtual or real world. Depending on which of the data streams they primarily rely on to interpret a situation in a given moment, their referring spatial Gestalt may correspond more to the world portrayed by the media environment or to the real world. For the sake of consistency, “sensory data correspon-ding to the non-favored interpretation may be ignored, or incorporated into the prevailing Gestalt”.(...)If
users primarily rely on data from the virtual environment to build their spatial “Gestalt”, they may experience Spatial Presence. However, if they rely on the data stream from the real world, the feeling of being in the virtual world may be lost.
With the users’ attentional focus permanently switching between the real and the virtual world, a constant transition between feeling spatially present in the one or the other environment might occur. Slater and colleagues termed this transition “breaks in presence”: “A break in presence (BIP) is the moment of switch between responding to signals with source in environment X to those with source in environment Y.(...)""
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Atenção (Draper)
De acordo com Draper (1998) a sensação de Spacial Presence surge quando a atenção do utilizador está totalmente dedicada ao meio tecnológico enquanto o mundo real é ignorado.
"If a user encounters a mediated environment, the depicted spatial scenery may challenge the actual reference system of the user (...). It might be argued that the media system competes with the actual environment of the user for controlling his or her senses – in order to induce their “spatial logic” and to override the existing spatial reference system of the user. (...)According to Draper et al., attention is a key component of Spatial Presence formation, as it may direct users’ sensory perception to mediated stimuli and away from cues provided by the real environment. Draper et al. are not specific about the information that needs to be processed by the user, but consider attention to be suffi cient to evoke Spatial Presence: “When attentional resources are totally committed to the computer mediated environment, the user will report a strong sense of telepresence”"
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Cognição Incorporada (Schubert)
Segundo Schubert (1999) Spatial Presence é uma sensação provocada pela "cognição incorporada" do utilizador, isto significa que provém das possibilidades de ação com o ambiente e a capacidade de prever tais ações.
"According to Schubert et al., users of virtual environments mentally model the action possibilities they perceive in a virtual environment. In contrast to mere spatial models or a spatial Gestalt, those representations may be addressed as embodied
mental models that build on perceptions of the own body, its position in the room, and related possible actions. “They are spatial-functional models, not purely spatial models” (...). Following the conceptualization, the more stimuli from the real
world are suppressed, and the more natural the feedback of a virtual environment that follows onto any conducted action, the easier the construction of an embodied mental model is supposed to be. An embodied mental model, once constructed, is supposed to immediately trigger a feeling of Spatial Presence. Accordingly, Schubert et al.’s central idea is that “[Spatial] presence develops from the cognitive representation of possible actions that can be performed in the virtual world”(...)."
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Perceção Cognitiva e Imersão (Wirth)
De acordo com o modelo de dois níveis de Wirth (2007), o primeiro nível de Spatial Presence constitui-se pela projeção de um spatial situation model do ambiente do media de acordo com a perceção do sujeito que é continuamente adaptado e cresce em complexidade com a quantidade de estímulos recebidos.
"According to the fi rst level of the model, users – after
allocating their attention to the media stimulus – construct a spatial situation model of the media environment (...). The spatial situation model is simply understood as a cognitive representa-
tion of the spatial scenery depicted by an environment, similar to Slater’s (...) notion of a spatial Gestalt. Its formation involves processes of subjective construction and interpretation(...)
According to the Two-Level Model, the spatial situation model is expected to be more detailed and comprehensive, the more spatial cues the medium offers and the more attentive and motivated users are (...). In addition, cognitive abilities of users like their spatial visual imagery skills are thought to support
the formation of a spatial situation model.
(...)a spatial situation model is a mere mental representation of the spatial logic provided by an environment. A photo or a postcard may already evoke a spatial situation model. Such a
model is not equivalent to the way users understand their actual spatial surrounding; it only provides an alternative interpretation of what the actual surrounding may be."
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O segundo nível nasce quando o estímulo é complexo o suficiente para o sujeito ter que se focar unicamente no mundo mediado e a lógica de posicionamento espacial se altera para lhe corresponder, alterando-se o corpo de referência do sujeito e surgindo a sensação de Spatial Presence.
"The second level of the Two-Level Model by Wirth et al. (2007) conceptualizes this “struggle” between users’ prevalent interpretation of their spatial surrounding and the new and competing information provided by the media-bound spatial situation model.
According to the Two-Level Model, on the second level of Spatial Presence formation, users unconsciously choose a Primary Egocentric Reference Frame, i.e., they start to either believe in the spatial surrounding of the real or the mediated
environment, depending on if they follow the logic of the spatial situation model of the real world or the one of the media environment.(...)"
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É importante notar que o sucesso da criação de Spatial Presence não é só determinado pelas condições do media, mas também pelas característi-
cas do utilizador, tais como o seu envolvimento emocional, a suspensão de descrença (eliminação voluntária de informação que contradiz a realidade como glitches ou gráficos de baixa qualidade) e a sua motivação ao lidar com tarefas.
"(...)insufficient spatial cues of the media environment (for example a book scenario) maybe counteracted by users’ traits and actions. Specifically, user’s absorption, involvement, and suspension of disbelief are considered to be relevant with regard to the test of perceptual hypotheses (...)."
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"Feelings of emotions (and thus emotional involvement) motivate or urgeindividuals to direct their mental activities to the emotion-eliciting event (...). If a mediated environment contains various features inducing emotional involvement, then individuals are likely to focus their mental activities on the emotional media stimulus that caused their current state. As a consequence, the subjective perception of being in and acting within the mediated environment will be fostered, whereas any alternative perception will be weakened. More precisely, the perception of the self being located within the mediated environment will become more likely. This should result in more intense or more frequent feelings of spatial presence(...)."
The Role of Emotional Involvement and
Trait Absorption in the Formation of Spatial Presence
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Gestalt Psychology em Wikipédia
Even Though You Know it is an Illusion... blog by Mel Slater
Defining Virtual Reality: Dimensions Determining Telepresence por Jonathan Steuer
Spatial Presence Theory:State of The Art and Challenges Ahead por Tilo Hartmann e outros
The Role of Emotional Involvement and Trait Absorption in the Formation of Spatial Presence por Werner Wirth e Matthias Hofer