1 Introduction

Thanks to rapid advancements in technology and software, digital virtual environments (DVEs) have become a common aspect of modern life. A DVE is a synthetic environment that is generated via digital technology that users perceive as non-synthetic (e.g., Loomis et al. 1999). In past decades, production of such environments was limited to mainframe and minicomputers that required skilled programmers to create. Now, such environments can be accessed by a large audience and generated with greater ease as a result of free software such as Unity and Blender.

While DVEs vary in quality, a key component of any good DVE is that it immerses the user and allows them to experience the psychological phenomena of presence (Bowman and McMahan 2007). Immersion refers to the technological quality of the media, which partially determines the degree of presence (the sense of “being there” in the virtual world) experienced by users (Cummings and Bailenson 2016). Increased presence is thought to magnify user effects, which is the extent a user’s behavior in the DVE reflects their behavior in the physical world (Slater et al. 1996). In addition, higher presence enhances the effectiveness of a DVE, such as in entertainment or therapeutic applications (Klimmt and Vorderer 2003; Krijn et al. 2004). Importantly, presence in a DVE can be experienced via a range of devices, ranging from relatively non-immersive smart phones, to desktop computers, to immersive head-mounted displays (HMDs; Blascovich and Bailenson 2011). Yet the less immersive a system is, the more the additional mental recreation is required for the user to believe that they are present in the DVE (Slater 2009). In both applied and academic work, achieving high levels of immersion and presence in DVEs is a central goal (Cummings and Bailenson 2016).

Seeing as how presence is a subjective phenomenon, a common approach to measure it is to use a questionnaire after the end of the experimental procedure (Ijsselsteijn et al. 2000). Posttest questionnaires are easy to administer and do not disrupt the virtual experience. However, they have been critiqued for their inability to compare experiences across different modalities (Usoh et al. 2000), which presents interpretational difficulties when assessing presence scores from immersive virtual experiences, compared to desktop ones. Nonetheless, presence has been and continues to be measured with questionnaires (Barfield 2016); hence, for this study, questionnaires are employed to measure the variables of interest, specifically the various aspects of presence, immersion, and reality judgment.

The goal of the present study is to investigate the effects of starting a digital virtual experience in an environment that is a replica of the immediate physical environment.

2 Background

Although numerous studies cited above had emphasized the role of high-fidelity technology in creating a sense of presence in a DVE, sophisticated technological hardware is only part of what creates the phenomenon of presence. In the pioneering work by Slater et al. (1998), it was suggested that presence in a DVE can be increased by using a transitional DVE. In the study, participants started a virtual reality experience in a replica of their immediate physical environment. Participants started the experiment by being trained in a task in the physical laboratory and then doing the same task in a replicated virtual environment with a HMD that tracked body and head movements. After training, participants entered a field, which was connected to the laboratory by a door and completed the experimental part of the procedure. Although the authors speculated that use of a digitally replicated physical space could enhance presence, the effect of such a transitional environment on presence was not directly measured.

It was not until 11 years after the Slater et al. (1998) experiment that the question was asked as to whether or not a gradual transition to the virtual world increases presence (Steinicke et al. 2009). In the experiment, participants donned a HMD as well as headphones and experienced a virtual airplane flight; half of the 10 participants started the experience in the plane, while the other half started in a replication of the laboratory. Prior to takeoff, participants in both conditions navigated their respective environments and after 5 min sat down in a physical mockup of the airplane seat. The transitional environment increased feelings of presence and participants moved more safely and naturally through the airplane. Apart from the small sample size, which included two of the authors, the transitional environment was inherently more interactive, in terms of both tactility and verbal communication with experimenters, which could have caused the increased presence ratings as previous research has shown that interactivity increases presence (Welch et al. 1996).

2.1 Purpose and hypothesis

To this point, the goal of the current research was to test whether transitional virtual spaces which replicate a known physical space increase presence. This was done with bare-bones equipment (desktop virtual reality, no audio, and no unessential experimenter interaction) to highlight that even equipment which should produce low levels of immersion can induce higher feelings of presence given the use of a transitional environment, hereinafter referred to as a “preamble.” A preamble is a virtual replica of the immediate physical environment, having the sole purpose of giving a user a more natural transition into VR, rather than immediately throwing them into the infinite possibilities of a VR experience. It was hypothesized that in a low-immersion system, users starting a virtual reality experience in a preamble would report a greater degree of presence in a subsequent novel DVE, than users starting a virtual reality experience in an unfamiliar DVE, who then transition to a novel DVE.

3 Method

3.1 Design

The experiment was conducted in the Psychology East Basement at the University of California, Santa Barbara, during the winter quarter of 2016. The participants completed the entirety of the experiment in front of a 27-inch LED Monitor with a screen refresh rate of 60 Hz. The computer powering the experiment had an i7-47900k CPU clocked at 4.00 GHz and 8 GB of RAM. The graphics card was a NVIDIA GeForce GTX 750 Ti. All navigation in the experiment was done using a computer mouse and the WASD keys on a keyboard, which were colored red for easier reference. Participants had a first person perspective but did not have a virtual body inside the virtual environment, and aside from navigating through the virtual world, they could not interact with it in any other way. During recruitment, the study was presented as “Navigation in Virtual Environments.”

The current study involved one between subjects factor, the starting area; participants entered virtual reality in either a DVE that replicated the laboratory space (preamble) or a novel DVE. Both conditions ended the study by exploring a virtual museum that was connected to the aforementioned starting areas by a set of stairs. All models were constructed using SketchUp Pro (v. 14.1.1282; Trimble Navigation Limited 2014). The virtual worlds were then rendered in Vizard (v. 5.2; WorldViz 2015), with which the system maintained a frame rate of 60 frames per second. See Figs. 1, 2, 3, 4, 5 and 7 for pictures of the laboratory and models, and the Procedure section for how they were incorporated into the experiment.

Fig. 1
figure 1

Laboratory where participants conducted the experiment

Full size image
Fig. 2
figure 2

Virtual starting location in the experimental condition

Full size image
Fig. 3
figure 3

Hallway that participant walked through to enter the real laboratory, and to leave the virtual laboratory

Full size image
Fig. 4
figure 4

Lobby where participant waited for experimenter, as well as final virtual location before entering the virtual museum

Full size image
Fig. 5
figure 5

Starting location in the control condition

Full size image

3.2 Models

The virtual laboratory was created by measuring the real-world dimensions and then translating them to SketchUp. The dimensions were accurate to the order of one inch. Pictures of unique textures were taken on a Samsung Galaxy S4 and then fitted onto the virtual laboratory. Generic textures, such as the color of the walls, were made using SketchUp’s color palette. The fastest way a participant could get to the virtual museum from the starting point was 20 s.

The novel DVE was a virtual house that was downloaded from the SketchUp warehouse and modified to incorporate the virtual museum. In order to reach the virtual museum from the starting point, the fastest route took 18 s, which compared to 20 s is a negligible difference (Seow 2008).

The virtual museum was downloaded from the SketchUp warehouse and then populated with various artwork found on the Internet, as well as with sculptures downloaded from the SketchUp warehouse. In total, there were 56 paintings, 17 sculptures, and 2 large exhibits. The purpose of this proposed target application was to display a virtual environment visitors could investigate as they would a real museum.

3.3 Procedure

Participants entered the laboratory (Fig. 1) and reported their height so as to set the virtual eye height at the same level as their actual eye height. This was done in order to control for the possibility that some participants would be taller or shorter than the default eye height, which would be a potential confound. They then completed a consent form and answered questions about prior experiences on the computer. They were told that their task was to explore a DVE and were randomly assigned to one of the two conditions:

3.3.1 Experimental

The participant began their virtual experience in a DVE which was a recreation of the laboratory (preamble; Fig. 2). Once in the preamble, they were verbally directed to navigate out of the laboratory (Fig. 3) by leaving through the open door and turning right to walk down the hallway. They were then told to turn left at the first door and to go through the lobby (Fig. 4) and up the stairs where they then entered a virtual museum (Fig. 7). Once in the museum, experimenters did not interact with the participant.

3.3.2 Control

The participant found themselves in the bathroom of a novel DVE, a model home (Fig. 5). They were verbally directed to leave through the open door and to take a right at the door leaving the bedroom (Fig. 6). Then, they were told to keep right and navigate through the living room, where they were then told to go through the hallway and up the stairs to the same virtual museum (Fig. 7) as in the experimental condition, where once again, experimenters did not interact with the participant.

Fig. 6
figure 6

Overhead view of the control condition starting location

Full size image
Fig. 7
figure 7

Virtual museum that both conditions explored

Full size image

In both conditions, after exploring the museum for 5 min, the participant exited the DVE. The participant was then asked to answer a questionnaire regarding immersion and presence. Finally, participants were debriefed and thanked for their participation.

3.4 Participants

For the study, 70 participants (41 females; M age = 20.10, SD = 2.43) from the undergraduate subject pool at the University of California Santa Barbara completed the experiment in exchange for a $5 Amazon gift card. The sample was 35.2% Caucasian (n = 25), 5.6% African American (n = 4), 35.2% Asian (n = 25), 14.1% Hispanic (n = 10), and 8.5% Mixed or Other ethnicity (n = 6). Participants were randomly assigned to conditions (21 females and 14 males in experimental condition, 20 females and 15 males in control condition).

3.5 Measures

3.5.1 Experience questions

In order to confirm that there were no significant differences in background that would influence the general DVE experience, participants responded to three questions about weekly game play, prior exposure to the laboratory setting, and wait time before the study began. Specifically, they were asked, “How many total hours per week do you spend playing computer, video, or arcade games? Please do not include non-gaming computer use,” “How many times have you been to the basement?,” and “How many minutes did you wait for the experimenter to greet you?”.

3.5.2 General presence

A modified single-item question was used to measure general presence, “If your level of presence in the real world is 100, and your level of presence is 0 if you have no presence, rate your level of presence in the virtual museum” (Barfield et al. 1995). Participants ranked their general feeling of presence on a scale from 1 to 100 (M = 65.74, SD = 19.87, range 20–100).

3.5.3 Specific presence

A well-known presence questionnaire with seven subscales was modified (Witmer and Singer 1998). We presented questions from five of the subscales: realism, possibility to act, quality of interface, possibility to examine, and self-evaluation of performance. Participants responded to the 15 questions on a scale from 1 (Not at all) to 7 (Completely). In addition, a widely used reality judgment and presence questionnaire with three subscales was modified for the current research (Baños et al. 2000). Two of the subscales were selected as they had the closest link to our DVE experience: reality judgment, and attention/absorption. Participants responded to eight statements on a scale from 1 (strongly disagree) to 7 (strongly agree). See Table 1 for descriptive statistics.

Table 1 Summary of means, standard deviations, and correlations for scores on presence and immersion questions
Full size table

3.5.4 Realism

Participants responded to six questions about realism (e.g., “How much did your experiences in the DVE seem consistent with your real-world experiences?”). The six questions showed high internal reliability (α = .77); the six items were averaged together for use in later analyses (M = 4.92, SD = 0.91).

3.5.5 Possibility to act

Participants responded to two questions about their possibility to act (e.g., “How responsive was the environment to actions that you initiated (or performed)?”). The two questions showed moderate correlation [r(70) = .34, p < .01]; the two items were averaged together for use in later analyses (M = 5.14, SD = 1.24).

3.5.6 Quality of interface

Participants responded to three questions about the quality of interface (e.g., “How much delay did you experience between your actions and expected outcomes?”). The three questions had a close to acceptable reliability (α = .64); the three items were averaged together for use in later analyses (M = 5.13, SD = 1.19).

3.5.7 Possibility to examine

Participants responded to two questions about their possibility to examine (e.g., “How well could you examine objects from multiple viewpoints?). The two questions showed moderate correlation [r(70) = .38, p < .001]; the two items were averaged together for use in later analyses (M = 5.78, SD = 0.90).

3.5.8 Self-evaluation of performance

Participants responded to two questions about their self-evaluation of performance (e.g., “How quickly did you adjust to the DVE experience?”). The two questions showed strong correlation [r(70) = .44, p < .001]; the two items were averaged together for use in later analyses (M = 5.77, SD = 0.89).

3.5.9 Reality judgement

Participants responded to five statements about reality judgment (e.g., “I felt like I ‘went into’ the virtual world”). The five questions showed high internal reliability (α = .81); the five items were averaged together for use in later analyses (M = 4.41, SD = 1.19).

3.5.10 Attention/absorption

Participants responded to three statements about attention/absorption (e.g., “I forgot I was in a room looking at a monitor”). The three statements showed high internal reliability (α = .80); the three items were averaged together for use in later analyses (M = 3.90, SD = 1.49).

4 Results

We hypothesized that starting a virtual experience in a recreation of a user’s immediate physical environment (a preamble) would induce a greater experience of presence in the virtual world, relative to starting a virtual experience in a novel environment. In addition, after analyzing the results, we found that women tended to experience presence to a slightly greater extent than men, although results were not significant, but merely suggestive. To begin, the sample was screened for missing values and normality, and descriptive statistics and correlations were calculated (see Table 1 for correlations and descriptive statistics key variables).

Next, differences in general experience prior to the study by both condition and gender were assessed (see Table 2 for means by condition). No differences by condition were found for the amount of time spent waiting before being greeted by the experimenter [t(61.85) = 1.16, p = .25], nor the number of times the participant had previously been to the laboratory [t(40.37) = 1.39, p = .17], nor the total hours spent playing video games [t(68) = −0.23, p = .82]. Similarly, no differences by gender were found for the amount of time spent waiting before being greeted by the experimenter [t(68) = −0.04, p = .97]. However, significant differences by gender in the number of times the participant had previously been to the laboratory were found [t(44.68) = −2.02, p < .05], such that women (M = 2.71, SD = 5.58) reported having been to the laboratory more times in the past than men (M = 0.90, SD = 1.15). Additionally, a significant difference by gender was observed for total weekly hours of video game play [t(30.30) = 3.89, p < .001], where men, on average, spent more time playing video games (M = 4.66, SD = 5.49) than women (M = 0.61, SD = 1.32), which coincides with previous findings regarding gender differences in time spent playing video games in college (Ogletree and Drake 2007).

Table 2 Summary of means and standard deviations for scores on presence and immersion questions by condition
Full size table

4.1 Presence

Independent samples t tests were conducted to evaluate the hypotheses that participants in the experimental condition would experience greater levels of presence than participants in the control condition and that women would experience greater levels of presence than men. Presence was measured with a single general presence item as well as with seven subscales of a specific presence measure (realism, possibility to act, quality of interface, possibility to examine, self-evaluation of performance, reality judgement and attention/absorption).

Condition. Participants in the experimental condition reported more general presence (M = 70.54, SD = 14.24) than participants in the control condition [M = 60.94, SD = 23.47; t(56.04) = 2.07, p < .05]. No significant differences by condition were reported for realism [t(61.65) = 1.41, p = .16], possibility to examine [t(68) = .066, p = .95], quality of interface [t(68) = 0.27, p = .79], self-evaluation of performance [t(68) = 0.94, p = .35], nor attention/absorption [t(68) = 0.91, p = .37]. However, there was a significant difference by condition for possibility to act [t(63.24) = 2.07, p < .05] and in reality judgment [t(68) = 2.40, p < .05]. Participants in the experimental condition felt that they had more possibilities to act (M = 5.44, SD = 1.03) than participants in the control condition (M = 4.84, SD = 1.37). In addition, participants in the experimental condition (M = 4.74, SD = 1.01) judged the experience as more realistic than those in the control condition (M = 4.08, SD = 1.27).

Gender. A marginally significant difference by gender in general presence was observed [t(68) = −1.75, p = .08], with women experiencing more presence (M = 69.2, SD = 18.32) than men (M = 60.86, SD = 21.25). No significant differences by gender were observed for realism [t(68) = −1.711, p = .22], quality of interface [t(68) = −0.38, p = .71], possibility to examine [t(68) = −0.83, p = .41], self-evaluation of performance [t(68) = .58, p = .56], reality judgment [t(60.70) = −1.03, p = .31], nor attention/absorption [t(68) = −0.96, p = .34]. However, a marginally significant difference by gender in possibility to act was observed [t(68) = −1.71, p = .09], with women reporting more possibility to act (M = 5.35, SD = 1.15) than men (M = 4.84, SD = 1.32).

5 Discussion

It was hypothesized that under a low-immersion system, users starting a virtual reality experience in a preamble would report a greater degree of presence in a subsequent novel DVE. Our findings show that participants in the experimental condition (laboratory recreation preamble) reported higher scores for reality judgment, felt that they had more possibilities to act in the DVE, and felt more present overall.

The finding that participants in the preamble reported higher scores for reality judgment, but that both conditions scored the same in realism is admittedly curious. Importantly, the results for realism come from the Witmer and Singer questionnaire (1998), which is concerned with presence, while scores for reality judgement from Baños et al. (2000), which is concerned with VR experiences in the scope of mental health. Realism is concerned with why people believe what is shown to them, and it deals with factors regarding scene realism, consistency of information with the physical world, meaningfulness of experience, and disorientation upon returning to physical reality (Witmer and Singer 1998). On the other hand, reality judgment is concerned with the “willing suspension of disbelief” and the treatment of experiences in VR as coinciding with reality (Baños et al. 2000). Having high levels of realism does not imply that participants will judge the experience as having reality. This is most obvious in the case of gaming, where the images on the screen seem realistic, but are nonetheless judged as being unreal.

In sum, participants in both conditions judged the DVEs as being equally realistic, yet those in the preamble condition felt their virtual experience as being more veritable. A possible reason for this is that the realism questions were concerned with solely the virtual environment, while the reality judgment questions compared the virtual environment to the physical one. It intuitively makes sense that the preamble condition scored higher. Too often, reality judgment is either subsumed into the concept of presence or ignored (Baños et al. 2000). Reality judgment is relevant to both treating phobias (Quero et al. 2008) and the efficacy of mass media (Shapiro and McDonald 1992); hence, further research is needed to tease apart the significance of reality judgment in VR.

The finding that those participants that started in the preamble felt that they could do more things in the DVE relative to the control group is peculiar, but perhaps closely linked to the findings of Steinicke et al. (2009). In their study, participants moved more safely and naturally in the airplane model when they started in a preamble, and later in a subsequent study, they found that a preamble bestowed a better ability to estimate distances in a novel DVE (Steinicke et al. 2010); it remains unclear whether the distance estimation comes from the increased presence, or from higher-level cognitive processes that are affected by starting in a preamble. It may be that the comfort that a preamble provides, in both familiarity and improved distance estimation gave participants the belief that they could do more in the DVE.

Perhaps the reason as to why participants in the preamble condition experienced a greater sense of presence and reality judgment comes from the fact that they started their virtual experience in a familiar environment. Drawing on foundational psychological theories, repeated exposures of familiar stimuli leads to greater preference for the stimuli (mere exposure effect; Zajonc 1968). Hence, it is of little surprise that familiarity (such as the familiarity of the recreated laboratory DVE) provides benefits across many various phenomena; when given a practice problem to work on, and then given a familiar or a novel problem, participants found the familiar problem to be of higher quality (Soppe et al. 2005). In studies on memory, familiarity was found to be important in forms of learning that are not dependent on meaning (Epstein et al. 1960). Even guppies learn better from familiar guppies than unfamiliar ones (Swaney et al. 2001), which suggests that to a certain extent, preference for familiarity is hard-coded in organisms.

There is something about familiarity that attracts people. Given that part of self-identity has to do with the continuity of memory (Kihlstrom et al. 2003), then perhaps starting a virtual experience in a preamble increases presence because it is a continuation of a memory of place. By starting in a preamble, a user may feel less disconnect between their grounded reality and their virtual one. With less disconnect, it could be easier for a user to identify with their experience in the DVE, which enhances the experience of presence.

Finally, the discrepancy in experiencing presence between the two genders could be due to the following factors. Due to the nature of the virtual experience being more observational than interactive, the finding that women tended to experience slightly more presence than men can be explained by previously documented differences in experience of presence between the two genders, where women appear to engage in presence by watching the environment, while men by interacting with it (Nicovich et al. 2005), as well as that men tend to respond less to visual complexity than women (Lombard et al. 2000). Additionally, since the number of times having been to the basement was greater for women than for men, the greater familiarity with the environment could have increased presence. However, based on our preliminary and marginally significant results, conclusions drawn from our findings should be made tentatively and followed up with more empirical research.

Given the inherent problems in using presence questionnaires across different immersive mediums (Usoh et al. 2000), these results cannot be extrapolated onto other mediums, but since similar findings have been reported on immersive technology (Steinicke et al. 2010), it can be safely assumed that preambles should increase presence in both desktop and HMD applications. However, the experimental condition was more detailed than the control condition due to the necessity of having a faithful replication; thus, the difference in detail could be a possible confound. The gender differences, although suggestive, are only marginally significant, so a larger sample in a future study would allow researchers to better understand the differences in presence by gender.

Additionally, future experiments could address the issue of how to incorporate a preamble when users are in differing physical locations by employing the “stacking depth” technique, a technique where users simulate entering a DVE while already in a DVE (Slater et al. 1994). The experiment could involve having users start their virtual experience in a novel DVE, and then by employing the stacking depth technique, they find themselves in the same DVE, which then functions as a preamble.

6 Conclusions

Since increasing presence is desired among both users and developers of DVEs, it is recommended in future studies to make the starting point in DVEs a replication of the immediate physical environment. However, implementing a preamble should be done with care and in such a way that it relates to the virtual experience as a whole. For example, if making a fantasy DVE, the transition from preamble to desired DVE has to be fluid and believable, rather than abrupt and disconnected. Preamble environments should not be used when utilizing the “impossible spaces” technique, which utilizes self-overlapping architectural layouts allowing the designer to fit a large virtual area in a significantly smaller room (Suma et al. 2012). This is because the technique is sensitive to distance estimation, and the increased distance estimation from a preamble could make it easier to shatter the illusion. Importantly, incorporating this method of starting a DVE in a replica of the physical environment will allow designers of VEs to augment their existing immersive technology to increase presence, without having to invest in more expensive hardware.

In regard to implementing a preamble, a good method is to follow the five-stage transition process. In this process, a user is habituated to the VR equipment in a preamble and then personally initiates the transition, which is followed by a physical transition with the proper biomechanical feedback, such as pressing a button to open a portal or to lower/raise a stage. Next, the user goes through a limbo period which is dependent on the means of transition, such that a portal transition should have appropriate visual and auditory stimuli, while a transition via lowering/raising a stage should provide appropriate haptic feedback. In general, the limbo period is marked by the process of translation and should accompany the physical translation with a mental one. Finally, the last stage is the entrance into the desired virtual environment, one that is not wholly disassociated from the preamble, but one that lets the user know that they are now in a whole new DVE (Sproll et al. 2013).

In conclusion, the content of a DVE is deeply important to users’ experiences of virtual reality and their sense of presence in the digital virtual world. Although improving the technology that makes virtual reality possible is necessary, finding new and unique ways to pull users into the experience is important, especially when the technology is limited. The efficacy of preambles may be because they offer a gradual transition into the virtual world, such that the familiarity eases users into the novel experience.