Can the experience of space be differentiated in a similar way to the experience of time, where we can distinguish between the experience of the duration of time and the experience of the passing of time?

The question probes whether the experience of space can be differentiated analogously to the classic distinction in the experience of time—namely, between duration and passage. That is, while in time we distinguish between perceiving intervals (duration) and sensing the flow or passage, can we find similar dual aspects structuring spatial experience?

Analogy with Temporal Experience

In the philosophy and psychology of time, two principal aspects of temporal experience have long been recognized:

• Duration: The capacity to perceive temporal intervals—how long events or periods last.
• Passage: The phenomenological sensation of time “passing,” giving a sense of dynamic change from past to future.

Empirical research supports the psychological and neural distinctness of these aspects. Duration is processed through specific perceptual channels and mechanisms[1], influenced by attention and context[2]. The feeling of passage—the sense that now “moves”—is more elusive and deeply phenomenological.

Structure of Spatial Experience

Phenomenological and empirical investigations reveal an analogous, though not identical, structure for spatial experience:

1. Experience of Extension or Distance

This refers to our perception of measurable spatial attributes: how far apart objects are, their size, orientation, and our ability to judge distance and layout. This dimension is studied extensively in psychology and neuroscience[3][4]. For example, visual space perception research distinguishes between object location (where is it?) and metric properties (how far away is it? how large is it?)[3]. These properties are processed by dedicated neural mechanisms, much as duration channels mediate time perception[1].

2. Experience of Spatial Presence or Situatedness

In parallel with the experiential passage of time, there is a phenomenology of being here—the embodied, lived experience of inhabiting space. This is not just knowing distances or layouts, but the “hereness” or “thereness” that underpins our movement and interaction in the world[3][4]. Phenomenological approaches, notably by Merleau-Ponty, emphasize the centrality of the body: space is not a neutral container, but an orientational field we are always already immersed in[3]. Neuroscience corroborates this distinction through egocentric (body-centered) versus allocentric (environment-centered) spatial coding[3].

Theoretical Support and Limits

The analogy holds in that both time and space are experienced through quantifiable dimensions (duration and extension/distance, respectively) and through a more subjective, immersive structure (passage and situatedness). However, the analogy is not perfect, and research has highlighted meaningful differences:

• Distinct Representational Modalities: Unlike time, whose structure may be more amodal and uniform, space is processed differently depending on sensory modality and context, potentially limiting a direct analogy with time[5].
• Neural Mechanistic Overlap: Recent studies indicate shared computational principles for coding time and space, suggesting that the brain may apply analogous mechanisms for the perception of temporal and spatial extent[1][6].
• Cultural and Conceptual Distinctions: Cultures vary significantly in their conceptualization and linguistic framing of spatial and temporal relations, which can further complicate strict analogies[7][8].

Empirical Correlates

Research in cognitive neuroscience demonstrates that the perception of both time and space engages similar processing mechanisms, particularly in the representation of extent (duration for time, distance for space)[1][6]. Specifically, “duration channels” for time perception function similarly to the channels for processing spatial attributes such as size or distance. Moreover, tasks that require comparative judgment in time (e.g., which interval is longer) parallel those in space (e.g., which line is longer), and both may be influenced by attentional and contextual factors[1][2][3]. However, as Buzsáki & Llinás note, brains may not represent time or space directly but instead process event successions that we later interpret as spatial or temporal structures[9].

Conclusion

Yes, the experience of space can be differentiated in a way akin to time, distinguishing (1) an experience of extension (distance, size, orientation) and (2) an experience of spatial presence or immersion, which is analogous in some respects to the passage of time. Such distinctions are supported by both philosophical analysis and empirical research in cognitive neuroscience and psychology. Nonetheless, the analogy is not exact and is qualified by differences in phenomenological structure, neural representation, and cultural framing[7][5][8][3][4]. Overall, the parallel structure enriches our understanding of how humans cognitively and phenomenologically engage with the dimensions of their environment, suggesting that both temporal and spatial experience are fundamentally dual in nature, comprising quantifiable extents and immersive, orientational presence[3][4].

To differentiate between duration of time and passage of time, as well as extension of space and spatial presence or situatedness, participant instructions must be precisely tailored to probe distinct aspects of temporal and spatial experience. Drawing on the theoretical and empirical literature, here is a robust protocol, with instructions matched to current research and adjusted to avoid conceptual ambiguity.

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1. Differentiating Duration of Time vs. Passage of Time

A. Duration of Time

Intent: Isolate participants’ perception of temporal extent, as measured in seconds or as a comparative magnitude between intervals. This is foundational in both basic and applied studies of time perception, and is best elicited by focusing attention on “how long” an event lasted, minimizing subjective flow or emotional content[1][2][3].Instructions:

“In each trial, focus on how long the event or interval lasts. Do not concern yourself with whether time felt fast or slow. Your task is to judge, as precisely as you can, the amount of time that has passed—think of it as if you were using a timer. After each trial, estimate the duration in seconds, or indicate which of two intervals was longer.”[1][4][3]

Follow-up Questions:

• “How long did this interval feel, in seconds?”
• “Was this event longer or shorter than previous ones?”
• “How confident are you in your estimate?”

These align with established experimental paradigms for duration perception (e.g., temporal bisection tasks, interval reproduction), and map onto duration-selective channels in early sensory processing[1].

B. Passage (or Flow) of Time

Intent: Capture the phenomenological, qualitative sense of time “moving,” “flowing,” or “passing,” distinguished from measured duration[4][5]. This is essential in studies probing subjective time under varying attentional or affective states.Instructions:

“During each trial, attend to your experience of time itself. Rather than judging the length of the interval, focus on whether time feels like it is ‘passing’ quickly, slowly, or not at all. Pay attention to your sense of the present moment moving forward. Afterward, describe how time felt during the interval.”[4][5]

Follow-up Questions:

• “Did time feel as if it was moving quickly, slowly, or standing still?”
• “Did you notice any change in your sense of time’s flow during the activity?”
• “How did your attention or mood affect your perception of the passage of time?”

This approach draws on phenomenological and introspective methods, often used in studies on temporal experience under absorption, boredom, or altered states[4][5].

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2. Differentiating Extension of Space vs. Spatial Presence/Situatedness

C. Extension of Space

Intent: Probe participants’ perception of spatial metrics such as distance, size, or object relations—concepts central to classical and ecological theories of spatial perception[6][7]. Instructions must direct attention to “how far,” “how big,” or “how close,” independent of embodiment or first-person location.Instructions:

“As you observe the display (or environment), focus on the measurable aspects of space: distances between objects, their sizes, and how they are arranged. Imagine you are measuring these distances—report how far apart objects are, or how large or small they appear compared to each other or to known reference points.”[6][7]

Follow-up Questions:

• “How far apart did the objects appear?”
• “What was your judgment about the size or layout of the objects?”
• “Did any spatial dimension (length, width, height) seem larger or smaller than expected?”

This aligns with methods from visual psychophysics—such as judgments of length, distance, or layout[6][7].

D. Spatial Presence or Situatedness

Intent: Shift focus from spatial extension to the first-person, immersive sense of being located within a space—the “hereness” or “thereness” of embodied spatial experience, as stressed in ecological and phenomenological accounts[7]. This domain is best accessed through introspective and embodied awareness tasks, such as VR immersion or guided reflection[6][7].Instructions:

“During the experience, focus on your sense of being located somewhere within the environment. Pay attention to what it feels like to ‘be here’—your sense of your own position and presence in space, rather than distances or measurements. Reflect on whether the environment feels like something you are in, or something you are observing from outside.”[7][6]

Follow-up Questions:

• “Did you feel present or located in a specific place? Where?”
• “How aware were you of your own position or presence in the space?”
• “Did you experience the environment as enveloping you, or as something remote or external?”

This approach addresses the deeper phenomenology of spatial presence, related to the ecological interface between agent and environment[7].

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3. Reference Table

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Additional Recommendations and Rationale

• Pilot these instructions to ensure that participants reliably distinguish between the targeted experiential dimensions[5].
• Use both quantitative measures (e.g., rating scales for speed of passage or strength of presence) and qualitative interviews to triangulate data[5].
• Be aware of potential conflation between duration and passage (or extension and presence), especially in cultures or contexts where these distinctions are not routinely articulated—see cross-cultural findings[8][9].

These protocols draw explicitly on empirical models for temporal and spatial perception that distinguish between “extent” (duration, extension) and “presence” (flow, situatedness), aligning with findings that spatial and temporal information can be processed both through shared and distinct mechanisms[1][4][6][7][5][2][3].

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This differentiated instruction structure offers a robust experimental and phenomenological framework for disentangling duration vs. passage in time, and extension vs. presence in space, grounded in contemporary research.

Spatial presence—the subjective experience of “being there” in a spatial environment—has become a central focus in research leveraging virtual reality, media environments, and interactive systems. Unlike objective spatial measures (such as extension or distance), spatial presence concerns a cognitive feeling or sense of embodiment and immersion within an environment, often independent of actual physical location[1].

To measure spatial presence robustly, researchers employ a multi-method approach: validated self-report questionnaires, behavioral indices, physiological or neural measures, and qualitative/phenomenological methods, each aligning with theoretical models of the formation of spatial presence[2].

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1. Self-Report Questionnaires

Standardized questionnaires remain the most direct and widely validated method for capturing spatial presence as a subjective phenomenon. These instruments operationalize spatial presence through items assessing the degree to which users feel located “inside” a mediated environment and can act within it, rather than merely observing it externally.

Key Scales:

• Presence Questionnaire (PQ): Focuses on the sense of being in the environment, naturalness of interaction, and sensory engagement[3]. Sample item: “To what extent did you feel you were inside the environment?”
• Igroup Presence Questionnaire (IPQ): Dissects spatial presence into self-location, involvement, and experienced realism, directly tapping the “being spatially located” dimension[1]. Sample item: “It felt as though I was physically present in the environment.”
• MEC Spatial Presence Questionnaire (SPQ): Grounded in process models, this instrument relates presence to psychological “spatial situation models” and determinants such as attention allocation and involvement[2].
• Pictorial Presence Self-Assessment Manikin (SAM): This recently developed, validated pictorial format accelerates and simplifies the assessment of spatial presence, enabling intuitive and reliable measurement across diverse populations and conditions[4]. The scale captures both self-location and possible actions within the environment.

Validation work has shown high sensitivity of these instruments to design manipulations (e.g., levels of distraction, media type) and strong convergent validity among sub-dimensions of spatial presence[4].

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2. Behavioral Measures

Behavioral indices provide implicit evidence of spatial presence, often confirming or supplementing questionnaire data[2]:

• Naturalistic exploration: Users with higher spatial presence move, orient, or interact in virtual spaces as if those were physical. For instance, they may avoid bumping into virtual objects or “walk” around obstacles.
• Task-based performance: Accurate spatial navigation or memory for virtual layouts can suggest that users feel present, as their actions reflect a “being there” mode of cognitive mapping.

Such behaviors are taken as indirect proxies but must be interpreted alongside self-report, given the possible dissociation between action and subjective experience[2][5].

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3. Physiological and Neurological Measures

Physiological responses (e.g., heart rate, skin conductance) and neuroimaging findings (e.g., fMRI activation patterns) can index engagement with spatial environments, providing further evidence for presence—even when self-report may be unreliable or subject to demand characteristics[2]:

• Increased physiological arousal in response to environmental events (such as threats) often accompanies heightened spatial presence.
• Activity in spatial processing regions of the brain (e.g., posterior parietal cortex) is enhanced when users report strong presence.

These measures, while less direct, offer converging validity and help link phenomenological reports to underlying neural mechanisms.

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4. Qualitative and Phenomenological Approaches

Open-ended interviews, think-aloud protocols, and diaries enable researchers to capture the lived experience and subtle gradations of feeling present in space—particularly critical when extending presence measurement beyond digital contexts or when quantitative tools might obscure nuance[2][4]. Participants may be asked, “Did you feel located inside the environment?” or “Describe how it felt to be in that space.”

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5. Theoretical Considerations and Construct Validity

Recent theoretical models conceptualize spatial presence as a cognitive feeling—a conscious feedback loop indicating to oneself that one is located and able to act within a perceived environment[1]. The formation of spatial presence involves attentional focus on the mediated environment, the construction of a spatial situation model, and the suspension of disbelief, all elements now explicitly operationalized in advanced measures like the Pictorial Presence SAM and the MEC Spatial Presence Questionnaire[2][4]. By distinguishing between unconscious spatial-cognitive processing and the feeling of being present, current theories legitimize subjective self-report as a theoretically grounded method for presence assessment[1].

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Summary Table

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In conclusion, spatial presence can and should be measured using a multimodal approach. Validated self-report instruments such as the PQ, IPQ, and pictorial scales like the SAM offer direct and reliable assessment; behavioral and physiological measures provide converging evidence; and qualitative approaches capture rich phenomenological texture[2][1][4][3]. The optimal strategy integrates these, tailored to the research context, to yield a nuanced and theoretically grounded account of spatial presence.

To robustly measure spatial presence in an experiment where participants experience flying through a visible tunnel of varying extensions (length/width) and at different traversal speeds, it is essential to deploy a measurement framework that distinguishes the subjective feeling of being located within the tunnel from general perceptual processing or task performance. Below, I outline evidence-based recommendations anchored in the development and theoretical advancements in spatial presence research.

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1. Theoretical Grounding: What is Spatial Presence?

Spatial presence, according to the most contemporary and theoretically coherent models, is the cognitive feeling that arises when unconscious spatial-cognitive processes present feedback to conscious experience, resulting in the sense of being “there” within a mediated space rather than merely observing it[1][2]. This feeling is distinct from spatial perception (such as distance or extension estimation) or immersion, underscoring the necessity for measurement tools that align closely with this cognitive feedback loop[1][2][3].

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2. Self-Report Measurement: Direct Assessment of Spatial Presence

Self-report questionnaires are the gold standard for capturing the subjective and phenomenological quality of presence, a practice well-justified by both theory and empirical validation[1][4][2][5][3][6]. They are particularly well-suited for experimental comparisons (e.g., tunnel extension, speed) within a single type of mediated environment.

A. Main Instruments

• Presence Questionnaire (PQ): Widely validated for virtual environments, the PQ directly measures the user’s subjective sense of presence[4][5]. Key subscales include Involvement, Sensory Fidelity, and notably, Adaptation/Immersion—relevant for assessing how users adapt to the felt location within varying tunnel contexts.

• Spatial Presence Experience Scale (SPES): Specifically constructed to tap the sense of being spatially located (“self-location”) in a mediated environment[6]. Items focus directly on the psychological state of feeling surrounded by the environment.

• Pictorial Presence Self-Assessment Manikin (SAM): This nonverbal, intuitive instrument measures self-location and agency/action possibilities, and has been shown to be sensitive and efficient in assessing spatial presence, even when language could introduce ambiguity or fatigue[3].

B. Implementation in the Tunnel Paradigm

After each traversal condition (combination of tunnel extension and speed), instruct participants using language that cues their experience of “being there,” e.g.:

“Please indicate how strongly you felt as though you were truly inside the tunnel during the journey, rather than just observing it on a screen.” (Use a 7-point scale: 1 = not at all, 7 = completely.)

Supplement this with several items from validated scales, such as:

• “It seemed to me that I was really flying through the tunnel.”
• “I felt present in the tunnel environment.”
• “I felt like I could reach out and touch the tunnel walls.”

Utilize the PQ, SPES, or pictorial SAM for repeated, fast administration across conditions[4][3][6].

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3. Behavioral and Cognitive Measures: Indirect Indices of Presence

While self-report captures subjective presence, behavioral measures can provide convergent evidence for spatial engagement, as theorized by Wirth et al.'s process model in which spatial situation models facilitate presence[2].

A. Distance and Direction Estimation

After each tunnel traversal, ask participants to estimate:

• How far they traveled (match to actual tunnel length to assess veridicality).
• The direction or location of their starting point (utilizing a joystick or touchscreen).

Enhanced accuracy or confidence in these tasks may correlate with elevated presence, though these are indirect proxies, as they measure embodied action potential and spatial updating[7][2].

B. Navigation Memory or Tunnel Reproduction

Request that participants “draw” or recreate the tunnel’s path or dimensions, as richer, presence-linked “spatial situation models” should improve performance[2].

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4. Brief Manipulation Checks and Control Measures

To confirm that participants are attending to the manipulations (tunnel length, speed), include manipulation check items post-trial:

• “Was the tunnel long or short?”
• “Did you feel you were traveling quickly or slowly?”

This ensures that self-reported presence is being assessed against perceived, not merely programmed, differences in stimulus parameters[2].

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5. Potential for Complementary Physiological or Affective Measures

While self-report remains primary, greater presence often—though not always—tracks with emotional or physiological arousal[8][9]. Heart rate variability or skin conductance responses during traversal (especially in high-speed or narrow tunnels) could provide secondary indices, but must be interpreted cautiously due to possible confounds with anxiety or cybersickness[8][9]. This is particularly relevant if variations in speed and extension increase or decrease user engagement or tension.

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6. Experimental Design and Data Analysis

Adopt a within-subjects factorial design, with each participant experiencing all combinations of tunnel extension and speed, counterbalancing order to control for fatigue or adaptation[2]. Analyze whether subjective presence scores differ across these conditions using repeated-measures ANOVA or mixed-effects models, and where relevant, test correlations between self-report presence scores and behavioral performance or physiological indices.

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Summary Table: Measurement Strategy

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In summary, measuring spatial presence in a tunnel-flight paradigm with variations in extension and speed is most decisively achieved through theoretically grounded self-report questionnaires (PQ, SPES, Pictorial SAM), tailored item wording to your spatial context, and supported by behavioral tasks that probe spatial updating and memory. Manipulation checks ensure experimental validity, and physiological measures offer convergent but secondary insight. This multi-method approach is both justified by—and advances—the current science of spatial presence measurement[1][4][2][5][3][6][7][8][9].