CPSC-4110 Exam 1: User Experience

Presence

The psychological feeling of being “there” in a virtual environment.

Immersion

The extent to which a system provides sensory information that surrounds the user.

Presence vs. Immersion

Immersion is a system property; presence is the user's psychological experience.

Place Illusion

The feeling that you are physically located in the virtual environment.

Plausibility Illusion

The feeling that events occurring in the virtual environment are actually happening.

Self-Presence

The feeling that your virtual representation is your own body.

Attention

The process of selectively focusing on particular information or stimuli.

Top-Down Perception

The brain uses expectations, prior knowledge, and context to interpret sensory information.

Intention-Action Model

Presence is supported when intended actions produce expected virtual results.

Embodiment

The feeling that a virtual body is your own body.

Self-Location

The feeling that you are located within or at your virtual body.

Agency

The feeling that you control your virtual body's movements.

Body Ownership

The feeling that a virtual body belongs to you.

Embodiment Components

Self-location, agency, and body ownership.

Avatar

A virtual representation of the user in a virtual environment.

Avatar Control

How accurately and responsively the virtual body follows the user's movements.

Avatar Appearance

The visual characteristics of a user's virtual body.

Avatar Design Priority

Control and accurate tracking should generally be prioritized over appearance.

Proteus Effect

The tendency for a person's behavior to change based on their virtual avatar.

Midas Touch Problem

Unintentional movements are interpreted as deliberate inputs.

Clutch

A deliberate action that separates intentional input from normal movement.

Hand Tracking

Using cameras or sensors to detect and reproduce the user's hand movements.

Controller

An input device providing buttons, sticks, triggers, and often haptic feedback.

Hand Tracking Advantage

Hands can be represented naturally without holding a physical controller.

Hand Tracking Disadvantage

Tracking can fail and there is little physical feedback from buttons.

Tracking Failure

When the system loses accurate information about a user's body or hands.

Occlusion

When one object or body part blocks another from the tracking system.

Three-Point Tracking

Tracking the head and both hands while estimating other body parts.

Inverse Kinematics (IK)

Estimating body joint positions from known positions of other body parts.

Proprioception

The sense of where your body and limbs are positioned without looking.

Locomotion

Movement of the user through a virtual environment.

Artificial Locomotion

Virtual movement produced by an input rather than physical walking.

Partial Gait

Locomotion that reproduces only part of natural walking.

Gait Negation

Physical walking-like movement occurs while technology prevents actual displacement.

Real Walking

The user physically walks through the virtual environment.

Teleportation

Instantly moving the user to a selected location in the virtual environment.

Teleportation Advantage

It generally reduces cybersickness and works well in limited physical spaces.

Teleportation Disadvantage

It can reduce continuous movement cues and spatial updating.

Continuous Locomotion

Continuous virtual movement controlled by an input such as a joystick.

Continuous Locomotion Advantage

It provides continuous and precise virtual movement.

Continuous Locomotion Disadvantage

It can increase the risk of cybersickness.

Room-Scale VR

VR in which the user physically moves around a tracked real-world space.

Locomotion Selection

Choose locomotion based on application goals, users, space, comfort, and presence.

Cybersickness

A form of motion sickness associated with virtual reality experiences.

Sensory Conflict

Cybersickness can occur when sensory systems provide conflicting information about movement.

Visual-Vestibular Conflict

Visual motion indicates movement while the vestibular system indicates little or no movement.

Vestibular System

The sensory system that detects head movement, acceleration, and balance.

Semicircular Canals

Inner-ear organs that detect angular acceleration and rotational movement.

Otolith Organs

Inner-ear organs that detect linear acceleration and gravity.

Snap Turning

Instantly rotating the virtual viewpoint to reduce continuous visual rotation.

Vignette

A visual technique that reduces peripheral vision during movement to help reduce cybersickness.

Stable Visual Reference

A stationary visual element that can help reduce sensory conflict during movement.

Sensory Conflict Reduction

Reducing disagreement between visual, vestibular, and physical movement cues.

Interaction Affordance

A feature that communicates or enables what actions a user can perform.

Manipulation

Interacting with virtual objects by actions such as grabbing, rotating, moving, or throwing.

Navigation

Moving through a virtual environment.

System Control

Interacting with the system through functions such as menus, settings, and tools.

Signifier

A cue that communicates how or where an interaction can be performed.

False Affordance

An interface feature that appears interactive but does not support the expected action.

Effectiveness

How successfully an interaction accomplishes the user's goal.

Ease of Learning

How quickly a new user can understand and learn an interaction.

Ease of Use

How easily an interaction can be performed after it has been learned.

Comfort

How physically and cognitively comfortable an interaction is over time.

Interaction Realism

How closely an interaction resembles its real-world counterpart.

Realism vs. Usability

A realistic interaction is not always the most effective or usable interaction.

Feedback

Information provided to the user about the state or result of an interaction.

Hover Feedback

Feedback indicating that an object is available or being targeted.

Selection Feedback

Feedback indicating that an object or option has been selected.

Result Feedback

Feedback indicating that an action produced an effect.

Visual Feedback

Information communicated through changes in appearance or visuals.

Audio Feedback

Information communicated through sounds.

Haptic Feedback

Information communicated through physical sensations or vibrations.

Basin of Attraction

A larger target region that allows an object to snap into a desired position.

Snapping

Automatically aligning an object with a nearby intended position.

Degrees of Freedom (DOF)

The independent dimensions in which an object or body can move.

6 Degrees of Freedom

Three positional axes plus three rotational axes.

Position

X, Y, and Z movement through space.

Rotation

Pitch, yaw, and roll movement around axes.

Remapping

Mapping physical movements or inputs to a different virtual movement or action.

World-Space UI

A user interface positioned within the virtual environment.

Head-Locked UI

A UI element that remains attached to the user's viewpoint.

Hand-Anchored UI

A UI element positioned relative to the user's hand.

Object-Anchored UI

A UI element positioned relative to a specific virtual object.

UI Accessibility

Designing interfaces so users with different abilities can effectively interact with them.

Cognitive Map

A mental representation of spatial relationships within an environment.

Landmark Knowledge

Knowing the locations of important objects or landmarks.

Route Knowledge

Knowing how to travel between locations.

Survey Knowledge

Understanding the overall spatial layout and relationships between locations.

Spatial Updating

Updating your understanding of your location as you move through an environment.

Internal Spatial Cues

Spatial information from proprioception and the vestibular system.

External Spatial Cues

Spatial information from visual landmarks, optical flow, and environmental cues.

Real Walking and Spatial Updating

Real walking provides strong physical and sensory cues for updating spatial position.

Teleportation and Spatial Updating

Teleportation provides fewer continuous movement cues for updating spatial position.

Agency and Locomotion

Natural correspondence between physical and virtual movement can increase agency.

Locomotion and Embodiment

Movement that matches the user's physical actions can strengthen embodiment.

Locomotion and Presence

Consistent, responsive movement can strengthen the feeling of being present.

Locomotion and Cybersickness

Visual and physical movement mismatches can increase cybersickness.

Locomotion and Spatial Knowledge

Continuous physical movement generally provides stronger spatial updating than teleportation.

User Population

An important factor when selecting a locomotion or interaction technique.

Application Goals

What the user needs to accomplish should guide interaction and locomotion design.