Hello. My name is Rufat Rzayev. Today, I would like to present the work titled
Reading in VR: The Effect of Text Presentation Type and Location.
Virtual reality allows novel approaches for users to view, read, and interact with a text.
In VR, text presentation type and location can be altered to meet users' need.
For example, for better viewability, a text might tilt towards a VR user
if the user is not standing in front of it. Or a user might take an afar text and explore
the virtual environment while reading the text in the field of view. If the available space is small
or a user needs to interact with the text and the virtual environment simultaneously, text in VR can
change its presentation form to display the same amount of text in different display sizes.
For this purpose, presenting text using rapid serial visual presentation (RSVP)
is a promising approach. While reading with RSVP,
a text is displayed sequentially word by word at a fixed location.
However, it is not clear how text locations and presentation
types affect the reading experience in VR. For this purpose, we conducted an explorative study.
For the study, we developed a virtual exhibition, where each exhibition room had a painting and
a label with a textual description at the center of each of the four walls.
The text labels could be displayed with two presentation types,
as a paragraph or using RSVP. With the paragraph presentation type, text was displayed completely,
and participants could read it left to right, top to bottom.
With RSVP, the text was displayed word-by-word and centered around a red pivot letter acting as
a resting point for the participant's eyes while reading. The speed of RSVP was adjusted based on
each participant's regular reading speed. We used three text locations:
world-fixed location, where text was displayed on the environment;
edge-fixed location, where text was attached to the environment with an edge and vertically
tilted to face the user; and head-fixed location, where text was displayed on a head-up display.
For the evaluation, we implemented a primary task for participants that involve common
VR activities. At first, the text labels within the exhibition room were shuffled.
Participants' task was to assign labels to the correct paintings.
To do the task, participants first needed to activate and read a text label and determine
to which painting it belonged. Afterward, participants could switch the labels.
Please refer to the paper for detailed descriptions of the task and the implementation.
Our study had a 2x3 repeated measures design with text presentation type and location
as within-subjects variables. We had 18 participants.
We measured the number of wrong switches of labels as error and the time needed to finish the task,
as well as usability, perceived task load and presence using questionnaires.
Moreover, participants indicated their preference for each condition and provided qualitative feedback.
The results showed that the average number of errors and the TCT were higher with the
paragraph presentation type than the RSVP. The qualitative results revealed that with the
paragraph presentation type, participants did not always read the texts completely
but skim them to find keywords regarding the paintings. As a result, they skipped
some parts of the texts, which might be essential to perform the task. However,
with RSVP, skimming the text was not possible. Moreover, we found that the world-fixed location
increases the perceived task load and decreases user preference rating while reading with RSVP.
As the task used in the study required participants to explore the virtual environment,
they needed to make large attention shifts between texts in the world-fixed location and
the environment. As texts were displayed entirely with the paragraph presentation type, it was easy
for participants to return to the reading flow after these attention shifts and continue reading
from any part of the text. However, reading with RSVP, participants had to continue reading from
the word where the RSVP reading paused. In addition, we found that displaying text
as the paragraph in the head-fixed location increases task load and reduces usability and
user preference rating. As a single word space was needed with the RSVP presentation type,
it facilitated reading while moving in the virtual environment. However, a text displayed as the
paragraph in the head-fixed location partly occluded participants' field of view.
Participants also indicated that they would prefer to read long and important texts as
paragraphs in static environments where the reading is the primary activity.
However, they would favor reading short text using RSVP
in dynamic environments where tasks require detailed attention to the environment.
As the takeaway messages of the study, the results suggest that RSVP should be used
for short texts displayed either in the edge-fixed or in the head-fixed location
if the user needs to move within the virtual environment. Paragraph presentation type with
a world-fixed or edge-fixed location should be used to display long and important texts
if reading is the primary task and the movement in the virtual environment is not required.
Thank you for your attention!