2022 8th International HCI and UX Conference in Indonesia (CHIuXiD) | 978-1-6654-7664-5/22/$31.00 ©2022 IEEE | DOI: 10.1109/CHIuXiD57244.2022.10009797“Ah-aloud”:
Method for Evaluating Cognitive Processes
Occurring During Tasks from Vocal Information
Takuya Kawashima
Frontier Media Science Program,
Meiji University
Nakano, Tokyo, Japan
cs212007@meiji.ac.jp

Abstract—The think-aloud method, in which users verbalize
thoughts generated during a task, provides insight into users'
task-directed cognitive processes. However, verbalization
during a task is burdensome and reactive, and the words used
and amount of speech vary between users. To overcome thischallenge, we propose the ah-aloud method in this study,
wherein cognitive processes are expressed solely using “ah” andevaluated through vocal volume and intonation. Experiments
compared to think-aloud using video game tasks with Japanesespeaking participants showed negligible difference in the
reduction of verbalization burden and reactivity. It seems thatpeople are very different regarding whether think-aloud or ahaloud is easier. However, we found that ah-aloud can express
various feelings, so we will establish ah-aloud position bycomparing it with experimental methods to evaluate feelings,
such as physiological signal measurement. We also discuss therecommended methods for obtaining think-aloud data.
Additionally, we surveyed the literature pertaining to English
interjections and discussed the possibility of extending thismethod to other languages.
Keywords—think-aloud, cognitive processes, experimental
method, evaluation

I. INTRODUCTION
The think-aloud method [1] is an experimental method thatallows users to verbalize thoughts generated during a task.
Concurrent think-aloud is the only method that can completelyreflect thoughts and mental states generated during task
execution because retrospective verbalization may cause
falsification and loss of recollection [2, 3]. The think-aloudmethod has been applied in diverse research fields, including
usability testing [4], body and strategy perception in sports [5],and translation studies [3].
However, this method burdens verbalization and reactivity
and verbalizing while performing a task is challenging. As
speaking while thinking is an unusual behavior that is not
usually performed, the amount of speech may be extremely
small for some participants [6]. The solution to this problem
is to have the participants practice thinking aloud in advance[7] or prepare a closed environment for them [8]. However,such a practice often does not work in a limited time, andpreparing a strictly closed environment is difficult. The
collected speech data are often analyzed qualitatively;
however, differences in the amount of speech and words
spoken by the participants render the analysis difficult. Somestudies have reported the reactivity of the think-aloud method.
It influences performance and task completion time,
particularly in tasks with a high cognitive load and complexity[9, 10].

Keita Watanabe
Department of Frontier Media Science,
Meiji University
Nakano, Tokyo, Japankeita_w@meiji.ac.jp

Fig. 1.
“Ah-aloud”: Experimental method in which one talks about whatcomes to mind while performing a task using only “ah.”To overcome these shortcomings, we propose ah-aloudmethod in this study. This method helps determine thecognitive processes that occur during a task, while reducing
the burden of verbalization and reactivity. This is a method inwhich all thoughts that occur during task execution are
expressed using solely the sound “ah.” We believe that
restricting participants to a single sound mitigates theaforementioned challenges. In Japanese, the interjection “ah”
is used as subjective expression, such as feelings and thoughtprocesses, e.g., “Ah, naruhodo!” (“Oh, I see!”) or “Ahh,yuutsu da...” (“Ugh, I’m depressed...”) [11]. Sudo [12]classified functions according to accent and intonation, statingthat descending tones imply approval or remembrance,
whereas descending to slightly ascending tones implies
discouragement or dissatisfaction. It has many other meanings
and functions, including doubt and discovery. Therefore, thesound “ah” is suitable for expressing the cognitive processes.
We conducted an experiment with Japanese-speaking
participants to demonstrate the viability of the proposed
strategy as a novel experimental method for evaluating
cognitive processes. Based on the results of this experiment,
we discuss its validity as an experimental method forevaluating cognitive processes. In addition, we examinedinterjections, particularly the English “ah,” which can express
a wide range of cognitive processes.

Fig. 2.
Experimental Environment: The experimenter is on the other sideof the white partition during the task so that the participants can speak easily.

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II. RELATED WORKS
A. Experimental Methods to Evaluate Cognitive Processes
In this section, we introduce experimental methods otherthan the think-aloud method to evaluate cognitive processes,
and show the differences between these methods and the
proposed method.
In contrast to the think-aloud method, in which
participants talk to themselves, there is a “question-asking
protocol” [6], wherein the experimenter asks questions to theparticipants and collects speech data as if it were a dialogue.
Although this method naturally encourages speech, it isdifficult to appropriately set the content and timing of theexperimenter’s questions. Boren et al. [13] suggested speechcommunication, in which the experimenter uttersacknowledgement tokens. This is difficult to implement
correctly, because it requires an appropriate response from theexperimenter. Another experimental method that encourages
participants to speak while interacting with each other is the
dialogue method (Taiwa Ho) [8]. This is not a dialogue
between an experimenter and a participant but a dialogue
between multiple participants. It is necessary to consider the
relationship between the experiment, participants, and setting
the goal of the task, as it is difficult to obtain the appropriate
speech data for which the experimenter aims. This method
facilitates the experimental setup and can be used to obtain
spontaneous speech data from participants.
A retrospective method is described at the beginning of
this section. This is also called aided subsequent verbal
protocol [14]. In this method, the participants are recorded onvideo while performing a task and are asked to talk about theirintentions and thoughts while watching the video after the task
is completed. Because the participants were not asked to speak
during the task, there was no concern about affecting their task
performance. Haak et al. [9] compared speech concurrent withthe task (CTA: concurrent think-aloud) and speech whilereflecting on the task (RTA: retrospective think-aloud) in ausability test and established the high reactivity of CTA.
However, after performing a task that requires more than 10 s,
it is possible that all but some of the information transferredfrom short-to long-term memory is forgotten. In such cases,
posterior verbalization is difficult, and the data are known to
be incomplete. This is a new method for retrieving
information from short-term memory with low reactivity.

Fig. 3. Recorded using Multi View Recorder: screen of video game (topleft), frequency domain of participant's voice(top right), participant'sface(bottom left), and participant's hand operating the controller(bottom
right): The participants are asked to watch and reflect on what comes to mind.

The single pattern increases the burden of converting any
word that comes to mind into “ah,” which may shift theattention of the user from the task to vocalization. Therefore,
we propose a continuous pattern that enables users to vocalize
their feelings subconsciously. Cognitive processes areevaluated by changes in loudness and tone that occur duringcontinuous vocalization.
IV. METHODOLOGY
We experimented with three different patterns: the two
proposed in Chapter III, plus the think-aloud pattern, on
Japanese-speaking participants to evaluate whether they could
reduce the burden of verbalization and reactivity, and what
they could express with “ah”. As detailed in the next section,
we used two video games as the tasks. The participants
experimented with three patterns in two tasks for a total of six
trials. In the continuous pattern, the participants were allowed
to pause for breath as necessary.
Think-aloud pattern: Participants were instructed
to verbalize their what come to mind.
Twelve male and female participants, university students
between the ages of 21 and 24, were chosen. Because we
wanted to acquire a diverse experience, we did not limit theirpersonalities, skills in video games, and experience with thistask.

III. PROPOSAL: AH-ALOUD
We propose a new method that can completely reflect thecognitive processes during task execution. As shown in Fig.
1, this is the method in which all thoughts and feelings that
occur during task execution are expressed using solely thesound “ah.” This may lead to task-directed cognitive
processes such as discovery, approval, and incomprehensionof the task, as in think-aloud.
We proposed the following two patterns for the use of“ah” during a task.
Single pattern: The participants were instructed torepresent their what come to mind solely using “ah.”Continuous pattern: The participants were
instructed to vocalize “ah~” continuously.

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Fig. 5. Spectrogram of the utterances by one participant
The single pattern(top) and the think-aloud pattern (bottom)

Fig. 4. Burdens of verbalization(left) and reactivity(right): questionnaire
results

A. Selection of Tasks
The think-aloud method has been used for relatively selfpaced tasks, such as the usability evaluation of application
concepts and navigation and strategy analysis in sports.
However, reducing the burden of verbalization may beeffective for tasks with a high cognitive load, such as playing
video games or sports, where the pace of the task may beremoved. In this study, we used a video game task. Two video
games, Sliding Penguin and Minimum Tennis from OpenVideo Game Library1, were used. Escape Fish was used topractice the utterances of each pattern.

watch the recording of the experiment using Multi
View Recorder2 (Fig. 3) and reflect on what was onyour mind.
8)

Repeat 5) - 7) with another video game.

9)

Answer the questionnaire using Google Forms.

C. Results
Upon completing the tasks, participants answered a
subjective questionnaire on the burden of verbalization andreactivity using a seven-point Likert scale. Fig. 4 shows thequestions and box-and-whisker diagram of their answers. The
questionnaire results were analyzed using two-way ANOVA.

1)

Receive an explanation of the experiment and how
the data to be collected will be handled, and sign theexperimental consent form.

2)

Receive an explanation of the three patterns to betested.

3)

Receive an explanation of the rules and operations of
the video game.

4)

Practice each of the three patterns once using thevideo game for practice.

5)

Receive an explanation of the rules and operations of
the video game.

6)

Practice the video game.

No significant differences were found for either of thequestionnaire items. In other words, ah-aloud did not reducethe burden of verbalization and reactivity compared withthink-aloud. Especially in the continuous pattern, the variance
was large, and opinions were divided among the participants.
In the open-ended descriptions in the questionnaire, theparticipants claimed about the continuous pattern that “I could
concentrate on the play because I could just say ‘ah,” ’ “Bycontinuously saying it out loud, I was able to generate it in
response to changes in my feelings,” and “I didn't have to think
about words, so it was easier to play than the think-aloud
pattern.” The effectiveness of the continuous pattern was
evaluated as hypothesized. Whereas, the breathing problem
was a major issue: “It was physically burdensome to breathe,”“I was a little tired in terms of breathing and vocalization,”and “It was very difficult to keep saying things all the time.”
The participants claimed about the single pattern that “I oftensay ‘ah’ when I make an operational missing or when I am
surprised, so it was not that difficult. In fact, because I
vocalized naturally, I felt like it was the most natural of thethree patterns,” “I did not know what it would be like toconvert the word to ‘ah’ at first, but once I tried it, it wentsmoothly,” and “I did not feel burdened because I just said 'ah'at my leisure." On the other hand, negative claim were also
obtained: “I was a little confused about when to say ‘ah,” ’“When I was concentrating on the game or thinking about thenext development, I sometimes forgot to say ‘ah’ and becamesilent,” and “While it was easy to respond, it was difficult to
express what I was thinking about,” and “It was burdensome
to convert every word that came to mind into ‘ah. ’”

7)The experimental task was performed using a video
game for each of the three patterns.
After the trials of single and continuous patterns,

Furthermore, in both patterns, the differences in the time
and tone of “ah” could express various thoughts and feelings.
The participants reflected on their thoughts and feelings after

Sliding Penguin is a driving game in which penguins slide
on ice. It was selected because it is thrilling, and feelings
easily come to mind. Minimum Tennis is a simple tennis
game. It was selected because the keyboard operation method
is complex, and thoughts about the operation and gamestrategy easily come to mind. To avoid the influence of fatigue
caused by a continuous pattern, we set the number of games
to a minimum of one.
B. Procedure
The experimental procedure for the participants was asfollows. The order of turning trials was counterbalanced. To
facilitate speech, a partition was set up, as shown in Fig. 2, tomake participants unaware of the experimenter.

1
Library with open video-games and experimental support tools forresearchers (https://open-video-game-library.github.io/info/)2

https://open-video-game-library.github.io/multi-view-recorder/

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the task, and in many cases, the experimenter could determine
the meaning without asking for the participants' opinions. Joy
was expressed in various ways, some in small increments andothers in up and down tones. However, by analyzing the gamescreen and facial expressions together, the experimenter wasable to easily determine their feelings. The tone was often
lowered to express relief; thus, it was easy to detect theemotional state of relief using intonation alone. The tone while
expressing sadness increased as if to say “I’ve done it,” andconversely, the tone while expressing sadness decreased as if
in despair. The magnitudes of these feelings varied but wereeasier to understand when analyzed in conjunction with thegame situation. Surprise and impatient tones often rose
sharply in tone and loudness. Some of the same rapid increases
in tone expressed interrogation because of a lack ofunderstanding of the game specifications. Some of theawareness tone responses were nuanced, as if they weresatisfied, whereas others contained a hint of surprise.
Whereas, the contemplation tone was often constant and could
not be determined from voice information alone. In somecases, the participants did not vocalize their thoughts, eventhough they were thinking about something. In particular,when the concentration was high, vocalizations seemed to bedifficult to produce. Even during continuous vocalization,some participants experienced vocalizations that wereinterrupted during important scenes in the video game.
Although the subjective evaluation questionnaire suggested a
reduction in reactivity, some participants showed reactivity.
There were instances of “ah” vocalizations regardless of thethoughts and feelings at the time, such as using “ah” tomeasure the timing of hitting the ball and adjusting the
vocalizations to avoid forceful manipulation. In addition,some participants experienced real tennis, and their habit of
vocalizing when hitting the ball was observed in the tennis
game. Because these vocalizations affected the task, it isnecessary to consider countermeasures in the future.
There was no significant difference in the amount ofspeech between the patterns. As an example, a spectrogram ofthe speech produced by Ocenaudio3 for one participant while
playing Sliding Penguin is shown in Fig. 5. The upper panel
shows a single pattern, and the lower panel shows a thinkaloud pattern. Although it was not possible to compare theamount of speech because of the differences in the content ofspeech and the duration of play, the amount of speech did not
become extremely small for either the participant or thepattern.
D. Discussion
The reason the burden of verbalization and reactivity could
not be reduced compared to think-aloud is thought to be a
problem with the instructions. In the single pattern, theparticipants were instructed to represent their what come tomind solely using “ah.” We wanted the participants to express
their cognitive processes, such as agreement and questioning,as interjections used on a daily basis, but they tried to convert
every word into “ah.” We need to make what we want theparticipants to express clear and find an appropriate
instruction, for example, “Please represent ‘ah’ as if you giveback-channel feedback to the task.” First, it may not besuitable for obtaining data targeted by think-aloud. It isnecessary to clarify the type of data that should beappropriately obtained. This is discussed in detail in Section
V. In addition, in Minimum Tennis, “ah” was used to figure
3

right time when hitting a ball. Such use of “ah” does notprovide meaningful data, so we should had instructed inadvance not to use it.
The task design is also problematic. We chose two video
games because thoughts and feelings easily come to mind, andparticipants completed a questionnaire after playing bothvideo games. We should have experimented separately toinvestigate what kind of task aloud was suitable. Sliding
Penguin was more likely to express feelings, and Minimum
Tennis was more likely to express thoughts, but it was difficult
to determine the specific thoughts based on “ah” alone. From
this experiment, it appears that the continuous pattern issuitable for tasks that require high concentration or are in ashort period of time, whereas the single pattern is suitable forother tasks. Unlike the continuous pattern, the single patternmakes it easier to understand the triggers of thoughts andfeelings; therefore, it is better to use a single pattern.
Additional experiments should be conducted in the future toclarify the tasks that are suitable for this method.
In this study, the analysis was conducted by subjective
questionnaire evaluation; however, as in previous studies [9],an objective analysis of the task data may show reductions in
the burdens of verbalization and reactivity. Burdens of
verbalization can use data such as the completion time of atask or, in the case of usability testing, the number of problems
detected. However, the task completion time was preferred not
to compare because it depended more on video game skills
than on vocalization skills. Reactivity was highlighted by theretrospective speech data in this study; in the future, the thinkaloud pattern will also be analyzed. Thus, objective analysis
might produce results that would reduce the burden ofverbalization and reactivity.
V. LIMITATION AND FUTURE WORK
A. The method to obtain feelings rather than thoughts
We expected to obtain task-directed cognitive processes,
such as discovery, approval, and incomprehension, but we
obtained far more feelings. Essentially, feelings are excluded
in order to analyze cognitive processes [1], but this was notdone in this study. Ah-aloud is more like a method that
evaluates feelings from physiological signals, such as
electrocardiograms, skin temperature variation, and EEG
frequencies (e.g., [15, 16]), rather than thoughts that areclosely tied to cognitive processes. Ah-aloud is different fromphysiological signals in that it prompts spontaneous action(vocalization), but may be able to capture trivial feelings that
do not appear in physiological signals. We will clarify the
position of this method by comparing it with experimental
and analytical methods that use physiological signals.
B. Combination with other methods
As mentioned in Chapter IV, many feelings could beobtained, but if you want to know more about the cognitive
processes, you may want to combine retrospective thinkaloud, as we did in our experiment. Inherently, retrospective
methods may lose vital information that was being consideredduring the task [2]. However, they greatly depend on thestimuli that participants receive to help them recall theirthoughts [9]. Therefore, “ah” may provide stimuli forrecalling the cognitive process during the task. Its
effectiveness as a stimulus should be verified in future studies.

https://www.ocenaudio.com/

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Eye-tracking measurements may be also valid. Eye
tracking has already been validated in combination withthink-aloud [17], which provides additional information. In
ah-aloud, Eye-tracking could reveal what the vocalization “ah”
is in reaction to.
C. Potential Application to English
Because this method utilizes the Japanese “ah” to express
various feelings, it is unknown whether this method can beapplied to participants whose native language is not Japanese.
However, the limitation of expression to a single soundreduces the burden of verbalization and reactivity; therefore,a single sound must be selected for each language. Although“ah” in English is similarly pronounced as “ah” in Japanese, it
is unclear whether English speakers naturally express various
feelings with this sound.
In his attempt to classify interjections in English bymeaning, Jovanović [18] stated that “ah” indicates delight,
pain, or surprise, “aargh” indicates disgust, and “ach”
indicates delight. There are other examples of expressing
awareness and changing nuances through intonation in
English [19]. Although this strategy is applicable to Englishspeaking countries, further experiments with English speakers
are necessary for verification.
VI. CONCLUSION
Here, we proposed the ah-aloud method in which users
were asked to represent what comes to their minds with “ah,”and the cognitive processes were thus evaluated using thephonetic information. We conducted the experiment using avideo game as the task and analyzed a questionnaire to see if
ah-aloud could reduce burdens of verbalization and reactivity
compared to the think-aloud method, and found that it could
not. This may be due to the poor selection of tasks andinstructions for the participants, so it is necessary to seek anappropriate experimental environment through further
experiments. We found that rich feelings could be evaluated.
In the future, it will be necessary to clarify where ah-aloudstands compared to experimental methods that can assess
feelings, such as physiological signal measurement. We will
also experiment with English-speaking participants toinvestigate whether the method is valid for them.
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