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DES IGNPRINC IPL ESA NDPRACTICES.COM
VOLUME 15 ISSUE 1An International Journal — Annual Review
Design Principles
and Practices
__________________________________________________________________________
A Neurodesign Case StudyMeasuring the Emotional Index for RedesignALESSIO PAOLETTI AND LORENZO IMBESI
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DESIGN PRINCIPLES AN D PRACTICES:
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Design Principles and Practices: An International Journal–Annual Review
Volume 15, Issue 1, 2021, https://designprinciplesandpractices.com
© Common Ground Research Networks, Alessio Paoletti, Lorenzo Imbesi,
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ISSN: 1833-1874 (Print), ISSN: 2473-5736 (Online)
https://doi.org/10.18848/1833-1874/CGP/v15i01/33-44 (Article)
A Neurodesign Case Study: Measuring the
Emotional Index for Redesign
Alessio Paoletti,1 Sapienza University of Rome, Italy
Lorenzo Imbesi, Sapienza University of Rome, Italy
Abstract: Cognitive neuroscience can measure a user’s neurophysiological activities during a product experience with
portable and noninvasive tools. The data collected is summarized in three indices, which express the user’s affective
and cognitive states during the performance of a specific action within an authentic context. This data can represent
additional helpful information for product development. However, it is first necessary to find a link between
neuroscience and design to help designers benefit from this new data. One of the indices measured by neuroscience is
the so-called emotional index, a synthesis of “valence” and “arousal.” Principles of interpretation of the emotional
index from the designer perspective are proposed to guide the designer in improving an existing product and designing
a new one from scratch. The results show how it is possible to identify the design aspects responsible for emotional
index variations. The research limitations lie in the need for further and subsequent neurotests to build a reference case
history.
Keywords: Neurodesign, Neuroscience, User-Centered Design
Introduction
esign as a discipline has always been characterized by a dynamic identity capable of
absorbing new stimuli from reality and returning design solutions that are functional,
semantic, and morphological. The act of designing has never been a gesture resulting
from a sacred fire that is the prerogative of a select few but the personal synthesis of a long and
careful research path. To manage the growing complexity in the field, research uses tools and
methods also designed by other knowledge fields. It is worth exploring the boundaries between
design and other disciplines, both when there are apparent overlapping areas and when common
areas are seen only in future perspectives, as is the case with cognitive neuroscience.
Cognitive neuroscience refers to the analysis of human responses to the external
environment, as has never been achieved before. Let alone from a future perspective, this path
can already immediately interest the designer, especially considering the person’s key role in
human-centered design. Aspects such as workload memory have been known and measured for
some time; these aspects are well-known among those who evaluate a user’s response to a
complex stimulus such as a control panel. But neuroscience research is now also able to
describe a user’s emotional reaction. Ample literature attests to the relevance of the emotional
aspects of the user–product relationship. So, we pose the question of whether it is possible to
create a bridge between neuroscience and design, with the common aim of knowing the user
who is placed at the center of the design process. In this article, we want to report the
comparison between the tools and methods of neuroscience and a review of the literature in
emotion design and highlight that these two fields of knowledge can have common ground.
Emotional Index: Linking between Neuroscience and Design
To identify a link between neuroscience and design, the first step can be neuromarketing, which
currently has more conspicuous scientific literature than that available for neurodesign. This is
1 Corresponding Author: Alessio Paoletti, PDTA Department, Faculty of Architecture, Sapienza University of Rome,
Rome, Italy. email: alessio.paoletti@uniroma1.it
D
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DESIGN PRINCIPLES AND PRACTICES: AN INTERNATIONAL JOURNAL–ANNUAL REVIEW
the first step to describe how neuroscience and design can perform research together around the
problem of user experience. This study’s focus is not the relationship between neuroscience and
marketing, but to point out that it is a starting point. Thanks to the portability of the tools
necessary to measure a user’s neurophysiological responses, it is now possible to simulate the
user’s actions in a real scenario. For instance, it is possible to evaluate the user’s shopping
experience at the point of sale by applying the tools to the user’s body without limiting the
actions; the devices don’t significantly interfere with the quality of the experience.
BrainSign Srl (2018), a spin-off of Sapienza University of Rome, demonstrates excellence
in this field. As shown in Figure 1, BrainSign can conduct neuromarketing evaluations by
measuring—with eye-trackers and other devices described in detail later—what attracts the
user’s attention.
Figure 1: The User Operates in the Real Context of Use, While Portable Devices Detect Changes in Neurophysiological
Data. The Tools, Light and Portable, Do Not Affect the User Experience
Source: BrainSigns
BrainSign can measure neurophysiological reactions with a minimal time lag to when the
user manifests them. The neurocognitive responses are then synthesized into three indices,
namely mental effort, emotional index, and interest. Each index is the result of a series of
specific and independent measurements. With these three indices, a complete picture of the
user’s response is outlined. As mentioned, these tools are now portable and not invasive,
allowing the user to move freely. The user acts in the natural context, thus negating the need to
recreate a laboratory scenario. The goal of this research study is to focus on the emotional index
(EI). This index investigates the user response in terms of the emotional aspects; unlike the ME
index, EI doesn’t consider brain processing but relates to peripheral parameters. When the
subject reacts to the external environment, optimizing time and results, the somatic marker
defined by Damasio (1994) brings past experiences in the decision-making process. The
somatic marker helps to understand how the cognitive and affective responses work together
rather than sequentially. The emotional response can be represented through a few fundamental
dimensions, among which the most commonly accepted are valence, arousal, and approach-
withdrawal.
The valence dimension contrasts states of pleasure (e.g., happy) with states of
displeasure (e.g., sad), and the arousal dimension contrasts states of low arousal (e.g.,
quiet) with states of high arousal (e.g., surprised). Approach motivation is
characterized by tendencies to approach stimuli (e.g., as would likely be facilitated by
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FIRST AUTHOR LAST NAME: ARTICLE TITLE
excitement), whereas avoidance motivation is characterized by tendencies of avoidance
(e.g., as would likely be facilitated by anxiety). (Vecchiato et al. 2014, 857)
Of these four dimensions, two are of interest and constitute the emotional index: valence and
arousal. Valence and arousal variations can depict the user’s emotional states towards a
stimulus. Two neurophysiological variables have been used in scientific literature to measure
valence and arousal: the sweat glands’ activity on the hands, namely the galvanic skin response
(GSR) and the heart rate (HR). The GSR traces changes in arousal, and the HR represents the
valence (Cacioppo et al. 2000; Baumgartner, Esslen, and Jäncke 2006).
By reviewing the scientific literature on emotional design, we have identified some
contributions that allow us to create a bridge between neuroscience and design, associating the
aspects of the product that are most likely the triggers of those values. As a starting point, we
considered Norman’s (2004) research on the three design levels: reflective, behavioral, and
visceral. We then re-read this research in light of the construct of aesthetic pleasantness in
design defined by Hekkert (2006) and considering the research on the concerns of pleasantness
appraisal developed within the research of Desmet (2010). In light of the literature review, and
through a purely theoretical study, we hypothesize that the three constructs of mental effort
(ME), emotional index (EI), and interest (INT) may correspond to the three constructs of
Norman (2004) with an acceptable degree of approximation. Finally, we hypothesize that they
may correspond to three aspects of the product: functional, morphological, and semantic. This
article’s focus is on the emotional index; we show in Figure 2 the hypotheses of correspondence
with aspects of the product. Based on the latter, we propose the following hypothesis: the
emotional index expresses Norman’s behavioral level and is associated with the morphological
sphere.
Figure 2: The Hypotheses of Correspondence with Aspects of the Product
Source: Paoletti
Theories for the Interpretation of the EI
Following the literature review concerning emotional design, we therefore proposed the EI
index as representative of the level of processing that Norman has defined as behavioral. This
level is subconscious and is the place where basic emotions take place. It refers to behaviors for
which users do not need cognitive processes to structure action by action; they are linked to an
action that is well known because users have learned it in the past.
At this level, the mind has a secondary role, and it is connected only to the creation of the
desire to act but not to what action needs to be performed. According to Norman, at this level,
the interaction with the product will lead to positive emotions when the user’s expectations are
confirmed and vice versa, to negative emotions when the expectations are betrayed. Norman’s
behavioral level is the design level at which users evaluate what happened, comparing it to what
they wanted to happen. After hypothesizing a correspondence between the neurophysiological
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DESIGN PRINCIPLES AND PRACTICES: AN INTERNATIONAL JOURNAL–ANNUAL REVIEW
index EI and the Norman behavioral level, we consider the behavioral level as the most relevant
during the so-defined non-instrumental interaction phases.
The non-instrumental interaction is mainly based on the morphological aspects of the
product. For non-instrumental interaction, we refer to the research of Desmet and Hekkert
(2007). Their study describes the product experience as composed of three types of interaction:
instrumental interaction, non-instrumental interaction, and nonphysical interaction. Non-
instrumental interaction usually precedes instrumental interaction. We look at an object, we
anticipate its use, and then we use it. In these non-instrumental interactions, all the senses are
involved: the user looks at the product (sight); if the smell is present, receives it (smell);
appreciates the tactile qualities (touch), and receives sounds (hearing).
We propose some design elements that the designer should consider when designing for
non-instrumental interaction. We name these aspects, relating to the morphological sphere, M1,
M2, M3, and M4, respectively. In light of the above, the four factors can be used in the design
process focused on the morphological sphere and during the inverse process of interpreting the
neurophysiological data relating to EI. Given EI’s nature, to define the four aspects relevant to
the morphological sphere (M1, M2, M3, and M4), we rely on design research that has explored
the principle of pleasantness.
The principle of pleasantness, and pleasure for the senses in research on design, has been
studied in the broader process of user–product interaction in the niche of aesthetic interaction.
Extensive research on the construct of aesthetic pleasure in design was conducted by Hekkert
(2006). We, therefore, refer extensively to this research, adopting it as a starting point for
interpreting EI data from the designer’s perspective. Among other aspects of user–product
interaction, aesthetic interaction can be considered sense gratification (Goldman 2001). Design
literature has explored why certain stimuli can gratify the senses from the perspective of
evolutionary Psychology (Ramachandran and Hirstein 1999). According to evolutionary
Psychology, aesthetic preferences go to those models, and those environmental characteristics,
that are considered beneficial to developing the senses’ functioning and, therefore, survival. The
research already cited by Hekkert (2006) has explored four principles that are transversal to all
senses: maximum effect for minimum means; unity in variety; most advanced, yet acceptable;
and optimal match. As shown below, we will narrow the field of research on the sense of sight,
and we will read these four principles from the Gestalt point of view.
Although the research has explored the cross-cutting principles of aesthetic responses, it does
not mean that all individuals will have the same aesthetic response; this is also influenced by the
interaction between the person and his environment (Berkowitz and Semin 2004). Therefore, the
four principles can be considered the primary references from which the respective cultural and
individual variants are derived. For this reason, different people, but influenced by similar
previous experiences or experiences, will relate to the four principles similarly and will therefore
have similar aesthetic responses: “[…]beauty is maximal when a maximum of effect is attained
with a minimum of means applied” (Boselie and Leeuwenberg 1985, 1).
When users rate a stimulus as pleasant, they consider it positively for their adaptive
functions, for all senses. That’s how we consider a good smell or taste pleasant—they are signs
of their potential benefits for our survival. “these senses are considered the ‘gatekeepers’ of the
body, identifying what is nutritious and should be consumed and detecting what is bad and must
be rejected” (Hekkert 2006, 163). The principles based on which we consider a pleasant
stimulus, in many cases, are specific to the system (the visual system, the olfactory system, etc.)
and can also be specific to the category of stimuli (the aesthetics of the landscape, the aesthetics
of music, etc.) (Hekkert 2006). The merit of Hekkert’s research is to have defined the four
principles which are transversal to all senses. We have narrowed the research field in this
contribution, focusing exclusively on the sensory channel of sight; therefore, considering only
the visual stimuli for their interpretation, we refer to Gestalt. Summarizing, for the
interpretation of EI’s values, our path took the first steps from Hekkert’s (2006) research on the
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FIRST AUTHOR LAST NAME: ARTICLE TITLE
construct of aesthetic pleasure in design; afterward it focused on visual stimuli, and finally re-
read Hekkert’s research from the point of view of Gestalt. This choice to restrict the field of
study to the sense of sight is motivated by the commonly accepted assertion that, among all
other systems, the visual is the main sensory system. For perception, it represents the channel
that transmits most of the information about the external environment regarding obstacles,
passages, distances, actions, and identifying patterns. In this field, Gestalt psychology has
defined the principles that help convey the flow of information. According to Bregman, the
principles or the Gestalt can be seen as “our ‘best guesses’ to order the stream of auditory
information” (Bregman 1990). Based on the literature cited, the four aspects relevant to the
morphological sphere are M1 metaphors, M2 relationships, M3 typicality and novelty, and M4
consistency of messages, as shown in Figure 3.
Figure 3: The Picture Shows the Four Aspects Relevant to the Morphological Sphere, Which We Consider Decisive during
Non-instrumental Interaction. They Can Be Used Both in Terms of Design and in Terms of Interpretation of the EI
Source: Paoletti
M1 Metaphors
Based on the assumption that the sensory system prefers a perceivable stimulus in the most
economical way possible, we try to transpose this principle on a design stimulus. Considering a
stimulus that transmits most of the information using few resources, we can imagine that this
leads to greater aesthetic pleasure. Specifically, Gestalt psychology has defined disjunctive
ambiguity as unfavorable to beauty and, therefore, aesthetic experience; conversely, conjunctive
ambiguity is favorable to beauty and aesthetic experience. An example of disjunctive ambiguity
is the rabbit-duck illusion, shown in Figure 4.
Figure 4: The Illusion of the Rabbit and the Duck, Designed in 1892 by the American Psychologist Joseph Jastrow, Is a
Clear Example of Disjunctive Ambiguity That Increases the Effort, Resources, and Capacity of the Brain Users Must
Spend on Its Interpretation. The Disjunctive Ambiguity Negatively Affects the Aesthetic Experience
Source: Paoletti
The observer has to spend more resources on perception and brain capacity to counteract
the ambiguity. On the contrary, an example of conjunctive ambiguity is the study of polygons
conducted by Boselie and Leeuwenberg (1985). They highlighted the relationship between
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DESIGN PRINCIPLES AND PRACTICES: AN INTERNATIONAL JOURNAL–ANNUAL REVIEW
beauty and complexity, showing preferences for specific proportions of simple figures over
others. It therefore appears evident that if the stimulus conveys metaphors that the users
correctly decipher, these positively affect the aesthetic experience because the metaphors are
recognized as cheap and efficient in bringing a meaning (Ramachandran and Hirstein 1999).
“The power of metaphor lies in its ability to relate two distinct entities, which in turn initiates
the production of new and deeper meanings” (Cila, Hekkert, and Visch 2014, 1). An example of
metaphors in design is shown in Figure 5.
Figure 5: Left Image: The Philips Senseo® Coffee Machine Uses the Embodied Metaphor of a Hunched Servant
Serving Coffee. Right Image: Metaphors Economically and Efficiently Convey a Wealth of Meaning. The Metaphor of
a Secure Memory Stick Generated with a Padlock Metaphor Gives a Deeper and More Direct Meaning
Source: Left Image Philips; Right Image Downloaded from http://www.keyables.com/2013/01/protect-pendrive-data-
with-truecrypt-password.html
According to Cila, Hekkert, and Visch (2014), the constituent elements of a product
metaphor are salience and relationship. A designer who wants to generate a product metaphor
needs to identify the source’s property that conveys the desired meaning, verify that it has a
high salience, and, finally, verify that it is related to the target product. The first principle can be
considered all-encompassing for all the following principles. As seen, the first principle from
sensory stimulation was expressed by the sense of sight, but it can be adopted for all other
sensory domains (Figure 6).
Figure 6: Example of Metaphor in Product Design: a Usb Pen That Communicates Security. Designers Must Identify
the Source That Conveys the Meaning They Intend to Assign to the Product, Selecting It Based on Its Salience and
Relationship with the Final Product to Generate a Product Metaphor
Source: Cila, Hekkert, and Visch 2014
According to the metaphors principle, designers who want to interpret a negative/positive
value of EI should ask themselves:
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a. Is the stimulus ambiguous and therefore not perceived in the cheapest way possible? The
principles of Gestalt psychology are the references with which to compare the stimulus.
b. Are there clear metaphors that economically and efficiently convey a wealth of meaning?
Participants in neurophysiological trials should be interviewed via self-reporting tools, such as
semi-structured interviews, to highlight the metaphors they have found. The survey results
should be the references for interpreting EI measures.
A research tool to collect textual data from users, also used in the design field, is the semi-
structured interview. That would allow collecting textual data that can then be compared with
the neurophysiological data measured. Galletta (2013) discussed the qualitative research method
and its critical steps in a practical manual.
M2 Relationships
Recognizing the relationships between objects has the advantage of reducing perceptual efforts.
To optimize the brain’s efforts, resources, and abilities, sensory systems have developed the so-
called individuation of order in chaos, or unity in variety, acquiring the tendency to group and
recognize relationships. This principle has been explored by Gestalt psychology and
neuroscientists Ramachandran and Hirstein (1999). According to these studies, the relevant
laws for identifying relationships are symmetry, good continuation, closure, peak shift,
isolation, contrast, and solving puzzles (Ramachandran and Hirstein 1999). While Gestalt
psychology has defined how individuals prefer simplicity, Ramachandran and Hirstein also
demonstrated how resource-demanding stimuli could lead to pleasurable effects. An example is
shown in Figure 7.
Figure 7: Left: Peak Shift Effect, According to Which Super-Normal Stimuli Are More Exciting for Brain Areas Than
Natural Ones, Leading to the Judgment of Pleasantness, Also According to the Principle of Solving Puzzles. Right:
Contrast Effect, in Which Luminance Affects the Perception of the Boundary between Vertical and Horizontal Lines
Source: Ramachandran and Hirstein 1999
Describing the dashed image of the Dalmatian in Figure 7, relevant for the peak shift effect,
Ramachandran and Hirstein observe:
Initially seen as a jumble of splotches, once the Dalmatian is seen, its spots are
grouped—a pleasing effect, caused perhaps by activation of the limbic system by
temporal lobe cortex […] Hence a puzzle picture (or one in which meaning is implied
rather than explicit) may paradoxically be more alluring than one in which the message
is obvious. (Ramachandran and Hirstein 1999, 21)
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The contrast effect also helps the individual to find relationships between objects, which, for
example, would not have a belonging relationship but are perceived as linked by having
similarities of positioning. Most research has focused on the visual perceptual system. Similar
laws have been found in auditory information, as music is also often based on similar principles
of repetition, closure, and similarity.
Following the principle of the relationship, designers who want to interpret a
negative/positive value of EI should ask themselves:
a. Does the stimulus have an information structure that is too complex?
b. Is the structure consistent with the necessary information? The principles of Gestalt
psychology are the references with which to compare the stimulus.
c. Is the stimulus monotonous, too obvious, unsatisfactory for the peak shift effect and the need
for puzzle-solving? The principles defined in Ramachandran and Hirstein’s research are the
references for interpreting the data.
M3 Typicality and Novelty
Designer Raymond Loewy defined the MAYA principle (most advanced yet acceptable)
according to which the stimulus that optimally combines typicality and novelty leads to the
maximum pleasure of the senses. That happens because, for adaptive reasons, the individual
prefers family stimuli that lead to safe choices but, at the same time, and as has been observed
in children, the human being needs novelty to facilitate learning and to absorb the effects of
boredom and saturation (Martindale 1990).
The relationships between typicality and novelty in product design are relevant to aesthetic
preference but are mutually exclusive (Hekkert, Snelders, and Van Wieringen 2003). Research
has shown that the choices are for those products with a balanced combination of typicality and
novelty. To sum up, we prefer new designs as long as the novelty character does not negate
typicality. This principle is also valid for the other perceptual systems; for example, even in
music, the role of familiarity (Gaver and Mandler 1987) and typicality (Repp 1997) has been
highlighted. An example of a combination of familiarity and novelty in music is the remix of
old songs.
Based on the typicality and novelty principle, designers who want to interpret a
negative/positive value of EI should ask themselves:
a. What is the degree of typicality and novelty in the stimulus?
b. To what extent is the stimulus recognized as a relevant example of the category in
question?
Participants in neurophysiological trials should be interviewed using self-reporting tools
such as semi-structured interviews to highlight the typicality/novelty. The surveys’ results
should be the references for interpreting the data.
M4 Consistency of Messages
A design product can be a complex stimulus that involves the senses in a multimodal way in the
process of perception. To increase ease of identification, essential for survival, products that
transmit the same message through different sensory channels, one consistent with the other, are
more easily identifiable (Zellner, Bartoli, and Eckard 1991). Therefore, they are perceived as
more pleasant during the aesthetic experience. Furthermore, the consistency as an aesthetic
pleasure trigger is appreciated when present between the different sensory channels and when it
is present between the message sent by the sensory channels and the given product. “[...] the
famous dictum ‘form follows function’ [...] could now easily be transformed to the other senses
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FIRST AUTHOR LAST NAME: ARTICLE TITLE
in ‘sound/touch/smell follows function’ ” (Hekkert 2006). By the term function, the researchers
understood not only utilitarian functions but also all the other functions that a product can
satisfy to enrich, inspire, strengthen the user’s identity, etc. A good design makes all sensory
messages harmonious and congruent with the product’s primary function. Therefore, it is
essential to identify the function of the product considered to be the main one. The message sent
to the sensory system should then be consistent and, as a consequence, generate a pleasant
aesthetic experience. But the primary function of the product may vary according to the
interaction phase considered. Following the consistency of messages principle, designers who
want to interpret a negative/positive value of EI should ask themselves:
a. When the EI is measured, what is the significant function that the user considers the
relevant message?
b. Which messages do the sensory systems transmit?
c. Are these messages consistent with each other?
Case Study—EI Interpretation
In the following case study, we show how to interpret EI’s neurophysiological data from the
design perspective. Neurophysiological measurements have been performed in the labs of
BrainSigns, the spin-off from Sapienza University. The stimuli selected for the experiments
were packaging from the food and beverage industry. We also used flexible packaging since
this will be one of the most relevant packaging industry innovations in the coming years
(TechNavio 2016). We used as a stimulus the pouch shown in Figure 8. The stimuli were
analyzed, proposing to the users three similar pouches: the products 1A, 1B, and 1C shown in
the picture as illustrations.
Figure 8: The Stimuli Used in the Case Study Were Packaging from the Food and Beverage Industry, Namely Pouches.
The Photographic Image on the Left Shows a Generic Container Used as a Stimulus. For Reasons of Confidentiality, the
Actual Photos of the Products Used as Stimuli Are Not Shown. There Were Three Products, Similar to the One in the
Picture But Different from Each Other in the Material’s Opacity-Transparency and Consistency. The Three Stimuli Are
Shown as Illustrations 1A, 1B, and 1C
Source: Paoletti
We can’t show real pictures of the products for confidentiality reasons of BrainSigns and
its clients. The three pouches don’t have significant differences in dimensions, weight, and
geometry. They differ in the nature of their contents in terms of density (but have a similar
smell) and have different materials that affect the package’s transparency. Therefore, the
illustrations in Figure 8 show the inner content (the blue drop) with a solid line in stimulus 1A
and a dotted line for stimulus 1B to indicate whether the internal content is visible or not. In
stimulus 1C, the content was not liquid and was not visible. Therefore, the illustration depicts
drops and small cubes with dotted lines. Even if the products were very similar, they elicited
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DESIGN PRINCIPLES AND PRACTICES: AN INTERNATIONAL JOURNAL–ANNUAL REVIEW
very different EI values during the instrumental phases, precisely when they needed to tear the
label off and transfer the inner content to a given container.
The stimuli 1A and 1B elicited similar negative EI values during the first instrumental
interaction of tearing the label off, as shown in Figure 9. On the contrary, they produced
different EI values during the second instrumental interaction, where the users had to transfer
the inner content. By following the interpretation principles defined before and described in the
previous paragraph, we found principle M4—consistency of messages—to be the most suitable
for data interpretation. It highlighted a lack of consistency of the messages, specifically, the
message conveyed by the sensory systems of sight and touch. Such a lack of consistency is the
most probable reason for the variation of EI values.
Figure 9: Stimuli 1A and 1B Elicited Similar Negative EI Values during the First Instrumental Interaction of Tearing
the Label Off. By Following the Interpretation Principles Defined Before and Described in the Previous Section, We
Found Principle M4—Consistency of Messages—to Be the Most Suitable for Data Interpretation. It Highlighted a Lack
of Consistency of the Messages, Specifically, the Message Conveyed by the Sensory Systems of Sight and Touch
Source: Paoletti
Stimuli 1B and 1C are similar in size, weight, geometry, and package opacity. They differ
in the nature of the internal contents: liquid in stimulus 1B and semi-liquid in stimulus 1C.
Packaging 1C sends more feedback to the user about the location of the content. The content is
partially solid, and the user’s haptic system receives this information, which is not present in
1B. This lack of information in product 1B is detected with negative EI values, which are
negative affective states. By following the principle M4—consistency of messages—we
interpreted this difference in the neurophysiological data, attributing it to a specific product’s
characteristic. In this way, we highlighted the packaging’s area of improvement from the
designer’s perspective.
Conclusion
In this article, we have proposed a correspondence between one of the neurophysiological
indices measured by neuroscience and one of the processing levels defined by Norman (2004)
in the context of emotional design. We proposed that through the emotional index measured on
the user, one can measure Norman’s behavioral level. Furthermore, that level is the most
relevant in the type of interaction defined as non-instrumental by Desmet and Hekkert (2007)
research. Combining research on emotional design, we have interpreted the data in a design key,
identifying the aspects of the product that can be improved, increasing the quality of the user
experience in terms of EI and behavioral level. Finally, we demonstrated a real case study.
In the case study, the experiment’s goal was to test the interpretation principles showed in
the previous paragraphs. However, this opens up future paths of research such as verifying the
specific trends. The results obtained from applying the interpretation principles should be
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FIRST AUTHOR LAST NAME: ARTICLE TITLE
revalidated with new neurotests in the future. The product modified by following the
interpretation should be given as stimulus again to compare the product ante and the product
post. After the validation of the principles, it should also be applied in critical contexts in which
the quality of the user–product relationship can have more significant consequences, such as in
the biomedical area. In conclusion, the interpretation’s principles help us think about which
aspect of the product may be considered for improvement; still, choosing where to operate and
how to redesign the stimulus remains at the designer’s discretion.
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ABOUT THE AUTHORS
Alessio Paoletti: Adjunct Professor, PDTA Department, Sapienza University of Rome, Rome,
Italy
Lorenzo Imbesi: Full Professor, PDTA Department, Sapienza University of Rome, Rome, Italy
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ISSN 1833-1874
Design Principles and Practices: An International Journal—Annual Review
explores the meaning and purpose of "design," as well as speaking in grounded ways about the task of design and the use of designed artifacts. The resulting conversations weave between the theoretical and the empirical, research and application, market pragmatics and social idealism.In professional and disciplinary terms, the journal traverses a broad sweep to construct a transdisciplinary dialogue which encompasses the perspectives and practices of: anthropology, architecture, art, artificial intelligence, business, cognitive science, communication studies, computer science, cultural studies, design studies, education, e-learning, engineering, ergonomics, fashion, graphic design, history, information systems, industrial design, industrial engineering, instructional design, interior design, interaction design, interface design, journalism, landscape architecture, law, linguistics and semiotics, management, media and entertainment, psychology, sociology, software engineering, technical communication, telecommunications, urban planning, and visual design.
Design Principles and Practices: An International Journal—Annual Review
, consists of articles considered to be of wide interest across the field. Five thematically focused journals also serve this Research Network:
•
The International Journal of Design Education• The International Journal of Design in Society• The International Journal of Design Management and Professional Practice• The International Journal of Designed Objects• The International Journal of Visual DesignDesign Principles and Practices: An International Journal—Annual Review
, is a peer-reviewed, scholarly journal.
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