Uncanny valley effect: A qualitative synthesis of empirical research to assess the suitability of using virtual faces in psychological research

Recently, virtual faces are often used as stimuli to replace traditional photographs in human face perception studies. However, despite being increasingly human-like and realistic, they still present flaws in their aspects that might elicit eerie feelings in the observers, known as the Uncanny Valley (UV) effect. The current systematic review offers a qualitative synthesis of empirical studies investigating observers' subjective experience with virtual compared to real faces to discuss the possible challenges that the UV effect poses when virtual faces are used as stimuli to study face perception. Results: revealed that virtual faces are judged eerier than real faces. Perception of uncanniness represents a challenge in face perception research as it has been associated with negative emotions and avoidance behaviors that might influence observers' responses to these stimuli. Also, observers perceive virtual faces as more deviating from familiar patterns than real faces. Lower perceptual familiarity might have several implications in face perception research, as virtual faces might be considered as a category of stimuli distinct from real faces and therefore processed less efficiently. In conclusion, our findings suggest that researchers should be cautious in using these stimuli to study face perception

Creepy cats and strange high houses: Support for configural processing in testing predictions of nine uncanny valley theories

In 1970, Masahiro Mori proposed the uncanny valley (UV), a region in a human-likeness continuum where an entity risks eliciting a cold, eerie, repellent feeling. Recent studies have shown that this feeling can be elicited by entities modeled not only on humans but also nonhuman animals. The perceptual and cognitive mechanisms underlying the UV effect are not well understood, although many theories have been proposed to explain them. To test the predictions of nine classes of theories, a within-subjects experiment was conducted with 136 participants. The theories’ predictions were compared with ratings of 10 classes of stimuli on eeriness and coldness indices. One type of theory, configural processing, predicted eight out of nine significant effects. Atypicality, in its extended form, in which the uncanny valley effect is amplified by the stimulus appearing more human, also predicted eight. Threat avoidance predicted seven; atypicality, perceptual mismatch, and mismatch+ predicted six; category+, novelty avoidance, mate selection, and psychopathy avoidance predicted five; and category uncertainty predicted three. Empathy's main prediction was not supported. Given that the number of significant effects predicted depends partly on our choice of hypotheses, a detailed consideration of each result is advised. We do, however, note the methodological value of examining many competing theories in the same experiment

Circling Around the Uncanny Valley: Design Principles for Research Into the Relation Between Human Likeness and Eeriness

The uncanny valley effect (UVE) is a negative emotional response experienced when encountering entities that appear almost human. Research on the UVE typically investigates individual, or collections of, near human entities but may be prone to methodological circularity unless the properties that give rise to the emotional response are appropriately defined and quantified. In addition, many studies do not sufficiently control the variation in human likeness portrayed in stimulus images, meaning that the nature of stimuli that elicit the UVE is also not well defined or quantified. This article describes design criteria for UVE research to overcome the above problems by measuring three variables (human likeness, eeriness, and emotional response) and by using stimuli spanning the artificial to human continuum. These criteria allow results to be plotted and compared with the hypothesized uncanny valley curve and any effect observed can be quantified. The above criteria were applied to the methods used in a subset of existing UVE studies. Although many studies made use of some of the necessary measurements and controls, few used them all. The UVE is discussed in relation to this result and research methodology more broadly

Actors, Avatars and Agents: Potentials and Implications of Natural Face Technology for the Creation of Realistic Visual Presence

We are on the cusp of creating realistic, interactive, fully rendered human faces on computers that transcend the “uncanny valley,” widely known for capturing the phenomenon of “eeriness” in faces that are almost, but not fully realistic. Because humans are hardwired to respond to faces in uniquely positive ways, artificial realistic faces hold great promise for advancing human interaction with machines. For example, realistic avatars will enable presentation of human actors in virtual collaboration settings with new levels of realism; artificial natural faces will allow the embodiment of cognitive agents, such as Amazon’s Alexa or Apple’s Siri, putting us on a path to create “artificial human” entities in the near future. In this conceptual paper, we introduce natural face technology (NFT) and its potential for creating realistic visual presence (RVP), a sensation of presence in interaction with a digital actor, as if present with another human. We contribute a forward-looking research agenda to information systems (IS) research, comprising terminology, early conceptual work, concrete ideas for research projects, and a broad range of research questions for engaging with this emerging, transformative technology as it becomes available for application. By doing so, we respond to calls for “blue ocean research” that explores unchartered territory and makes a novel technology accessible to IS early in its application. We outline promising areas of application and foreshadow philosophical, ethical, and conceptual questions for IS research pertaining to the more speculative phenomena of “living with artificial humans.

The Uncanny Valley Effect

The Uncanny Valley Effect (UVE) first emerged as a warning against making industrial robots appear so highly human-like that they could unsettle the real humans around them. It proposed a specific pattern of negative emotional responses to entities that were almost but not quite human, and has been proposed as the reason why some entities such as dolls, mannequins and zombies may appear unsettling. The aim of this thesis was to move beyond an anecdotal explanation to understand more about the perception of near-human faces, and how this compares to the perception of human and non-human faces. The aims were to explore the relationship between the human-likeness of faces and emotional responses to them, to understand reactions to and descriptions of near-human faces, to explore aspects of how near-human faces are processed and to explore whether mismatched emotional expressions might contribute to the perception of some near-human faces as eerie. Five studies were carried out using face images whose human-likeness was systematically controlled or measured. A non-linear relationship between human-likeness and eeriness was found, but the near-human faces were not always the eeriest images. Near-human faces were found to be subject to the effects of inversion, and inversion was found to heighten perceptions of eeriness. Faces were created which contained mismatched emotional expressions, and the blends combining happy faces with angry or fearful eyes were rated as the most eerie. Incongruities between aspects of appearance or behaviour had been cited as explanations for the UVE in the past but this thesis presents the first evidence that differences in eeriness may result from incongruities between emotional expressions. Directions for future research have been suggested to explore these findings in a wider context and to understand more about the UVE

Design de animação no fundo do abismo: fotorrealismo e o uncanny valley

Certas abordagens do design de animação 3d procuram aproximar suas estéticas ao fotorrealismo. Essas tentativas correm o risco de causarem ao público alguns desconfortos ao revelarem a origem artificial dos personagens, fenômeno classificado como Uncanny Valley. Nesse contexto, o presente texto, configurado como pesquisa exploratória, tem o objetivo de analisar as possíveis causas de tais consequências a partir das obras do estúdio Image Movers Digital, que dedicou suas animações em longa-metragem predominantemente às imagens com semelhança visual fotográfica

Virtual animal characters in future communication : explorative study on character choice and agency

People need efficient means to communicate at a distance, but the available means to message can be inadequate. Any sent message might be perceived too little, fail to convey the intended emotion, or be received in a place, time or fashion that the sender would not prefer. There is room for new types of Computer-mediated communication. The thesis is an exploratory, mixed-methods study on a futuristic concept, where augmented-reality technology is used to send a lively and intelligent virtual animal character to enrich a message. The study goals are to find if the concept is acceptable, recognize common use cases for the messaging-characters, and to recognize if participants can identify different levels of independence to act, i.e. agency, for characters. To accomplish the goals, I conducted 12 interviews where I showed a low-fidelity prototype of the concept and designed animal character animations to the interviewees and had them first invent their own use scenarios and then select which characters they would use in predefined scenarios. To accomplish the agency goal, I had the interviewees order four animal animations by the level of independence to act shown by the animal. Overall, the results suggest the concept is acceptable. Augmented-reality animal messaging-characters could be used to enhance commonly send messages, and their strength is that they could be sent to act in a specific way to support the message. On types of interaction wished for, I found that most of the interviewees wished for more than animated statues, and many wished for the animals to act humanlike. However, they did not seem to wish for futuristic believable artificial intelligence. Concerning agency, the study brought into question the feasibility of defining a character’s level of agency. The results show that determining the level of agency shown in interacting animal character GIFs is either more difficult to do than I expected or outright impossible

Otakuism and the Appeal of Sex Robots

Social robots are becoming increasingly prevalent in everyday life and sex robots are a sub-category of especially high public interest and controversy. Starting from the concept of the otaku, a term from Japanese youth culture that describes secluded persons with a high affinity for fictional manga characters, we examine individual differences behind sex robot appeal (anime and manga fandom, interest in Japanese culture, preference for indoor activities, shyness). In an online-experiment, 261 participants read one out of three randomly assigned descriptions of future technologies (sex robot, nursing robot, genetically modified organism) and reported on their overall evaluation, eeriness, and contact/purchase intentions. Higher anime and manga fandom was associated with higher appeal for all three future technologies. For our male subsample, sex robots and GMOs stood out as shyness yielded a particularly strong relationship to contact/purchase intentions for these new technologies

Familiarity, orientation, and realism increase face uncanniness by sensitizing to facial distortions

The uncanny valley predicts aversive reactions toward near-humanlike entities. Greater uncanniness is elicited by distortions in realistic than unrealistic faces, possibly due to familiarity. Experiment 1 investigated how familiarity and inversion affect uncanniness of facial distortions and the ability to detect differences between the distorted variants of the same face (distortion sensitivity). Familiar or unfamiliar celebrity faces were incrementally distorted and presented either upright or inverted. Uncanniness ratings increased across the distortion levels, and were stronger for familiar and upright faces. Distortion sensitivity increased with increasing distortion difference levels, again stronger for familiar and upright faces. Experiment 2 investigated how face realism, familiarity, and face orientation interacted for the increase of uncanniness across distortions. Realism increased the increase of uncanniness across the distortion levels, further enhanced by upright orientation and familiarity. The findings show that familiarity, upright orientation, and high face realism increase the sensitivity of uncanniness, likely by increasing distortion sensitivity. Finally, a moderated linear function of face realism and deviation level could explain the uncanniness of stimuli better than a quadratic function. A re-interpretation of the uncanny valley as sensitivity toward deviations from familiarized patterns is discussed

A meta-analysis of the uncanny valley's independent and dependent variables

The uncanny valley (UV) effect is a negative affective reaction to human-looking artificial entities. It hinders comfortable, trust-based interactions with android robots and virtual characters. Despite extensive research, a consensus has not formed on its theoretical basis or methodologies. We conducted a meta-analysis to assess operationalizations of human likeness (independent variable) and the UV effect (dependent variable). Of 468 studies, 72 met the inclusion criteria. These studies employed 10 different stimulus creation techniques, 39 affect measures, and 14 indirect measures. Based on 247 effect sizes, a three-level meta-analysis model revealed the UV effect had a large effect size, Hedges’ g = 1.01 [0.80, 1.22]. A mixed-effects meta-regression model with creation technique as the moderator variable revealed face distortion produced the largest effect size, g = 1.46 [0.69, 2.24], followed by distinct entities, g = 1.20 [1.02, 1.38], realism render, g = 0.99 [0.62, 1.36], and morphing, g = 0.94 [0.64, 1.24]. Affective indices producing the largest effects were threatening, likable, aesthetics, familiarity, and eeriness, and indirect measures were dislike frequency, categorization reaction time, like frequency, avoidance, and viewing duration. This meta-analysis—the first on the UV effect—provides a methodological foundation and design principles for future research