Validation of the open biological negative image set for a Portuguese population: Comparing Japanese and Portuguese samples and an exploration of low-order visual properties of the stimuli.

Recently, Shirai and Watanabe Royal Society Open Science, 9(1), 211128 (2022) developed OBNIS (Open Biological Negative Image Set), a comprehensive database containing images (primarily animals but also fruits, mushrooms, and vegetables) that visually elicit disgust, fear, or neither. OBNIS was initially validated for a Japanese population. In this article, we validated the color version of OBNIS for a Portuguese population. In study 1, the methodology of the original article was used. This allowed direct comparisons between the Portuguese and Japanese populations. Aside from a few emotional classification mismatches between disgust, fear, or neither-related images, we found that arousal and valence relate distinctively in both populations. In contrast to the Japanese sample, the Portuguese reported increased arousal for more positive valenced stimuli, suggesting that OBNIS images elicit positive emotions in the Portuguese population. These results showed important cross-cultural differences regarding OBNIS. In study 2, a methodological change was introduced: instead of the three classification options used originally (fear, disgust, or neither), six basic emotions were used (fear, disgust, sadness, surprise, anger, happiness), and a "neither" option, to confirm whether some of the originally "neither-related" images are associated with positive emotions (happiness). Additionally, the low-order visual properties of images (luminosity, contrast, chromatic complexity, and spatial frequency distribution) were explored due to their important role in emotion-related research. A fourth image group associated with happiness was found in the Portuguese sample. Moreover, image groups present differences regarding the low-order visual characteristics, which are correlated with arousal and valence ratings, highlighting the importance of controlling such characteristics in emotion-related research.

Emotional self-body odors do not influence the access to visual awareness by emotional faces.

A growing body of research suggests that emotional chemosignals in others' body odor (BO), particularly those sampled during fearful states, enhance emotional face perception in conscious and preconscious stages. For instance, emotional faces access visual awareness faster when presented with others' fear BOs. However, the effect of these emotional signals in self-BO, that is, one's own BO, is still neglected in the literature. In the present work, we sought to determine whether emotional self-BOs modify the access to visual awareness of emotional faces. Thirty-eight women underwent a breaking-Continuous Flash Suppression task in which they were asked to detect fearful, happy, and neutral faces, as quickly and accurately as possible, while being exposed to their fear, happiness, and neutral self-BOs. Self-BOs were previously collected and later delivered via an olfactometer, using an event-related design. Results showed a main effect of emotional faces, with happy faces being detected significantly faster than fearful and neutral faces. However, our hypothesis that fear self-BOs would lead to faster emotional face detection was not confirmed, as no effect of emotional self-BOs was found-this was confirmed with Bayesian analysis. Although caution is warranted when interpreting these results, our findings suggest that emotional face perception is not modulated by emotional self-BOs, contrasting with the literature on others' BOs. Further research is needed to understand the role of self-BOs in visual processing and emotion perception.

Investigating Inattentional Blindness Through the Lens of Fear Chemosignals.

Inattentional blindness is a phenomenon wherein people fail to perceive obvious stimuli within their vision, sometimes leading to dramatic consequences. Research on the effects of fear chemosignals suggests that they facilitate receivers' sensory acquisition. We aimed to examine the interplay between these phenomena, investigating whether exposure to fear chemosignals (vs. rest body odors) can reduce the inattentional-blindness handicap. Utilizing a virtual-reality aquarium, we asked participants to count how many morsels a school of fish consumed while two unexpected stimuli swam by. We predicted that participants exposed to fear chemosignals (N = 131) would detect unexpected stimuli significantly more often than participants exposed to rest body odors (N = 125). All participants were adult Portuguese university students aged 18 to 40 years. The results confirmed our hypothesis, χ2(1) = 6.10, p = .014, revealing that exposure to fear chemosignals significantly increased the detection of unexpected stimuli by about 10%. The implications of our findings open a novel avenue for reducing the adverse consequences of inattentional blindness.

Comparing fear and anxiety chemosignals: Do they modulate facial muscle activity and facilitate identifying facial expressions?

Fear and anxiety are the most frequently studied emotional states in chemosignal research. Despite differences between these two emotional states, findings from research using fear and anxiety body odors (BOs) are often treated as part of a similar phenomenon. In this article, we examine possible similarities and differences between participants exposed to fear and anxiety BOs on 2 dependent variables commonly used in chemosignals' research: (1) the activation of facial muscles in displays of fear expressions (i.e. the medial frontalis and the corrugator supercilii); and (2) the time required to discriminate between negative emotional expressions (fear, anger, and disgust) and neutral ones. Our results show that fear (vs. rest) and anxiety (vs. exercise) BOs activate the medial frontalis, suggesting that both have a similar impact on receivers' facial muscles. However, we could not replicate previous findings regarding the influence of fear BOs in discriminating negative emotional faces from neutral ones. Two additional replication attempts failed to replicate the earlier results, indicating that the results reported in the literature with this specific paradigm should be interpreted cautiously. Suggestions for future research examining possible differences between fear and anxiety BOs are advanced.

When are puppies receptive to emotion-induced human chemosignals? The cases of fear and happiness.

We report an observational, double-blind, experimental study that examines the effects of human emotional odors on puppies between 3 and 6 months and adult dogs (one year and upwards). Both groups were exposed to control, human fear, and happiness odors in a between subjects' design. The duration of all behaviors directed to the apparatus, the door, the owner, a stranger, and stress behaviors was recorded. A discriminant analysis showed that the fear odor activates consistent behavior patterns for both puppies and adult dogs. However, no behavioral differences between the control and happiness odor conditions were found in the case of puppies. In contrast, adult dogs reveal distinctive patterns for all three odor conditions. We argue that responses to human fear chemosignals systematically influence the behaviors displayed by puppies and adult dogs, which could be genetically prefigured. In contrast, the effects of happiness odors constitute cues that require learning during early socialization processes, which yield consistent patterns only in adulthood.

How priming with body odors affects decision speeds in consumer behavior.

To date, odor research has primarily focused on the behavioral effects of common odors on consumer perception and choices. We report a study that examines, for the first time, the effects of human body odor cues on consumer purchase behaviors. The influence of human chemosignals produced in three conditions, namely happiness, fear, a relaxed condition (rest), and a control condition (no odor), were examined on willingness to pay (WTP) judgments across various products. We focused on the speed with which participants reached such decisions. The central finding revealed that participants exposed to human odors reached decisions significantly faster than the no odor control group. The main driving force is that human body odors activate the presence of others during decision-making. This, in turn, affects response speed. The broader implications of this finding for consumer behavior are discussed.

A multi-analyses approach of inductive/deductive asymmetry in the affective priming paradigm.

Rapidly evaluating our environment's beneficial and detrimental features is critical for our successful functioning. A classic paradigm used to investigate such fast and automatic evaluations is the affective priming (AP) paradigm, where participants classify valenced target stimuli (e.g., words) as good or bad while ignoring the valenced primes (e.g., words). We investigate the differential impact that verbs and adjectives used as primes and targets have on the AP paradigm. Based on earlier work on the Linguistic Category Model, we expect AP effect to be modulated by non-evaluative properties of the word stimuli, such as the linguistic category (e.g., if the prime is an adjective and the target is a verb versus the reverse). A reduction in the magnitude of the priming effect was predicted for adjective-verb prime-target pairs compared to verb-adjective prime-target pairs. Moreover, we implemented a modified crowdsourcing of statistical analyses implementing independently three different statistical approaches. Deriving our conclusions on the converging/diverging evidence provided by the different approaches, we show a clear deductive/inductive asymmetry in AP paradigm (exp. 1), that this asymmetry does not require a focus on the evaluative dimension to emerge (exp. 2) and that the semantic-based asymmetry weakly extends to valence (exp. 3).

The spatial grounding of politics.

In three studies, we advance the research on the association between abstract concepts and spatial dimensions by examining the spatial anchoring of political categories in three different paradigms (spatial placement, memory, and classification) and using non-linguistic stimuli (i.e., photos of politicians). The general hypothesis that politicians of a conservative or socialist party are grounded spatially was confirmed across the studies. In Study 1, photos of politicians were spontaneously placed to the left or right of an unanchored horizontal line depending on their socialist-conservative party affiliation. In Study 2, the political orientation of members of parliament systematically distorted the recall of the spatial positions in which they were originally presented. Finally, Study 3 revealed that classification was more accurate and faster when the politicians were presented in spatially congruent positions (e.g., socialist politician presented on the left side of the monitor) rather than incongruent ones (e.g., socialist on the right side). Additionally, we examined whether participants' political orientation and awareness moderated these effects and showed that spatial anchoring seems independent of political preference but increases with political awareness.

Puppies in the problem-solving paradigm: quick males and social females.

We report an observational, double-blind study that examined puppies' behaviors while engaged in solving an experimental food retrieval task (food retrieval task instrument: FRTI). The experimental setting included passive social distractors (i.e., the dog's owner and a stranger). The focus was on how the social and physical environment shapes puppies' behaviors according to sex. The dependent variables were the number of tasks solved on an apparatus (Performance Index) and the time required to solve the first task (Speed). Sex and Stress were set as explanatory factors, and Social Interest, FRTI interactions, other behavior, and age as covariates. The main findings were that male puppies solved the first task faster than females. On the other hand, females displayed significantly more social interest and did so more rapidly than males. Males showed delayed task resolution. This study demonstrates sex differences in a problem-solving task in dog puppies for the first time, thus highlighting that sexually dimorphic behavioral differences in problem-solving strategies develop early on during ontogenesis.

Two Cultural Processing Asymmetries Drive Spatial Attention.

Cultural routines, such as reading and writing direction (script direction), channel attention orientation. Depending on one's native language habit, attention is biased from left-to-right (LR) or from right-to-left (RL). Here, we further document this bias, as it interacts with the spatial directionality that grounds time concepts. We used a spatial cueing task to test whether script direction and the grounding of time in Portuguese (LR, Exp. 1) and Arabic (RL, Exp. 2) shape visuomotor performance in target discrimination. Temporal words (e.g., tomorrow, yesterday) were presented as cues in two modalities: visual (Exp. 1-2) and auditory (Exp. 1). Gaze movement (Exp. 1) and speed of discrimination decisions (Exp. 1-2) of targets presented to the left or right sides of the screen were assessed. As predicted, the interaction between target location and time concepts was significant across both modalities and linguistic communities. Additionally, LR participants detected the target on the right side of the screen faster after a future word than the target on the left side of the screen after a past word cue. In contrast, RL participants detected the target on the left side of the screen faster when the cue word was a future word than the target on the right side of the screen cued by a past word. In both modalities, the initial eye-gaze movement (Exp. 1) was responsive to the cue's time referent, further confirming that time orients attention. An additional bias was observed for the first fixation onset, which landed earlier on the target set that matched habitualized spatial routines. We conclude that scanning regularities are shaped by writing habits and bodily grounded categorical features.

Can Humans Discriminate Horse 'Fear' Chemosignals from Control Chemosignals? Comment on Sabiniewicz et al. A Preliminary Investigation of Interspecific Chemosensory Communication of Emotions: Can Humans (Homo sapiens) Recognise Fear- and Non-Fear Body Odour from Horses (Equus ferus caballus). Animals 2021, 11, 3499.

We illustrate the problematic nature of different assumptions guiding the examination of whether humans can detect the source of fear chemosignals (i.e., body odors) emitted by horses-a research question examined in an article recently published in Animals. A central issue is that the formulation of the question itself contains the answer to it. In this paper, we parse the problematic assumptions on which the analysis and methodology rely, leading to conclusions that are difficult to support. These assumptions constitute examples of methodological problems that should be avoided in research with animals and odors. The unique aspect of this paper is that it is a collaborative product, including the original contributor, in the pursuit of transparency in science.

The Effect of Simultaneously Presented Words and Auditory Tones on Visuomotor Performance.

The experiment reported here used a variation of the spatial cueing task to examine the effects of unimodal and bimodal attention-orienting primes on target identification latencies and eye gaze movements. The primes were a nonspatial auditory tone and words known to drive attention consistent with the dominant writing and reading direction, as well as introducing a semantic, temporal bias (past-future) on the horizontal dimension. As expected, past-related (visual) word primes gave rise to shorter response latencies on the left hemifield and future-related words on the right. This congruency effect was differentiated by an asymmetric performance on the right space following future words and driven by the left-to-right trajectory of scanning habits that facilitated search times and eye gaze movements to lateralized targets. Auditory tone prime alone acted as an alarm signal, boosting visual search and reducing response latencies. Bimodal priming, i.e., temporal visual words paired with the auditory tone, impaired performance by delaying visual attention and response times relative to the unimodal visual word condition. We conclude that bimodal primes were no more effective in capturing participants' spatial attention than the unimodal auditory and visual primes. Their contribution to the literature on multisensory integration is discussed.

Facial emotion detection in Vestibular Schwannoma patients with and without facial paresis.

This study investigates whether there exist differences in facial emotion detection accuracy in patients suffering from Vestibular Schwannoma (VS) due to their facial paresis. Forty-four VS patients, half of them with, and half of them without a facial paresis, had to classify pictures of facial expressions as being emotional or non-emotional. The visual information of images was systematically manipulated by adding different levels of visual noise. The study had a mixed design with emotional expression (happy vs. angry) and visual noise level (10% to 80%) as repeated measures and facial paresis (present vs. absent) and degree of facial dysfunction as between subjects' factors. Emotion detection accuracy declined when visual information declined, an effect that was stronger for anger than for happy expressions. Overall, emotion detection accuracy for happy and angry faces did not differ between VS patients with or without a facial paresis, although exploratory analyses suggest that the ability to recognize emotions in angry facial expressions was slightly more impaired in patients with facial paresis. The findings are discussed in the context of the effects of facial paresis on emotion detection, and the role of facial mimicry, in particular, as an important mechanism for facial emotion processing and understanding.

The Function of Fear Chemosignals: Preparing for Danger.

It has been shown that the presence of conspecifics modulates human vigilance strategies as is the case with animal species. Mere presence has been found to reduce vigilance. However, animal research has also shown that chemosignals (e.g., sweat) produced during fear-inducing situations modulate individuals' threat detection strategies. In the case of humans, little is known about how exposure to conspecifics' fear chemosignals modulates vigilance and threat detection effectiveness. This study (N = 59) examined how human fear chemosignals affect vigilance strategies and threat avoidance in its receivers. We relied on a paradigm that simulates a "foraging under threat" situation in the lab, integrated with an eye-tracker to examine the attention allocation. Our results showed that the exposure to fear chemosignals (vs. rest chemosignals and a no-sweat condition) while not changing vigilance behavior leads to faster answers to threatening events. In conclusion, fear chemosignals seem to constitute an important warning signal for human beings, possibly leading their receiver to a readiness state that allows faster reactions to threat-related events.

Sex differences in the behavioral responses of dogs exposed to human chemosignals of fear and happiness.

This research focuses on sex differences in the behavioral patterns of dogs when they are exposed to human chemosignals (sweat) produced in happy and fear contexts. No age, breed or apparatus-directed behavior differences were found. However, when exposed to fear chemosignals, dogs' behavior towards their owners, and their stress signals lasted longer when compared to being exposed to happiness as well as control chemosignals. In the happy odor condition, females, in contrast to males, displayed a significantly higher interest to the stranger compared to their owner. In the fear condition, dogs spent more time with their owner compared to the stranger. Behaviors directed towards the door, indicative of exit interest, had a longer duration in the fear condition than the other two conditions. Female dogs revealed a significantly longer door-directed behavior in the fear condition compared to the control condition. Overall the data shows that the effect of exposure to human emotional chemosignals is not sex dependent for behaviors related to the apparatus, the owner or the stress behaviors; however, in the happiness condition, females showed a stronger tendency to interact with the stranger.

Perceiving emotions in visual stimuli: social verbal context facilitates emotion detection of words but not of faces.

Building on the notion that processing of emotional stimuli is sensitive to context, in two experimental tasks we explored whether the detection of emotion in emotional words (task 1) and facial expressions (task 2) is facilitated by social verbal context. Three different levels of contextual supporting information were compared, namely (1) no information, (2) the verbal expression of an emotionally matched word pronounced with a neutral intonation, and (3) the verbal expression of an emotionally matched word pronounced with emotionally matched intonation. We found that increasing levels of supporting contextual information enhanced emotion detection for words, but not for facial expressions. We also measured activity of the corrugator and zygomaticus muscle to assess facial simulation, as processing of emotional stimuli can be facilitated by facial simulation. While facial simulation emerged for facial expressions, the level of contextual supporting information did not qualify this effect. All in all, our findings suggest that adding emotional-relevant voice elements positively influence emotion detection.

Asymmetric practices of reading and writing shape visuospatial attention and discrimination.

Movement is generally conceived of as unfolding laterally in the writing direction that one is socialized into. In 'Western' languages, this is a left-to-right bias contributing to an imbalance in how attention is distributed across space. We propose that the rightward attentional bias exercises an additional unidirectional influence on discrimination performance thus shaping the congruency effect typically observed in Posner-inspired cueing tasks. In two studies, we test whether faces averted laterally serve as attention orienting cues and generate differences in both target discrimination latencies and gaze movements across left and right hemifields. Results systematically show that right-facing faces (i.e. aligned with the script direction) give rise to an advantage for cue-target pairs pertaining to the right (versus left) side of space. We report an asymmetry between congruent conditions in the form of right-sided facilitation for: (a) response time in discrimination decisions (experiment 1-2) and (b) eye-gaze movements, namely earlier onset to first fixation in the respective region of interest (experiment 2). Left and front facing cues generated virtually equal exploration patterns, confirming that the latter did not prime any directionality. These findings demonstrate that visuospatial attention and consequent discrimination are highly dependent on the asymmetric practices of reading and writing.

Social Inferences From Faces as a Function of the Left-to-Right Movement Continuum.

We examined whether reading and writing habits known to drive agency perception also shape the attribution of other agency-related traits, particularly for faces oriented congruently with script direction (i.e., left-to-right). Participants rated front-oriented, left-oriented and right-oriented faces on 14 dimensions. These ratings were first reduced to two dimensions, which were further confirmed with a new sample: power and social-warmth. Both dimensions were systematically affected by head orientation. Right-oriented faces generated a stronger endorsement of the power dimension (e.g., agency, dominance), and, to a lesser extent, of the social-warmth dimension, relative to the left and frontal-oriented faces. A further interaction between the head orientation of the faces and their gender revealed that front-facing females, relative to front-facing males, were attributed higher social-warmth scores, or communal traits (e.g., valence, warmth). These results carry implications for the representation of people in space particularly in marketing and political contexts. Face stimuli and respective norming data are available at www.osf.io/v5jpd.

Not All Emotions Are Equal: Fear Chemosignals Lower Awareness Thresholds Only for Fearful Faces.

Exposure to body odors (chemosignals) collected under different emotional states (i.e., emotional chemosignals) can modulate our visual system, biasing visual perception. Recent research has suggested that exposure to fear body odors, results in a generalized faster access to visual awareness of different emotional facial expressions (i.e., fear, happy, and neutral). In the present study, we aimed at replicating and extending these findings by exploring if these effects are limited to fear odor, by introducing a second negative body odor-that is, disgust. We compared the time that 3 different emotional facial expressions (i.e., fear, disgust, and neutral) took to reach visual awareness, during a breaking continuous flash suppression paradigm, across 3 body odor conditions (i.e., fear, disgust, and neutral). We found that fear body odors do not trigger an overall faster access to visual awareness, but instead sped-up access to awareness specifically for facial expressions of fear. Disgust odor, on the other hand, had no effects on awareness thresholds of facial expressions. These findings contrast with prior results, suggesting that the potential of fear body odors to induce visual processing adjustments is specific to fear cues. Furthermore, our results support a unique ability of fear body odors in inducing such visual processing changes, compared with other negative emotional chemosignals (i.e., disgust). These conclusions raise interesting questions as to how fear odor might interact with the visual processing stream, whilst simultaneously giving rise to future avenues of research.

Quality of life, social function, emotion, and facial paresis in Dutch vestibular schwannoma patients.

OBJECTIVES: The present study aimed to replicate the finding that vestibular schwannoma (VS) patients with facial paresis experience lower health related quality of life (QoL) than those without facial paresis in a Dutch sample, and to extend these findings by measuring VS patients' overall satisfaction with life, social function, and emotion. METHODS: Forty-seven VS patients, differing in degree of facial functioning, half of them with and half of them without a facial paresis, answered questionnaires about health related QoL (SF-36 and PANQOL), overall satisfaction with life, fear of being evaluated negatively by others, social avoidance and distress, and characteristics and symptoms of depression. RESULTS: We observed that VS patients with facial paresis experience lower health-related QoL as well negatively impacted social function and emotion compared to VS patients without facial paresis. VS patients with facial paresis experienced lower overall satisfaction with life, more characteristic symptoms of depression, and more fear of being evaluated negatively by others than VS patients without facial paresis. CONCLUSION: These findings corroborate previous research showing an association between impaired facial functioning and lower QoL, but also extend them by showing differences on the quality of social function and emotion. Being aware of this difference between VS patients with and without facial paresis informs health practitioners regarding the specific support these patients might need. Moreover, it is also relevant to consider the influence of a facial paresis on patients' life when deciding between treatment options and in case of surgery the type of resection. LEVEL OF EVIDENCE: 3.