Sensible
The Invisible Gorilla Strikes Again: Sustained Inattentional Blindness in Expert Observers
Trafton Drew, Melissa Võ & Jeremy Wolfe
Psychological Science, forthcoming
Abstract:
Researchers have shown that people often miss the occurrence of an unexpected yet salient event if they are engaged in a different task, a phenomenon known as inattentional blindness. However, demonstrations of inattentional blindness have typically involved naive observers engaged in an unfamiliar task. What about expert searchers who have spent years honing their ability to detect small abnormalities in specific types of images? We asked 24 radiologists to perform a familiar lung-nodule detection task. A gorilla, 48 times the size of the average nodule, was inserted in the last case that was presented. Eighty-three percent of the radiologists did not see the gorilla. Eye tracking revealed that the majority of those who missed the gorilla looked directly at its location. Thus, even expert searchers, operating in their domain of expertise, are vulnerable to inattentional blindness.
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Kristin Schneider, Roelie Hempel & Thomas Lynch
Emotion, forthcoming
Abstract:
Successful interpersonal functioning often requires both the ability to mask inner feelings and the ability to accurately recognize others' expressions - but what if effortful control of emotional expressions impacts the ability to accurately read others? In this study, we examined the influence of self-controlled expressive suppression and mimicry on facial affect sensitivity - the speed with which one can accurately identify gradually intensifying facial expressions of emotion. Muscle activity of the brow (corrugator, related to anger), upper lip (levator, related to disgust), and cheek (zygomaticus, related to happiness) were recorded using facial electromyography while participants randomized to one of three conditions (Suppress, Mimic, and No-Instruction) viewed a series of six distinct emotional expressions (happiness, sadness, fear, anger, surprise, and disgust) as they morphed from neutral to full expression. As hypothesized, individuals instructed to suppress their own facial expressions showed impairment in facial affect sensitivity. Conversely, mimicry of emotion expressions appeared to facilitate facial affect sensitivity. Results suggest that it is difficult for a person to be able to simultaneously mask inner feelings and accurately "read" the facial expressions of others, at least when these expressions are at low intensity. The combined behavioral and physiological data suggest that the strategies an individual selects to control his or her own expression of emotion have important implications for interpersonal functioning.
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Jasper de Groot, Gün Semin & Monique Smeets
Journal of Experimental Psychology: General, forthcoming
Abstract:
Recent evidence suggests that humans can become fearful after exposure to olfactory fear signals, yet these studies have reported the effects of fear chemosignals without examining emotion-relevant input from traditional communication modalities (i.e., vision, audition). The question that we pursued here was therefore: How significant is an olfactory fear signal in the broader context of audiovisual input that either confirms or contradicts olfactory information? To test this, we manipulated olfactory (fear, no fear) and audiovisual (fear, no fear) information and demonstrated that olfactory fear signals were as potent as audiovisual fear signals in eliciting a fearful facial expression. Irrespective of confirmatory or contradictory audiovisual information, olfactory fear signals produced by senders induced fear in receivers outside of conscious access. These findings run counter to traditional views that emotions are communicated exclusively via visual and linguistic channels.
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Disgust regulation via placebo: An fMRI study
Anne Schienle et al.
Social Cognitive and Affective Neuroscience, forthcoming
Abstract:
The present fMRI study investigated whether placebo treatment can change disgust feelings. Disgust-prone women underwent a retest design where they were presented with disgusting, fear-eliciting and neutral pictures once with and once without a placebo (inert pill presented with the suggestion that it can reduce disgust symptoms). The placebo provoked a strong decrease of experienced disgust, which was accompanied by reduced insula activation. Exploratory psychophysiological interaction analyses revealed decreased connectivity in a network consisting of the insula, the amygdala, the anterior cingulate cortex and the orbitofrontal cortex. Moreover, the placebo increased amygdala-DMPFC coactivation. Our findings suggest that placebo use can modulate a specific affective state and might be an option as a first therapy step for clinical samples characterized by excessive and difficult-to-control disgust feelings.
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Pride Displays Communicate Self-Interest and Support for Meritocracy
E.J. Horberg, Michael Kraus & Dacher Keltner
Journal of Personality and Social Psychology, July 2013, Pages 24-37
Abstract:
The present studies examined how observers infer moral attributes and beliefs from nonverbal pride displays. Pride is a self-focused positive emotion triggered by appraisals of the self's success, status, and competence. We hypothesized that when a target emits nonverbal cues of pride, he or she will be viewed by observers as higher in self-interest and therefore more likely to endorse ideologies that would benefit the self - specifically, merit-based resource distributions (meritocracy) as opposed to equality-based resource distributions (egalitarianism). Across studies, experimentally manipulated pride displays (Studies 1 and 3) and naturally occurring expressions of pride (Study 4) led observers to infer heightened support for meritocracy as opposed to egalitarianism. Analyses also revealed that people intuitively associate higher self-interest with enhanced support for meritocracy as opposed to egalitarianism (Study 2), and this association mediates the pathway from pride displays to inferences of heightened support for meritocracy and reduced support for egalitarianism (Studies 3 and 4). Across studies, we compare pride to expressions of joy or no emotion and demonstrate these effects using thin slices as well as static images.
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The gist of the abnormal: Above-chance medical decision making in the blink of an eye
Karla Evans et al.
Psychonomic Bulletin & Review, forthcoming
Abstract:
Very fast extraction of global structural and statistical regularities allows us to access the "gist" - the basic meaning - of real-world images in as little as 20 ms. Gist processing is central to efficient assessment and orienting in complex environments. This ability is probably based on our extensive experience with the regularities of the natural world. If that is so, would experts develop an ability to extract the gist from the artificial stimuli (e.g., medical images) with which they have extensive visual experience? Anecdotally, experts report some ability to categorize images as normal or abnormal before actually finding an abnormality. We tested the reality of this perception in two expert populations: radiologists and cytologists. Observers viewed brief (250- to 2,000-ms) presentations of medical images. The presence of abnormality was randomized across trials. The task was to rate the abnormality of an image on a 0-100 analog scale and then to attempt to localize that abnormality on a subsequent screen showing only the outline of the image. Both groups of experts had above-chance performance for detecting subtle abnormalities at all stimulus durations (cytologists d' ≈ 1.2 and radiologists d' ≈ 1), whereas the nonexpert control groups did not differ from chance (d' ≈ 0.23, d' ≈ 0.25). Furthermore, the experts' ability to localize these abnormalities was at chance levels, suggesting that categorization was based on a global signal, and not on fortuitous attention to a localized target. It is possible that this global signal could be exploited to improve clinical performance.
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Domna Banakou, Raphaela Groten & Mel Slater
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
An illusory sensation of ownership over a surrogate limb or whole body can be induced through specific forms of multisensory stimulation, such as synchronous visuotactile tapping on the hidden real and visible rubber hand in the rubber hand illusion. Such methods have been used to induce ownership over a manikin and a virtual body that substitute the real body, as seen from first-person perspective, through a head-mounted display. However, the perceptual and behavioral consequences of such transformed body ownership have hardly been explored. In Exp. 1, immersive virtual reality was used to embody 30 adults as a 4-y-old child (condition C), and as an adult body scaled to the same height as the child (condition A), experienced from the first-person perspective, and with virtual and real body movements synchronized. The result was a strong body-ownership illusion equally for C and A. Moreover there was an overestimation of the sizes of objects compared with a nonembodied baseline, which was significantly greater for C compared with A. An implicit association test showed that C resulted in significantly faster reaction times for the classification of self with child-like compared with adult-like attributes. Exp. 2 with an additional 16 participants extinguished the ownership illusion by using visuomotor asynchrony, with all else equal. The size-estimation and implicit association test differences between C and A were also extinguished. We conclude that there are perceptual and probably behavioral correlates of body-ownership illusions that occur as a function of the type of body in which embodiment occurs.
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Mirror Reading Can Reverse the Flow of Time
Daniel Casasanto & Roberto Bottini
Journal of Experimental Psychology: General, forthcoming
Abstract:
How does culture shape our concepts? Across many cultures, people conceptualize time as if it flows along a horizontal timeline, but the direction of this implicit timeline is culture specific: Later times are on the right in some cultures but on the left in others. Here we investigated whether experience reading can determine the direction and orientation of the mental timeline, independent of other cultural and linguistic factors. Dutch speakers performed space-time congruity tasks with the instructions and stimuli written in either standard, mirror-reversed, or rotated orthography. When participants judged temporal phrases written in standard orthography, their reaction times were consistent with a rightward-directed mental timeline, but after brief exposure to mirror-reversed orthography, their mental timelines were reversed. When standard orthography was rotated 90° clockwise (downward) or counterclockwise (upward), participants' mental timelines were rotated, accordingly. Reading can play a causal role in shaping people's implicit time representations. Exposure to a new orthography can change the direction and orientation of the mental timeline within minutes, even when the new space-time mapping directly contradicts the reader's usual mapping. To account for this representational flexibility, we propose the hierarchical mental metaphors theory, according to which culturally conditioned mappings between space and time are specific instances of a more general mapping, which is conditioned by the relationship between space and time in the physical world. Conceptualizations of time are culture specific at one level of analysis but may be universal at another.
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Francesca Ferri et al.
Proceedings of the Royal Society: Biological Sciences, 22 August 2013
Abstract:
More than 100 papers have been published on the rubber hand illusion since its discovery 14 years ago. The illusion has been proposed as a demonstration that the body is distinguished from other objects by its participation in specific forms of intermodal perceptual correlation. Here, we radically challenge this view by claiming that perceptual correlation is not necessary to produce the experience of this body as mine. Each of 15 participants was seated with his/her right arm resting upon a table just below another smaller table. Thus, the real hand was hidden from the participant's view and a life-sized rubber model of a right hand was placed on the small table in front of the participant. The participant observed the experimenter's hand while approaching - without touching - the rubber hand. Phenomenology of the illusion was measured by means of skin conductance response and questionnaire. Both measures indicated that participants experienced the illusion that the experimenter's hand was about to touch their hidden hand rather than the rubber hand, as if the latter replaced their own hand. This did not occur when the rubber hand was rotated by 180° or replaced by a piece of wood. This illusion indicates that our brain does not build a sense of self in a merely reactive way, via perceptual correlations; rather it generates predictions on what may or may not belong to itself.
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Evidence that the Lunar Cycle Influences Human Sleep
Christian Cajochen et al.
Current Biology, forthcoming
Abstract:
Endogenous rhythms of circalunar periodicity (∼29.5 days) and their underlying molecular and genetic basis have been demonstrated in a number of marine species. In contrast, there is a great deal of folklore but no consistent association of moon cycles with human physiology and behavior. Here we show that subjective and objective measures of sleep vary according to lunar phase and thus may reflect circalunar rhythmicity in humans. To exclude confounders such as increased light at night or the potential bias in perception regarding a lunar influence on sleep, we retrospectively analyzed sleep structure, electroencephalographic activity during non-rapid-eye-movement (NREM) sleep, and secretion of the hormones melatonin and cortisol found under stringently controlled laboratory conditions in a cross-sectional setting. At no point during and after the study were volunteers or investigators aware of the a posteriori analysis relative to lunar phase. We found that around full moon, electroencephalogram (EEG) delta activity during NREM sleep, an indicator of deep sleep, decreased by 30%, time to fall asleep increased by 5 min, and EEG-assessed total sleep duration was reduced by 20 min. These changes were associated with a decrease in subjective sleep quality and diminished endogenous melatonin levels. This is the first reliable evidence that a lunar rhythm can modulate sleep structure in humans when measured under the highly controlled conditions of a circadian laboratory study protocol without time cues.
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When body and mind are talking: Interoception moderates embodied cognition
Michael Häfner
Experimental Psychology, July/August 2013, Pages 255-259
Abstract:
Recent research on so-called embodied cognitions strengthens the current view that the body and the mind cannot be separated in producing cognitions. But how and when does the body talk to the mind? Drawing on the notion that bodily processes are transformed into mental action through experiences, it is argued that embodied cognitions should be moderated by interindividual differences in the sensitivity to stimuli originating inside of the body, that is, by interoception. In line with these assumptions, two experiments demonstrate that the embodiment of weight and softness in value judgments and person impressions is moderated by interoception as assessed by a body-awareness questionnaire (Experiment 1) and a heartbeat perception task (Experiment 2). Taken together, these findings strongly speak to the notion that bodily processes and the experience thereof play an important role in embodiment, thereby extending previous research above and beyond the mere demonstration of body-mind interactions.
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V.S. Chib et al.
Translational Psychiatry, June 2013
Abstract:
The midbrain lies deep within the brain and has an important role in reward, motivation, movement and the pathophysiology of various neuropsychiatric disorders such as Parkinson's disease, schizophrenia, depression and addiction. To date, the primary means of acting on this region has been with pharmacological interventions or implanted electrodes. Here we introduce a new noninvasive brain stimulation technique that exploits the highly interconnected nature of the midbrain and prefrontal cortex to stimulate deep brain regions. Using transcranial direct current stimulation (tDCS) of the prefrontal cortex, we were able to remotely activate the interconnected midbrain and cause increases in participants' appraisals of facial attractiveness. Participants with more enhanced prefrontal/midbrain connectivity following stimulation exhibited greater increases in attractiveness ratings. These results illustrate that noninvasive direct stimulation of prefrontal cortex can induce neural activity in the distally connected midbrain, which directly effects behavior. Furthermore, these results suggest that this tDCS protocol could provide a promising approach to modulate midbrain functions that are disrupted in neuropsychiatric disorders.