Ever since ?hman, Flykt and Esteves published their classic study in 2001, many researchers have replicated their findings regarding attentional bias to threatening stimuli in visual perception research. Based on these findings, psychologists proposed a promising theory called predatory fear, in which the attentional bias to threatening animals is interpreted as evolutionarily adaptive behavior of early mammals and the ancestors of modern humans. However, from an evolutionary perspective, the lack of ecological validity of existing experiments inevitably attenuated the interpretation. The present study aimed to fill the gaps by repeating the classic work in a virtual reality environment.
A virtual reality grove was created with the Virtools virtual reality engine, in which jungles, trees, flowers, and weeds were arranged in the form of a wild grass field. The virtual reality grove was presented with an Oculus Rift DK 2 helmet. Forty participants were instructed to navigate along a path in the grove and search for threatening or non-threatening target stimuli. 3D models of a snake, a spider, a flower, a mushroom, a cicada, and a squirrel were used as stimuli in the search task, among which snake and spider were considered threatening stimuli. All the stimuli were shown in yellow and were assessed by twenty participants not included in the forty participants in search task to ensure they were of similar salience.
To examine attentional bias to threatening stimuli, two experiments were conducted in the same visual search task as reported by ?hman et al. In Experiment 1, as in ?hman et al., the snake or the spider was selected as a target stimulus, and thirteen copies of the flower or the mushroom were used as distracting stimuli, or other combinations of these. Twenty participants were individually presented with the virtual grove and instructed to passively wander along the path in the jungle to search for target stimuli. A fixed camera was set at a uniform speed to simulate the navigation in visual search task. Given that searching for animals took less time than searching for plants ( Soares et al, 2009), flowers and mushrooms were replaced with cicadas and squirrels in Experiment 2. The other twenty participants repeated the experiment procedure. In addition to response time (RT), response distance (RD) was also computed as a compensatory index.
In Experiment 1, the results of RTs revealed that the searching for threatening stimuli (snake and spider) is faster than searching for non-threatening stimuli (mushroom, flower). The RD values showed that participants found the threatening stimuli when they were farther away than the non-threatening stimuli. In Experiment 2, the same results were found even when the distracting stimuli were all animals. The RTs and RDs both confirmed that participants were better at finding snakes and spiders than finding flowers, mushrooms, cicadas, and squirrels.
The total results supported the hypothesis of predatory fear was relatively soundly and the attentional bias to threatening animals, especially snake and spider, was found to be likely to be caused by predatory fear as part of human cognition. These findings provide new evidence for the hypothesis of predatory fear from an evolutionary perspective. In addition, virtual reality was proven to be a suitable technique for assessing the ecological validity of psychological experiments.
Buss, D. M . ( 1999). Evolutionary psychology: The new science of the mind. Boston: Allyn and Bacon.
Cisler J. M., Bacon A. K., & Williams N. L . ( 2009). Phenomenological characteristics of attentional biases towards threat: A critical review. Cognitive Therapy & Research, 33(2), 221-234.
Cisler J. M., & Koster E. H. W . ( 2010). Mechanisms of attentional biases towards threat in anxiety disorders: An integrative review. Clinical Psychology Review, 30(2), 203-216.
Dudeney J., Sharpe L., & Hunt C . ( 2015). Attentional bias towards threatening stimuli in children with anxiety: A meta-analysis. Clinical Psychology Review, 40, 66-75.
Felnhofer A., Kothgassner O. D., Schmidt M., Heinzle A. K., Beutl L., Hlavacs H., & Kryspin-Exner I . ( 2015). Is virtual reality emotionally arousing? Investigating five emotion inducing virtual park scenarios. International Journal of Human-Computer Studies, 82, 48-56.
Gibson, J. J . ( 1979). The ecological approach to visual perception. Boston, MA: Houghton Mifflin.
Hansen C. H., & Hansen R. D . ( 1988). Finding the face in the crowd: An anger superiority effect. Journal of Personality & Social Psychology, 54(6), 917-924.
Itti L., & Koch C . ( 2000). A saliency-based search mechanism for overt and covert shifts of visual attention. Vision Research, 40(10-12), 1489-1506.
Janczyk M., Augst S., & Kunde W . ( 2014). The locus of the emotional Stroop effect: A study with the PRP paradigm. Acta Psychologica, 151, 8-15.
Juth P., Lundqvist D., Karlsson A., & ?hman A . ( 2005). Looking for foes and friends: Perceptual and emotional factors when finding a face in the crowd. Emotion, 5(4), 379-395.
Ledoux, J. E . ( 2000). Emotion circuits in the brain. Annual Review of Neuroscience, 23, 155-184.
Lee D. N., & Kalmus H . ( 1980). The optic flow field: The foundation of vision [and discussion]. Philosophical Transactions of the Royal Society B: Biological Sciences, 290(1038), 169-179.
Lindsay P. H. , & Norman, D. A.( 1977) .Human information processing: An introduction to psychology New York: Academic Press An introduction to psychology. New York: Academic Press.
LoBue, V. ( 2010). And along came a spider: An attentional bias for the detection of spiders in young children and adults. Journal of Experimental Child Psychology, 107(1), 59-66.
LoBue V., & Rakison D. H . ( 2013). What we fear most: A developmental advantage for threat-relevant stimuli. Developmental Review, 33(4), 285-303.
Matsumoto, E. ( 2010). Bias in attending to emotional facial expressions: Anxiety and visual search efficiency. Applied Cognitive Psychology, 24(3), 414-424.
Mogg K., & Bradley B. P . ( 2006). Time course of attentional bias for fear-relevant pictures in spider-fearful individuals. Behaviour Research & Therapy, 44(9), 1241-1250.
Mogg K., Bradley B. P., & Hallowell N . ( 1994). Attentional bias to threat: Roles of trait anxiety, stressful events, and awareness. The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology, 47(4), 841-864.
?hman, A. ( 2009). Of snakes and faces: An evolutionary perspective on the psychology of fear. Scandinavian Journal of Psychology, 50(6), 543-552.?hman, A., Flykt, A., & Esteves, F. (2001). Emotion drives attention: Detecting the snake in the grass. Journal of Experimental Psychology: General, 130(3), 466-478.
?hman A., Lundqvist D., & Esteves F . ( 2001). The face in the crowd revisited: A threat advantage with schematic stimuli. Journal of Personality & Social Psychology, 80(3), 381-396.
?hman A., & Mineka S . ( 2001). Fears, phobias, and preparedness: Toward an evolved module of fear and fear learning. Psychological Review, 108, 483-522.
?hman A., Soares S. C., Juth P., Lindstr?m B., & Esteves F . ( 2012). Evolutionary derived modulations of attention to two common fear stimuli: Serpents and hostile humans. Journal of Cognitive Psychology, 24(1), 17-32.
Peira N., Golkar A., ?hman A., Anders S., & Wiens S . ( 2012). Emotional responses in spider fear are closely related to picture awareness. Cognition and Emotion, 26(2), 252-260.
Peng D. L. ( 2012). General psychology (4th ed.) . Beijing, China: Beijing Normal University Press.
[ 彭聃龄 . ( 2012). 普通心理学 (第4版). 北京: 北京师范大学出版社.]
Savage R. A., Lipp O. V., Craig B. M., Becker S. I., & Horstmann G . ( 2013). In search of the emotional face: Anger versus happiness superiority in visual search. Emotion, 13(4), 758-768.
Schubert T., Friedmann F., & Regenbrecht H . ( 2001). The experience of presence: Factor analytic insights. Presence, 10(3), 266-281.
Soares, S. C . ( 2012). The lurking snake in the grass: Interference of snake stimuli in visually taxing conditions. Evolutionary Psychology, 10(2), 187-197.
Soares S. C., Esteves F., Lundqvist D., & ?hman A . ( 2009). Some animal specific fears are more specific than others: Evidence from attention and emotion measures. Behaviour Research & Therapy, 47(12), 1032-1042.
Soares S. C., Lindstr?m B., Esteves F., & ?hman A . ( 2014). The hidden snake in the grass: Superior detection of snakes in challenging attentional conditions. PLoS One, 9(12), e114724.
Stormark K. M., & Hugdahl K . ( 1996). Peripheral cuing of covert spatial attention before and after emotional conditioning of the cue. International Journal of Neuroscience, 86(3-4), 225-240.
Stormark K. M., Nordby H., & Hugdahl K . ( 1995). Attentional shifts to emotionally charged cues: Behavioural and ERP data. Cognition & Emotion, 9(5), 507-523.
Sun H. J., Carey D. P., & Goodale M. A . ( 1992). A mammalian model of optic-flow utilization in the control of locomotion. Experimental Brain Research, 91(1), 171-175.
Theeuwes, J. ( 2010). Top-down and bottom-up control of visual selection. Acta Psychologica, 135(2), 77-99.
Thrasher C., & LoBue V . ( 2016). Do infants find snakes aversive? Infants' physiological responses to "fear-relevant" stimuli. Journal of Experimental Child Psychology, 142, 382-389.
Tooby J., & Cosmides L . ( 1990). The past explains the present: Emotional adaptations and the structure of ancestral environments. Ethology & Sociobiology, 11(4-5), 375-424.
Torralba A., Oliva A., Castelhano M. S., & Henderson J. M . ( 2006). Contextual guidance of eye movements and attention in real-world scenes: The role of global features in object search. Psychological Review, 113(4), 766-786.
Tsotsos J. K., Culhane S. M., Kei W. W. Y., Lai Y. Z., Davis N., & Nuflo F . ( 1995). Modeling visual attention via selective tuning. Artificial Intelligence, 78(1-2), 507-545.
Urech A., Krieger T., Chesham A., Mast F. W., & Berger T . ( 2015). Virtual reality-based attention bias modification training for social anxiety: A feasibility and proof of concept study. Frontiers in Psychiatry, 6, 154.
van Le Q., Isbell L. A., Matsumoto J., Nguyen M., Hori E., Maior R. S., … Nishijo H . ( 2013). Pulvinar neurons reveal neurobiological evidence of past selection for rapid detection of snakes. Proceedings of the National Academy of Sciences of the United States of America, 110(47), 19000-19005.
Vuilleumier P., Armony J. L., Driver J., & Dolan R. J . ( 2003). Distinct spatial frequency sensitivities for processing faces and emotional expressions. Nature Neuroscience, 6(6), 624-631.
Wang F. X., Li W. J., Yan Z. Q., Duan Z. H., & Li H . ( 2015). Children's attention detection to snakes: Evidence from eye movements. Acta Psychologica Sinica, 47(6), 774-786.
Yiend, J. ( 2010). The effects of emotion on attention: A review of attentional processing of emotional information. Cognition & Emotion, 24(1), 3-47.
Zhang Y., Luo Y., Zhao S. Y., Chen W., & Li H . ( 2014). Attentional bias towards threat: Facilitated attentional orienting or impaired attentional disengagement. Advances in Psychological Science, 22(7), 1129-1138.