Abstract
Attention biases have been reported for ancestral threats like spiders and snakes in infants, children, and adults. However, it is currently unclear whether these stimuli induce increased physiological arousal in infants. Here, 6-month-old infants were presented with pictures of spiders and flowers (Study 1, within-subjects), or snakes and fish (Study 1, within-subjects; Study 2, between-subjects). Infants’ pupillary responses linked to activation of the noradrenergic system were measured. Infants reacted with increased pupillary dilation indicating arousal to spiders and snakes compared with flowers and fish. Results support the notion of an evolved preparedness for developing fear of these ancestral threats.
Highlights
Clinical fears of spiders and snakes have a prevalence rate of 1–5 percent (Fredrikson et al, 1996), a strong dislike of these animals is reported by more than a third of the child population (Muris et al, 1997) and the adult population (Davey, 1991), the latter from which even entomologists are not exempt (Vetter, 2013)
Results speak to increased arousal in response to spiders compared with flowers in 6-month-old infants
Six month old infants react with increased physiological arousal to these ancestral threats compared to non-threatening control stimuli
Summary
Clinical fears of spiders and snakes have a prevalence rate of 1–5 percent (Fredrikson et al, 1996), a strong dislike of these animals is reported by more than a third of the child population (Muris et al, 1997) and the adult population (Davey, 1991), the latter from which even entomologists are not exempt (Vetter, 2013). Fear of spiders and snakes are the most reported specific phobias, even though these animals hardly pose a threat to humans today (Russell, 1991; Fredrikson et al, 1996). Poulton and Menzies (2002) even suggested the existence of evolved fears of snakes and spiders that do not require fear-learning in ontogeny. These fears may, be extinguished through safe exposure and habituation in normal development explaining why specific phobias do not occur at an even higher prevalence rate. Evidence for arousal in response to snakes and spiders in early ontogeny would support the notion that an evolved mechanism underlies specific fears of ancestral threats in humans. We test whether young infants react with increased pupillary dilation to spiders and snakes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
