Neural foundations of threat processing in phobic subjects

Ancestral stimuli like snakes, spiders or rodents represent the core group of stimuli that humans are most frequently afraid of (Agras, Sylvester, & Oliveau, 1969; Marks, 1969). Phobic responses to these stimuli are almost equally prevalent among different populations (9–14%) with a significant dominance among females. Whether this prevalence and dominance is based on phylogenetic preparedness (Öhman, Esteves, & Soares, 1995; Seligman, 1971) or on other evolutionary-based information processing systems of the brain (LeDoux, 1996), or whether it is the result of acquired cognitive schemata (Beck & Emery, 1985) or specialized memory functions (Bower, 1981; Lang, Davis, & Öhman, 2000; Williams, Watts, MacLeod, & Mathews, 1997) is still a matter of debate. However, there is general agreement that the presence of these stimuli automatically captures subjects’ attention. Simultaneously, subjects’ arousal increases significantly and behavioral flight/fight responses and emotional feelings of threat are generated (Lang et al., 2000; Marks & Lader, 1973; Williams et al., 1997).