Preattentive processing of feared stimuli in blood–injection–injury fearful subjects ☆ Juan P. Sánchez-Navarro a, ⁎, José M. Martínez-Selva a , Ginesa Torrente a , Sara Pineda b , Jose B. Murcia-Liarte a , Eduvigis Carrillo-Verdejo a a University of Murcia, Spain b Hospital General Universitario Morales Meseguer, Murcia, Spain abstract article info Article history: Received 5 July 2011 Received in revised form 12 January 2012 Accepted 13 January 2012 Available online 31 January 2012 Keywords: Blood–injection–injury fear Preattentive processing Cardiac defence response Heart rate Skin conductance response Corrugator supercilii This research aimed to study the defence responses of blood–injection–injury (BII) fearful subjects elicited by the preattentive processing of their feared objects and by an abrupt acoustic stimulus. We selected 21 BII fearful subjects and 25 non-fearful controls from an initial sample of 128 women, according to their scores on the Fear Survey Scale (damage subscale) and the Mutilation Questionnaire. Subjects were exposed to a burst of white noise to promote a defence response, and to 48 pictures, depicting mutilations, as well as other affective contents, displayed through a backward masking procedure. Heart rate (HR), skin conduc- tance response (SCR) and corrugator supercilii activity were continuously recorded throughout the task. Both groups showed similar SCRs, EMG activity and cardiac defence responses to the acoustic stimulus, though fearful subjects showed greater initial HR deceleration than controls. While BII fearful subjects dis- played the usual defence response when exposed to a non-feared threatening stimulus, the preattentive pro- cessing of the pictures did not reveal autonomic differences between fearful subjects and controls. Mutilation pictures, however, evoked the greatest EMG activity, but only in the fearful group. These data further extend previous research on conscious perception of blood-related stimuli in BII fearful subjects, by showing a failure to recruit autonomic defence responses when blood-related pictures appear outside of conscious awareness. © 2012 Elsevier B.V. All rights reserved. 1. Introduction Subjects exposed to relevant fear stimuli usually respond with en- hanced psychophysiological reactivity that is stronger when fearful subjects are exposed to their feared object (e.g., Globisch et al., 1999; Wendt et al., 2008). This reaction usually includes skin conduc- tance response (SCR) and blood pressure increases, heart rate (HR) acceleration, or startle reflex enhancement, and appears even when the feared stimuli are presented outside awareness (Öhman and Soares, 1993). However, the study of blood–injection–injury (BII) phobic subjects has failed to find a consistent pattern of physiological responses to their feared objects. In contrast to other specific phobias (e.g., spiders or snakes), several studies have found an initial heart rate acceleration in BII phobics to the first presentations of pictures depicting mutilations, which attenuated and changed to deceleration in subsequent presentations of pictures (e.g., Klorman et al., 1977). In this line, Hamm et al. (1997) did not find enhanced autonomic reactivity, i.e., HR acceleration and greater SCRs when BII phobic sub- jects viewed pictures related to their phobia. Classically, the cardiac response of BII phobics when confronted with their feared object had been defined as a diphasic reaction char- acterized by an initial phase related to HR and blood pressure in- creases, immediately followed by a second phase characterized by bradycardia and low blood pressure that, in some instances, might give rise to fainting (Graham et al., 1961). The first phase was consid- ered as being related to sympathetic activity, while the second was proposed as being under parasympathetic control (Graham et al., 1961; Sarlo et al., 2002). However, contrasting data have been found in the studies conducted on BII phobics. For example, while some re- searchers have found HR deceleration when BII phobics are exposed to blood-related stimuli, like pictures (e.g., Hamm et al., 1997), other authors, using longer exposures, like surgery film-clips, have found an initial HR acceleration (during the first 66 seconds of exposure) fol- lowed by a diminution of the HR, that falls under baseline (i.e., decel- eration) at the end of the exposure, (e.g., Sarlo et al., 2002). Other studies have only found HR acceleration when BII subjects are exposed to blood-related film-clips, but accompanied by a marked fall in sys- tolic blood pressure (Sarlo et al., 2008). As proposed by these authors, the dysfunctional cardiovascular reaction observed in BII phobics would depend more on the involvement of the sympathetic system, rather than the parasympathetic system. Taken together, BII phobics show, overall, a diminished readiness for active defence when they International Journal of Psychophysiology 84 (2012) 95–101 ☆ This research was supported by a grant from the Seneca Foundation-Murcia Regional Agency for Science and Technology, 08839/PHCS/08. ⁎ Corresponding author at: Department of Human Anatomy and Psychobiology, School of Psychology, University of Murcia, 30100 Murcia, Spain. Tel.: + 34 868 887 707; fax: +34 868 884 111. E-mail address: jpedro@um.es (J.P. Sánchez-Navarro). 0167-8760/$ – see front matter © 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.ijpsycho.2012.01.016 Contents lists available at SciVerse ScienceDirect International Journal of Psychophysiology journal homepage: www.elsevier.com/locate/ijpsycho