Probing the influence of unconscious fear-conditioned visual stimuli on eye movements.
Efficient threat detection from the environment is critical for survival. Accordingly, fear-conditioned stimuli receive prioritized processing and capture overt and covert attention. However, it is unknown whether eye movements are influenced by unconscious fear-conditioned stimuli. We performed a classical fear-conditioning procedure and subsequently recorded participants' eye movements while they were exposed to fear-conditioned stimuli that were rendered invisible using interocular suppression. Chance-level performance in a forced-choice-task demonstrated unawareness of the stimuli. Differential skin conductance responses and a change in participants' fearfulness ratings of the stimuli indicated the effectiveness of conditioning. However, eye movements were not biased towards the fear-conditioned stimulus. Preliminary evidence suggests a relation between the strength of conditioning and the saccadic bias to the fear-conditioned stimulus. Our findings provide no strong evidence for a saccadic bias towards unconscious fear-conditioned stimuli but tentative evidence suggests that such an effect may depend on the strength of the conditioned response.
Visual Perception Laboratory, Department of Psychiatry, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; International Graduate Program Medical Neurosciences, Charité - Universitätsmedizin Berlin, Luisenstr. 56, 10117 Berlin, Germany. Electronic address: apoorva-rajiv.madipakkam@charite.de.
Apoorva Rajiv
AR
Madipakkam
Visual Perception Laboratory, Department of Psychiatry, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
Marcus
M
Rothkirch
Visual Perception Laboratory, Department of Psychiatry, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
Gregor
G
Wilbertz
Visual Perception Laboratory, Department of Psychiatry, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Bernstein Center for Computational Neuroscience, Philippstr. 13, 10115 Berlin, Germany.
Philipp
P
Sterzer
D000328:Adult; D001364:Awareness / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology*; D005133:Eye Movements / Q000502:physiology*; D000066499:Facial Recognition / Q000502:physiology*; D005239:Fear / Q000502:physiology*; D005260:Female; D005712:Galvanic Skin Response / Q000502:physiology*; D006801:Humans; D008297:Male; D014473:Unconscious, Psychology
Continuous flash suppression; Face perception; Fear conditioning; Saccades; Skin conductance responses; Unconscious processing