Fig 1.
Acquisition and extinction procedures.
Example of the CS/secondary-image and shock pairings presented during the acquisition stage of the experiment and CS alone presentations during the extinction stage of the experiment. During acquisition, participants viewed two sets of two neutral images (clocks, stools), and both images from each set were paired with the same secondary image (social support figure, stranger). One of these pairings from each set was paired with shock, the CS+/secondary-image pairing, and one pairing was never paired with shock, the CS-/secondary-image pairing. Following acquisition was an extinction stage, during which each neutral image was once again presented on its own (no secondary image and no shock). Conditional fear acquisition was measured by comparing SCR for the CS+/secondary-image pairing to the CS-/secondary-image pairing within each set of neutral images during the acquisition stage. The numbers in parentheses indicate number of CS/secondary-image or CS alone presentations. All presentations were 6s followed by a 10s ISI. The order for both stages was pseudo-randomized, and counterbalanced across participants.
Fig 2.
A). SCR from the Acquisition stage: conditional fear responses were evaluated by comparing the CS+/secondary-image to the CS-/secondary-image from each condition (social-support-paired, stranger-paired). A conditional fear response was acquired in the stranger-paired condition, but not in the social-support-paired condition. B). SCR from the first trial of the Extinction stage: conditional fear responses were evaluated by comparing the CS+ and CS- from each condition when once again presented alone (with the social support or stranger image removed). A marginal conditional fear response was still present for the CS+ that had been paired with a stranger image, but not for the CS+ that had been paired with a social-support-figure image. All error bars indicate standard error. Asterisks indicate a statistically significant difference score (** indicates p< or = .001, * indicates p < .05), “+” indicates a marginal difference score (p < .1), and “ns” indicates a non-significant difference.