D-Cycloserine (DCS) is a cognitive enhancing medication believed to “consolidate” fear extinction learning into memory during exposure therapy. This paper examines whether DCS could augment extinction of a specific fear in children. We conducted a double-blind placebo-controlled Randomized Controlled Trial to investigate whether 50mg of DCS can enhance fear extinction of a dog or spider phobia. Thus far, we have recruited 17 children (M age = 9.4 years) who ingested DCS or a placebo prior to receiving a massed session of in vivo exposure. Avoidance was measured using a standardized ten-step Behaviour Approach Tests (BAT), where successive steps increased proximity to the feared stimulus. BATs were conducted at pretreatment, immediately post-treatment and on follow-up one week later to measure return of fear.
Preliminary data indicates 94% of parents reported improvement in their child’s phobia symptoms after exposure therapy. This improvement is reflected in the significant increase in BAT steps completed from pre -treatment (M = 4.18/10 steps) to post–treatment (M = 8.94/10; t(16) = 6.92, p < .01), however, there was return of fear from post -treatment to follow-up (M = 6.88/10; t(16) = 3.60, p < .01) . Upon finalizing results, we will break the blinding to examine whether there is less return of fear among children who took DCS.
A single session of exposure was effective in reducing fear response for a childhood phobia; however, there was return of fear one week later. We hypothesize there will be less return of fear in children who ingested DCS.