In This Issue

A single dose of d-cycloserine or alprazolam before each session of virtual reality therapy did not increase overall symptom improvement more than adjunctive placebo in 156 veterans with combat-related posttraumatic stress disorder (PTSD). The alprazolam group actually had higher symptom ratings at the end of treatment and a higher rate of PTSD diagnosis at 3-month follow-up, compared to the placebo group. Rothbaum et al. (p. 640) did observe two advantages for d-cycloserine: greater decreases in salivary cortisol and startle response and an association between extinction learning and symptom improvement. Explanations proposed by editorialist Neylan (p. 597) for the mixed findings include the possibility that d-cycloserine’s effects are not strong enough or that therapeutic improvement depends on more than extinction learning.