Effects of THC on Emotional Memory Retrieval

The Effects of Δ⁹-Tetrahydrocannabinol on the Retrieval of Emotional Memories

The main purpose of this study was to examine the effects of THC on the retrieval of emotional and neutral memories in healthy young adults. Secondary experiments included the effects of THC on the encoding of object and scene stimuli and a novel working memory task.

Here, the investigators aimed to investigate the effects of THC (15 mg) on the retrieval of negative, neutral, and positive memories. The study used a placebo-controlled, within-subjects, crossover design with 24 participants. In each experimental arm, participants attend a session to encode stimuli, a second session 48 hours later in which their memories are tested for the stimuli from the first session followed by the encoding of object-scene stimuli and a working memory test, and a third session 48 hours later in which memory for the object-scene stimuli is tested. In the second session, two hours prior to memory testing, THC or placebo is administered. On the first and second sessions subjects complete mood questionnaires.

Inclusion Criteria:

• 4-100 lifetime cannabis occasions

Exclusion Criteria:

• Current Axis I DSM-IV disorder, including substance dependence, current use of >5 cigarettes per day, history of psychosis or mania, less than a high school education, lack of English fluency, a body mass index outside 19-33 kg/m2, high blood pressure (>140/90), abnormal electrocardiogram, daily use of any medication other than birth control, pregnancy, or lactating.