Self Esteem
Conditions
Brief summary
The purpose of this study is to explore the effects of endogenous opioids on self-esteem and attentional bias toward social cues. This is achieved by administering the drug naltrexone, which temporarily decreases endogenous opioid activity.
Interventions
DRUGNaltrexone
opioid receptor antagonist
DRUGPlacebo
Sponsors
McGill University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* good physical health, * normal kidney and liver function results from within previous year
Exclusion criteria
* allergy to naltrexone * kidney or liver injury or disorder * bipolar, panic, or psychotic disorders * epilepsy * smoking more than 15 cigarettes per day * pregnancy * substance abuse * use of opioid analgesics, cocaine, recreational drugs (e.g., marijuana, LSD, ecstasy, etc.), or prescription medication (except oral contraceptives) within the past 10 days * use of over-the-counter drugs (e.g., analgesics, anti-inflammatories, sleeping aids, etc.) or alcohol within the past 24 hours * current experience of pain (e.g., headache) * use of anti-diarrheal medications in the 7 days prior to the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Self-esteem | Approximately 2 hours post placebo/drug administration | Self-reported levels of self-esteem assessed using the Rosenberg Self-Esteem Scale (Rosenberg, 1965). Possible scores range from 1 to 4. Higher scores indicate higher levels of self-esteem. |
| Attentional bias scores for positive social cues on visual probe task | Approximately 2 hours post placebo/drug administration | Attentional bias was assessed using a Visual Probe Task. The investigators used a version of the VPT (DeWall, Maner, & Rouby, 2009) designed to assess attentional bias to cues of social acceptance (i.e., smiles). The outcome measure was attentional bias scores, calculated by subtracting mean reaction time scores on valid trials from mean reaction time on invalid trials. Higher positive scores indicate greater attentional bias to accepting faces. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Attentional bias scores for negative social cues on visual probe task | Approximately 2 hours post placebo/drug administration | Attentional bias was assessed using a Visual Probe Task. The investigators used a version of the VPT (DeWall, Maner, & Rouby, 2009) designed to assess attentional bias to cues of social rejection (i.e., disapproving faces). The outcome measure was attentional bias scores, calculated by subtracting mean reaction time scores on valid trials from mean reaction time on invalid trials. Higher positive scores indicate greater attentional bias to disapproving faces. |
| Reaction times on neutral-neutral trials on visual probe task | Approximately 2 hours post placebo/drug administration | Reaction times on neutral-neutral trials on the visual probe task were used to assess potential psychomotor side-effects of naltrexone |
| Self-liking | Approximately 2 hours post placebo/drug administration | For exploratory purposes, the self-esteem measure (Rosenberg, 1965) was split into two separate subscales examining feelings of self-liking and self-competence as in Tafarodi & Milne, 2002. Self-liking is thought to be more relationally derived and based on internalized perceptions of social approval. Scores range from 1 to 4, with higher scores indicating higher levels of self-liking. |
| Self-competence | Approximately 2 hours post placebo/drug administration | For exploratory purposes, the self-esteem measure (Rosenberg, 1965) was split into two separate subscales examining feelings of self-liking and self-competence as in Tafarodi & Milne, 2002. Self-competence is thought to be more autonomously derived and based on past goal pursuit. Scores range from 1 to 4, with higher scores indicating higher levels of self-competence. |
Outcome results
None listed