Acute anxiety and social inference: An experimental manipulation with 7.5% carbon dioxide inhalation

作者：Button Katherine S^*; Karwatowska Lucy; Kounali Daphne; Munafo Marcus R; Attwood Angela S

来源：Journal of Psychopharmacology, 2016, 30(10): 1036-1046.

DOI：10.1177/0269881116653105

• Anxiety
• carbon dioxide inhalation
• carbon dioxide levels
• learning
• negativity
• positivity
• self-perception
• self-referential processing
• social anxiety
• social judgement
• state anxiety
• trait anxiety

Background: Positive self-bias is thought to be protective for mental health. We previously found that the degree of positive bias when learning self-referential social evaluation decreases with increasing social anxiety. It is unclear whether this reduction is driven by differences in state or trait anxiety, as both are elevated in social anxiety; therefore, we examined the effects on the state of anxiety induced by the 7.5% carbon dioxide (CO2) inhalation model of generalised anxiety disorder (GAD) on social evaluation learning.
Methods: For our study, 48 (24 of female gender) healthy volunteers took two inhalations (medical air and 7.5% CO2, counterbalanced) whilst learning social rules (self-like, self-dislike, other-like and other-dislike) in an instrumental social evaluation learning task. We analysed the outcomes (number of positive responses and errors to criterion) using the random effects Poisson regression.
Results: Participants made fewer and more positive responses when breathing 7.5% CO2 in the other-like and other-dislike rules, respectively (gas x condition x rule interaction p = 0.03). Individuals made fewer errors learning self-like than self-dislike, and this positive self-bias was unaffected by CO2. Breathing 7.5% CO2 increased errors, but only in the other-referential rules (gas x condition x rule interaction p = 0.003).
Conclusions: Positive self-bias (i.e. fewer errors learning self-like than self-dislike) seemed robust to changes in state anxiety. In contrast, learning other-referential evaluation was impaired as state anxiety increased. This suggested that the previously observed variations in self-bias arise due to trait, rather than state, characteristics.

• 出版日期2016-10