A feasibility study. Can self positive implicit cognitive biases be trained to improve mood?

Self-related information receives prioritised processing, this is termed self-bias. Self-bias is observed in attention, memory, perception and decision-making. For example, in the shape-label matching tasks, when participants are told to associate shapes with different people, they will be fastest and most accurate at judging whether a presented pairing match one previously learnt when the pairing relates to themselves (Sui et al., 2012). The self-bias is usually considered extremely stable; however, mood disorders influence it. Negative mood induction leads to reduced self-biases (Sui et al., 2016). Further research has been conducted in naturally depressed individuals, but no change has been observed in self-bias. However, extension of the shape-label matching task to include emotional faces has found emotional insensitivity in depressed populations (McIvor et al., 2020). This contrasts the self-negativity bias usually predicted by mood disorder theories. This contradiction may stem from the differences in explicit and implicit expressions of depression. However, in pilot work using pre-clinically depressed individuals a negative self-bias is found. Traditional interventions such as cognitive behavioural therapy (CBT) have widely been used to reduce the negative biases in depression through conscious thought changes (Ward et al., 2000). CBT leads to a reduction in depression symptom severity and has interestingly been found to also reduce negative attentional biases indicating that attentional biases could be considered as clinical markers of depression and suggests a potential for targets of interventions (Segal & Gemar, 1997; Vazquez et al., 2018). Cognitive bias manipulation (CBM) to induce negative cognitive biases results in increased anxiety and depression. Previous studies using CBM to reduce depression have focused primarily on attention training to reduce focus to threatening stimuli and interpretation training to reduce the negative interpretation of ambiguous events. The results from these studies have been mixed and a meta-analysis finds that CBM has a medium effect on cognitive biases but only a small effect on symptoms (Hallion & Ruscio, 2011). This may be due to CBM targeting generalised negative biases (to attention or events) rather than specific self-negative biases. The aim of this feasibility study is to explore whether training self valenced implicit cognitive biases can increase self-positive biases, and/or reduce self-negative biases and therefore improve mood and reduce depressive symptoms.