Brief Mental Training and Internal Attentional Control in Repetitive Negative Thinking: Experimental Laboratory Investigation

Participants will complete all assessments and training in a single laboratory session. Participants (N=105) with elevated levels of negative repetitive thinking (Rumination Response Scale -Brooding >=11) will be randomly assigned to one of 3 intervention arms: Attention Feedback Awareness and Control Training (A-FACT; n=35), Mindful Disengagement from Thoughts Training (MDTT; n=35), or placebo control (n=35).

At pre- and post-intervention, the investigators will measure: (1) Subjective emotional reactivity in response to negative vs. neutral self-referential thoughts using the Simulated Thought Paradigm (STP)-Emotional Reactivity task; (2) Interoceptive attention (i.e. sensibility) of the subjective location, intensity and hedonic tone of bodily sensations, using the STP-Body Map task, and (3) internal attentional control (i.e. latency to disengage) using the STP-Digit Categorization Task.

At post-intervention assessment only, the investigators will measure: (1) Meta-awareness of internal attentional dyscontrol using the STP-Digit Categorization Task with Self-Caught Probes; (2) internal attentional control (i.e. selective attention) using the STP-One-Back Dichotic Listening Task as a measure of the generalizability of the expected primary effect on internal attentional control.

The primary aim is to test the effect of 2 active intervention arms, Attention Feedback Awareness and Control Training and Mindful Disengagement from Thoughts Training, relative to one another and placebo control, on internal attentional control from pre-to-post training among adults with elevated negative repetitive thinking. The investigators hypothesise that both active interventions conditions will yield improvement in internal attentional control, as measured by the Digit Categorization Task integrated with the Simulated Thoughts Paradigm, from pre-to-post intervention, relative to the placebo-control.

Secondary aims are to test the effects of the 2 active intervention arms, relative to one another and placebo control, on subjective emotional reactivity to negative self-referential thoughts, selection bias to negative self-referential thoughts, meta-awareness of attentional dyscontrol, as well as interoceptive attention to bodily sensations in response to negative self-referential thoughts. The investigators hypothesize that, relative to the control-placebo group, the active intervention groups will yield (a) reduced emotional reactivity to negative self-referential thoughts as measured in the Emotional Reactivity Task, (b) higher levels of meta-awareness of attentional dyscontrol as measured by the STP-Digit Categorization Task with Self-Caught Probes, and (c) higher levels of selective internal attentional control as measured by the STP-One-Back Dichotic Listening Task.