Mind-wandering and dysphoria

Abstract

Mind-wandering shares a number of important similarities with thinking in depression. This experiment examines whether mind-wandering provides a useful marker of cognition in dysphoria during a word learning task. Dysphoria was associated with more accessible mind-wandering when attempting to encode verbal items. In addition, in the dysphoric population, periods when the mind wandered led to greater decoupling from task-relevant processing as indexed by slower response times, and greater physiological arousal, as indexed by faster heart rates. In the general population, periods of mind-wandering when attempting to encode information were associated with poor retrieval and high skin conductance. Finally, the extent to which mind-wandering was associated with poor retrieval was associated with an individuals’ latency to retrieve specific autobiographical memories from outside the laboratory. These results provide strong evidence for the utility of mind-wandering as a marker for depressive thinking and suggest a number of important implications for therapy for depression.

Acknowledgements

The data collection was partially funded by a grant from the Research and Development Fund at the University of Strathclyde. The writing of this paper was supported by a grant from the US Office of Education to Erik Reichle and Jonathan Schooler.

The authors wish to thank all the people who took part in this experiment and also the Scottish Depression Group, in particular Barbara Dritschel, for their encouragement and enthusiasm for the work presented in this article. Thanks to Joanne Elliot for her help in preparing the manuscript.

Notes

¹Mindfulness can be considered a state of mind in which the individual is “paying attention in a particular way: on purpose, in the present moment and non-judgementally” (Kabat-Zinn, 1994, p. 4). By contrast, the mindless processing of information, the conception/doing mode (Teasdale, 1999) is “dominated by relatively impersonal detached thoughts about the self or emotion (as objects) about goal orientated strategies … . Such thinking will often be related to the past or future rather than to immediate experience” (Teasdale, 1999, p. 68).

²In this experiment we were not concerned with the investigation of the consequences of the emotional quality of the stimuli to be studied.

³In this experiment we opted not to classify thinking in terms of the extent to which it was concerned with the appraisal of the self/task as in previous work (Smallwood et al., 2003a, 2003b). There were two reasons for this. First, previous research has implicated task unrelated thinking, but not task appraisal in the experience of dysphoria (Smallwood et al., 2003a, 2003b). Second, a detailed examination of both verbal reports and retrospective questionnaire data suggests that only the experience of task-unrelated thinking makes a measurable contribution to concurrent encoding (Smallwood et al., 2003a, 2003b).

⁴It is worth noting that research using the CES-D has suggested that scores of 40 or above on the CES-D are indicative of subsequent clinical depression (Field, Diago, & Sanders, 2001).

Of the 37 individuals, 1 individual reported no examples of mind-wandering during either task, therefore that individual could not be included in the analysis of the effects of mind-wandering on either behaviour or physiology. The data for this individual was, therefore, included in the analysis of the distribution of Mind-wandering only.

⁶It is worth noting that in the analysis for the stimuli processed under the instruction to study information a reliable effect of Dysphoria Group was observed, F(1, 35) = 5.03, p<.05, indicating that fewer word fragments were correctly completed by individuals in the High Dysphoria Group (M=0.98, SD=0.12) than in the Low Dysphoria Group (M=1.36, SD=0.12).

⁷It is likely that this 2-way interaction is an artefact of the subsequent 3-way interaction.