Brain Research Bulletin 81 (2010) 565–573 Contents lists available at ScienceDirect Brain Research Bulletin journal homepage: www.elsevier.com/locate/brainresbull Research report The resting state questionnaire: An introspective questionnaire for evaluation of inner experience during the conscious resting state Pascal Delamillieure a,b,∗ , Gaëlle Doucet a , Bernard Mazoyer a,c , Marie-Renée Turbelin a,b , Nicolas Delcroix a , Emmanuel Mellet a , Laure Zago a , Fabrice Crivello a , Laurent Petit a , Nathalie Tzourio-Mazoyer a , Marc Joliot a a Centre d’Imagerie-Neurosciences et Applications aux Pathologies, UMR6232 CNRS, CEA, Universités de Caen et Paris Descartes, GIP-Cyceron, Bd Henri Becquerel, BP5229, 14074 Caen, France b Département Hospitalo-Universitaire de Psychiatrie, Centre Hospitalier et Universitaire de Caen, 14033 Caen cedex, France c Institut Universitaire de France et Centre Hospitalier et Universitaire de Caen, 14033 Caen cedex, France article info Article history: Received 7 October 2009 Received in revised form 27 November 2009 Accepted 29 November 2009 Available online 7 December 2009 Keywords: Consciousness Resting state Brain default mode Introspection Visual mental imagery Inner speech abstract We designed a semi-structured questionnaire for the introspective evaluation of inner experience of participants undergoing functional magnetic resonance imaging (fMRI) in the resting state. This resting state questionnaire (ReSQ) consists of 62 items organized by five main types of mental activity: visual mental imagery (IMAG); inner language (LANG), split into two subtypes, inner speech (SPEE) and auditory mental imagery (AUDI); somatosensory awareness (SOMA); inner musical experience (MUSI); and mental manipulation of numbers (NUMB). For IMAG and LANG, additional questions estimated association of such activities with ongoing learning, retrospective memories, or prospective thoughts. Using a 0–100% scale, the participant quantitatively rated the proportion of time spent in each mental activity during the resting state fMRI acquisition. A total of 180 healthy volunteers completed the ReSQ immediately after being scanned with fMRI while at rest. Of these, 66% exhibited dominance of a type of mental activity at rest (IMAG: 35%; LANG: 17%; SOMA: 7%; MUSI: 6%; NUMB: 1%). A majority of participants reported either retrospective memories (82%) or prospective thoughts (78%), with 58% of participants reporting both in at least one type of mental activity. Thoughts related to ongoing learning were low (37% of participants). The present results are consistent with those of previous studies investigating inner experience in a natural environment. In conclusion, we provide a robust and easy-to-implement tool for the exploration of mental activities during rest of healthy participants undergoing fMRI. This tool relies on normative data acquired from a 180-participant sample balanced for sex and handedness. © 2009 Elsevier Inc. All rights reserved. 1. Introduction A significant part of our wakeful brain activity is self-directed rather than goal-directed, consisting of periods of uncontrolled stream of thoughts, recollection of past episodes of our life, analysis of current inner sensations, thinking about problems, or planning for the future. This particular mind state, also referred to as “random episodic silent thinking” (REST) [1], “default mode” [34], or “con- scious rest” [4,28], has received increased attention in recent years because the corresponding brain state is both a physiological base- ∗ Corresponding author at: Centre d’Imagerie-Neurosciences et Applications aux Pathologies, UMR6232 CNRS, CEA, Universités de Caen et Paris Descartes, GIP- Cyceron, Bd Henri Becquerel, BP5229, 14074 Caen, France. Tel.: +33 0 2 31 47 01 10; fax: +33 0 2 31 47 02 22. E-mail address: delamillieure@cyceron.fr (P. Delamillieure). line [34] and a state of high neural activity and energy metabolism [38]. Several investigators have identified a large-scale cortical net- work with activity that appears to be maximal during REST and reduced during goal-directed cognitive tasks [4,28,30,31,37]. This network seems to support, at least in part, self-oriented activi- ties [1,4,7,12,19,28]. Modulation in brain default mode network activity due to life events, such as development [15,16], learning [27], aging [2,13], and neuropsychiatric diseases [36,39,43], has also been studied with the underlying hypothesis that the asso- ciated behavioral/cognitive changes or deficits may be related to such modulation. A major concern in all neuroimaging experiments addressing the resting state is the assessment of the participant’s mental con- tent while being imaged. First, the researcher must ensure that the participant has adequately followed instructions. Second, although some investigators have made efforts to perform online evalua- tion of the participant’s mental content while in the resting state 0361-9230/$ – see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.brainresbull.2009.11.014