Measures of rumination

In the following, we make a distinction between measures aiming to assess the stable tendency of individuals to engage in rumination (i.e., trait rumination) and measures aiming to assess the presence, quality or intensity of momentary rumination (i.e., state rumination).

Likewise, we present and discuss several types of measures, from self-reported measures to physiological measures. For each type of measure, we first present and discuss measures of trait rumination before turning to measures of state rumination.

Rumination has traditionally been assessed through self-administered questionnaires. The most commonly used measure of trait rumination is the Ruminative Response Scale (RRS) of the Response Style Questionnaire (RSQ, Nolen-Hoeksema & Morrow, 1991). The RSQ is an operationalisation of rumination as it was conceptualised in the response styles theory (Nolen-Hoeksema, 1991). The RRS consists of 22 items describing responses to dysphoric mood that are self-focused, symptom-focused, and focused on the causes and consequences of one’s mood. A short version of the scale containing ten items has been shown to be highly related (r = .90) to the full version of the questionnaire (Nolen-Hoeksema & Jackson, 2001). However, it has been argued that the RRS might contain overlapping items between rumination and depression (Treynor et al., 2003). In response to these concerns, Treynor et al. (2003) removed the ambiguous items from the original RRS and conducted a novel factor analysis. This analysis

revealed two distinct components: brooding and reflective pondering (as discussed in the previous section).

Based on Watkins (2008)’s distinction between constructive (concrete experiential thinking) and unconstructive (abstract analytical thinking) forms of rumination described previously, Barnard, Watkins, Mackintosh, & Nimmo-Smith (2007) developed the Cambridge Exeter Repetitive Thought Scale (CERTS) to assess different facets of rumination. This questionnaire contains 84 items arranged in three parts assessing i) the context of rumination, ii) the self-evaluation of the functionality of rumination and iii) ruminative processes. The short version of this questionnaire, the Mini-CERTS (Douilliez, Philippot, Heeren, Watkins,

& Barnard, 2012), contains 16 items extracted from the third part of the CERTS. These items evaluate more specifically the two dimensions identified by Watkins (2008). Interestingly, the concrete dimension of the Mini-CERTS appears to be related to the brooding dimension of the RRS, whereas no relation was found between the concrete dimension of the Mini-CERTS and other subscales from the RRS (Douilliez et al., 2012).

Several questionnaires have also been developed to assess the tendency to ruminate (i.e., trait rumination) as a transdiagnostic process. This includes (amongst others) the rumination-reflection questionnaire (Trapnell & Campbell, 1999), the repetitive thinking questionnaire (McEvoy, Mahoney, & Moulds, 2010) or the perseverative thinking questionnaire (Ehring et al., 2011). Several other measures have also been developed to assess more specific forms of repetitive thoughts or processes related to ruminative thoughts such as meta-cognitions, thought control or stress or sadness-reactive rumination (for a review of existing measures of rumination, see Luminet, 2004).

Rumination can also be seen as a momentary response (state rumination). The effects of state rumination are usually assessed in laboratory settings where rumination is induced and compared to another (more adaptive) form of emotion regulation such as distraction or problem-solving (for review, see Lyubomirsky, Layous, Chancellor, & Nelson, 2015). Some measures have been developed to assess state rumination but usually in reaction to specific events (e.g., stress-reactive, offence-reactive or sadness-reactive rumination). Moreover, until recently, there was no comprehensive and validated measure of state rumination. Nevertheless, the increasing use of the experience sampling methodology (Csikszentmihalyi & Larson, 1987) to investigate rumination in a more naturalistic environment led to the development of short scales that could be used quickly and repetitively throughout the day. For instance, Moberly & Watkins (2008) operationnalised momentary ruminative thinking using two items.

The first item asked participants to rate the extent to which they were focused on their symptoms, consistent with the conceptualisation of rumination of the response styles theory (Nolen-Hoeksema, 1991). The second item asked participants to rate the extent to which they were focused on their problems, consistent with self-regulation theories (Carver & Scheier, 1998; Martin & Tesser, 1996). Moberly & Watkins (2008) considered this two-item measure to reflect “ruminative self-focus”, independently of current (negative) affects. These two items are

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CHAPTER 1. THEORETICAL FRAMEWORK

rated on a scale from 0 (not at all) to 7 (very much), from which a mean score is then computed.³ Very recently, Marchetti, Mor, Chiorri, & Koster (2018) developed the Brief State Rumination Inventory (BSRI) to provide a more comprehensive and validated measure of state rumination.

They report two studies showing good reliability and validity of this scale in both its English and Dutch version. This questionnaire is composed of eight Visual Analogue Scales (VASs) ranging from “completely disagree” (numerically recoded as 0) to “totally agree” (numerically recoded as 100). These items are then summed to provide an indicator of momentary rumination. The BSRI is (to the best of our knowledge) the first validated full-length scale assessing momentary rumination.

Overall, the validity of self-report measures is based on the hypothesis that individuals have a reliable access to their internal states. However, we know self-reports increase reconstruction biases (e.g., Brewer, 1986; Conway, 1990). Moreover, we know that individuals usually have a low level of awareness of the cognitive processes that underlie their behaviours (Nisbett & Wilson, 1977). To overcome these difficulties, some authors have attempted to quantify state rumination and trait rumination more objectively, by recording physiological or neuroanatomical correlates of rumination (for review, see Siegle & Thayer, 2003). Peripheral physiological manifestations (e.g., pupil dilation, blood pressure, cardiac rhythm, cardiac variability) have been examined during induced rumination or in association with trait rumination. For instance, a consistent link between perseverative cognition and decreased heart rate variability (HRV) was found in a meta-analysis conducted by Ottaviani et al. (2016).

They also observed a positive association between (both trait and state) perseverative cognition and increased heart rate, systolic blood pressure, diastolic blood pressure, and cortisol activity (see also Zoccola & Dickerson, 2012, for a review of the relation between rumination and cortisol).

With regards to state rumination, Vickers & Vogeltanz-Holm (2003) have observed an increased systolic blood pressure after rumination induction, suggesting the involvement of the autonomic nervous system in rumination. Moreover, galvanic skin response has been shown to be increased after a rumination induction in highly anxious women (Sigmon, Dorhofer, Rohan,

& Boulard, 2000). According to Siegle & Thayer (2003), disrupted autonomic activity could provide a reliable physiological correlate of rumination. In this vein, Key, Campbell, Bacon,

& Gerin (2008) have observed a diminution of the high-frequency component of heart rate variability (HF-HRV) after rumination induction in people with a low tendency to ruminate (see also Woody, McGeary, & Gibb, 2014). Moreover, Zoccola, Rabideau, Figueroa, & Woody (2014) showed that the physiological consequences of rumination might depend on the level of construal (i.e., abstract vs. concrete). More precisely, they showed that an induction of abstract rumination led to lower blood pressure in comparison an induction of concrete rumination. Woody, Smolak, Rabideau, Figueroa, & Zoccola (2015) further showed that the

3The exact items are not specified in Moberly & Watkins (2008). However, Huffziger, Ebner-Priemer, Koudela, Reinhard, & Kuehner (2012) used a similar methodology and report the items they used, which were “At the moment, I am thinking about my feelings” and “At the moment, I am thinking about my problems”.

type of ruminative thought (imagery vs. verbal thought) was also associated with distinct physiological outcomes. They observed that verbal ruminative thoughts led to greater increases in heart rate than ruminative thoughts in a visual imagery modality. This effect was moderated by trait rumination and was only present in high ruminators.

In the present work, we used facial surface electromyography (in addition to self-reports) to investigate the muscular correlates of induced rumination. Before turning to a presentation of this experimental work however, we need to discuss why we think rumination can be considered a form of inner speech and how inner speech (and therefore, by inclusion, rumination) can be examined using surface electromyography.