Consciousness and Cognition 20 (2011) 1558–1569

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Consciousness and Cognition

journal homepage: www.elsevier .com/locate /concog

Implicit and explicit emotional behavior and mindfulness

Sebastian Sauer a,b,⇑, Harald Walach c,d, Stefan Schmidt c,d,e,f, Thilo Hinterberger d,g,Majella Horan c,d, Niko Kohls a,b,d

a Generation Research Program, Human Science Center, Ludwig-Maximilians-University, München, Germanyb Peter Schilffarth Institute for Sociotechnology, Bad Tölz, Germanyc Institute of Transcultural Health Studies, European University Viadrina, Frankfurt (Oder), Germanyd Brain, Mind and Healing Program, Samueli Institute, Alexandria, USAe Institute of Environmental Health Sciences, University Medical Center Freiburg, Germanyf University for the Humanistics, Utrecht, The Netherlandsg Department of Psychosomatic Medicine, University Hospital Regensburg, Germany

a r t i c l e i n f o a b s t r a c t

Article history:Received 22 December 2010Available online 31 August 2011

Keywords:MindfulnessEvaluative conditioningEmotional StroopEmotion

1053-8100/$ - see front matter � 2011 Published bdoi:10.1016/j.concog.2011.08.002

⇑ Corresponding author at: Generation Research P80417992911.

E-mail address: sauer@grp.hwz.uni-muenchen.d

The objective of this study was to examine whether the ‘‘step back and watch’’ attitude ofmindfulness manifests in less emotional behavior. We hypothesized that the ‘‘acceptance’’facet of mindfulness, but not the ‘‘presence’’ facet, is negatively associated with the mag-nitude of emotional behavior in four tests, i.e., (1) rating of words, (2) rating of aversiveand neutral pictures, and (3) evaluative conditioning (EC). Additionally, we hypothesizedthat (4) the acceptance facet is associated with increased reaction time (RT) in an emo-tional Stroop test, and that the presence facet is associated with decreased RT and lowererror rate. The sample consisted of N = 247 non-clinical adults and was tested in a cross-sectional study. The results provide partial evidence that the acceptance facet of mindful-ness may be associated with less aversive reactions towards aversive stimuli. Future stud-ies should substantiate these findings but also determine their clinical relevance.

� 2011 Published by Elsevier Inc.

1. Introduction

Mindfulness has become a focus of research interest in the health sciences. Mindfulness as a state of consciousness maybe characterized by an attentional stance bearing on the present moment (‘‘presence’’) with a non-judgmental attitudetowards all perceptions and sensations (‘‘acceptance’’) associated with the actual experience (Kohls, Sauer, & Walach,2009). In more functional terms, the less an individual assesses a stimulus to be emotionally loaded while attending to pres-ent moment experience, the more proficient in mindfulness this individual can be considered. Mindfulness is not the same ashypnotic suggestibility although some empirical overlap has been reported (Walach, Buchheld, Buttenmüller, Kleinknecht, &Schmidt, 2006). Being in a hypnotic state can be accompanied either by a heightened or reduced level of awareness, as isobserved in states of dissociation, absorption and trance (Roche & McConkey, 1990). In contrast, the state of being mindfulis always associated with voluntarily maintained awareness and alertness.

Several meta-analytical reviews (Chiesa, Calati, & Serretti, 2011; Chiesa & Serretti, 2009; Grossman, Niemann, Schmidt, &Walach, 2004; Mars & Abbey, 2010) have investigated the relationship between mindfulness, health and wellbeing and havecorroborated the health-relevant effects of mindfulness. A substantial number of controlled trials suggest that mindfulnesscan be trained, for example via meditative, contemplative or specific mind–body techniques (Baer, 2003). Although the

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e (S. Sauer).

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clinical relevance of mindfulness seems to be substantiated (Hofmann et al., 2010), the psychological mechanisms related tomindfulness are less clear. To date, several attempts have been made to clarify the emotional and cognitive processes asso-ciated with mindfulness (Arch & Craske, 2006; Sauer, Walach, & Kohls, 2011; Shapiro, Carlson, Astin, & Freedman, 2006). Forexample, Arch and Craske (2006) have presented data suggesting that mindfulness may help with alleviating emotional reac-tions towards aversive stimuli. They found that after a period of being mindful, their participants rated aversive pictures asless negative compared to control groups. This empirical finding seems to be in accordance with theoretical models such asthose found in Buddhist psychology, a major theoretical source of mindfulness, in which staying equanimous in the face ofboth unpleasant and pleasant experiences is deemed to be the central aspect of mindfulness (Hart, 1991). Yet, there is stilllittle experimental data available on this central claim of mindfulness theory, especially with regard to implicit behavioralmeasures, as opposed to explicit self-report data.

There are, nevertheless, theoretical components available that may be used to explain at least some psychological aspects ofmindfulness in terms of cognitive neuroscience. The ability to be present may be interpreted as being related to attentional net-work processes associated with alerting (Posner & Petersen, 1990). Alerting may be understood as the psychological functionthat Wilhelm Wundt, following Leibniz, called apperception, i.e. achieving and maintaining a high sensitivity to perceivingincoming stimuli or, more generally, as the alignment of attention to a sensory signal. This function has been associated withthalamic as well as frontal and parietal regions of the brain (Posner & Petersen, 1990). Brown and Ryan (2003) perceived theability to be present – a key feature of mindfulness – as voluntarily sustaining consciousness of external or internal stimuliby simultaneously upholding awareness and attention. In their conceptualization, awareness and attention can be conceivedas complementary psychological functions. While awareness can be understood as a voluntarily intensified level of generic vig-ilance allowing an individual to monitor a broad array of stimuli with a rather coarse-grained detail resolution, attention ischaracterized by intentionally focusing on a restricted range of stimuli with a more fine-grained detail resolution (Brown &Ryan, 2003; Westen, 1999). Both attention and awareness processes are, according to Brown and Ryan, important for modu-lating sensory perception so that efficient pattern recognition can be established, as their interplay allows the continuous con-struction, deconstruction and adaptation of gestalt phenomena in the foreground against background stimuli. Theirconceptualization – conceiving awareness and attention as intertwined, complementary processes – can be seen as being inline with cognitive neuroscience models of differential ventral and dorsal alerting systems (Jha, Krompinger, & Baime,2007). In short, the right-lateralized, fronto-parietally based ventral system is predominantly activated by abrupt changes insensory stimuli, especially if something occurs outside the focus of current attention (Corbetta & Shulman, 2002). In contrast,the dorsal system is primarily activated by presentation of cues to which participants should direct their attention.

The emotional aspect of mindfulness, usually attributed to its acceptance facet, has been shown to be associated withemotion-regulation brain regions such as the prefrontrol cortex (PFC), the insula or the anterior cingulate cortex (ACC; Ben-son et al., 2005; Hölzel et al., 2008). In one study, Davidson and colleagues found evidence for left-sided anterior activation, apattern previously associated with positive affect (Davidson et al., 2003). Davidson and Irwin (1999) propose that two emo-tional systems, the approach and the withdrawal system, may explain emotional behavior and that this approach may wellbe mapped to neural circuitry. In short, the approach system is considered to be responsible for appetitive behavior and cer-tain forms of positive emotions, whereas the withdrawal system may lead to pull back behavior as a reaction to sources ofaversive stimulation (Gray, 1988, 1994). Recent findings suggest that mindfulness is negatively related to withdrawal behav-ior tendency (Sauer, Walach, et al., 2011). The tendency to fall prey to withdrawal motivations have been found to be asso-ciated with maladaptive behavior (Harmon-Jones, 2003). Thus, it may be speculated that the health-relevant effects of theacceptance facet of mindfulness might be facilitated by its ability to mitigate withdrawal tendencies.

More experimental research is needed, however, to understand the underlying cognitive-emotional processes related tothese two subfacets of mindfulness. It may well be that these subfacets are associated with separate mechanisms of action ofmindfulness, particularly as they are presumably realized by distinctive, but intertwined, neuronal processes. However,although conceptually distinct, both presence and acceptance are simultaneously required to exert the ability to be mindful.

To date, a variety of questionnaires have been constructed to assess mindfulness (Brown & Ryan, 2003; Feldman, Hayes,Kumar, Greeson, & Laurenceau, 2007; Kohls & Walach, 2006; Wagner, Rathus, Miller, & Baer, 2006). Most of these scales as-sess mindfulness as a rather stable ‘‘trait’’ construct, with the exception of the Toronto Mindfulness scale, which tries togauge the current ‘‘state’’ level of mindfulness (Lau et al., 2006). The majority of mindfulness questionnaires have concep-tualized mindfulness as a construct with two distinct, yet interrelated, facets: presence and acceptance. For example, the fivefactors of the Five Facet Mindfulness Questionnaire (Baer, 2003) implicitly draw on a presence facet (describing, observing,acting with awareness) and an acceptance facet (non-reactivity, non-judging). One exception is the Mindfulness Attentionand Awareness Scale, which conceptualizes mindfulness as consisting of presence alone (Brown & Ryan, 2003). However,the theoretical underpinnings and definitions of how mindfulness should be conceived as well as the operationalizationby means of the respective questionnaire instruments differ considerably between scales (Offenbächer et al., 2011).

It is, therefore, the aim of this study to deepen the understanding of potential mechanisms of mindfulness by not onlyrelying on questionnaire instruments, but also scrutinizing different forms of emotional behavior. Specifically, we aim toinvestigate whether mindfulness is associated with less emotionally aroused reactions towards aversive stimuli in four dif-ferent types of emotional behavioral responses: word rating, picture rating (explicit measures), susceptibility to evaluativeconditioning (EC), and emotional Stroop test (ES; implicit measures). In a second step, we scrutinize whether theseassociations are driven by the acceptance facet of mindfulness only. The rationale for this hypothesis is based on the findingthat only the acceptance facet of mindfulness, and not the presence facet, has been found to be involved in changes in

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emotion-related mental health indicators such as depression or anxiety (Kohls et al., 2009). Moreover, our conceptualiza-tions are in line with recent research suggesting that disease acceptance is a protective coping factor for vulnerablepopulations (Büssing, Matthiessen, & Mundle, 2008; Isikhan et al., 2001). However, as pointed out above, the presence facetis also necessary as it can be seen as a vehicle for developing, enhancing and fortifying acceptance.

1.1. In summary, we posit the following hypotheses

(1) Acceptance, but not presence, is correlated with a more positive rating of the emotional valence of words and pictures,as an accepting stance toward such stimuli should manifest itself in less aversive reaction, i.e. less aversive ratings ofthe stimuli.

(2) We hypothesize that the acceptance facet of mindfulness is negatively correlated with the degree of susceptibility tothe conditioning of aversive stimuli. In other words, the higher the individual level in the acceptance facet of mind-fulness, the less the individual is prone to be affected by the conditioning of aversive stimuli. It has been advocatedthat conditioning of emotional stimuli may be causally connected to the learning of fear (Lazarus, 1991). This mech-anism might provide a possible explanation for the fact that mindfulness might reduce fear (McCracken & Keogh,2009).

(3) We additionally hypothesize that the acceptance facet is related to slower reaction time (RT) in an ES test, i.e., indi-viduals scoring higher on the acceptance facet of mindfulness should react slower than individuals scoring lower onthis facet. The rationale for this hypothesis is the assumption that acceptance allows overruling of automatic reactionstowards aversive stimuli by means of neuronal top down processing, which might manifest itself in slower reactionstimes.

(4) However, given that the presence facet of mindfulness seems to be associated with improved attentional resources, weexpect that presence is associated with a shorter RT in the ES test, and thus may be acting opposite to the acceptancefacet. In fact, evidence for substantial increased attentional capabilities of mindfulness training has been reported(Slagter et al., 2007). On this basis, we assume that the presence facet is correlated with a faster RT and lower errorrates in the ES.

A consequence of this reasoning is that, should the two subfacets act in opposite directions on RT and error rate in the EStest, a potential effect of mindfulness may actually be blurred if the total mindfulness score is used as a generic predictor.However, if the differential effects of the acceptance and presence facet of mindfulness can be confirmed, a strong claim forthe validity of the cognitive-emotional effects of mindfulness and the self-report measurement of mindfulness as a twofoldconstruct would be established.

2. Methods

2.1. Participants

The sample consisted of N = 247 German non-clinical adults, of which n = 94 (38%) were male and n = 153 (62%) female. Themean age was M = 29.4 years (SD = 8.9). Eighty-three participants (34%) reported a regular form of meditative training (such asZen). Two hundred and thirty-three individuals (94%) provided data via our internet portal research site www.mindfulness-re-search.net. Participants were addressed through student union boards and websites such as those of health and psychotherapyorganizations. To make participation equally attractive for people with or without prior personal interest and training in mind-fulness, we included entry in a prize draw for a pocket PC as a reward for participation. To ensure data quality, we followed theguideline for internet-based experimenting as presented by Reips (2002).

2.2. Measures

Internal consistency (Cronbach’s alpha) as found in the present data is reported in Table 1 for all psychometric scales. Thescale range for each instrument is also reported in Table 1.

2.2.1. MindfulnessThe Freiburg Mindfulness Inventory (FMI) is a 14-item self-report measure with good psychometric properties including

high internal consistency (alpha = .87; Walach et al., 2006). The scale conceptualizes mindfulness as a unidimensional con-struct with two highly correlated factors, ‘‘presence’’ and ‘‘acceptance’’ (Kohls et al., 2009). Sample items for the presenceand acceptance facet are ‘‘I am open to the experience of the present moment’’ and ‘‘In difficult situations, I can pause withoutimmediately reacting.’’ Additionally, mindfulness was assessed as a binary criterion ‘‘regular mindfulness practice’’ or lack of it.

2.2.2. Mental distressMental distress was assessed with two instruments assessing depression and anxiety. Firstly, the simplified version of the

Beck Depression Inventory (BDI) (Schmitt et al., 2003), a well validated scale with 20 items and a high internal consistency

Table 1Descriptive statistics and intrasample comparisons.

Mean(sd) fullsample

Mean(sd)practitioners

Mean(sd) non-practitioners

Internal consistency inthis sample*

t(df = 245) p Cohen’sd

Anxiety** 2.77(.76) 2.54(.71) 2.88(.76) .92 3.323 .001 �.46Depression** 2.10(.65) 1.93(.59) 2.18(.67) .90 2.94 .004 �.40Self-report mindfulness** 4.04(.67) 4.27(.69) 3.92(.62) .84 4.03 <.001 .53Presence facet** 4.22(.78) 4.46(.77) 4.10(.76) .73 �3.49 .001 .47Acceptance facet** 3.98(.92) 4.21(.91) 3.86(.91) .63 �2.81 .005 .38Word-rating t0** 3.27 (.37) 3.32(.39) 3.24(.36) .68 �1.65 .10 .25Word rating t1 (neutral)** 3.22(.51) 3.34(.51) 3.16(.50) – �2.69 .008 .36Word rating t1 (aversive)** 3.17(.53) 3.31(.51) 3.23(.43) – �1.80 .08 .17Picture rating (neutral)** 3.19(.50) 3.21(.49) 3.18(.51) – �.48 .64 .06Picture rating (aversive)** 1.81(.44) 1.82(.48) 1.80(.42) – �.46 .64 .04Reaction times ES

(aversive) (in ms)791.14(112.72) 825.82(130.60) 773.48(98.25) – �3.16 .002 .46

Reaction time ES (neutral)(in ms)

791.20(112.86) 827.90(124.66) 772.50(101.77) – �3.43 .001 .49

EC*** (neutral) �.06(.46) .008(.37) �.10(.49) – �1.68 .09 .25EC*** (aversive) �.12(.59) �.08(.50) �.13(.63) – �.66 .51 .09Error rate in ES (neutral) 41.23%(2.95%) 40.63%(1.33%) 41.41%(3.43%) – 2.56 .01 .33Error rate in ES (aversive) 41.13%(2.36%) 40.78%(1.50%) 41.23%(2.86%) – 1.75 .08 .22

Notes. sd = standard deviation. ms = milliseconds. t, p and Cohens’s d values refer to the mean differences between mindfulness practitioners and non-practitioners.* Measured by Cronbach’s alpha.** Scale ranged from 1 to 6; higher values indicate higher levels of anxiety, depression, mindfulness, or pleasantness of the word or picture.*** Measured as difference in word rating between t1 and t0.

Table 2Regression on Stroop RT in neutrally and aversively conditioned trials in emotional Stroop test.

B SE b t p

Neutrally conditioned trialsConstant 676.54 73.92 9.15 .000Acceptance 10.49 10.16 0.09 1.03 .303Presence �23.80 9.78 �0.16 �2.43 .016Age 5.91 0.82 0.44 7.18 .000Sex �33.64 14.00 �0.14 �2.40 .017Anxiety 6.06 17.06 0.04 0.36 .723Depression 4.65 18.04 0.03 0.26 .797

Aversively conditioned trialsConstant 655.71 74.73 8.77 .000Acceptance 13.05 10.27 0.11 1.27 .205Presence �22.09 9.89 �0.15 �2.23 .026Age 5.80 0.83 0.43 6.97 .000Sex �26.51 14.16 �0.11 �1.87 .062Anxiety 12.88 17.25 0.09 0.75 .456Depression �3.38 18.23 �0.02 �0.19 .853

Notes. B = unstandardized regression coefficient. SE = standard error. b = standardized regression coefficient. T = t-value.

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(a = .91) was utilized. Secondly, the 20 item trait subscale of the State-Trait-Anxiety-Inventory (STAI; a = .91) was employed.The STAI is a well established self-report assessment device for independently measuring state and trait anxiety on two sub-scales with high internal consistency (Spielberger, 1983). Sample items for the BDI and STAI are ‘‘I feel discouraged about thefuture.’’ and ‘‘I feel frightened’’.

2.2.3. Assessment of emotional behavior2.2.3.1. Word rating. We composed a list of twenty neutral words that were to be rated by the participants regarding theemotional valence of each word. Ten words were normal, sensible terms such as ‘‘bread’’, while ten words were pseudo-words (PW) such as ‘‘toch’’: See Appendix A for a list of the words. Words and PW were counterbalanced for the numberof syllables. PW were used because semantic content and emotional connotation of normal words may represent a con-founder (Richards & Blanchette, 2004).

2.2.3.2. Picture rating. Sixty pictures (30 aversive and 30 neutral) taken from the International Affective Pictures Program(Lang, Bradley, & Cuthbert, 1999) were used as stimulus material; see Appendices B and C for their emotional valences. Aver-sive pictures were chosen to be moderately repulsive (emotional valence: M = 2.77; SD = 1.61); we did not present pictures

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showing explicit violence. Neutral pictures were chosen to evoke as little emotional reaction as possible (emotional valence:M = 4.96, SD = 1.11). Typical pictures that were shown depicted animals considered to be aversive or dangerous such as spi-ders, or showed sad or crying people, or people bearing firearms. Neutral pictures included neutral daily objects such as achair. We included neutral pictures as previous research has shown that even with neutral pictures EC may take place pro-vided that aversive-conditioned trials are performed simultaneously (Richards & Blanchette, 2004). However, the EC effectwas found to be weaker for neutral-conditioned trials compared to aversive-conditioned trials.

2.2.3.3. Evaluative conditioning. Susceptibility to EC refers to the individual change in the evaluation of a stimulus resultingfrom the combined presentation of the stimulus with other (positive or negative) stimuli (Martin & Levey, 1978). In EC stud-ies, a neutral stimulus is paired with an affective stimulus, and the change in the preference for the neutral stimulus is thenassessed. Empirical evidence suggests that changes in preferences are subject to learning processes rather than inherent toindividuals, and that EC may play a crucial role in the learning of personal preferences and fear (Rozin & Millman, 1987).Researchers agree that emotions are closely linked to preferences (Lazarus, 1991). Hence, susceptibility to EC, understoodas an individual trait characteristic, may be seen as a risk factor for exhibiting aversive emotional behavior. As a previousstudy found that the inverse relationship between mindfulness and anxiety and depression was established only by theacceptance component (Kohls et al., 2009), we hypothesize that the acceptance facet of mindfulness may be negatively cor-related with susceptibility to EC in an experimental design. In addition to aversive pictures, we also included neutral picturesto test the differences in aversive and neutral stimulus material in EC.

2.2.3.4. Emotional Stroop test. In the ES test, participants were asked to identify the color of emotionally loaded words such as‘‘death’’ presented on a computer screen. It has been argued that mood-disordered or distressed participants – such asdepressive patients – show greater RT in the ES compared in comparison to non-clinical participants who show less or nointerference at all (Becker, Rinck, Margraf, & Roth, 2001). This interference effect on color-naming was also found in ameta-analysis (Peckham, McHugh, Kathryn, & Michael, 2010). RT was defined as the time period between onset of stimuluspresentation and the time the button was pressed by the participant.

2.3. Design, procedures, and technical setup

Data was collected in a cross-sectional design. In a computerized setting, each participant completed the following steps:(1) Informed consent. Participants were fully informed about the aims of the study and were asked to give informed consentbefore continuing. (2) Administration of self assessment instruments. Mindfulness, depression, and anxiety levels were mea-sured, and demographic data was collected. (3) First assessment of the emotional valence of words (t0). Participants were thenasked to assess the emotional valence of each of the 10 normal words and 10 PW. All words were presented in a randomorder for each participant with normal words and PW intermingled. (4) Evaluative conditioning. For each trial of EC, oneof the 20 words was presented on the screen, and 500 ms later a picture appeared. After another 1500 ms the participantswere asked to assess the emotional valence of the picture. Ten of these 20 words were randomly assigned to the 30 aversivepictures: The other 10 words were randomly assigned to the 30 neutral pictures. Hence, each word was associated with threepictures of the same type, forming either an aversive or neutral valence set of words. Half of the participants started withaversive pictures and continued with the neutral ones, while the other half began with neutral pictures. The picture orderfor both the aversive and the neutral word sets were randomized. Altogether, 120 trials were conducted. (5) Second assess-ment of emotional valence of words (t1). The same procedure was repeated as for the first assessment of the words. (6) Emo-tional Stroop test. Participants were presented again with one of the 20 words and were asked to press, as quickly as possible,the respective keyboard button corresponding to the color in which the word was presented on the screen. This procedurewas repeated for all 20 words. This block of 20 trials was repeated 6 times, so that each word was presented six times, total-ing 120 trials. Each of the words was presented in one of four colors on the screen until a manual response was made.

As data was collected online, the computer hardware could not be controlled. The experimental software was pro-grammed using C++. The software program was designed to cover the whole screen, and to suppress any other PC processesin order to prevent interferences during the RT measurement. The stimuli size was about 200 pixels (visual angle of about6.6� for a typical laptop viewing distance of approx. 0.60 m). We used the Marsenne Twister algorithm for generating reliablerandom numbers (Matsumoto & Nishimura, 1998). All other experimental and technical details were comparable to the de-sign of the EC and ES suggested by Richards and Blanchette (2004).

3. Results

3.1. Data analyses

Alpha was set to .05 (two-tailed). Linear correlations (Pearson’s r) were computed for scrutinizing the association be-tween mindfulness, mental distress, word and picture rating. For comparing the effects of either of the two mindfulness fac-ets with mental distress, word and picture rating, we used partial correlation to control for the effect of the respective otherfacet. T-tests for dependent samples were used to assess whether the EC effect could be established. Linear regressions

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(‘‘enter’’ method) were employed for assessing the effect of mindfulness on EC and on ES. T-tests for independent sampleswere used for testing the differences in all dependent variables between individuals with and without regular mindfulnesspractice. Visual inspection of the graphs was used to check if the assumptions of the statistical tests (linearity, homoscedas-ticity, independence of residuals, normality) were met to an acceptable degree (Cohen, Cohen, West, & Aiken, 2002). SPSSV18 was used for computations. In accordance with established protocols for using RT in the ES (Richards & Blanchette,2004) and in the Implicit Association Test (Greenwald & Banaji, 1995), RT was computed on the basis of the mean value.Raw data of RT were prepared as follows: only trials with mean value of 300 ms < RT < 1500 ms and only trials with correctanswers were included into RT analysis. Individuals with more than 20% incorrect trials were excluded. However, none of theparticipants was excluded as a result of this procedure.

3.2. Mindfulness, depression, and anxiety

First, we calculated descriptive statistics (see Table 1) and first-order correlations between RT, mindfulness, depression,and anxiety levels. The total mindfulness score (consisting of presence and acceptance) was found to be negatively correlatedwith depression (r = �.54; p < .001) and anxiety (r = �.60; p < .001). To assess the correlation between the acceptance (pres-ence) facet and the two mental distress measures, we controlled for the presence (acceptance) facet as the two mindfulnessfacets were found to be intercorrelated. For the acceptance facet, the partial correlation was similar to the correlation of thetotal mindfulness score with each of the two mental distress measures (depression: r = �.50; p < .001; anxiety: r = .62;p < .001), whereas for the presence facet, no correlation was present when controlling for the acceptance facet (depressionr = .04; p = .54; anxiety: r = �.06; p = .35), as expected. We additionally compared mean scores for self-reported mindfulness,depression, and anxiety between practitioners of mindfulness (n = 83) and non-practitioners (n = 164) using t-tests for inde-pendent samples. Individuals with regular practice assessed themselves as being more mindful, less depressed, and less anx-ious; effect sizes for the group differences (Cohen’s d) were found to be low to moderate (see Table 1).

3.3. Mindfulness and word rating

Second, the partial correlation between the rating of the emotional appraisal of neutral words at t0 (before pairing withpictures), and self-reported mindfulness was tested. Higher values in the emotional evaluation score indicate a more positivesentimental rating of the respective neutral word. As expected, the acceptance facet of mindfulness was significantly corre-lated with the rating of word valence when controlling for the presence facet. Conversely, the presence facet was not corre-lated with word rating when controlling for acceptance (acceptance: r = .21, p < .001; presence: r = .12, p = .07). Third, weanalyzed if the partial correlation between the presence facet and word-rating for PW differed from the correlation betweenpresence and word-rating for normal words. The same analysis was conducted for the acceptance facet of mindfulness. Thisanalysis controls for the potential confounding of the semantic influence of known normal words compared to non-words. Forboth the presence and the acceptance facet, the correlations did not differ significantly; a Fisher-Z-transformation yielded a p-value for the comparison of the r’s of p = .91 for presence, and p = .82 for acceptance, respectively. This suggests that there wasno significant difference in the emotional appraisal between PW and words. Additionally, comparing mindfulness practitio-ners and non-practitioners, no effects in word-rating at t0 were found.

3.4. Mindfulness and picture rating

The partial correlation between the rating of neutral pictures with self-reported mindfulness was neither significant forthe acceptance facet of mindfulness (r = .10, p = .09) nor for the presence facet (r = .01; p = .82). Regarding the aversive pic-ture rating, none of the two mindfulness facets were found to be correlated significantly with picture rating (acceptance:r = .04; p = .55; presence: r = �.03; p = .63), contrary to expectations. Practitioners and non-practitioners did not show signif-icant differences in picture rating (see Table 1).

3.5. Mindfulness and evaluative conditioning

In the next step, we tested whether EC could be found in our data, or more precisely, if words had been rated more aver-sively after the pairing condition (t1) than before pairing (t0), employing paired t-tests for dependent samples. For wordsthat were paired with aversive pictures, as well as for words that were paired with neutral pictures, EC could be established(aversive trials: difference t1 � t0 = �.09, SD = .48, t(246) = �3.13, p = .003; neutral trials: difference t1 � t0 = �.06, SD = .46,t(246) = �2.10, p = .04). Thus, even the trials conditioned with neutral pictures had been affected by emotional aversion, car-ried over from the trials conditioned with aversive pictures.

For assessing the contribution of self-reported mindfulness on the EC effect, a multiple regression analysis with the twomindfulness facets and with word rating at t0 as predictors and word rating at t1 as dependent variable were conducted sep-arately for aversive and neutrally conditioned trials. For neutrally conditioned trials (i.e., where the neutral words werepaired with neutral pictures), results supported the hypothesis. The acceptance facet exerted a statistically significant influ-ence on EC (b = .12, t = 2.01, p = .046), in contrast to the presence factor (b = �.01, t = �.12, p = .90); R2

adj ¼ :29. For aversivelyconditioned trials (i.e., where the neutral words were paired with aversive pictures), however, the acceptance facet showed

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only borderline significance (b = .10, t = 1.73, p = .09), and the presence factor did not exert a significant influence (b = �.04,t = �1.05, p = .30); R2

adj ¼ :29. Practitioners and non-practitioners tended to show differences for EC in neutrally conditionedtrials in the expected direction, but not in aversively conditioned trials (see Table 1). As no differences in the correlation anal-yses between mindfulness and word-rating was detected for PW and normal words, we refrained from testing a semanticconfounder effect for the EC and ES tests.

3.6. Mindfulness, reaction time and error rate in the emotional Stroop

We employed a multiple regression with RT (mean value) as dependent variable and the two mindfulness facets presenceand acceptance as predictors to estimate the influence of these variables on RT and error rate in the ES. Since biological ageexhibits a strong influence on motor performance tasks, and anxiety along with other forms of mental distress tends to in-crease RT in the ES, we controlled for age, anxiety and depression by including them as independent variables in the regres-sion (De Ruiter & Brosschot, 1994; Mattay et al., 2002; Richards & Blanchette, 2004; Smith, 1999). Additionally, sex (dummycoded: 0 = male; 1 = female) was included as an independent predictor in order to detect potential gender effects. Gendereffects are a common finding (Feingold, 1994), and therefore neglecting subgroup differences could distort the outcome(Wagner, 1982).

Two regression analyses were computed, one for neutrally conditioned and one for aversively conditioned trials, respec-tively. For neutrally conditioned trials, the presence facet of mindfulness, as well as age and sex were significant predictors(men reacting slower than women; see Table 2), but not the acceptance facet, anxiety, and depression; the amount of var-iance explained by the model was R2

adj ¼ :21. As expected, individuals higher in presence tended to react faster than individ-uals lower in presence; however, the acceptance facet did not exert a substantial effect. In summary, the results partlyconfirm the hypothesis.

For aversively conditioned trials, the regression yielded a similar picture. Again, the presence facet of mindfulness wassignificant, as was age, whereas in this case no significant effect was found for sex. The effects of the acceptance facet,depression and anxiety were not significant (see Table 2); R2

ad ¼ :19. However, the RT in the ES was significantly differentbetween practitioners and non-practitioners for both neutral and aversive trials, with practitioners reacting slower (see Ta-ble 1). This finding indirectly supports the hypothesis that acceptance decelerates the RT since practitioners are expected tohave higher levels, particularly in the acceptance facet, compared to non-practitioners (Kohls et al., 2009). It is worth notingthat when using the total mindfulness score as a predictor instead of the two facets presence and acceptance, the effect ofmindfulness was no longer significant (aversive: B = �1.55; SE = 12.58; =.90; neutral: �7.53; SE = 12.46; p = .55). This findingsuggests that using the total mindfulness score may blur results for behavioral tests where the two mindfulness facets havedifferential effects. We furthermore checked whether the two subgroups showed different scores in speed-accuracy tradeoff.It would be plausible that mindfulness practitioners arrive at better tradeoff values given that they have more attentionalresources and are less susceptible to emotional disturbances by the aversive stimuli. Differential speed-accuracy effects be-tween the groups should be reflected by differential correlation patterns for speed and accuracy. Our statistical analyses didnot detect any differences in speed-accuracy tradeoff between the two groups as the correlation between speed and accuracywas neither significant in the practitioners group (aversive trials: r = .08; p = .51; neutral trials: r = .19; p = .19), nor in thenon-practitioners group (aversive trials: r = .04; p = .67; neutral trials: r = .09; p = .25).

We used the same predictors for gauging the impact of the two subfacets of mindfulness on error rate again in two sep-arate regression analyses. In the analysis for neutrally conditioned trials, only the presence facet was significant, as expected(see Table 3), indicating that higher presence may lead to less error in the ES. The amount of variance explained by the modelwas, however, small (R2

ad ¼ :04). In the analysis for aversively conditioned trials, the presence facet was slightly weaker thanin the previous analysis and exhibited borderline significance (p = .07; see Table 3; R2

adj ¼ :03). None of the other predictorsexerted a significant influence on the error rate either for neutrally or aversively conditioned trials. We also tested groupdifferences in error rates. Practitioners showed significantly less errors in the neutral trials; for the aversive trials, no groupdifferences were present (Table 1).

4. Discussion

The purpose of the present research was to test whether self-attribution of mindfulness is associated with less aversivereactions towards aversive stimuli. This hypothesis was tested using two explicit and two implicit emotional behaviorparadigms (word rating, picture rating, EC, ES; see Table 1). We decided to test our assumption on the basis of splitting mind-fulness into the two subfacets, presence and acceptance, as suggested by theoretical conceptualizations. In short, the abilityto be present is likely to be related to attentional regulation, while acceptance is probably involved in regulation of emotions.

With regard to the two explicit conditions, word and picture rating, the results partly support our assumption that mind-fulness is associated with more positive or less aversive explicit emotional reactions, and that this association is predomi-nantly driven by the acceptance facet. For the word rating test, the acceptance but not the presence component ofmindfulness was indeed positively associated with a more positive word rating. This is in line with our hypothesis thatthe acceptance facet alone is associated with the emotional appraisal of presented stimuli, in our case words. For picture rat-ing, however, our hypotheses could not be confirmed. Neither the acceptance nor the presence facet was correlated with the

Table 3Regression on number of correct trials in neutrally and aversively conditioned trials in emotional Stroop test.

B SE b t p

Neutrally conditioned trialsConstant 56.59 2.04 27.79 .000Acceptance �0.35 0.28 �0.11 �1.26 .208Presence 0.71 0.27 0.19 2.69 .008Age �0.35 0.48 �0.09 �0.72 .470Sex 0.08 0.50 0.02 0.16 .872Anxiety 0.04 0.02 0.11 1.73 .085Depression 0.59 0.39 0.10 1.53 .128

Aversively conditioned trialsConstant 57.70 1.62 35.71 .000Acceptance �0.19 0.22 �0.08 �0.84 .403Presence 0.39 0.21 0.13 1.84 .067Age �0.10 0.38 �0.03 �0.27 .786Sex �0.08 0.40 �0.02 �0.20 .841Anxiety 0.02 0.02 0.09 1.38 .170Depression 0.15 0.31 0.03 0.49 .623

Notes. B = unstandardized regression coefficient. SE = standard error. b = standardized regression coefficient. T = t-value.

S. Sauer et al. / Consciousness and Cognition 20 (2011) 1558–1569 1565

emotional appraisal of the aversive and neutral pictures. This may be due to the fact that participants were not explicitlyinstructed to be mindful during the experiment, so that the actual mindfulness state was not strong enough to exert an influ-ence. It is also possible that the acceptance facet, conceptualized as a general, abstract non-judgmental attitude, is morelikely to influence the emotional appraisal of more abstract semantic categories, such as the words, compared to more con-crete and tangible pictures. However, these explanations remain speculative and post hoc interpretations.

With regard to the two implicit testing conditions, EC and ES, results are more difficult to interpret. As expected, the effect ofthe acceptance factor on EC in trials with neutral pictures was significant, whereas no effect was found for the presence facet.However, in EC trials with aversive pictures, the acceptance factor fell shortly below statistical significance. This finding seemsto be counterintuitive at first glance, as mindfulness is frequently thought to reduce the impact of aversive stimuli on an indi-vidual. However, as already pointed out, we did not explicitly ask our participants to be mindful during the experimental sit-uation. Thus, for the distinct aversive-conditioned trials, the acceptance level of the participants may have not been strongenough to exert an influence on EC. In contrast, the neutral-conditioned stimuli took on some negativity, but less than thatof the aversive-conditioned trials. Thus for those stimuli, acceptance/ mindfulness was shown to be able to exert an influenceon EC. We opine that the results of the EC test are of particular interest given the widespread occurrence of automatic learningprocesses of preferred and unpreferred stimuli in everyday life, as well as their clinical importance, particularly in the context offear development (Olatunji et al., 2009). It is noteworthy that, in line with previous research, ES took place for aversive-condi-tioned trials as well as for neutral-conditioned trials (Richards & Blanchette, 2004). This fact may be explained by carry-overeffects from the aversive onto the neutral trials. Thus, the neutral stimuli took over some of the adversity of the aversive stimuliduring the EC, a finding previously reported in implicit measures of emotion (Waters, Sayette, & Wertz, 2003).

The ES regression tests also revealed partly unexpected but nevertheless interesting results. Individuals with higher self-assessed presence scores reacted faster and with a lower error rate, as predicted, both in aversively and neutrally conditionedtrials. Contrary to what was expected, the acceptance facet did not exhibit a statistically significant effect on RT. One expla-nation may be, again, that this study did not explicitly ask individuals to be mindful while conducting the experiment, so itmay be speculated that the actual mindfulness level in the experimental setting was undetermined. An indirect support forthe ‘‘step back’’ effect of the acceptance facet may be derived from the fact that practitioners reacted slower in the ES thannon-practitioners, even if controlled for age and gender. Practitioners are expected to have higher RT particularly in theacceptance facet compared to non-practitioners (Kohls et al., 2009). As the presence facet is supposed to build up foremostwhen someone starts to practice mindfulness, novices and more experienced mindfulness practitioners might share similarlevels in presence proficiency. In contrast, according to our theory, acceptance is expected to build up later in the progress ofthe practice. Thus, only practitioners with substantial level of mindfulness training should achieve high scores in theacceptance facet. Therefore, with higher scores in the acceptance facet, proficient practitioners should react slower comparedto individuals with less practice who should react relatively fast in the ES test. It may seem unexpected at first glance that thetwo facets of mindfulness work in opposite directions to RT. However, it fits well with the theory of mindfulness in whichattention and concentration play a role but co-exist with a non-reactive, passive stance of withdrawal of reactivity (Bishopet al., 2004; Sauer, Lynch, Walach, & Kohls, 2011).

The fact that we had to rely on a convenience sample might also help to explain why some of the effects appear to beweak, especially the prediction of error rates by self-reported mindfulness. It may well be that effects would show up ina sample of individuals highly proficient in mindfulness. However, at this stage the practical relevance of the effects is un-clear and more conclusive research utilizing more sophisticated experimental designs is clearly needed. We recommend not

1566 S. Sauer et al. / Consciousness and Cognition 20 (2011) 1558–1569

only paying particular attention to controlling for confounders, but we also specifically suggest explicitly controlling for theprevalent state of mindfulness in the experimental set-up by means of explicit verbal instruction and self-assessment.

With regard to controlling for confounders, it should be noted that the effects of mindfulness on RT were independent ofmotor capabilities, as age was controlled for as well as depression and anxiety. Our psychometric analyses suggest, in accor-dance with previous research, that the Freiburg Mindfulness Inventory is capable of distinguishing between individuals highand low in mindfulness. The results obtained in the four emotional response tests additionally not only corroborate thevalidity of self-reported mindfulness instruments, but actually suggest that the separation of mindfulness into the two sub-facets acceptance and presence is not only heuristically justifiable, but is important for experimental research. Using the gen-eric mindfulness score may blur results in behavioral paradigms where the two mindfulness facets have differential effects.

In sum, the results of the study only partially support the hypothesis that mindfulness is associated with less aversivereactions towards aversive stimuli. However, the fact that the two facets of mindfulness were differentially associated withthe four tested emotional reactions provides new evidence for the construct validity of mindfulness. A central finding of thisstudy is that two distinct subfacets of mindfulness, presence and acceptance can – at least to some degree – be disentangledin experimental design on the basis of measuring emotional behavior by means of explicit and implicit measures. Althoughour hypotheses were not supported for every behavioral test, the evidence of the differential mechanisms of mindfulness isstrong enough to warrant more consideration in future research.

A few limitations of the present study need to be borne in mind. A potential limitation is that we had to rely on an onlineconvenience sample and the data were collected via the internet. However, Gosling, Vazire, Srivastava, and John (2004) con-ducted a review on the quality of the online sampling approach and concluded that both online and traditional methodsyield similar results. Nevertheless, future studies should also collect data in traditional ways. As our sample population con-sisted of healthy non-clinical adults only, it can additionally be assumed that both individuals high and low in mindfulnesswere potentially not included in this population. It seems, therefore, encouraging that some of the expected effects werefound in our sample, given the fact that the variance of well-being and mindfulness parameter is normally found to be re-duced in such samples (and hence effects are smaller). However, future research should aim at recruiting clinical samples aswell as individuals highly proficient in mindfulness in order to substantiate possible effects. Secondly, as this study was con-ducted as a correlational study, the design naturally precludes strong causal conclusions. More sophisticated designs involv-ing longitudinal measurement and experimental manipulation of mindfulness are needed for more conclusive insights.Thirdly, a number of methodological factors may also have exerted some influence. For example, the emotional valenceof the words was assessed two times in total. Such multiple measurement may introduce method bias.

We did not manipulate individual mindfulness levels, i.e. we did not ask our participants to influence ‘‘state’’ mindfulness.It may therefore be argued that we have only measured ‘‘trait’’ mindfulness. Our data therefore only permit deriving resultsregarding the association of mindfulness with emotional behavior in general. Future studies should also measure mindful-ness as a ‘‘state’’ variable thus increasing internal validity of the design, for example by means of comparison of inter- andintrapersonal results obtained in mindful and normal states. In a design experimentally inducing state mindfulness, onecould expect group differences in emotional behavior tests to be stronger than the differences found between groups of par-ticipants who did not receive any mindfulness manipulation.

To conclude, the presence and acceptance facet of mindfulness play a differential role in emotional regulation, and morework on this relationship is needed to better understand the cognitive processes involved. Subsequent studies to test theassociation between mindfulness and emotional reactions should consider both explicit and implicit indicators with a focuson implicit indicators, as there is a relative lack of research here. Care should be taken that individual mindfulness levels arecontrolled. This could, for example, be achieved by employing a sample of individuals familiar with mindfulness practiceswho are asked to carry out a mindfulness exercise before the experiments (Arch & Craske, 2006). Furthermore, random groupallocation and longitudinal designs are essential for internal validity and conclusive insights.

Our approach of disentangling attentional and emotional subfacets of mindfulness, as well as employing both implicit andexplicit paradigms, is a promising way of improving the scientific quality of studies in this field. The evidence presented heresupports the claim that mindfulness exhibits effects on emotional behavior facing aversive stimuli. Furthermore, such effectsare not only subject to conscious and deliberate self-assessment, but also exhibit impact upon more basic implicit processesand hence are of relevance for practical and clinical situations.

Acknowledgments

Sebastian Sauer and Niko Kohls are supported by the Peter-Schilffarth-Institute for Sociotechnology, Bad Tölz, Germany.Harald Walach, Stefan Schmidt, Thilo Hinterberger, Majella Horan and Niko Kohls are supported by the Samueli Institute,Alexandria, USA. We are indebted to the anonymous reviewers who helped to substantially improve the manuscript.

Appendix A. Word stimuli

Pseudo-words:Grick, Gensch, Ozok, Salk, Selin, Lend, Soer, Difoko, Toch, Bulauf.Normal words:

S. Sauer et al. / Consciousness and Cognition 20 (2011) 1558–1569 1567

Linse, Haus, Kuh, Saft, Kamera, Arbeiter, Tuer, Grill, Fabrik, Brot (English translation: lens, house, cow, juice, camera, worker,door, grill, factory, bread).

Appendix B. Valence (mean and standard deviation) of selected aversive pictures from the International AffectivePictures System

Picture

ID Mean SD

Snake

1019 3.05 1.96 Snake 1050 3.46 2.15 Snake 1052 3.50 1.87 Snakes 1111 3.25 1.64 Spider 1201 3.55 1.88 Roaches 1274 3.17 1.53 Roaches 1275 3.30 1.65 Rat 1280 3.66 1.75 PitBull 1300 3.55 1.78 Toddler 2095 1.79 1.18 Hospital 2205 1.95 1.58 Sad Girls 2455 2.96 1.79 Hunters 2688 2.73 2.07 Dying Man 3230 2.02 1.30 Injured Child 3301 1.80 1.28 Attack 3500 2.21 1.34 Soldier 6212 2.19 1.49 Aimed Gun 6230 2.37 1.57 Aimed Gun 6243 2.33 1.49 Knife 6300 2.59 1.66 Distressed Fem 6311 2.58 1.56 Attack 6370 2.70 1.52 Police 6838 2.45 1.44 Roach On Pizza 7380 2.46 1.42 Seal 9180 2.99 1.61 Oil Fire 9230 3.89 1.58 Smoke 9280 2.80 1.54 Garbage 9290 2.88 1.52 Garbage 9340 2.41 1.48 Kids 9520 2.46 1.61

TOTAL

2.77 1.61

Notes. ID refers to the Number in the International Affective Pictures System. SD = standard deviation.

Appendix C. Valence (mean and standard deviation) of selected neutral pictures from the International AffectivePictures System

Picture

ID Mean SD

Twins

2890 4.95 1.09 Rolling pin 7000 5 0.84 Towel 7002 4.97 0.97 Spoon 7004 5.04 0.6 Bowl 7006 4.88 0.99 Mug 7009 4.93 1 Basket 7010 4.94 1.07 Fan 7020 4.97 1.04 Stool 7025 4.63 1.17

(continued on next page)

1568 S. Sauer et al. / Consciousness and Cognition 20 (2011) 1558–1569

Appendix C. (continued)

Picture

ID Mean SD

Iron

7030 4.69 1.04 Hammer 7034 4.95 0.87 Mug 7035 4.98 0.96 Baskets 7041 4.99 1.12 Clothes pins 7052 5.33 1.32 Light bulb 7055 4.9 0.64 Tool 7056 5.07 1.02 Coffee cup 7057 5.35 1.37 Fork 7080 5.27 1.09 Umbrella 7150 4.72 1 Fabric 7160 5.02 1.1 Pole 7161 4.98 1.02 Abstract art 7185 4.97 0.87 Clock 7211 4.81 1.78 Chair 7235 4.96 1.18 Fish 7484 4.99 1.97 Abstract art 7186 4.63 1.6 Tissue 7950 4.94 1.21

TOTAL

4.96 1.11

Notes. ID refers to the Number in the International Affective Pictures System. SD = standard deviation.

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