Mindfulness and acceptance in relation to Behavioral Inhibition System sensitivity and psychological distress

Personality and Individual Differences 72 (2015) 24–29

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Mindfulness and acceptance in relation to Behavioral Inhibition System sensitivity and psychological distress Timothy S. Hamill, Scott M. Pickett ⇑, Hayley M. Amsbaugh, Kristin M. Aho Oakland University, Rochester, MI, United States

a r t i c l e

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Article history: Received 8 February 2014 Received in revised form 31 July 2014 Accepted 7 August 2014 Available online 14 September 2014 Keywords: Behavioral Inhibition System Mindfulness Acceptance Psychological distress Emotion regulation

a b s t r a c t The current study examined whether two adaptive emotion regulation strategies, mindfulness and acceptance, moderate the relationship between Behavioral Inhibition System sensitivity and psychological distress. Participants were 467 students at a large Midwestern university. Data were collected with paper-and-pencil questionnaires and analyzed using hierarchical multiple regression analyses. A significant positive association was observed between Behavioral Inhibition System sensitivity and psychological distress, with acceptance and mindfulness facets (Nonreactivity and Observing) significantly moderating this association. Findings suggest mindfulness- and acceptance-based strategies may buffer the influence of Behavioral Inhibition System sensitivity on the development and maintenance of psychological distress in nonclinical populations. Ó 2014 Elsevier Ltd. All rights reserved.

1. Introduction Research on the relationship between emotion regulation (ER), temperamental vulnerabilities (e.g., Behavioral Inhibition System [BIS] sensitivity), and symptoms of psychopathology has focused on maladaptive ER strategies (e.g., Pickett, Bardeen, & Orcutt, 2011). However, the influence of adaptive ER strategies may be equally important. Adaptive ER strategies such as mindfulness and acceptance may reduce negative affect associated with psychological symptoms by modifying an individual’s response to heightened emotional reactivity associated with BIS sensitivity. The current study examined mindfulness and acceptance as potential moderators in the relationship between BIS sensitivity and psychological distress. 1.1. BIS and psychological distress The revised Reinforcement Sensitivity Theory (rRST; Corr, 2008; Gray & McNaughton, 2000) posits that three interconnected Abbreviations: AAQ-II, Acceptance and Avoidance Questionnaire-II; ACT, acceptance and commitment therapy; BAS, Behavioral Activation System; BIS, Behavioral Inhibition System; DASS, Depression Anxiety and Stress Scales; ER, emotion regulation; FFMQ, Five Facet Mindfulness Questionnaire; FFFFS, Fight–Flight–Freeze System; MBCT, mindfulness-based cognitive therapy; MBSR, mindfulness-based stress reduction; rRST, revised Reinforcement Sensitivity Theory. ⇑ Corresponding author. Address: Oakland University, Department of Psychology, 209 Pryale Hall, 2200 N. Squirrel Rd., Rochester, MI 48309, United States. Tel.: +1 (248) 370 2307; fax: +1 (248) 370 4612. E-mail address: [email protected] (S.M. Pickett). http://dx.doi.org/10.1016/j.paid.2014.08.007 0191-8869/Ó 2014 Elsevier Ltd. All rights reserved.

motivational systems impact individual differences in temperament and emotional responding; BIS balances activation of the Behavioral Activation System (BAS) toward rewarding stimuli with activation of the Fight–Flight–Freeze System (FFFS) toward threatening stimuli and perceived punishment. Conflict between BAS and FFFS activates BIS and produces anxiety and arousal, possibly inhibiting behavioral responses and reducing personal risk. Anxiety and arousal levels depend on the degree of conflict between systems or BIS sensitivity. Increased BIS sensitivity may cause greater anxiety and arousal and increase avoidant behaviors. Increased BIS sensitivity has been linked to psychopathology, specifically anxiety and depressive disorders including generalized anxiety disorder (Maack, Tull, & Gratz, 2012), social anxiety disorder (Kimbrel, Nelson-Gray, & Mitchell, 2012), posttraumatic stress disorder symptoms (Pickett et al., 2011), and major depression symptoms and depressive moods (Pinto-Meza et al., 2006). Heightened BIS sensitivity may increase feelings of anxiety and fear resulting in an increase in avoidance motivations, driving maladaptive ER while adaptive ER, such as mindfulness and acceptance, may reduce these experiences (Gratz & Tull, 2010).

1.2. Mindfulness and acceptance Mindfulness and acceptance focus on maintaining active awareness of present events and feelings while remaining nonjudgmental and nonreactive (Baer, Smith, Hopkins, Krietemeyer, & Toney, 2006). Engaging in mindful and accepting behaviors may enhance psychological flexibility (Hayes, Luoma, Bond,

T.S. Hamill et al. / Personality and Individual Differences 72 (2015) 24–29

Masuda, & Lillis, 2006). Coupled with increased awareness and insight, greater psychological flexibility allows individuals to direct behaviors toward increasing long-term life quality (Hayes, Wilson, Gifford, Follette, & Strosahl, 1996; Hayes et al., 2006). Therefore, mindfulness and acceptance may reduce the emotional reactivity associated with BIS sensitivity and increase positive emotional experience. Research has examined the efficacy of mindfulness- and acceptance-based treatment programs (see Baer, 2003; Kabat-Zinn, 1990; Segal, Williams, & Teasdale, 2002; and Hayes, Strosahl, & Wilson, 1999), in reducing BIS-related psychological distress. These programs include mindfulness exercises (e.g., breathing and meditative exercises) that may increase acceptance of unwanted emotions and experiences, resulting in behavioral changes that decrease distress (Forman, Herbert, Moitra, Yeomans, & Geller, 2007). Specifically, mindfulness-based stress reduction (MBSR) decreases levels of anxiety, depression, and stress from pre- to post-treatment (Goldin & Gross, 2010; Kabat-Zinn et al., 1992; Marchand, 2012) and promotes long-term maintenance of reductions (Miller, Flietcher, & Kabat-Zinn, 1995). Decreased psychological distress is an outcome associated mindfulness-based cognitive therapy (MBCT; e.g., Marchand, 2012) and acceptance and commitment therapy (ACT; e.g., Forman et al., 2012). Researchers suggest that behavioral activation fosters mindfulness and counteracts increased behavioral inhibition associated with psychopathology (Evans et al., 2008). 1.3. BIS, mindfulness, and acceptance Limited research has investigated mindfulness and acceptance related to BIS sensitivity and psychological distress. Recently, mindfulness and well-being were negatively related to BIS sensitivity and mindfulness was positively related to well-being (Sauer, Walach, & Kohls, 2011). BIS sensitivity mediated the relationship between mindfulness and well-being (Sauer et al., 2011). Further, lower BIS-sensitivity and higher mindfulness and well-being were observed for meditation practitioners compared to non-practitioners. An interpretation of the results focused on using mindfulness to reduce BIS sensitivity; however, this assumption was not directly examined. This interpretation may be problematic because BIS sensitivity may be a stable trait minimally influenced by the environment (Takahashi et al., 2007). A model accounting for the moderating role of emotion regulation may improve our understanding of the relationship between BIS sensitivity and psychological distress. If BIS sensitivity is stable, ER strategies may moderate the associated emotional outcomes instead of merely explaining the relationship (Bijttebier, Beck, Claes, & Vandereycken, 2009). However, the influence of mindfulness and acceptance on BIS sensitivity and the relationship between BIS sensitivity and psychological outcomes has not been investigated. Therefore, the aim of the current study was to examine the relationship between BIS sensitivity, mindfulness and acceptance, and psychological distress.

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well-being. Therefore, it was hypothesized that mindfulness and acceptance would instead moderate the association between BIS sensitivity and psychological distress. Such findings would suggest that mindfulness and acceptance buffer the negative effects of BIS sensitivity associated with psychological distress.

2. Methods and materials 2.1. Participants Data were collected from 467 college students (77.3% Female) who received partial research credit at a large Midwestern university. Most participants identified as White (78.6%), and others identified as Black/African American (11.2%), Asian (3.2%), American Indian Alaska Native, Native Hawaiian or other Pacific Islander (0.6%), and Other (6.4%). Additionally, 2.9% identified their ethnicity as Hispanic or Latino. Item responses were missing for 20% of the cases. Maximum-likelihood estimation was used to account for the subsequent missing subscale scores (1.6% of the total data were replaced).

2.2. Procedure Participants were recruited from the psychology department subject pool. Data were collected in sessions of 18 or less participants. After the informed consent process, participants completed a series of paper-and-pencil questionnaires. Upon completion, participants were debriefed and granted research credit. Participation requirements were fluency in English and a minimum age of 18 years.

2.3. Measures 2.3.1. Covariates Sex, age, and race were evaluated as covariates in the analyses. Sex was dummy coded as Sex (% Female) = Male (0) and Female (1). Race was dummy coded as two variables, Race (% White) = White (1) and not White (0) and Race (% Black) = Black (1) and not Black (0).

2.3.2. BIS/BAS scale The BIS/BAS Scales (Carver & White, 1994) were used to assess BIS and BAS sensitivity. Participants rated 20 items on a 4-point Likert scale (1 = very true for me, 4 = very false for me). A total score was calculated by summing the BIS sensitivity items. Sum scores were also calculated for each of the BAS subscales (i.e., Reward Responsiveness, Fun Seeking, and Drive. The BIS/BAS Scales have adequate psychometric properties (Carver & White, 1994). Internal consistencies (i.e., alpha coefficients) for the BIS/ BAS Scales were sufficient and are presented in Table 1.

1.4. Aims and hypotheses The current study examined the influence of mindfulness and acceptance on the relationship between BIS sensitivity and psychological distress. Since BIS sensitivity is associated with negative psychological outcomes (e.g., Maack et al., 2012), it was first hypothesized that BIS sensitivity would be positively associated with psychological distress. Consistent with previous research (Marchand, 2012), it was also hypothesized that mindfulness and acceptance would be negatively associated with BIS sensitivity and psychological distress. Further, the stable nature of BIS sensitivity (Takahashi et al., 2007) contradicts the proposition that BIS sensitivity mediates the relationship between mindfulness and

2.3.3. Acceptance and Action Questionnaire-II The Acceptance and Action Questionnaire-II (AAQ-II; Bond et al., 2011), a 7-item self-report measure of psychological flexibility, was used to assess acceptance to experiencing negatively perceived private events (i.e., cognitions, memories). Participants rated each item on a 7-point Likert scale (1 = never true, 7 = always true). Responses were reversed scored and summed for a total score of Acceptance. The AAQ-II demonstrated adequate psychometric properties across seven samples (n = 3280; Bond et al., 2011). Internal consistency (i.e., alpha coefficient) was excellent for the AAQ-II and is presented in Table 1.

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T.S. Hamill et al. / Personality and Individual Differences 72 (2015) 24–29

Table 1 Bivariate correlations, means, and standard deviations for study variables (N = 467). Variables

1

2

3

4

1. Sex (% Female) – 2. Race (% White) .04 – 3. Race (% Black) .10* .67** – 4. Age .05 .03 .04 – 5. DASS – Depression .01 .06 .07 .06 6. DASS – Anxiety .03 .00 .05 .07 7. DASS – Stress .06 .03 .07 .09* 8. BIS sensitivity .24** .05 .09* .14** 9. BAS – Reward Responsiveness .05 .01 .00 .09 10. BAS – Fun Seeking .01 .04 .03 .09* 11. BAS – Drive .05 .05 .08 .01 12. Acceptance .08 .01 .06 .05 13. Observing .01 .12* .06 .05 14. Describing .03 .01 .05 .11* 15. Acting with awareness .03 .08 .08 .06 16. Nonjudging .07 .08 .00 .06 ** 17. Non reactivity .17 .05 .02 .17** Mean Standard deviation

.77

.79

.11 20.99 4.92

5

6

.87 .67** .70** .35** .00 .04 .02 .60** .08 .16** .41** .38** .25** 3.72 3.94

7

.75 .70** .35** .13** .09 .06 .49** .20** .11* .40** .38** .21** 4.01 3.66

8

.84 .43** .22** .01* .11* .54** .09* .13** .48** .43** .31** 6.05 4.37

9

.79 .23** .02 .03 .48** .11* .24** .36** .38** .28** 20.73 3.94

10

.67 .47** .64** .01 .25** .16** .07 .07 .02 16.95 2.19

11

.70 .47** .02 .12* .03 .21** .01 .01 12.22 2.36

.69 .07 .09 .15** .02 .01 .04 11.36 2.44

12

13

.91 .06 .32** .46** .55** .33** 36.89 8.93

14

.77 .24** .09 .23** .33** 25.48 5.72

15

.90 .30** .24** .31** 28.18 6.33

16

.87 .44** .16** 28.01 5.96

.90 .08

17

.76

28.14 21.18 6.70 4.49

Note: Coefficient alphas (where appropriate) are on the diagonal in bold. * p < 05. ** p < 001.

2.3.4. Five Facet Mindfulness Questionnaire The Five Facet Mindfulness Questionnaire (FFMQ; Baer et al., 2006) was used to assess five facets of mindfulness (i.e., Observing, Describing, Acting with awareness, Nonjudging, and Nonreactivity) using a 39-item self-report questionnaire. Participants responded on a 5-point Likert scale (1 = never or rarely true, 5 = very often or always true). The FFMQ, which consists of items from other measures of mindfulness, has demonstrated adequate psychometric properties (Baer et al., 2006). Internal consistencies (i.e., alpha coefficient) were adequate for each facet and are presented in Table 1. 2.3.5. Depression, Anxiety, and Stress Scales The Depression, Anxiety, and Stress Scales (DASS; Lovibond & Lovibond, 1995) was used to assess symptoms of depression, anxiety, and stress, which are used in the current study to define psychological distress. Participants indicated the degree (i.e., frequency/ severity) to which they had experienced 21 symptoms over the past week using a 4-point Likert scale (0 = did not apply to me at all, 3 = applied to me very much, or most of the time). The subscale scores were calculated by summing the responses for the 7 items comprising each subscale. The DASS demonstrates adequate psychometric properties, including the capacity to distinguish between the three emotional states characterized by the subscales (Lovibond & Lovibond, 1995). Internal consistency (i.e., alpha coefficient) for each subscale was sufficient and is presented in Table 1. 3. Results 3.1. Preliminary analysis The relationships between covariates and variables of interest were examined (Table 1). Sex, Age, and Race (% Black) were all significantly related to an outcome variable or a potential moderator and were therefore included in the subsequent analyses. DASS subscales and BIS sensitivity were associated positively, and DASS subscales were associated negatively with Acceptance and four mindfulness facets (Describing, Acting with awareness, Nonjudging, and Nonreactivity). Further, BIS sensitivity was associated negatively with Acceptance and the same four mindfulness facets. Acceptance was associated positively with four mindfulness facets (Describing, Acting with awareness, Nonjudging, and

Nonreactivity). Unexpectedly, Observing was associated positively with the DASS Anxiety and Stress subscales and BIS sensitivity. Observing was negatively associated with Nonjudging but positively associated with Describing and Nonreactivity. 3.2. Hierarchical multiple regression analyses Hierarchical multiple regression analyses assessed our hypotheses. In the each analysis, Sex (% Female), Race (% Black) and Age were entered into the first step of the model. The three BAS subscales were entered into the second step. BIS sensitivity was entered into the third step. Acceptance and mindfulness facets and interaction terms were entered into the fourth and fifth steps, respectively. In the analysis predicting DASS – Depression, there was a significant main effect of BIS sensitivity in step three (Table 2). In step four, significant main effects were found for Acceptance, Describing, Acting with awareness, and Nonreactivity. In step five, only the BIS  Acceptance interaction remained significant. Simple slopes analysis (Aiken & West, 1991) revealed a significant positive association between BIS sensitivity and DASS – Depression for participants low in Acceptance (Fig. 1). In the analysis predicting DASS – Anxiety, there was a significant main effect of BAS – Reward Responsiveness in step two (Table 2). In step three, there was a significant main effect of BIS sensitivity. In step four, there were significant main effects of Acceptance, Observing, Acting with awareness, and Nonreactivity. There were two significant interaction terms in step five: BIS  Acceptance and BIS  Observing. Simple slopes analysis (Aiken & West, 1991) revealed a significant positive association between BIS sensitivity and DASS – Anxiety for participants high in Observing (Fig. 2) and for participants low in Acceptance (Fig. 3). In the analysis predicting DASS – Stress, there was a significant main effect of Age In step one (Table 2). In step two, there was a significant main effect of BAS – Reward Responsiveness. In step three, there was a significant main effect of BIS sensitivity. In step four, there were significant main effects of Acceptance, Describing, Acting with awareness, Nonjudging, and Nonreactivity. In the final step, the BIS  Nonreactivity interaction was a significant predictor. Simple slopes analyses (Aiken & West, 1991) revealed a significant positive association between BIS sensitivity and DASS – Stress for participants low in Nonreactivity (Fig. 4).

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T.S. Hamill et al. / Personality and Individual Differences 72 (2015) 24–29 Table 2 Hierarchical multiple regression analyses predicting DASS subscale scores. Predictors

DASS – Depression

DASS – Anxiety 2

t

b

DR

Step 1 Sex (% Female) Race (% Black) Age

.01 .01 .07 .06

.06 .98 .54

.41

8.49***

.47 .04 .11 .16 .04 .09

8.98*** .90 2.39* 3.44* .77 2.01*

.15 .05 .00 .01 .01 .06

2.73** 1.12 .06 .24 .22 1.39

.14***

Step 3 BIS sensitivity

.25***

Step 4 Acceptance Observing Describing Acting with awareness Nonjudging Nonreactivity

.03***

Step 5 BIS  Acceptance BIS  Observing BIS  Describing BIS  Acting with awareness BIS  Nonjudging BIS  Nonreactivity

DR

Step 1

.01 .03 .05 .07

.00 .00 .04 .03

t

b

.02 1.59 1.30

Step 2 BAS – Reward Responsiveness BAS – Fun Seeking BAS – Drive

DASS – Stress 2

.02* .14 .03 .03

2.24* .55 .64

.38

7.82***

.31 .15 .08 .18 .07 .14

5.67*** 3.27** 1.84 3.81*** 1.43 2.91**

.11 .10 .01 .02 .04 .06

1.97* 2.11* .25 .42 .78 1.32

.12***

Step 3

.20***

Step 4

.03***

Step 5

t

.07 .08 .09

1.43 1.64 1.96*

.22 .01 .02

3.45* .14 .27

.43

9.18***

.30 .01 .12 .26 .11 .17

5.87*** .25 2.85** 5.87*** 2.34* 3.85***

.07 .02 .01 .07 .00 .10

1.48 .58 .10 1.55 .05 2.37*

DR2 .02*

Step 1

.70 .99 1.58

Step 2

b

.04***

Step 2

.15***

Step 3

.24***

Step 4

.03***

Step 5

Note: N = 467. * p < 05. ** p < 01. *** p < 001.

Fig. 1. Interaction effect of BIS sensitivity and acceptance predicting DASS Depression scores.

Fig. 2. Interaction effect of BIS sensitivity and observing in predicting DASS Anxiety scores.

4. Discussion The current study examined the relationship between BIS sensitivity, adaptive ER, and psychological distress. An interactive model was examined because adaptive ER may modulate the trait-like effects of BIS sensitivity (Takahashi et al., 2007) on psychological outcomes (Bijttebier et al., 2009). Acceptance and

Fig. 3. Interaction effect of BIS sensitivity and acceptance in predicting DASS Anxiety scores.

Fig. 4. Interaction effect of BIS sensitivity and non reactivity in predicting DASS Stress scores.

mindfulness were hypothesized to moderate (i.e., buffer) the effects of BIS sensitivity on psychological distress. Results partially support our hypotheses and support previous research (e.g., Bijttebier et al., 2009) suggesting heightened BIS sensitivity is related to greater psychological distress. Findings also indicate that heightened BIS sensitivity and psychological distress were negatively associated with Acceptance and four mindfulness facets (Describing, Acting with awareness, Nonjudging, and

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Nonreactivity), also supporting previous research (e.g., Evans et al., 2008). Further, Acceptance and certain mindfulness facets moderated the relationship between BIS sensitivity and psychological distress, low Acceptance influenced the association between heightened BIS sensitivity and depression symptoms, BIS sensitivity and anxiety symptoms and low Nonreactivity influenced the association between heightened BIS sensitivity and stress symptoms. Findings yielded unexpected results regarding Observing, which was associated with higher emotional reactivity and psychological distress. Findings suggest that Observing moderates the relationship between BIS sensitivity and anxiety symptoms; participants reporting heightened BIS sensitivity reported greater anxiety symptoms when Observing was high. However, the association was not found for participants reporting low Observing, suggesting observing and attending to sensations, thoughts, and emotions may be problematic when emotional reactivity is heightened. Acceptance may buffer the relationship between negative emotion and depression symptoms. Findings support that acceptance may diminish use of maladaptive ER associated with depression, including rumination (Liverant, Kamholz, Sloan, & Brown, 2011). Rumination, which is associated with experiential avoidance (conceptually the opposite of acceptance), is the focus on negative emotions and the avoidance of events resulting in compounded emotional distress (e.g., Cribb, Moulds, & Carter, 2006). Rumination is also related to BIS sensitivity (Keune, Bostanov, Kotchoubey, & Hautzinger, 2012) and decreased acceptance (Liverant et al., 2011). According to the current model, unregulated BIS sensitivity may increase depression symptoms through the inflated evaluation of negative emotion as threatening or overly negative. Past research suggests that preoccupation with negative emotions without effective coping strategies may increase feelings of depression (Lam, Smith, Checkley, Rijsdik, & Sham, 2003). Based on current findings, increased use of acceptance-based strategies may function as a healthy ER alternative to rumination. Contrary to rumination, acceptance may create cognitive and emotional distance from negative emotions by adopting a non-judgmental perspective, thus buffering the observed influence of heightened BIS sensitivity on depression. Acceptance was also found to buffer the influence of BIS sensitivity on anxiety symptoms. This finding supports theoretical work suggesting that heightened BIS sensitivity may result in stronger anxiety reactions (Corr, 2008; Gray & McNaughton, 2000). Further, previous research has suggested that heightened BIS sensitivity in conjunction with an unwillingness to experience negative emotions (i.e., non-acceptance) may contribute to increased anxiety reactions (Pickett et al., 2011). The unwillingness to experience the increased emotional reactivity associated with heightened BIS sensitivity may paradoxically increase the emotional reactivity (i.e., anxiety symptoms; Wenzlaff & Wegner, 2000), thus providing a context for the interpretation of the current findings. Unexpectedly, findings suggest increased Observing strengthens the relationship between heightened BIS sensitivity and anxiety symptoms. Baer et al. (2006) suggest that Observing may only be understood as adaptive through experience with mindfulness-based practices, which may highlight a measurement issue. Although lack of meditation exposure may influence Observing responses, it was not measured and generalizations cannot be made. Baer et al. (2006) also suggest that Observing-related questions may not effectively measure for mindfulness due to heavy focus on the impact of external stimuli on internal experience. Future research should investigate whether Observing measures yield universally different results between practitioners and nonpractitioners of meditation. Additionally, Observing-based measures of mindfulness may unintentionally focus on negative ER; some studies have found a positive relationship between Observing and anxiety symptoms

(Luberto, McLeish, Zvolensky, & Baer, 2011). As Observing focuses on attention to both internal sensations and external stimuli, higher scores may represent maladaptive behaviors. Previous research demonstrates that hypervigilant behaviors are positively related to anxiety symptoms (Mogg, Bradley, De Bono, & Painter, 1997). According to the vigilant-avoidance hypothesis, hypervigilance often leads to avoidance of perceived threatening stimuli/ contexts, preventing habituation and maintaining anxiety (Mogg et al., 1997). From an Observing-hypervigilance perspective, results support previous research indicating ER modulation between BIS sensitivity and anxiety symptoms (e.g., Pickett, Lodis, Parkhill, & Orcutt, 2012). Future studies should continue to investigate the possible role of Observing in problematic mechanisms such as hypervigilance in non-meditation practitioners. Lastly, findings suggest that mindfulness may buffer the influence of BIS sensitivity on stress. Previous research suggests a negative association between BIS sensitivity and Nonreactivity (LeenFeldner, Zvolensky, Feldner, & Lejuez, 2004). In previous research, Nonreactivity buffered the relationship between stress levels and overall psychological health (Bränström, Duncan, & Moskowitz, 2011), highlighting the importance of mindfulness in the relationship between BIS sensitivity and negative psychological outcomes. Adaptive ER strategies, such as Nonreactivity, may allow an individual to disengage from heightened emotional reactivity and reduce feelings of stress. This corresponds with MBSR aims to increase situational attentiveness (Goldin & Gross, 2010) and reduce habitual emotional reactivity (Ramel, Goldin, Carmona, & McQuaid, 2004).

4.1. Limitations The current study is not without limitations. The correlation, cross-sectional survey design precludes causal conclusions. Future studies should implement experimental designs that involve mindfulness- and/or acceptance-based treatments to investigate causation. This study examined a college-aged, non-clinical, and predominately White sample. Future research should investigate the current hypotheses in more diverse, clinical, and meditation savvy samples for improved interpretation and generalizability of findings. Further, competing mediation models should be examined to clarify the directionality of the relationships. Despite limitations, current findings provide insights into complex relationships between mindfulness, acceptance and psychological distress.

5. Conclusions Although previous studies have examined the association between BIS sensitivity, mindfulness and acceptance, and psychological distress, the current study is the first to suggest that mindfulness and acceptance moderates the relationship between heightened BIS sensitivity and psychological distress symptoms. The current model suggests acceptance- and mindfulness-based practice for individuals predisposed to heightened BIS sensitivity to decrease the likelihood of developing or maintaining psychological distress. Current findings suggest that Acceptance and Nonreactivity buffer BIS sensitivity’s influence on psychological distress and provide peripheral support for the effectiveness of such approaches as ACT (Hayes, Strosahl, & Wilson, 1999) and MBCT (Segal, Williams, & Teasdale, 2002) on long-term maintenance of decreased BIS-related psychopathology (Evans et al., 2008; Forman et al., 2007). However, future studies should examine if therapeutic techniques that focus on emotional change or regulation can reduce such vulnerabilities if BIS sensitivity is truly a stable characteristic.

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