نقش توجه اجرایی در خودآسیبی عمدی

bstract Although a wealth of literature has examined the role of emotion-related factors in deliberate self-harm (DSH), less is known about neurocognitive factors and DSH. In particular, despite theoretical literature suggesting that deficits in executive attention may contribute to engagement in DSH, studies have not yet examined the functioning of this attentional network among individuals with DSH. The present study sought to address this gap in the literature by examining the functioning of the alerting, orienting, and executive attentional networks among participants with a recent history of DSH (n=15), a past history of DSH (n=18), and no history of DSH (n=21). Controlling for borderline personality pathology and depression symptoms, participants with a recent history of DSH exhibited deficits in executive attention functioning relative to participants without any history of DSH. No differences were found in terms of performance on the alerting or orienting attentional networks. These results provide preliminary support for the association between executive attention deficits and DSH.

1. Introduction The past decade has heralded an increase in research examining the factors contributing to deliberate self-harm (DSH; also referred to as non-suicidal self-injury), defined here as the deliberate, direct destruction of body tissue without conscious suicidal intent (see Gratz, 2001 and Klonsky et al., 2003). Although historically studied in the context of psychopathology (e.g., borderline personality disorder [BPD]; American Psychiatric Association, 2000), growing evidence indicates high rates of DSH in nonclinical populations as well (e.g., 15–44%; Ross and Heath, 2002, Gratz, 2006, Gratz et al., 2010, Toprak et al., 2011 and Cerutti et al., 2012). Indeed, similar to findings obtained within clinical samples, DSH has been found to be associated with a wide range of negative outcomes among nonclinical populations, including (a) emotional distress and poor coping abilities (Hasking et al., 2008); (b) relationship dissatisfaction and substance use (Toprak et al., 2011); and (c) heightened risk for suicide attempts (Nock et al., 2006). Despite the clinical relevance and public health significance of DSH within nonclinical populations, limited research has examined the mechanisms underlying DSH within this population. Moreover, the limited studies that have been conducted in this area have focused almost exclusively on emotion-related factors (e.g., emotion dysregulation, Paivio and McCulloch, 2004, Gratz and Roemer, 2008 and Gratz et al., 2010) to the neglect of other potentially relevant mechanisms, such as neurocognitive factors. One set of factors that may be particularly important to examine in this regard is attentional network functioning, which is considered essential to psychological well-being and theorized to be the gatekeeper of emotion regulation (Bardeen and Read, 2010 and Gross and Thompson, 2011). Specifically, due to its role in guiding attentional engagement and disengagement from emotionally-salient stimuli, attentional network functioning can be seen as a crucial first step in emotion modulation. According to Fan et al., 2002, the attention system comprises three distinct attentional networks. The alerting attentional network involves the ability to sustain an alert state. The orienting attentional network involves the ability to identify and select visual stimuli. Finally, the executive attentional network serves to oversee and resolve conflict between other attentional networks, involving the facilitation and inhibition of activation in other networks ( Botwinick et al., 2001). Theoretical and empirical literature suggest that engagement in DSH may be associated with deficits in executive attention functioning in particular (e.g., Linehan, 1993 and Posner et al., 2002). The executive attentional network is thought to underlie self-regulatory efforts (see Rothbart et al., 2007), and researchers have theorized that dysfunction in attentional regulation may play an important role in the emotion dysregulation evident among individuals with borderline personality disorder (BPD) and recurrent DSH ( Linehan, 1993). Specifically, when individuals who engage in DSH come into contact with aversive emotional experiences or other cues for DSH, deficits in executive attention may lead to difficulties in disengaging attention from such cues, as well as difficulties attending to alternative stimuli. Consequently, with continued exposure to these cues, emotional arousal may increase, resulting in heightened emotion dysregulation and greater difficulties inhibiting maladaptive behaviors, such as DSH (see also Abdullaev et al. (2010), who describe a similar process with regard to substance abuse). Although no studies to date have examined the association between DSH and attentional network functioning in general or executive attention in particular, preliminary research provides some support for the relevance of deficits in other indices of executive functioning to DSH. For example, results of a recent study revealed information processing deficits among university students with a history of repeated DSH, relative to individuals with no history of DSH and low emotion dysregulation (Franklin et al., 2010). Likewise, in a study comparing adolescents with DSH to healthy controls, those with a history of severe DSH were found to evidence working memory deficits, whereas those with a history of less severe DSH were found to evidence deficits in inhibitory control (Fikke et al., 2011). Finally, deficits in the executive attentional network have been found among patients with psychiatric disorders that commonly co-occur with DSH, including BPD (Haw et al., 2001) and posttraumatic stress disorder (PTSD; Zlotnick et al., 1999). For instance, research has provided evidence of executive attention deficits among both patients with PTSD (compared to controls with and without trauma-exposure; Leskin and White, 2007) and individuals with BPD (compared to non-personality disorder controls with low negative affect; Posner et al., 2002). Moreover, deficits in the functioning of the orienting and executive attentional networks have been found to predict BPD pathology (Fertuck et al., 2005). Together, the results of these studies suggest that deficits in the functioning of the executive attentional network may be associated with engagement in repeated DSH and highlight the need for research examining the role of executive attention in DSH. To this end, the current study used a laboratory-based measure of attentional functioning (i.e., the Attention Network Task; Fan et al., 2002) to examine differences in three dimensions of attentional functioning (i.e., the alerting, orienting, and executive attentional networks) among individuals with (a) current (i.e., past six months) repeated DSH; (b) past repeated DSH; and (c) no history of DSH. In particular, the unique association between attentional network functioning and DSH, above and beyond their shared association with relevant psychopathology (e.g., BPD), was examined. It was hypothesized that, relative to participants without a history of DSH, participants with current DSH would demonstrate worse executive attentional functioning. Given the lack of research on differences between individuals with current versus past DSH, as well as the relative paucity of literature on the emotional and cognitive functioning of individuals with only past DSH, no a priori hypotheses were made with regard to the attentional network functioning of individuals with past DSH only.

3. Results 3.1. Preliminary analyses All variables of interest fell within the acceptable range of normality. Means and standard deviations of the outcome variables are presented in Table 1. Of note, the current-DSH and past-DSH groups did not differ significantly in lifetime frequency of DSH, t (31)=1.35, P=0.19. The median lifetime frequency of DSH in the current-DSH group was 15 (ranging from 2 to 200 episodes of DSH, S.D.=59.38), whereas the median lifetime frequency of DSH in the past-DSH group was 10.50 (ranging from 3 to 106 episodes of DSH, S.D.=26.50). The most commonly endorsed method of DSH in the past-DSH group was cutting oneself (61%), followed by scratching oneself (33%) and carving pictures, designs (33%), or words into one׳s skin (33%). In the current-DSH group, the most commonly endorsed method of DSH was scratching oneself (53%), followed by cutting oneself (47%) and burning oneself with a lighter or match (33%). Table 1. Univariate analyses of covariance examining the effects of DSH group status on attentional network functioning. Current-DSH (n=15) M (S.D.) Past-DSH (n=18) M (S.D.) No-DSH (n=21) M (S.D.) F (2, 49) (ηp2) ANT alerting 35.40 (19.12) 28.11 (24.54) 39.52 (32.26) 0.46 (0.02) ANT orienting 32.40 (19.91) 32.28 (29.83) 38.95 (19.25) 0.01 (0.00) ANT executive 0.27 (0.06) 0.23 (0.09) 0.21 (0.05) 6.48⁎⁎ (0.21) ANT RT (msec) No cue—neutral 523.53 (72.10) 529.47 (75.33) 545.80 (69.77) No cue—congruent 564.60 (82.18) 579.59 (98.22) 603.50 (97.39) No cue—incongruent 680.40 (103.72) 696.06 (115.17) 729.15 (109.23) Center cue—neutral 472.40 (61.31) 479.12 (65.19) 504.40 (89.43) Center cue—congruent 513.60 (77.94) 547.76 (102.61) 573.75 (103.30) Center cue—incongruent 638.93 (209.55) 703.06 (124.20) 709.80 (114.01) Spatial cue—neutral 452.00 (65.65) 461.65 (73.43) 484.10 (85.74) Spatial cue—congruent 493.87 (77.23) 528.24 (105.72) 528.60 (96.10) Spatial cue—incongruent 624.93 (119.79) 653.94 (120.73) 640.05 (94.14) Double cue—neutral 462.53 (54.76) 474.94 (67.76) 499.70 (79.19) Double cue—congruent 515.33 (76.25) 543.65 (98.01) 571.00 (100.28) Double cue—incongruent 638.13 (216.19) 689.00 (108.06) 714.10 (104.87) Note. Means presented are non-adjusted means. Regarding tests of significance, borderline personality pathology and depression symptoms were included as covariates. In analyses involving the orienting attentional network, race/ethnicity was also included as a covariate. DSH=Deliberate self-harm; ANT=Attention Network Task; and RT=Reaction Time. ⁎P<0.05. ⁎⁎ P<0.01. Table options The current-DSH, past-DSH, and no-DSH groups were comparable in terms of age, F (2, 51)=0.20, P=0.82, gender, χ2 (2)=0.78, P=0.68, and racial/ethnic background, χ2 (2)=5.76, P=0.06. However, results revealed significant between-group differences in both BPD pathology and depression symptoms, F׳s (2, 51)≥10.07, P׳s<0.001. Specifically, although the current-DSH and past-DSH groups did not differ significantly in BPD pathology, P=0.93, or depression symptoms, P=0.17, both DSH groups reported greater BPD pathology than the no-DSH control group (P׳s<0.01) and the past-DSH group reported greater depression symptoms than the no-DSH control group (P<0.001). Thus, both BPD pathology and depression symptoms were included as covariates in primary analyses to establish the unique associations between DSH and attentional network functioning. Results revealed no significant associations between the demographic and clinical characteristics of interest and our dependent variables, with one exception: White participants evidenced better functioning of the orienting attention network than participants of other racial/ethnic backgrounds, t (52)=2.08, P=0.04. Thus, the dichotomous race/ethnicity variable was included as a covariate in analyses of orienting attention. 3.2. Primary analyses Results of the ANCOVAs examining between group differences in attentional network functioning revealed no significant between group differences on alerting attention or orienting attention (Table 1). Consistent with hypotheses, however, results did reveal significance between group differences (associated with a large effect size) in executive attentional functioning (Table 1). Follow-up Bonferonni-corrected pairwise comparisons revealed that participants in the current-DSH group evidenced significantly higher scores on executive attention than participants in the no-DSH group (P<0.01), suggesting poorer executive attention among participants with current (vs. no) DSH. There were no significant differences in executive attentional functioning between the past-DSH group and either the current-DSH group, P=0.24, or the non-DSH group, P=0.19. 1, 2