واکنش عاطفی و مقررات در کودکان سن پیش دبستانی که لکنت زبان دارند

Purpose. This study experimentally investigated behavioral correlates of emotional reactivity and emotion regulation and their relation to speech (dis)fluency in preschool-age children who do (CWS) and do not (CWNS) stutter during emotion-eliciting conditions. Method. Participants (18 CWS, 14 boys; 18 CWNS, 14 boys) completed two experimental tasks (1) a neutral (“apples and leaves in a transparent box,” ALTB) and (2) a frustrating (“attractive toy in a transparent box,” ATTB) task, both of which were followed by a narrative task. Dependent measures were emotional reactivity (positive affect, negative affect), emotion regulation (self-speech, distraction) exhibited during the ALTB and the ATTB tasks, percentage of stuttered disfluencies (SDs) and percentage of non-stuttered disfluencies (NSDs) produced during the narratives. Results. Results indicated that preschool-age CWS exhibited significantly more negative emotion and more self-speech than preschool-age CWNS. For CWS only, emotion regulation behaviors (i.e., distraction, self-speech) during the experimental tasks were predictive of stuttered disfluencies during the subsequent narrative tasks. Furthermore, for CWS there was no relation between emotional processes and non-stuttered disfluencies, but CWNS's negative affect was significantly related to nonstuttered disfluencies. Conclusions. In general, present findings support the notion that emotional processes are associated with childhood stuttering. Specifically, findings are consistent with the notion that preschool-age CWS are more emotionally reactive than CWNS and that their self-speech regulatory attempts may be less than effective in modulating their emotions. Educational objectives. The reader will be able to: (a) communicate the relevance of studying the role of emotion in developmental stuttering close to the onset of stuttering and (b) describe the main findings of the present study in relation to previous studies that have used different methodologies to investigate the role of emotion in developmental stuttering of young children who stutter.

The contribution of emotion to the onset, maintenance and exacerbation of developmental stuttering has long been discussed (e.g., Glauber, 1958 and Johnson and Associates, 1959; Sheehan, 1953). Alongside such discussion, numerous empirical studies of the relation of emotional processes to stuttering have been reported with most of these studies involving adults who stutter (e.g., Baumgartner and Brutten, 1983, Caruso et al., 1994, Dietrich and Roaman, 2001 and Weber and Smith, 1990). Given adults’ relatively lengthy experience with and potential learned reactions to stuttering, it is challenging to determine the nature of the association between adults’ emotion and stuttering (e.g., does experience with stuttering increase emotional response?) (e.g., Kefalianos, Onslow, Block, Menzies, & Reilly, 2012). Recently, however, more attention has been paid to the relation between emotion and stuttering in young children who stutter (e.g., Anderson et al., 2003, Arnold et al., 2011, Choi et al., in press, Conture and Walden, 2012, Eggers et al., 2010, Eggers et al., 2013, Johnson et al., 2010 and Walden et al., 2012). Increased attention to children, particularly those of preschool-age, is important because stuttering typically begins in early childhood, prior to extensive experience with stuttering and possible development of learned, perhaps well-established, reactions to the disorder. Some empirical studies of emotions and stuttering (e.g., Anderson et al., 2003 and Lewis and Goldberg, 1997) have focused on relatively stable/trait-like/dispositional (temperament) variables of emotional development. In contrast, others (e.g., Karrass et al., 2006 and Walden et al., 2012) have accessed more variable/state-like/situational (emotional reactivity, emotion regulation) components of emotional functioning. One such trait-like construct – temperament – encompasses a group of related traits (e.g., Zentner & Bates, 2008). Temperament, according to Rothbart and Bates (1998), can be described as constitutionally, biologically-based individual differences in reactivity and regulation that demonstrate consistency across various situations and relative stability over time (for general review of temperament see Rothbart, 2011 and Zentner and Shiner, 2012; for review of temperament specific to speech-language/stuttering see Conture, Kelly & Walden, 2013 ; Kefalianos et al., 2012). Thus, temperament is one attribute of the child that moderates/mediates the influence of their experiences with their environment ( Goldsmith et al., 1987). Several researchers have proposed that temperament consists of different dimensions such as adaptability to new situations or people, activity level, attention span/persistence, inhibitory control, rhythmicity, quality of mood and so forth (e.g., Rothbart et al., 2001 and Thomas and Chess, 1977). Another more state-like or situational construct – emotional reactivity – refers to the arousability of behavioral, endocrine, autonomic, and central nervous system responses to changes in the environment that have significance for one's goals and well being. Related to emotional reactivity, is the construct of emotion regulation, that has been described as consisting of ``extrinsic and intrinsic processes responsible for monitoring, evaluating, and modifying emotional reactions, especially their intensive and temporal features, to accomplish one's goals” ( Thompson, 1994; p. 27). A regulatory strategy examined in the present study and used by children as young as 3 years of age is distraction. “Distraction” or “attention deployment” (e.g., Gross, 2002) refers to the direction/engagement of attention to other aspects of the environment (e.g., object, person, event) instead of fixating on the emotionally taxing elements of the situation (e.g., Bridges & Grolnick, 1994). Attentional processes begin to play a central role in modulating arousal early on in life (e.g., Rothbart & Posner, 1985) and maintain their importance for older infants, toddlers, children and adults (e.g., Grolnick, Bridges, & Connell, 1996). Another regulatory strategy, self-speech, or private speech (i.e., overt, audible speech that is not addressed to a listener), has been extensively studied as a tool for behavioral self-regulation in the preschool years (e.g., Winsler et al., 2003 and Winsler et al., 2007) and only recently has its role in emotion regulation being empirically assessed (e.g., Day & Smith, 2013). Broderick (2001) reported that preschool-age children who were rated as well-regulated emotionally by their parents and teachers used more private speech during three different kinds of activities (i.e., free play, art activity, puzzle construction) than their peers who were characterized as poor emotion regulators. In what follows we will provide a brief review of (a) empirical studies of CWS and CWNS relative to underlying emotional processes/vulnerabilities, (b) studies that have examined the association these emotional processes have to changes in children's stuttering, and finally (c) the purpose and main research questions of the present study. 1.1. Studies of emotional processes/vulnerabilites Many of the existing studies that have examined possible differences in emotional processes between CWS and CWNS have used parent-report questionnaires (e.g., Behavioral Style Questionnaire [BSQ]; McDevitt & Carey, 1978; Dutch version of Child Behavior Questionnaire [CBQ-D]; Van den Bergh & Ackx, 2003). Results indicate that young CWS, when compared to CWNS, are rated (a) significantly higher on activity level (e.g., Anderson et al., 2003, Embrechts et al., 2000 and Eggers et al., 2010), (b) more sensitive, anxious, fearful, introverted, withdrawn (e.g., Fowlie & Cooper, 1978; cf. Embrechts et al., 2000), (c) more emotionally reactive (e.g., Karrass et al., 2006), and (d) more negative in quality of mood ( Eggers et al., 2010 and Wakaba, 1998; cf. Lewis & Goldberg, 1997). Furthermore, several studies have reported differences in attentional processes between young CWS and CWNS. CWS when compared to CWNS are reported to be (a) less adaptable to change ( Anderson et al., 2003, Howell et al., 2004 and Wakaba, 1998; cf. Lewis and Goldberg, 1997 and Williams, 2004), (b) more impulsive and less adept at attentional focusing, attentional shifting, inhibitory control, and perceptual sensitivity (e.g., Eggers et al., 2010, Embrechts et al., 2000 and Felsenfeld et al., 2010), and (c) less able to flexibly control their attention and shift attention when required to do so (e.g., Karrass et al., 2006). In general, results from these caregiver-rating studies suggest that CWS differ from CWNS in some emotion-related dimensions. Other empirical studies of between-group differences in young children's emotional processes have employed psychophysiological methodologies. Arnold et al. (2011) used electroencephalographic (EEG) indices of emotional reactivity and regulation (i.e., frontal alpha asymmetry, for further review of this method, see Coan & Allen, 2004) in preschool-age CWS and CWNS during emotionally-arousing background conversations and found no significant between-group differences in psychophysiological/EEG indices. In contrast, Jones et al. (2013) measured respiratory sinus arrhythmia (RSA), a physiological index of emotional regulation, during a baseline and two emotion-inducing video clips, as well as narrative tasks, and found that young CWS exhibited significantly lower overall RSA than their fluent peers. Furthermore, CWS, unlike their fluent peers, displayed a significant decrease of RSA change from the baseline to the narrative tasks. This latter finding was taken to suggest that during talking, CWS are less apt to engage the “social communication system” (e.g., Porges, 2007) than their normally fluent peers, perhaps because they perceive communication as a challenge. Employing another psychophysiological method, Ortega and Ambrose (2011) assessed school-age CWS’ emotional reactivity to daily stressors by measuring two stress biomarkers, salivary cortisol and alpha-amylase (for a general review of stress biomarkers, see Dickerson & Kemeny, 2004). Ortega and Ambrose reported that CWS’ levels of cortisol and alpha-amylase were significantly lower than published norms. In contrast, Van der Merwe, Robb, Lewis, and Ormond (2011) compared cortisol levels in seven preschool-age CWS and seven gender- and age-matched CWNS and found no statistically significant talker-group difference. Finally, the association of emotional processes and childhood stuttering has been studied by means of behavioral observation in a laboratory setting. Schwenk, Conture, and Walden (2007) investigated differences between preschool-age CWS and CWNS in attention focusing and reaction to irrelevant background stimuli (i.e., audible camera movement) in a laboratory setting. These authors reported that CWS, when compared to CWNS, were significantly more reactive to these environmental stimuli and less likely to quickly habituate to them. Subsequently, Johnson et al. (2010) used the disappointing gift procedure (e.g., Cole, Zahn-Waxler, & Smith, 1994) with preschool-age CWS and CWNS. This procedure involved participants receiving a desirable gift prior to a free-play conversation and a disappointing gift before a similar conversation. Nonverbal expressive behaviors (positive, negative) during receipt of each gift, as well as speech disfluencies following each gift, were coded. Johnson et al. reported that while receiving the undesirable gift, CWS exhibited more negative emotional expressions than CWNS but during the receipt of the desirable gift there was no significant talker group difference in display of positive emotion. Finally, Choi et al. (in press) studied the role of behavioral inhibition in childhood stuttering and found that, based on behavioral observation in a laboratory setting, preschool-age CWS were more likely to be behaviorally inhibited than their fluent peers, and that more behaviorally inhibited CWS exhibited more stuttered disfluencies than less behaviorally inhibited CWS. In a recent study, Eggers, De Nil, and Van den Bergh (2012) used a computerized attention test (Fan, McCandliss, Sommer, Raz, & Posner, 2002) to assess underlying attentional networks/subsystems (i.e., orienting, alerting, executive control) in young CWS and CWNS. Results from this study appear to support the notion that CWS's orienting network, the system that is responsible for selectively allocating attention to different sources of input, is less efficient than that of CWNS. Similarly, using a Go/NoGo task, Eggers, De Nil, and Van den Bergh (2013) found that CWS are lower in inhibitory control than their fluent peers. Johnson, Conture, and Walden (2012) compared the attentional abilities (i.e., attentional shifting and focusing) of young CWS and CWNS. They employed an age-appropriate modification of the Posner Cueing Task (Posner and Cohen, 1984 and Perez-Edgar and Fox, 2005 in an emotionally neutral (traditional) and an emotionally arousing condition (affect) but found no significant talker-group differences. 1.2. Relation between emotional processes and speech disfluencies Although talker-group differences in emotion and regulatory processes appear to support the notion that emotion is associated with childhood stuttering, they do not specifically link these differences in emotion to changes in actual instances of stuttering. To the present authors’ knowledge, very few studies (Arnold et al., 2011, Johnson et al., 2010 and Walden et al., 2012) have experimentally examined the relation between emotional processes (emotional reactivity, emotional regulation) and instances of stuttered (SD) and nonstuttered disfluencies (NSD) in preschool-age children. Specifically, in two of them ( Arnold et al., 2011 and Walden et al., 2012) emotion (i.e., negative and positive nonverbal expressions) and emotion regulatory behaviors (i.e., self-stimulation, distraction) as well as SDs and NSDs were coded while preschool-age CWS and CWNS produced narratives after being exposed to three different emotion-eliciting overheard conversations (happy, angry, neutral). Findings of both studies indicated that CWS who used regulatory strategies less frequently and for shorter durations were more apt to exhibit increased disfluencies. No such relation was found for CWNS. Also, Walden et al. reported that only for CWS was co-occurrence of greater negative emotionality and more frequent regulatory behaviors associated with less stuttering. Finally, Johnson et al. (2010), using the disappointing gift procedure (e.g., Cole et al., 1994) described above, reported that CWS were more disfluent after receiving a desirable than a disappointing gift, suggesting that emotions may contribute to childhood stuttering even in situations involving positive emotion. In essence, early research in this area suggests that changes in emotional processes appear to be related to changes in preschool-age CWS’ stuttering. 1.3. The present study Given the inconclusive nature of the evidence described above and the relative paucity of published experimental studies in preschool-age children who stutter, more research is needed to clarify the role emotional processes may play in the development and maintenance of childhood stuttering. Furthermore, it is important to note that emotions are influenced by surrounding events and thus their manifestation/expression might differ across everyday and/or experimental situations (i.e., Campos, Mumme, Kermoian, & Campos, 1994). Thus, in order to gain a better understanding of the role of emotions in childhood stuttering, the body of literature should contain studies using different experimental designs and emotion-eliciting conditions. The purpose of this study was two-fold: (a) to determine whether CWS significantly differ from CWNS in the amount of exhibited emotional reactivity (positive and negative affect) and emotion regulation (self-speech and distraction) behaviors during emotionally-inducing (neutral and frustrating) experimental tasks and (b) to examine the relation between CWS’ and CWNS’ emotional behaviors during the experimental tasks and their speech (dis)fluency during subsequent narratives. The hypotheses, with respect to the aforementioned two main study objectives, are presented immediately below. (1) CWS, when compared to CWNS will exhibit more negative affect, less positive affect, and less emotional regulation in response to emotion-eliciting tasks (i.e., “apples and leaves in transparent box” [ALTB] neutral task, “attractive toy in a transparent box” [ATTB] frustrating task). (2) CWNS, when compared to CWS, will exhibit a greater increase in negative affect and emotion regulation and greater decrease in positive affect between the neutral (ATLB) and the frustrating (ATTB) task. (3) For both CWS and CWNS higher emotional reactivity and lower emotion regulation exhibited during the neutral and the frustrating tasks will be related to higher frequency of stuttered and non-stuttered disfluencies during the subsequent narrative tasks. (4) CWS, when compared to CWNS, will exhibit more stuttered and non-stuttered disfluencies during the narrative following the frustrating task (ATTB) than during the narrative following the neutral task (ALTB).

Present findings – based on using direct observation of behavioral correlates of emotional reactivity and emotion regulation – provide support for the notion that preschool-age CWS are more emotionally reactive than their CWNS peers. This finding is curious, however, in light of the fact that CWS exhibit more self-speech regulatory behaviors than CWNS. Bringing together these two findings leads one to the possibility that CWS's regulatory attempts may not be very effective in modulating their emotions. Indeed, for preschool-age CWS, there appears to be a link between emotion regulation strategies and stuttered disfluencies, with self-speech seemingly inhibiting fluency whereas attention shifting, or distraction, seemingly facilitating fluent speech-language production. These latter findings suggest that the association between emotion regulation and disruption in speech fluency could be influenced by various permutations of attentional processes, relatively unregulated emotional arousal, and/or competing communicative intentions. However, further empirical research is needed to experimentally investigate these possibilities, with results of such research hopefully further elucidating the association between preschool-age CWS's emotional processes and their speech–language planning and production. Overall, however, present findings support the notion that emotional processes are associated with childhood stuttering and may possibly contribute to the difficulties that at least some CWS have establishing normally fluent speech.