This article has been submitted to PloS One:
Herman, A. M., & Duka, T. Keep calm and manage impulsivity: Mood as a modulator of impulsive behaviour. Plos One (submitted).
Contribution
I contributed to the study design and the interpretation of the results. I collected and analysed the data as well as prepared the initial manuscript.
Abstract
This study investigated how different mood states affect distinct subtypes of impulsivity:
motor impulsivity [measured with the Stop Signal (SST) and the 5-Choice Serial Reaction Time Task (5-CSRTT)], reflection impulsivity [assessed with the Information Sampling Task (IST)], and temporal impulsivity (the Delay Discounting Questionnaire). Eighty healthy volunteers completed two experimental sessions. During session 1, which served as a baseline measure, participants underwent a neutral mood induction procedure. In Session 2, they were randomly allocated to one of the mood-induction groups (Neutral, Positive, Sad, and Anxiety). Mood state ratings included bipolar visual analogue scales on mood (positive/negative), tension/relaxation and arousal (tired/active). No group effect was found on any of the impulsivity measures.
Correlational analyses between mood changes (following the mood manipulation procedures) and behaviour in the tasks revealed that increased relaxation was related to increased
information sampling in the IST (decreased reflection impulsivity). In addition, the more active subjects reported to be, the more likely they were to choose a delayed reward over the
immediate one (decreased temporal impulsivity). These results indicate that subjective changes in mood state are associated with behavioural impulsivity levels. Importantly, distinct facets of impulsivity (reflection, motor and temporal) are differently affected by changes in mood state.
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Keywords: Stop Signal Task, Delay Discounting, Information Sampling Task, 5-Choice Serial Reaction Time Task, Emotions
Introduction
Impulsivity is often described as a tendency to act rapidly without taking into account consequences of one’s actions (Dalley et al., 2011). It is generally considered to be maladaptive as impulsivity is associated with risky sexual activities (Winters, Botzet, Fahnhorst, Baumel, &
Lee, 2009), gambling (Hodgins & Holub, 2015; Lai, Ip, & Lee, 2011; Lawrence, Luty, Bogdan, Sahakian, & Clark, 2009), smoking (Mitchell, 1999) and binge drinking (Bø, Billieux, &
Landrø, 2016; Sanchez-Roige et al., 2014). Furthermore, deficits in impulse control, both behavioural and trait characteristic, are related to several disorders such as attention deficit and hyperactivity disorder (ADHD), manic episodes of bipolar disorder, borderline personality disorder, Parkinson’s disease, schizophrenia, eating disorders or substance abuse (American Psychiatric Association, 2013).
Given the importance of impulsivity both in everyday life and in clinical practice, it is vital to understand the modulators of impulsive behaviour. Numerous studies show that negative emotions exert a great impact not only on our actions but also on decision-making processes.
Tice and colleagues (Tice et al., 2001) demonstrated that experiencing negative emotions leads to limited self-control, which in turn results in impulsive behaviours such as compulsive eating, reduced delayed gratification or procrastination. Experience of stress or anxiety has also been shown to lead to maladaptive behaviours including smoking, comfort-eating or drinking alcohol (Abrantes et al., 2008; Bekker et al., 2004; Cooper et al., 1995; Swendsen et al., 2000). Such activities are believed to serve as a coping mechanism. Episodes of binge eating and vomiting in patients with bulimia nervosa are related to prior states of increased self-reported negative mood, stress or feelings of anger (Engel et al., 2007; Smyth et al., 2007) and engagement in purging behaviours leads to decrease in negative emotions (Smyth et al., 2007).
On the other hand, the beneficial impact of positive affect in everyday life has been reported in several studies. For instance, people in a good mood state perform better at creative problem-solving tasks (Subramaniam, Kounios, Parrish, & Jung-Beeman, 2009) and show increased cognitive flexibility (Nadler, Rabi, & Minda, 2010). However, high levels of positive affect may also be associated with undertaking risky and impulsive behaviours such as heavy-drinking as part of celebrations (Del Boca, Darkes, Greenbaum, & Goldman, 2004; Peacock, Cash, Bruno, & Ferguson, 2015) or gambling (Cyders & Smith, 2008a).
The evidence summarised above provides support for the link between emotional states and impulsivity, as well as an interaction between the two in forming our actions and
motivations contributing to addictive behaviours. However, little is known about how exactly emotional states impact the different facets of behavioural impulsivity. Therefore, the current experiment aimed to examine how incidental changes in mood state influence the distinct impulsivity subtypes using common laboratory tests.
Due to the multifaceted nature of impulsivity (Caswell et al., 2015; Evenden, 1999b;
Sharma, Markon, & Clark, 2014; Whiteside & Lynam, 2001), several independent measures were used to capture a wider range of impulsivity dimensions: impulsive tendencies (personality traits), reflection, temporal, motor ‘stopping’ and ‘waiting’ impulsivity, and inattention. We hypothesised that negative emotional state might reduce inhibitory control, as worry and
rumination are costly in terms of cognitive resources (Hirsch & Mathews, 2012). Since negative affect has been related to an increase in task-unrelated thoughts (Smallwood et al., 2009), we also hypothesised that sadness and anxiety might be related to increased impulsivity on the tasks which require attention. On the other hand, positive affect might decrease reflection impulsivity by improving efficiency (Isen & Means, 1983; Isen et al., 1991). Positive affect could also improve self-regulation (Tice, Baumeister, Shmueli, & Muraven, 2007) and, therefore, make individuals more likely to wait for their incentive (decrease temporal impulsivity).
Methods
Participants
Eighty-three volunteers (50 females) were recruited from the University of Sussex community, providing consent to participate in the study. Sample size was motivated by previous studies using similar methodologies (Smallwood et al., 2009; Tice et al., 2007, 2001;
Yuen & Lee, 2003). Participants were informed that the study investigated the effects of experience on cognitive tasks performance. The inclusion criteria were following: age 18-35 years old, fluency in English, no current diagnosis of any mental or neurological disorders, and no current pharmacological treatment (except birth control). During the experiment participants’
olfactory abilities were tested; therefore, additional exclusion criteria was anosmia, hay fever or cold. Data from this part of the procedure will be reported elsewhere. Participants were
instructed not to consume any caffeine-containing products or any other substances which may affect their activity level on the days of testing. The study was approved by the local Ethics Committee. All participants were compensated for their time.
Materials
Nuffield Hospitals Medical History Questionnaire assessed demographic details, past and present health status (to confirm meeting study inclusion criteria), use of medications and recreational drugs, and an estimate of a number of cigarettes smoked per day.