Implicit processes in pathological skin picking: Responses to skin irregularities predict symptom severity and treatment susceptibility

https://doi.org/10.1016/j.jbtep.2011.09.004Get rights and content

Abstract

Background and objectives

Implicit cognitive processes are relevant in understanding the development and maintenance of psychopathology and dysfunctional behaviours. The present study investigated the role of implicit processes in pathological skin picking (PSP).

Methods

Using an Approach–Avoidance Task (AAT), we examined automatic response tendencies towards skin picking-related photographs in a sample of 34 college students who suffered from PSP and participated in a randomized, waiting-list controlled treatment study.

Results

In comparison to a control sample (n = 49), PSP patients displayed significantly decelerated reaction times (distraction) in response to photographs of skin irregularities and a tendency to respond with avoidance to photographs of skin irregularities. Both distraction and avoidance in reaction to photographs of skin irregularities were significantly associated with current skin picking severity. Moreover, the strength of distraction in response to skin irregularities predicted unique variance in skin picking severity at post-measurement, over and above the effect of skin picking severity at pre-measurement and the effect of treatment condition. For the treatment condition, higher initial distraction predicted better treatment outcome (lower skin picking severity at post-measurement), whereas it predicted symptom deterioration at post-treatment for untreated participants.

Limitations

The specific characteristics of PSP patients (mainly female university students) and the relatively small sample size may compromise generalizability of findings.

Conclusions

In PSP, affective distraction in response to skin irregularities seems to characterize an important process related to symptom severity as well as treatment susceptibility.

Highlights

► We examine the role of implicit processes in pathological skin picking (PSP). ► We assess automatic responses to skin irregularities in PSP patients and controls. ► PSP patients display distraction and avoidance in response to skin irregularities. ► Distraction by skin irregularities uniquely predicts symptom severity at post-measurement. ► Responses to skin irregularities seem relevant in severity and maintenance of PSP.

Introduction

Within recent literature, a growing body of research is currently examining the role of implicit cognitive processes in various behaviours. The general assertion underlying these lines of research implicates the existence of two distinct processes which govern our behaviour and through which behavioural change can occur. Controlled processes, on one hand, are supposed to rely on knowledge about facts and values and encompass active goal construction. Traditionally, these processes are assessed using self-report measures. Implicit processes, on the other hand, are supposed to encompass fast activation and efficient resolution. Recently, these processes are assessed using indirect measures. While deliberate self-control and meta-cognition are thought to be major determinants in controlled processes, associative links and motivational orientations are assumed to constitute driving forces in implicit processes (for an overview see Strack & Deutsch, 2004).

In recent literature, indirect measures are applied with increasing frequency to a variety of domains and populations. This interest originates from the idea that indirect measures are helpful in understanding the more automatic processes involved in cognition and behaviour, which may be less readily accessible to introspection. Particular interest in these measures can be observed in the domain of pathological and dysfunctional behaviours (e.g., Heuer et al., 2007, Teachman et al., 2001, Teachman and Woody, 2003, Wiers et al., 2009), as indirect measures promise to provide more insight into the representations and mechanisms involved in psychopathology.

The present study investigated implicit processes in pathological skin picking (PSP). PSP is characterized by recurrent and excessive picking or scratching of skin, skin lesions, and minor surface irregularities up to the point of causing severe tissue damage (Odlaug & Grant, 2008). Negative consequences can be profound and include lesions, infections, pigmentations, and scarring. Research indicates that skin picking is a common behaviour which can range from benign to self-injurious (Bohne, Wilhelm, Keuthen, Baer, & Jenike, 2002). In previous research, criteria used to define PSP have been diverse (Arnold, Auchenbach, & Elroy, 2001; Odlaug & Grant, 2007; Keuthen, Jameson, Loh, Deckersbach, Wilhelm, & Dougherty, 2007 Odlaug & Grant, 2008; Snorrason, Smari, & Olafsson, 2010), but recommendations for a uniform definition of PSP, in line with related disorders such as trichotillomania (hair pulling disorder) and stereotypic movement disorder, were recently proposed (Stein et al., 2010). Clinical levels of skin picking, as defined by substantial emotional distress or functional impairment, appear to be a problem with significant prevalence, estimated to occur in approximately 1.4–5.4% of the general population (Bohne et al., 2002, Grant and Odlaug, 2009, Hayes et al., 2009, Keuthen et al., 2000, Keuthen et al., 2010).

At least two features of PSP render evaluation of implicit processes particularly interesting. First, individuals with PSP often report impulsivity or an inability to control the urge to engage in picking behaviour (Odlaug, Chamberlain, & Grant, 2010). Second, skin picking behaviour is often reported to occur automatically or unconsciously (Arnold et al., 1998, Walther et al., 2009). Therefore, the employment of indirect measures appears particularly promising in a more comprehensive understanding of the processes involved in the execution of dysfunctional skin picking behaviour.

To assess automatic response tendencies, we used an Approach–Avoidance Task (AAT; Rinck & Becker, 2007) which assesses stimulus-response associations in terms of affective behavioural reactions. Approach and avoidance tendencies are regarded as critical processes in the maintenance of dysfunctional behaviour in various disorders (Field et al., 2008, Palfai and Ostafin, 2003, Turk et al., 2001), and altered response tendencies have been repeatedly observed in social anxiety, spider phobia, and heavy drinking (Heuer et al., 2007, Lange et al., 2008, Rinck and Becker, 2007, Wiers et al., 2009). Importantly, previous research showed critical discrepancies between direct and indirect measures (Heuer et al., 2007). Indirect measures have been shown to explain unique variance in behaviour assessments over and above direct measures, thereby predicting more aspects of behaviour than could be predicted from self-report alone (Rinck & Becker, 2007).

In the present study, we investigated automatic response tendencies in response to varying types of stimuli in PSP. We distinguished between pictures of skin irregularities, pictures of healthy skin, and pictures of control stimuli. Odlaug and Grant (2008) reported that the majority of skin picking episodes is preceded by clear triggers, mostly by sight or feel of the skin. Therefore, the employment of stimuli that are visual or tactile in nature seems particularly interesting in assessing skin picking-related processes. We hypothesized that PSP patients display altered response tendencies in comparison to a control sample, and we expected this effect to be specific for skin picking-relevant stimuli (i.e., pictures of skin irregularities). Furthermore, we hypothesized that altered response tendencies are not only associated with current skin picking behaviour, but also predictive of prospective skin picking behaviour, thereby characterising a relevant process in the maintenance of symptom severity in PSP.

Section snippets

Participants and procedure

For the present study, we used data of 34 participants suffering from PSP who participated in a treatment study aimed at reducing skin picking behaviour (for more detailed information see Schuck, Keijsers, & Rinck, 2011). All participants were randomly assigned to either a four-session cognitive-behavioural treatment (n = 17) or a waiting-list condition (n = 17).

Of the 34 participants, 30 were female. Participants satisfied the following inclusion criteria: repetitive skin picking resulting in

Descriptives

With regard to skin picking severity, PSP patients (M = 9.48, SD = 3.49) differed significantly from the control sample (M = 1.76, SD = 1.76), t (81) = 12.65, p < 0.001.

For PSP patients, a repeated-measures analysis of skin picking severity from pre- to post-measurement showed a significant interaction effect between time and treatment condition, F(1,27) = 15.09, p < 0.01, ηp2 = 0.36, indicating stronger improvements in skin picking severity for the treatment condition (M = 5.43, SD = 3.41)

Discussion

The present study investigated the role of implicit processes in pathological skin picking behaviour. Results demonstrate altered response tendencies towards skin picking-related stimuli in individuals who suffer from PSP. First, PSP patients generally responded more slowly to pictures of skin irregularities compared to pictures of healthy skin and pictures of control stimuli. The control sample did not differ in reaction times across picture types. Second, PSP patients were slower to pull

Conclusions

In conclusion, individuals suffering from PSP display altered response tendencies towards skin picking-related stimuli, which are associated with current skin picking severity and predictive of prospective skin picking severity. While affective distraction in response to skin irregularities seems detrimental in untreated participants, it appears to be a favourable condition when PSP is treated. Future research needs to confirm and extend insight into the role of implicit processes in symptom

Conflict of interests

None.

Acknowledgements

This work was supported by the Behavioural Science Institute, Radboud University Nijmegen.

References (36)

  • B.L. Odlaug et al.

    Motor inhibition and cognitive flexibility in pathologic skin picking

    Progress in Neuro-Psychopharmacology and Biological Psychiatry

    (2010)
  • B.L. Odlaug et al.

    Childhood-onset pathologic skin picking: Clinical characteristics and psychiatric comorbidity

    Comprehensive Psychiatry

    (2007)
  • B.L. Odlaug et al.

    Clinical characteristics and medical complications of pathologic skin picking

    General Hospital Psychiatry

    (2008)
  • T.P. Palfai et al.

    Alcohol-related motivational tendencies in hazardous drinkers: assessing implicit response tendencies using the modified-IAT

    Behaviour Research and Therapy

    (2003)
  • M. Rinck et al.

    Approach and avoidance in fear of spiders

    Journal of Behavior Therapy and Experimental Psychiatry

    (2007)
  • K. Roelofs et al.

    Gaze direction differentially affects avoidance tendencies to happy and angry faces in socially anxious individuals

    Behaviour Research and Therapy

    (2010)
  • K. Schuck et al.

    The effects of brief cognitive-behaviour therapy for pathological skin picking: a randomized comparison to wait-list control

    Behaviour Research and Therapy

    (2011)
  • I. Snorrason et al.

    Emotion regulation in pathological skin picking: Findings from a non-treatment seeking sample

    Journal of Behavior Therapy and Experimental Psychiatry

    (2010)
  • Cited by (16)

    • Characteristics of 262 adults with skin picking disorder

      2022, Comprehensive Psychiatry
      Citation Excerpt :

      Skin picking disorder was first described by Eramus Wilson over a century ago [2]. Although skin picking disorder was recognized as a distinct psychiatric disorder classified in the Diagnostic and Statistical Manual Version 5 (DSM-5) under the category of “obsessive compulsive and related disorders”, most references to it are limited to small case series (n < 60) that used various diagnostic criteria as they were performed before the DSM nosological system had included skin picking disorder [3–8]. Larger studies have had sample sizes of up to 760, but these are generally from online surveys (i.e. did not include any gold-standard in-person clinical assessments), also before DSM-5 and where exclusionary criteria were not assessed [9,10].

    • Biased approach-avoidance tendencies in psychopathology: A systematic review of their assessment and modification

      2020, Clinical Psychology Review
      Citation Excerpt :

      Moreover, the effect on the behavioral task was mediated by the strength of the AA tendency at post-test. Only one assessment study has been conducted in skin picking disorder (Schuck, Keijsers, & Rinck, 2012). The results showed an ApB for stimuli depicting skin irregularities, which was absent in healthy controls.

    • An interrogation of cognitive findings in pediatric obsessive-compulsive and related disorders

      2015, Psychiatry Research
      Citation Excerpt :

      It has been suggested that the findings described above may be due to the plasticity of the brain during the developmental stages of life (Andres et al., 2008). Research among adults with OCD has generally shown disconcerting evidence for the persistence of cognitive deficits following successful treatment of symptoms (Nielen and den Boer, 2003; Chamberlain et al., 2005; Roh et al., 2005; Bannon et al., 2006) though some exceptions within the OCD (Moritz et al., 2001; Kuelz et al., 2006) as well as the PSP (Schuck et al., 2012) literature do exist. These stable deficits seen more often in adults may represent a missed opportunity for early intervention and supports the need for more research and better informed intervention closer to the age of onset for pediatric OCRDs, particularly with respect to cognitive deficits that may ultimately become treatment resistant.

    • Predictive validity of explicit and implicit threat overestimation in contamination fear

      2013, Journal of Obsessive-Compulsive and Related Disorders
      Citation Excerpt :

      Recently, in a non-clinical sample, an implicit measure of disgust sensitivity was found to predict avoidance on BATs measuring disgust across a variety of domains, independently of self-reported anxiety and disgust propensity (Nicholson & Barnes-Holmes, 2012). Similarly, in a sample of individuals with pathological skin picking, an implicit measure of distraction tendencies in response to pictures of skin irregularities predicted unique variance in post-treatment severity of skin picking, beyond that accounted for by a self-report measure of skin picking severity given prior to treatment (Schuck, Keijsers, & Rinck, 2012). Akin to threat overestimation, be it explicitly or implicitly measured, contamination fear can also be examined as a multifaceted construct.

    View all citing articles on Scopus
    View full text