Personality and Impulsivity

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Finally, like most lab-based situations, behavioural measures of impulsivity are limited in their external validity so that behaviour disinhibition may be different in the lab setting compared to external settings. Additionally the lab tasks rely on multiple concurrent processes such as concentration, memory and attention as well as the targeted construct.

The cued go/no-go task focuses on the ability to inhibit instigated prepotent responses as an indicator of impulsivity. The task involves a preliminary go/no-go cue being shown before the go/no-go target is shown. There is a higher proportion of valid cues that tend to facilitate response inhibition and speed in execution compared to invalid cues which tend to impair response inhibition and slow speed of execution. A failure to inhibit a ‘no-go; response following a ‘go’ cue is indicative of impulsive behaviour and low inhibitory control (Marsh, Doughtery, Marthias, Moeller, & Hicks, 2002). To measure the validity of the go/no-go task in correctly identifying impulsivity, control groups were compared to clinical ADHD groups, a condition associated with higher levels of impulsive behaviour. Research has shown that clinical populations of children and teenagers diagnosed with ADHD more errors and slower inhibition response than control groups (Weafer, Milich & Fillmore, 2011). Consequently the go/no-go task shows construct validity in measuring impulsivity yet lacks significant external validity (Marsh et al., 2002). This task focuses on the ability to resist proactive interference and does not indicate a long-term trait of impulsivity.

An alternate lab-based impulsivity test is the two choice impulsivity paradigm (TCIP). This task uses a discrete choice procedure so that participants can choose a shorter delay, associated with a smaller reward or conversely a longer delay, associated with a longer reward. The task works by manipulating the delay-reward contingencies that may be fixed or variable. The TCIP has been validated across a range of adolescents to adults with consistent evidence showing that those characterised by high levels of impulsive behaviour show preference for the shorter-smaller combination of delay and reward (Morgan, Gray & Snowden, 2011). Yet, little has been done to examine the retest validity or reliability of the TCIP. Similarly to the go/no-go task, the TCIP measures inability of delay response as a construct of impulsivity but is not reflective of longer-term traits and is a better indicator of a state level of impulsivity.

Following these examples it is important to review these existing measures of impulsivity and determine whether or not self-report and lab-based tasks assess similar or distinct underlying constructs. In order to avoid issues with the definition of impulsivity and content validity, this comparison will use the five dimension model of impulsivity as outlined in the UPPS-P and the five dimension model for lab-based tasks put forward by Cyders and Coskunpinar (2011). According to Cyders and Coskunpinar (2011), using these models there is a very small level of overlap between these two testing methods but primarily they measure distinctly different constructs of impulsivity. Previous research has clearly identified that self-report measures tend to be limited in measuring states of impulsivity and predicting behaviour. On the other hand, lab-based tests are far more relevant in state level of impulsivity and are not accurate in identifying long-term traits.

However, both forms of testing have clearly identified impulsivity as a multidimensional construct, consisting of a number of distinct processes and behaviours (Perales, Verdejo-Garcia, Moya, Lozano, & Perez-Garcia, 2009). The progress of identifying and measuring unidimensional traits within the construct of impulsivity lends itself to greater validity and more accurate predictions of behaviour. The implications from this review show that in order to fully examine complex targeted traits of personality such as impulsivity, both lab-based and self-report tests are necessary to build a comprehensive view of both trait and state characteristics. Furthermore, this study suggests that the characteristics being measured by lab-based or self-report tasks should not be identified by the same overarching construct but rather as separate unidimensional aspects of impulsivity.

Due to the multidimensional aspect of impulsivity, there are a number of valid and reliable forms of measurement that can take the form in either self-report or lab-based testing. Self-report tasks have been consistently shown to measure stable traits of impulsivity and are useful for people with insight into their own feelings, thoughts and behaviour. These are particularly applicable to large groups of participants who can be measured and scored quickly and inexpensively. Conversely, lab-based tasks that measure state level impulsivity have been shown to be more robust against fake or manipulative responses and can prove a better predictor of behaviour in specific scenarios. Further research may be conducted into the long-term reliability and retest validity of many of these tests as well as greater insight into the role of race, culture and gender as variables in these tests. In summary, the combination of both self-report and lab-based testing provides the most comprehensive view of an individual’s level of impulsivity by examining both the traits and states that affect impulsive behaviour.

References

Cyders, M., Coskunpinar, A. (2011). Measurement of constructs using self-report and behavioural lab tasks: Is there overlap in nomothetic span and construct representation for impulsivity? Clinical Psychology Review, 31, 965-982.

Cyders, M., & Coskunpinar, A. (2012). The relationship between self-report and lab task conceptualizations of impulsivity. Journal of Research in Personality, 46, 121-124.

Perales, J.C., Verdejo-Garcia, A., Moya, M., Lozano, O., & Perez-Garcia, M. (2009). Bright and dark sides of impulsivity: Performance of women with high and low trait impulsivity on neuropsychological tasks. Journal of Clinical and Experimental Neuropsychology, 31, 927-944.

Verdejo-Garcia, A., Lozano, O., Moya, M., Alcazar, M.A., & Perez-Garcia, M. (2010). Psychometric properties of a Spanish version of the UPPS-P Impulsive Behaviour Scale: Reliability, Validity and Association with Trait and Cognitive Impulsivity. Journal of Personality Assessment, 92, 70-77.

Meda, S.A., Stevens, M.C., Potenza, M.N., Pittman, B., Gueorguieva, R., Andrews, M.M., Thomas, A.D., Muska, C., Hylton, J.L., & Pearlson, G.D. (2009). Investigating