Self-Control and Impulsivity in Children: Multiple Behavioral Measures
Forzano, L. B., Michels, Jennifer L., Carapella, R. K., Conway, Patrick, Chelonis, J. J., The Psychological Record
Impulsivity, which can be conceptualized as lack of self-control (Meichenbaum & Goodman, 1971; Mischel & Ebbesen, 1970; Spira & Fischel, 2005), is featured in a number of childhood and adult disorders, including attention-deficit/hyperactivity disorder (ADHD; American Psychiatric Association, 1994; Gomez, 2003; Spira & Fischel, 2005), substance abuse (Coffey, Gudleski, Saladin, & Brady, 2003; Dom, De Wilde, Hulstijn, van den Brink, & Sabbe, 2006), borderline personality disorder (American Psychiatric Association, 1994; Chapman, Leung, & Lynch, 2008), and impulse-control disorders such as gambling (Alessi & Petry, 2003).
Given the broad use of the term impulsivity, it is not surprising that a wide range of definitions and measures have been developed for the construct of impulsivity, with researchers differentiating between two (Dickman, 1990; Swann, Bjork, Moeller, & Dougherty, 2002) or three (Dougherty, Marsh, Mathias, & Swann, 2005) subtypes of impulsivity. For example, according to Dougherty et al. (2005), impulsivity can be divided into at least three main categories, including (a) response initiation, (b) response inhibition, and (c) consequence sensitivity or reward delay.
In response initiation, impulsivity is defined as responding before full evaluation of stimuli has been completed (Dougherty et al., 2005). Typical measures are the Immediate and Delayed Memory Tasks, which are variants of the Continuous Performance Test (CPT; Rosvold, Mirsky, Sarason, Bransome, & Beck, 1956). In these tasks, stimuli are presented in rapid succession (i.e., every 1-2 s), and the individual is to respond only when a specific character appears. In this paradigm, commission errors (responding to stimuli other than the target stimulus) are considered a measure of impulsivity (Dougherty et al., 1998).
In response inhibition, the inability to inhibit a response that has already begun is defined as impulsivity (Dougherty et al., 2005). An example of measurement is the stop-signal paradigm in which individuals are instructed to respond on one key if they see an "X" and on another key if they see an "O" (Logan, Schachar, & Tannock, 1997). However, when there is an auditory tone, the individual is to inhibit the response. During the session, as the tone is introduced and removed, the reaction times (latencies) to stop responding and to begin responding again are recorded. In this paradigm, those who have longer "stop" reaction times than "go" reaction times are said to be impulsive (Logan et al., 1997).
Soreni, Crosbie, Ickowicz, and Schachar (2009) found no significant correlations between performances on the stop-signal task and commission errors in the Conners' (2004) CPT task in children with ADHD. This work supports the notion that impulsivity is multifaceted and supports the inclusion of each of these tests in their respective categories--response inhibition and response initiation. However, Avila, Cuenca, Felix, Parcet, and Miranda (2004) found a significant correlation (r=.39, p < .01) between performance on the stop-signal task and commission errors in the CPT task (AX version) in a larger sample of boys with and without ADHD. Finally, Floyd and Kirby (2001) found a significant correlation in performance on the "snack delay" task (which fits within the response-initiation category) and the "pinball" task (which fits within the response-inhibition category). These studies demonstrate that the boundary between the response-initiation and response-inhibition categories may require further definition.
In a third impulsivity category, the consequence-sensitivity/reward-delay category, self-control can be defined as the choice of a larger, more delayed reinforcer over a smaller, less delayed reinforcer, whereas impulsivity is the choice of the smaller, more immediate reinforcer over the delayed but larger reinforcer (Rachlin & Green, 1972). …