Poster #34 - Neurobehavioral Correlates of the Longitudinal Development of Delay Discounting: Influences of Inhibitory Control and BIS

• In Event: 2-110 - Poster Session 07
  In Poster Session: PS 07 Section - Cognitive Processes

Integrative Statement

Delay discounting is related to a host of potentially health-compromising behaviors including substance use, sexual risk-taking, and gambling (Amlung, Vedelago, Acker, Balodis, & MacKillop, 2017). Yet, research identifying how neural and behavioral correlates of inhibitory control relate to typical delay discounting development is scarce. Competing neurobehavioral decisions systems (CNDS) theory suggests the extent of imbalance between competing behavioral and control systems affects vulnerability for maladaptive decision-making behaviors (Bickel, Jarmolowicz, Mueller, & Gatchalian, 2011). The frontoparietal system is believed to support the top-down inhibition of delay discounting impulses while the limbic regions are related to bottom-up reinforcement sensitivity (Koffarnus, Jarmolowicz, Mueller, & Bickel, 2013). Studies involving functional neuroimaging inhibitory control tasks have demonstrated recruitment of the right insula during response inhibition (Bari & Robbins, 2013; Cai, Ryali, Chen, Li, & Menon, 2014; Garavan, Hester, Murphy, Fassbender, & Kelly, 2006), with implications for top-down functioning (Dosenbach, Fair, Cohen, Schlaggar, & Petersen, 2008). The Behavior Inhibition System (BIS) is related to bottom-up inhibitory control processes related to inhibition of goal-oriented behaviors (Carver & White, 1994; Gray, 1970). We examined how the BIS interacts with neural activation during an inhibitory control task to predict longitudinal change in delay discounting. A sample of 157 adolescents, (aged 13-14 at Time 1, 52% male) were measured at two time points, 4 years apart. BIS scores were computed using adolescents’ self-reported questionnaire data, with higher scores indicative of greater behavioral inhibition and behavioral performance and neural correlates of inhibitory control were assessed via the Multiple Source Interference Task (MSIT) at Time 1. Delay discounting was assessed at Times 1 and 4 using a computerized delay discounting task (Johnson & Bickel, 2002). Individual delay discounting rates were calculated using hyperbolic k values as an index for discounting behavior (Mazur, 1987). Delay discounting residual change scores were computed at Time 4 by controlling for baseline delay discounting. Lower residual change scores were indicative of declining trends in delay discounting from Time 1 to Time 4. Results from structural equation modeling analyses revealed a significant interaction between BIS and right insula activation during the MSIT (b = –.85, SE = .33, p = .009) such that BIS was related to longitudinal declines in delay discounting when right insular hemodynamic response was average (b = –.29, SE = .13, p = .028) and high (b = .59, SE = .17, p = .001), but not low (b = .01, SE = .18, p = .938). BIS effects on longitudinal changes in delay discounting did not significantly differ at any level of behavioral performance on the MSIT (b = –1.56, SE = 1.41, p = .269). These results support the hypothesized imbalance in executive and impulsive systems that explain the development of delay discounting, identifying adolescents with the combination of low BIS and hypoactivity of the right insula at risk for elevated delay discounting across adolescence.

Authors

• Kristin Peviani, Virginia Tech
  Presenting Author

• Jacob Lee, Virginia Tech Carilion Research Institute
  Non-Presenting Author

• Warren K. Bickel, Virginia Tech Carilion Research Institute
  Non-Presenting Author

• Brooks King-Casas, Department of Psychology, Virginia Tech
  Non-Presenting Author

• Jungmeen Kim-Spoon, Virginia Tech
  Non-Presenting Author