The neural mechanisms underlying internally and externally guided task selection

Abstract

While some prior work suggests that medial prefrontal cortex (MFC) regions mediate freely chosen actions, other work suggests that the lateral frontal pole (LFP) is responsible for control of abstract, internal goals. The present study uses fMRI to determine whether the voluntary selection of a task in pursuit of an overall goal relies on MFC regions or the LFP. To do so, we used a modified voluntary task switching (VTS) paradigm, in which participants choose an individual task to perform on each trial (i.e., a subgoal), under instructions to perform the tasks equally often and in a random order (i.e. the overall goal). In conjunction, we examined patterns of activation in the face of irrelevant, but task-related external stimuli that might nonetheless influence task selection. While there was some evidence that the MFC was involved in voluntary task selection, we found that the LFP and anterior insula (AI) were crucial to task selection in the pursuit of an overall goal. In addition, activation of the LFP and AI increased in the face of environmental stimuli that might serve as an interfering or conflicting external bias on voluntary task choice. These findings suggest that the LFP supports task selection according to abstract, internal goals, and leaves open the possibility that MFC may guide action selection in situations lacking in such top-down biases. As such, the current study represents a critical step towards understanding the neural underpinnings of how tasks are selected voluntarily to enable an overarching goal.

Influences of unconscious priming on voluntary actions: Role of the rostral cingulate zone

“…Our findings are in line with previous studies focusing on RCZ (De Pisapia et al, 2011) and AI (De Pisapia et al, 2011;Demanet et al, 2013;Orr & Banich, 2014) in resisting external influences.…”

“…Participants were also significantly more likely to choose to follow the prime's suggestion (in a prime-compatible way), than go against the prime. Brain activity in the RCZ and the AI was reported to be reduced when a free choice is biased by supraliminal external information Orr & Banich, 2014). This research shows that some parts of the 'choice network' may be influenced by information that primes free choices.…”

“…This means that, rather than introducing conflict, the external information could be facilitating decision making via these previously formed associations. Orr and Banich (2014), in contrast to Demanet et al (2013), also found conflict activation patterns for incompatible trials. Although they also used a voluntary task switching paradigm, they used flanker-style stimuli to introduce external biasing information.…”

“…Intuitively one would think that free choices are mostly determined by our own intentions and internal goals. Previous research, however, suggests that free choices may not be as free as they seem to be, and are strongly influenced by cues from the environment or past experiences (Bargh et al, 2001;Arrington & Logan, 2005;Arrington, Weaver & Pauker, 2010;Wenke, Fleming & Haggard, 2010;Orr & Weissman, 2011;Orr, Carp, & Weissman, 2012;Demanet et al, 2013;Orr & Banich, 2014). Wenke and colleagues (2010), for example, found that subliminal primes influence the responses on free choice trials in such a way that people responded significantly more slowly when they chose to act against the prime (in a prime-incompatible way).…”

“…24 previously been related to intentional choice Orr and Banich, 2014;Forstmann et al, 2006) and are thought to be part of an intentional action network (Seeley et al, 2007;De Pisapi et al, 2012). Hence we succeeded in our first goal of identifying involvement of the RCZ and other regions within the intentional choice network.…”