Rapid Formation of Pragmatic Rule Representations in the Human Brain during Instruction-Based Learning

Abstract

The present functional magnetic resonance imaging study investigated the instruction-based learning of novel arbitrary stimulus-response mappings in order to understand the brain mechanisms that enable successful behavioral rule implementation in the absence of trial-and-error learning. We developed a novel task design that allowed the examination of rapidly evolving brain activation dynamics starting from an explicit instruction phase and further across a short behavioral practice phase. As a first key result, the study revealed that different sets of brain regions displayed either decreasing or increasing activation profiles already across the first few practice trials, suggesting an impressively rapid redistribution of labor throughout the brain. Furthermore, behavioral performance improvement across practice was tightly coupled with brain activation during the practice phase (caudate nucleus), the instruction phase (lateral midprefrontal cortex), or both (lateral premotor cortex bordering prefrontal cortex). Together, the present results provide first important insights into the brain systems involved in the rapid transfer of control from initially abstract rule representations induced by explicit instructions toward pragmatic representations enabling the fluent behavioral implementation.

Disrupting Prefrontal Cortex Prevents Performance Gains from Sensory-Motor Training

“…Previous research has used brain imaging methods to examine the neural substrates of response selection and training (Jiang and Kanwisher, 2003;Dux et al, 2006Dux et al, , 2009Marois et al, 2006;Sigman and Dehaene, 2008;Ivanoff et al, 2009;Hesselmann et al, 2011), including the initial learning of new arbitrary stimulus-response mappings (Brovelli et al, 2008;Ruge and Wolfensteller, 2010). Our findings provide strong evidence that the left pLPFC plays a causal role in both response selection and response selection training.…”

Automatic motor activation by mere instruction

“…Neuroimaging studies suggest that a frontal parietal network involved in task-rule implementation might be instrumental for the occurrence of IB-TRCEs (e.g. Hartstra, Kühn, Verguts, & Brass, 2011;Hartstra, Waszak, & Brass, 2012;Ruge & Wolfensteller, 2010). In this network, the inferior frontal sulcus appears to be implicated in the formation of S-R links, while a sizeable part of the network is responsible for the coding of responses in areas related to motor control such as the anterior IPS, premotor cortices and the pre-SMA (Hartstra et al 2012).…”

Distinct contributions of the caudate nucleus, rostral prefrontal cortex, and parietal cortex to the execution of instructed tasks

“…With practice, instructions are transformed into more specialized representations of the various terms and actions to be performed. This representation is what we have previously called a "mental template," and what Ruge and Wolfensteller (2010) have named "pragmatic representations." Cole et al (2010) argued that, when such a template has already been established for a task, it can be accessed directly when encoding instructions.…”

“…For this reason, traditional paradigms are not well suited to study the process by which instructions are interpreted. To overcome this difficulty, researchers have devised paradigms in which many different instructions (corresponding to different "tasks") are given during the course of experiments (Brass, Wenke, Spengler, & Waszak, 2009;Cole, Bagic, Kass, & Schneider, 2010;Hartstra, Kühn, Verguts, & Brass, 2011;Ruge & Wolfensteller, 2010;Stocco, Lebiere, O'Reilly et al, 2010). In these paradigms, a new "task" is introduced by presenting its specific instructions on the screen, followed by a series of one or more stimuli on which the new task is applied.…”

“…For this reason, the brain regions involved in interpreting instructions can be observed by comparing the activity of the brain when novel instructions are applied to the experimental stimuli for the first time against the brain activity occurring during subsequent applications of the same instructions. Several authors have found that regions in the LPFC were more active during the execution of novel versus practiced instructions (Brass et al, 2009;Cole et al, 2010;Hartstra et al, 2011;Ruge & Wolfensteller, 2010). Both Ruge and Wolfensteller (2010) and Cole et al (2010) reported that those regions in the LPFC that were active during the first execution of novel instructions were also located more anterior than those regions that were active for the execution of subsequent trials.…”