PT  - JOURNAL ARTICLE
AU  - Silvia Formica
AU  - Carlos González-García
AU  - Mehdi Senoussi
AU  - Marcel Brass
TI  - NEURAL OSCILLATIONS DISSOCIATE BETWEEN MAINTENANCE AND PROCEDURALIZATION OF NOVEL INSTRUCTIONS
AID  - 10.1101/2020.01.20.912162
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.01.20.912162
4099  - http://biorxiv.org/content/early/2020/01/20/2020.01.20.912162.short
4100  - http://biorxiv.org/content/early/2020/01/20/2020.01.20.912162.full
AB  - Humans are extremely efficient in rapidly and flexibly converting complex symbolic instructions into novel behaviors. Previous evidence and theoretical models suggest that the implementation of a novel instruction requires the reformatting of its declarative content into an action-oriented code optimized for the execution of the instructed behavior. While neuroimaging research focused on identifying the brain areas involved in such process, its temporal profile and electrophysiological characteristics remain unknown. In the present study, we recorded EEG while we asked participants to either simply maintain declaratively the content of novel S-R mappings for recognition or to proactively prepare for their implementation. By means of time-frequency analyses, we isolated the oscillatory features specifically associated with the proceduralization of the encoded instruction. Before the onset of the implementation target, we observed stronger delta/low-theta activity over frontal electrodes and a significant suppression in mu and beta activity over central electrodes. On the contrary, activity in the alpha band showed no differences between the two tasks. Together, these results support the crucial role attributed to prefrontal regions in orchestrating complex task setting and further extend on it by characterizing the temporal and frequency profile of this process. Moreover, we highlight the critical involvement of motor activity in the proactive preparation for novel instruction implementation.Significance Statement Humans developed the unique ability of converting novel instructions in effective behavior. This skill is associated with activity in frontoparietal brain regions, whose interplay supports the reformatting of the declarative content of the instruction into an action-guiding representation. However, the time-resolved unfolding of such cognitive processes is still poorly understood. Here, we investigated how oscillatory brain activity differed between simple maintenance and reformatting of novel instructions. In preparation to the target, we observed differences in lower frequencies over frontal regions, and oscillatory features of motor preparation. Together, these results suggest that instruction implementation is mediated by the exertion of top-down cognitive control, reflected in theta dynamics, and motor-related activation.