Functional Magnetic Resonance Imaging (fMRI) has opened the possibility to investigate how brain activity is modulated by behavior. Most studies so far are bound to one single task, in which functional responses to a handful of contrasts are analyzed and reported as a group average brain map. Contrariwise, recent data-collection efforts have started to target a systematic spatial representation of multiple mental functions.
In this paper, researchers leveraged the Individual Brain Charting (IBC)* dataset, a high-resolution task-fMRI dataset acquired in a fixed environment, in order to study the feasibility of individual mapping. They first verified that the IBC brain maps reproduce those obtained from previous, largescale datasets using the same tasks. They secondly confirmed that the elementary spatial components, inferred across all tasks, are consistently mapped within and, to a lesser extent, across participants. In a third time, they demonstrated the relevance of the topographic information of the individual contrast maps, showing that contrasts from one task can be predicted by contrasts from other tasks. At last, they showcased the benefit of contrast accumulation for the fine functional characterization of brain regions within a pre-specified network. To this end, they analyzed the cognitive profile of functional territories pertaining to the language network and proved that these profiles generalize across participants.
Representation of the cerebral regions activated during the execution of different tasks.
B. Thirion © CEA/INRIA
These results show that the use of rich task data sets is necessary in studies of cognitive mapping and individual modeling of the human brain.
*IBC : Funded by the Human Brain Project, Individual Brain Charting is a collaborative project involving NeuroSpin that aims to acquire a set of high-resolution functional MRI maps of the human brain during the performance of behavioral tasks. The data, freely available, are used to build a macroscopic functional atlas including cognitive mapping. The objective of the IBC project is to establish a high-resolution (1.5 mm) multi-task fMRI data corpus that will be used to develop a comprehensive neurocognitive functional atlas of the human brain.