The impact of ultra-high field MRI on cognitive and computational neuroimaging

Abstract

The ability to measure functional brain responses non-invasively with ultra high field MRI (7 T and above) represents a unique opportunity in advancing our understanding of the human brain. Compared to lower fields (3 T and below), ultra high field MRI has an increased sensitivity, which can be used to acquire functional images with greater spatial resolution, and greater specificity of the blood oxygen level dependent (BOLD) signal to the underlying neuronal responses. Together, increased resolution and specificity enable investigating brain functions at a submillimeter scale, which so far could only be done with invasive techniques. At this mesoscopic spatial scale, perception, cognition and behavior can be probed at the level of fundamental units of neural computations, such as cortical columns, cortical layers, and subcortical nuclei. This represents a unique and distinctive advantage that differentiates ultra high from lower field imaging and that can foster a tighter link between fMRI and computational modeling of neural networks. So far, functional brain mapping at submillimeter scale has focused on the processing of sensory information and on well-known systems for which extensive information is available from invasive recordings in animals. It remains an open challenge to extend this methodology to uniquely human functions and, more generally, to systems for which animal models may be problematic. To succeed, the possibility to acquire high-resolution functional data with large spatial coverage, the availability of computational models of neural processing as well as accurate biophysical modeling of neurovascular coupling at mesoscopic scale all appear necessary.

Intensity‐curvature functional‐based filtering in image space and k‐space: Applications in magnetic resonance imaging of the human brain

“…Consistently, the fourth column from left reports the difference between the mode value of the edge image of the MRI and the mode value of the edge image of the five imaging modalities. The results that were closest to those obtained running the edge finder on the MRI were attained with the following two imaging techniques: De Martino et al, 2018) and the other one is the large body of methodologies that through applied computational neuroimaging had contributed to vessels segmentation (Moccia, De Momi, El Hadji, & Mattos, 2018) and also to perivascular segmentation (Ballerini et al, 2018). The methodologies are currently being developed to the purpose of addressing major human brain diseases and affections in the pathological state.…”

“…Human brain vessel imaging with MRI has been influenced in the past decade by the advent of two main novelties. One is the strength of the magnet used for MRI recording (De Cocker et al., ; De Martino et al., ) and the other one is the large body of methodologies that through applied computational neuroimaging had contributed to vessels segmentation (Moccia, De Momi, El Hadji, & Mattos, ) and also to perivascular segmentation (Ballerini et al., ). The methodologies are currently being developed to the purpose of addressing major human brain diseases and affections in the pathological state.…”

“…The quantification of iron content in the human brain is important to the understanding of diseases like Parkinson and multiple sclerosis (Ghassaban, Liu, Jiang, & Haacke, 2018). Ultrahigh-field (UHF) MRI at 7 T nowadays impacts functional MRI, which benefits of increased resolution and also opens the door to the investigation of brain functions at a submillimeter scale (De Martino et al, 2018). UHF (above 1.5 T) MRI is demonstrated to be beneficial to fluidattenuated inversion recovery (FLAIR) MRI, MR angiography for the study of stroke and cerebrovascular diseases (De Cocker et al, 2018), and also to MRI studies of the correlation between white matter integrity and the progression of cognitive decline (Riphagen et al, 2018).…”

Addressing challenges of high spatial resolution UHF fMRI for group analysis of higher‐order cognitive tasks: An inter‐sensory task directing attention between visual and somatosensory domains

“…The challenges of full FOV acquisitions at UHF have resulted in there being a limited number of studies of whole brain function at high spatial resolution to date (e.g., Boyacioglu et al, ; Goodman et al, ; Mestres‐Misse, Trampel, Turner, & Kotz, ; Vu et al, ). In particular there are few studies of cognitive function, as highlighted in a recent review article (De Martino et al, ). Although full FOV functional acquisitions are now included in the Human Connectome Project 7 T protocol (http://protocols.humanconnectome.org/) for resting state assessment.…”

The impact of correction on MP2RAGE cortical T1 and apparent cortical thickness at 7T

“…Although the majority of, in particular clinical, neuroimaging data is acquired at 1.5T or 3T magnetic field strengths, technical developments and increased availability have led to increased usage of ultra-high-field scanners (UHF, !7T) for neuroanatomical and functional studies (as recently reviewed by De Martino et al, 2017;Marques & Norris, 2017;and Ugurbil, 2017, and references herein). Compared to conventional field strengths, imaging at higher fields enables acquisition of higher signal-to-noise ratio (SNR; Pohmann, Speck, & Scheffler, 2016) data and increases in various contrasts with no or little acquisition duration penalty.…”