Luca Vizioli

• Professor (Assistant) at University of Minnesota

Purpose To develop and characterize a 128‐channel head array for brain imaging at 10.5 T, evaluate signal‐to‐noise ratio (SNR) relative to ultimate intrinsic SNR (uiSNR) and lower field strengths, and demonstrate human brain anatomical and functional imaging with this unique magnetic field and high‐channel‐count array. Methods The coil consists of...

In our dynamic environments, predictive processing is vital for auditory perception and its associated behaviors. Predictive coding formalizes inferential processes by implementing them as information exchange across cortical layers and areas. With laminar-specific blood oxygenation level dependent we measured responses to a cascading oddball parad...

The use of submillimeter resolution functional magnetic resonance imaging (fMRI) is increasing in popularity due to the prospect of studying human brain activation non-invasively at the scale of cortical layers and columns. This method, known as laminar fMRI, is inherently signal-to-noise ratio (SNR)-limited, especially at lower field strengths, wi...

One of the most important new frontiers in the effort to improve the spatial resolution and accuracy of imaging of human brain activity is the recent development of greater than 10 Tesla magnetic fields. Here we present initial results for 10.5 Tesla Blood Oxygenation Level Dependent (BOLD) based functional brain imaging (fMRI) of the human brain a...

Purpose To develop and characterize the performance of a 128-channel head array for brain imaging at 10.5 tesla and evaluate the potential of brain imaging at this unique, >10 tesla magnetic field. Methods The coil is composed of a 16-channel self-decoupled loop transmit/receive array with a 112-loop receive-only (Rx) insert. Interactions between...

Purpose Toward pushing the boundaries of ultrahigh fields for human brain imaging, we wish to evaluate experimentally achievable SNR relative to ultimate intrinsic SNR (uiSNR) at 10.5T, develop design strategies toward approaching the latter, quantify magnetic field–dependent SNR gains, and demonstrate the feasibility of whole‐brain, high‐resolutio...

Functional magnetic resonance imaging (fMRI) has emerged as an essential tool for exploring human brain function. Submillimeter fMRI, in particular, has emerged as a tool to study mesoscopic computations. The inherently low signal-to-noise ratio (SNR) at submillimeter resolutions warrants the use of denoising approaches tailored at reducing thermal...

A single dose of psilocybin, a psychedelic that acutely causes distortions of space–time perception and ego dissolution, produces rapid and persistent therapeutic effects in human clinical trials1–4. In animal models, psilocybin induces neuroplasticity in cortex and hippocampus5–8. It remains unclear how human brain network changes relate to subjec...

Purpose: To develop multichannel transmit and receive arrays towards capturing the ultimate intrinsic-SNR (uiSNR) at 10.5 Tesla (T) and to demonstrate the feasibility and potential of whole brain, high-resolution human brain imaging at this high field strength. Methods: A dual row 16-channel self-decoupled transmit (Tx) array was converted to a 16T...

Functional magnetic resonance imaging (fMRI) has emerged as an essential tool for exploring human brain function. Submillimeter fMRI, in particular, has emerged as a tool to study mesoscopic computations. The inherently low signal to noise ratio (SNR) at submillimeter resolutions warrants the use of denoising approaches tailored at reducing thermal...

Functional MRI (fMRI) data are severely distorted by magnetic field (B0) inhomogeneities which currently must be corrected using separately acquired field map data. However, changes in the head position of a scanning participant across fMRI frames can cause changes in the B0 field, preventing accurate correction of geometric distortions. Additional...

The characterization of individual functional brain organization with Precision Functional Mapping has provided important insights in recent years in adults. However, little is known about the ontogeny of inter-individual differences in brain functional organization during human development, but precise characterization of systems organization duri...

As the neuroimaging field moves towards detecting smaller effects at higher spatial resolutions, and faster sampling rates, there is increased attention given to the deleterious contribution of unstructured, thermal noise. Here, we critically evaluate the performance of a recently developed reconstruction method, termed NORDIC, for suppressing ther...

FMRI has become a key tool for human neuroscience. At ultra-high field (=> 7 Tesla) it is possible to acquire images with submillimeter spatial precision, which allows examinations of mesoscale functional organization. Studying the brain at this scale does not come without its challenges, however. To tackle some of these challenges, we propose an a...

Multichannel transmit (Tx) arrays are essential for ultra-high fields. In the absence of commercial options, such arrays must be built in-house. Prior to human imaging, however, safe operations limits for specific absorption rate (SAR) must be established. This is done using EM simulations, the accuracy of which has to be verified by comparing meas...

High spatial and temporal resolution across the whole brain is essential to accurately resolve neural activities in fMRI. Therefore, accelerated imaging techniques target improved coverage with high spatio-temporal resolution. Simultaneous multi-slice (SMS) imaging combined with in-plane acceleration are used in large studies that involve ultrahigh...

Functional magnetic resonance imaging (fMRI), a non-invasive and widely used human neuroimaging method, is most known for its spatial precision. However, there is a growing interest in its temporal sensitivity. This is despite the temporal blurring of neuronal events by the blood oxygen level dependent (BOLD) signal, the peak of which lags neuronal...

Functional magnetic resonance imaging (fMRI) has become an indispensable tool for investigating the human brain. However, the inherently poor signal-to-noise-ratio (SNR) of the fMRI measurement represents a major barrier to expanding its spatiotemporal scale as well as its utility and ultimate impact. Here we introduce a denoising technique that se...

As the neuroimaging field moves towards detecting smaller effects at higher spatial resolutions, and faster sampling rates, there is increased attention given to the deleterious contribution of unstructured, thermal noise. Here, we critically evaluate the performance of a recently developed reconstruction method, termed NORDIC, for suppressing ther...

Functional magnetic resonance imaging (fMRI), a non-invasive and widely used human neuroimaging method, is most known for its spatial precision. However, there is a growing interest in its temporal sensitivity. This is despite the temporal blurring of neuronal events by the blood oxygen level dependent (BOLD) signal, the peak of which lags neuronal...

High spatial and temporal resolution across the whole brain is essential to accurately resolve neural activities in fMRI. Therefore, accelerated imaging techniques target improved coverage with high spatio-temporal resolution. Simultaneous multi-slice (SMS) imaging combined with in-plane acceleration are used in large studies that involve ultrahigh...

Functional MRI (fMRI) is commonly used for interpreting neural activities across the brain. Numerous accelerated fMRI techniques aim to provide improved spatiotemporal resolutions. Among these, simultaneous multi-slice (SMS) imaging has emerged as a powerful strategy, becoming a part of large-scale studies, such as the Human Connectome Project. How...

Magnetic resonance imaging (MRI) is a technique that scans the anatomical structure of the brain, whereas functional magnetic resonance imaging (fMRI) use the same basic principles of atomic physics as MRI scans but image metabolic function. A major goal of MRI and fMRI study is to precisely delineate various types of tissues, anatomical structure,...

The brain is organized into distinct, flexible networks. Within these networks, cognitive variables such as attention can modulate sensory representations in accordance with moment-to-moment behavioral requirements. These modulations can be studied by varying task demands; however, the tasks employed are often incongruent with the postulated functi...

Over the past nearly 30 years, functional MRI (fMRI) has transformed the way in which we study the brain non-invasively, allowing neuroscientists to tackle questions that previously could only be addressed by means of invasive electrophysiology, and which had thus remained elusive. In this chapter, we will provide an overview of some of the main ap...

Functional magnetic resonance imaging (fMRI) has become one of the most powerful tools for investigating the human brain. However, virtually all fMRI studies have relatively poor signal-to-noise ratio (SNR). We introduce a novel fMRI denoising technique, which removes noise that is indistinguishable from zero-mean Gaussian-distributed noise. Therma...

The brain is organized into distinct, but not rigid, networks. Sensory systems, for example, are enormously flexible, with cognitive variables such as attention, value, and memory able to alter sensory representations in accordance with moment-to-moment behavioral demands. Understanding these top-down modulations requires several experimental consi...

At ultra-high field, fMRI voxels can span the sub-millimeter range, allowing the recording of blood oxygenation level dependent (BOLD) responses at the level of fundamental units of neural computation, such as cortical columns and layers. This sub-millimeter resolution, however, is only nominal in nature as a number of factors limit the spatial acu...

Human ventral temporal cortex (VTC) is critical for visual recognition. It is thought that this ability is supported by large-scale patterns of activity across VTC that contain information about visual categories. However, it is unknown how category representations in VTC are organized at the submillimeter scale and across cortical depths. To fill...

At ultra-high field, fMRI voxels can span the sub-millimeter range, allowing the recording of blood oxygenation level dependent (BOLD) responses at the level of fundamental units of neural computation, such as cortical columns and layers. This sub-millimeter resolution, however, is only nominal in nature as a number of factors limit the spatial acu...

Advances in hardware, pulse sequences, and reconstruction techniques have made it possible to perform functional magnetic resonance imaging (fMRI) at sub-millimeter resolution while maintaining high spatial coverage and acceptable signal-to-noise ratio. Here, we examine whether sub-millimeter fMRI can be used as a routine method for obtaining accur...

Background: fMRI provides spatial resolution that is unmatched by non-invasive neuroimaging techniques. Its temporal dynamics however are typically neglected due to the sluggishness of the hemodynamic signal. New methods: We present temporal multivariate pattern analysis (tMVPA), a method for investigating the temporal evolution of neural repres...

Advances in hardware, pulse sequences, and reconstruction techniques have made it possible to perform functional magnetic resonance imaging (fMRI) at sub-millimeter resolution while maintaining high spatial coverage and acceptable signal-to-noise ratio. Here, we examine whether ultra-high-resolution fMRI can be exploited for routine use in neurosci...

Background fMRI provides spatial resolution that is unmatched by any non-invasive neuroimaging technique. Its temporal dynamics however are typically neglected due to the sluggishness of the hemodynamic based fMRI signal. New Methods We present temporal multivariate pattern analysis (tMVPA), a method for investigating the temporal evolution of neu...

Understanding how humans form a coherent percept of the visual word represents a major endeavor for cognitive and vision scientists alike. Variations in task demands elicit different neural representations of identical visual input. However, it remains unclear how and where in the brain external and internal inputs interact. To address this fundame...

Understanding how humans form a coherent percept of the visual word represents a major endeavor for cognitive and vision scientists alike. Variations in task demands elicit different neural representations of identical visual input. However, it remains unclear how and where in the brain external and internal inputs interact. To address this fundame...

Neuronal cortical circuitry comprises feedforward, lateral, and feedback projections, each of which terminates in distinct cortical layers [1-3]. In sensory systems, feedforward processing transmits signals from the external world into the cortex, whereas feedback pathways signal the brain's inference of the world [4-11]. However, the integration o...

David Mumford (1991) proposed a role for reciprocal topographic cortical pathways in which higher areas send abstract predictions of the world to lower cortical areas. At lower cortical areas, top-down predictions are then compared to the incoming sensory stimulation. One question that arises within this framework is the following: Do descending pr...

Introduction Activity in early visual cortex contains information about context, even in the absence of meaningful feedforward input (Smith & Muckli, 2010; Vetter, et al. 2014). To explain these contextual effects, previous work suggests that other brain areas predict sensory input, and that predictions are transmitted to early visual areas via dyn...

Sensory input and internal models combine to generate perception of the world. In vision, internal models can influence processing of feedforward sensory input in the primary visual cortex (V1) through cortical feedback. Whether such cortical feedback is retinotopically specific is still a matter of debate. Here we simultaneously recorded BOLD sign...

Ultra-high field fMRI provides the unique opportunity to record brain activation at sub-millimeter resolution. It is thus possible to reconstruct different cortical depth layers within primary and early visual cortices. Here we investigated how neural activity transfers across different cortical depth layers in V1. Specifically we ask whether thala...

Significance We addressed the open question of how the human brain recognizes personally familiar faces. A dynamic visual-stimulation paradigm revealed that familiar face recognition is achieved first and foremost in medial and anterior temporal regions of the extended face-processing system. These regions, including the amygdala, respond categoric...

Reading the non-verbal cues from faces to infer the emotional states of others is central to our daily social interactions from very early in life. Despite the relatively well-documented ontogeny of facial expression recognition in infancy, our understanding of the development of this critical social skill throughout childhood into adulthood remain...

Closing the structure-function divide is more challenging in the brain than in any other organ (Lichtman and Denk, 2011). For example, in early visual cortex, feedback projections to V1 can be quantified (e.g., Budd, 1998) but the understanding of feedback function is comparatively rudimentary (Muckli and Petro, 2013). Focusing on the function of f...

Humans have invented and transmitted distinct symbolic systems (i.e., language and numbers) over the course of evolution. As expected, these marked cultural differences have found subtle specific signatures in the brain. More recently, it has been shown that culture has also the potency to modulate the processing of non-symbolic visual information....

Cultural differences in the way individuals from Western Caucasian (WC) and East Asian (EA) societies perceive and attend to visual information have been consistently reported in recent years. WC observers favor and perceive most efficiently the salient, local visual information by directing attention to focal objects. In contrast, EA observers sho...

Globalization is a unique phenomenon in human history and a constitutive feature of modern societies. Exposure to diverse cultural groups is quickly becoming the norm and the understanding on how culture shapes human cognition a fundamental question for neuroscientists. We recently found that the face system flexibly engages into local or global ey...

Human societies are built on people accomplishing balanced individualistic and collectivistic goals to enhance their survival. Culture impacts upon human interactions and plays a critical role in regulating social goals. Western societies are individualistic, promoting values of independence, individual goals and rights. On the contrary, Eastern so...

: Irreversible facial paralysis can be surgically treated by importing both a new neural and a new motor muscle supply. Various donor nerves can be used. If a nerve supply other than the facial nerve is used, the patient has to adapt to generate a smile. If branches of the fifth cranial nerve are used, the patient has to learn to clench teeth and s...

Face recognition is not rooted in a universal eye movement information-gathering strategy. Western observers favor a local facial feature sampling strategy, whereas Eastern observers prefer sampling face information from a global, central fixation strategy. Yet, the precise qualitative (the diagnostic) and quantitative (the amount) information unde...

Cultural differences in the way individuals from Western Caucasian (WC) and East Asian (EA) societies perceive and attend to visual information have been consistently reported in recent years. WC observers favor and perceive most efficiently the salient, local visual information by directing attention to focal objects. In contrast, EA observers sho...

Eye movement strategies deployed by humans to identify conspecifics are not universal. Westerners preferentially fixate the eyes and the mouth during face recognition, whereas strikingly Easterners focus more on the face central region. However, when, where and how Preferred Viewing Locations (PVLs) for high-level visual stimuli are coded in the hu...

Human faces induce stronger involuntary orienting responses than other visual objects. We recently reported a significant increase in anti-saccade error rates for faces compared to cars and noise patterns, as well as faster pro-saccades compared to the other visual categories (Morand et al., 2010). However, when and where this preferential orientin...

Eye movement strategies deployed by humans to identify conspecifics are not universal. Westerners preferentially fixate the eyes and the mouth during face recognition, whereas strikingly Easterners focus more on the face central region. However, when, where and how Preferred Viewing Locations (PVLs) for high-level visual stimuli are coded in the hu...

Human beings are remarkably skilled at recognizing faces, with the marked exception of other-race faces: the so-called "other-race effect." As reported nearly a century ago [Feingold CA (1914) Journal of Criminal Law and Police Science 5:39-51], this face-recognition impairment is accompanied by the popular belief that other-race faces all look ali...

Cultural differences in the way adults from East Asian and Western Caucasian societies perceive and attend to visual stimuli have been consistently demonstrated in recent years. Westerners display an analytical processing style, attending to focal objects and their features. By contrast, Easterners show interest in context and relationships between...

Social experience and cultural factors shape the strategies used to extract information from faces. These external forces however do not modulate information use. Using a gaze-contingent technique that restricts information outside the fovea - the Spotlight - we recently showed that humans rely on identical face information (i.e., the eye and mouth...

Human beings share an extremely efficient biological skill in recognizing faces, with the exception of other-race (OR) faces: the so-called other-race effect (ORE). As reported by Feingold (1914) nearly a century ago, this face recognition impairment is accompanied by the popular belief that “other-race faces all look alike!” Behavioural data and c...

Human beings are natural experts at processing faces, with some notable exceptions. Same-race faces are better recognized than other-race faces: the so-called other-race effect (ORE). Inverting faces impairs recognition more than for any other inverted visual object: the so-called face inversion effect (FIE). Interestingly, the FIE is stronger for...