What makes the human brain special - from cellular function to clinical translation.

What makes the human brain special? Human neurons, glia cells, and cortical circuits have been shown to be significantly different from those of other species, including mammals. This has led to a massive effort by the neuroscience community to directly study these differences in a multimodal approach. The studies conducted include single-cell and network recordings of human tissue samples, single-cell transcriptomics, and morphological analysis of the distinct cells to better understand the underlying differences from the cellular to the systems level.

Evolutionarily conserved fMRI network dynamics in the mouse, macaque, and human brain.

Evolutionarily relevant networks have been previously described in several mammalian species using time-averaged analyses of fMRI time-series. However, fMRI network activity is highly dynamic and continually evolves over timescales of seconds. Whether the dynamic organization of resting-state fMRI network activity is conserved across mammalian species remains unclear.

A somato-cognitive action network alternates with effector regions in motor cortex.

Motor cortex (M1) has been thought to form a continuous somatotopic homunculus extending down the precentral gyrus from foot to face representations, despite evidence for concentric functional zones and maps of complex actions. Here, using precision functional magnetic resonance imaging (fMRI) methods, we find that the classic homunculus is interrupted by regions with distinct connectivity, structure and function, alternating with effector-specific (foot, hand and mouth) areas. These inter-effector regions exhibit decreased cortical thickness and strong functional connectivity to each other, as well as to the cingulo-opercular network (CON), critical for action and physiological control, arousal, errors and pain.

Carotenoids improve the development of cerebral cortical networks in formula-fed infant macaques.

Nutrition during the first years of life has a significant impact on brain development. This study characterized differences in brain maturation from birth to 6 months of life in infant macaques fed formulas differing in content of lutein, β-carotene, and other carotenoids using Magnetic Resonance Imaging to measure functional connectivity. We observed differences in functional connectivity based on the interaction of diet, age and brain networks.

Individual Variability in Functional Organization of the Human and Monkey Auditory Cortex.

Accumulating evidence shows that auditory cortex (AC) of humans, and other primates, is involved in more complex cognitive processes than feature segregation only, which are shaped by experience-dependent plasticity and thus likely show substantial individual variability. However, thus far, individual variability of ACs has been considered a methodological impediment rather than a phenomenon of theoretical importance. Here, we examined the variability of ACs using intrinsic functional connectivity patterns in humans and macaques.

Maternal Interleukin-6 Is Associated With Macaque Offspring Amygdala Development and Behavior.

Human and animal cross-sectional studies have shown that maternal levels of the inflammatory cytokine interleukin-6 (IL-6) may compromise brain phenotypes assessed at single time points. However, how maternal IL-6 associates with the trajectory of brain development remains unclear. We investigated whether maternal IL-6 levels during pregnancy relate to offspring amygdala volume development and anxiety-like behavior in Japanese macaques.

Interindividual Variability of Functional Connectivity in Awake and Anesthetized Rhesus Macaque Monkeys.

Background: Nonhuman primate (NHP) models are commonly used to advance our understanding of brain function and organization. However, to date, they have offered few insights into individual differences among NHPs. In large part, this is due to the logistical challenges of NHP research, which limit most studies to 5 subjects or fewer.

Newborn amygdala connectivity and early emerging fear.

Connectivity between the amygdala, insula (Amygdala-aI) and ventral medial prefrontal cortex (Amygdala-vmPFC) have been implicated in individual variability in fear and vulnerability to psychiatric disorders. However, it is currently unknown to what extent connectivity between these regions in the newborn period is relevant for the development of fear and other aspects of negative emotionality (NE), such as sadness. Here, we investigate newborn Am-Ins and Am-vmPFC resting state functional connectivity in relation to developmental trajectories of fear and sadness over the first two years of life using data from the Infant Behavior Questionnaire Revised (IBQ-R) and Early Childhood Behavior Questionnaire (ECBQ) (N=62).

How early media exposure may affect cognitive function: A review of results from observations in humans and experiments in mice.

Attention deficit hyperactivity disorder (ADHD) is now among the most commonly diagnosed chronic psychological dysfunctions of childhood. By varying estimates, it has increased by 30% in the past 20 years. Environmental factors that might explain this increase have been explored.

Delineating the Macroscale Areal Organization of the Macaque Cortex In Vivo.

Complementing long-standing traditions centered on histology, fMRI approaches are rapidly maturing in delineating brain areal organization at the macroscale. The non-human primate (NHP) provides the opportunity to overcome critical barriers in translational research. Here, we establish the data requirements for achieving reproducible and internally valid parcellations in individuals.

Excessive Sensory Stimulation during Development Alters Neural Plasticity and Vulnerability to Cocaine in Mice.

Early life experiences affect the formation of neuronal networks, which can have a profound impact on brain function and behavior later in life. Previous work has shown that mice exposed to excessive sensory stimulation during development are hyperactive and novelty seeking, and display impaired cognition compared with controls. In this study, we addressed the issue of whether excessive sensory stimulation during development could alter behaviors related to addiction and underlying circuitry in CD-1 mice.