The evolution of the field of neuroscience has been propelled by the advent of novel technological capabilities, and the pace at which these capabilities are being developed has accelerated ...dramatically in the past decade. Capitalizing on this momentum, the United States launched the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative to develop and apply new tools and technologies for revolutionizing our understanding of the brain. In this article, we review the scientific vision for this initiative set forth by the National Institutes of Health and discuss its implications for the future of neuroscience research. Particular emphasis is given to its potential impact on the mapping and study of neural circuits, and how this knowledge will transform our understanding of the complexity of the human brain and its diverse array of behaviours, perceptions, thoughts and emotions.
Increasingly, national governments across the globe are prioritizing investments in neuroscience. Currently, seven active or in-development national-level brain research initiatives exist, spanning ...four continents. Engaging with the underlying values and ethical concerns that drive brain research across cultural and continental divides is critical to future research. Culture influences what kinds of science are supported and where science can be conducted through ethical frameworks and evaluations of risk. Neuroscientists and philosophers alike have found themselves together encountering perennial questions; these questions are engaged by the field of neuroethics, related to understanding of the nature of the self and identity, the existence and meaning of free will, defining the role of reason in human behavior, and more. With this Perspective article, we aim to prioritize and advance to the foreground a list of neuroethics questions for neuroscientists operating in the context of these international brain initiatives.
Neuroscience is a national priority across the globe necessitating engagement with the underlying cultural and ethical values that drive brain research. We offer a list of neuroethics questions for neuroscientists to advance and accelerate an ethically tenable globalized neuroscience.
Iron deficiency early in life is associated with cognitive disturbances that persist beyond the period of iron deficiency. Within cognitive processing circuitry, the hippocampus is particularly ...susceptible to insults during the perinatal period. During the hippocampal growth spurt, which is predominantly postnatal in rodents, iron transport proteins and their messenger RNA stabilizing proteins are upregulated, suggesting an increased demand for iron import during this developmental period. Rat pups deprived of iron during the perinatal period show a 30-40% decrease in hippocampal metabolic activity during postnatal hippocampal development. We hypothesized that this reduced hippocampal neuronal metabolism impedes developmental processes such as neurite outgrowth. The goals of the current study were to investigate the effects of perinatal iron deficiency on apical dendritic segment growth in the postnatal day (P) 15 hippocampus and to determine if structural abnormalities persist into adulthood (P65) following iron treatment. Qualitative and quantitative immunohistochemical analyses of dendritic structure and growth using microtubule-associated protein-2 as an index showed that iron-deficient P15 pups have truncated apical dendritic morphology in CA1 and a persistence of an immature apical dendritic pattern at P65. These results demonstrate that perinatal iron deficiency disrupts developmental processes in the hippocampal subarea CA1 and that these changes persist despite iron repletion. These structural abnormalities may contribute to the learning and memory deficits that occur during and following early iron deficiency.
The evolution of the field of neuroscience has been propelled by the advent of novel technological capabilities, and the pace at which these capabilities are being developed has accelerated ...dramatically in the past decade. Capitalizing on this momentum, the United States launched the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative to develop and apply new tools and technologies for revolutionizing our understanding of the brain. In this article, we review the scientific vision for this initiative set forth by the National Institutes of Health and discuss its implications for the future of neuroscience research. Particular emphasis is given to its potential impact on the mapping and study of neural circuits, and how this knowledge will transform our understanding of the complexity of the human brain and its diverse array of behaviours, perceptions, thoughts and emotions.
We designed a model of early iron deficiency (ID) in the rodent that mimicked human conditions of fetal/early postnatal ID and assessed hippocampal dendritic growth and electrophysiological function ...both during the period of ID (P15, P30) and following iron rehabilitation (P65). In our models of early ID, the hippocampus demonstrated a greater percentage of iron concentration loss than the total brain at P15, suggesting increased hippocampal vulnerability during this developmental period. Qualitative and quantitative immunohistochemical analyses of dendritic structure and growth demonstrated iron deficient pups to display truncated apical dendritic morphology in CA1 at P15 and a persistence of an immature apical dendritic pattern at P65. We then assessed hippocampal function and plasticity by investigating basal synaptic transmission, paired-pulse facilitation (PPF), and long-term potentiation (LTP) at Schaffer collateral-CA1 synapses. While the iron sufficient control pups demonstrated an increase in synaptic strength across development, iron deficient pups demonstrated no developmental increase in either basal synaptic function or PPF between P15 and P65. Furthermore, repletion of iron status did not produce significant changes in the formerly iron deficient group's developmental trajectory indicating long-term or permanent changes within the mechanisms producing these electrophysiological responses. Expression of LTP, an established biological substrate of learning and memory, from iron deficient pups did not differ from iron sufficient pups at P15, but iron deficient slices failed to demonstrate a decrease in LTP expression from P15 to P30. After iron repletion, LTP expression was lower in the iron deficient group at P65. Thus, early ID delays and/or abolishes the developmental maturation of structural and electrophysiological components of synaptic efficacy and plasticity.
PDF
