Traumatic brain injury (TBI) causes a high rate of mortality and disability, and its treatment is still limited. Loss of neurons in damaged area is hardly rescued by relative molecular therapies. Based on its disease characteristics, we transplanted human embryonic stem cell-(hESC-) derived cerebral organoids in the brain lesions of controlled cortical impact-(CCI-) modeled severe combined immunodeficient (SCID) mice. Grafted organoids survived and differentiated in CCI-induced lesion pools in mouse cortical tissue. Implanted cerebral organoids differentiated into various types of neuronal cells, extended long projections, and showed spontaneous action, as indicated by electromyographic activity in the grafts. Induced vascularization and reduced glial scar were also found after organoid implantation, suggesting grafting could improve local situation and promote neural repair. More importantly, the CCI mice’s spatial learning and memory improved after organoid grafting. These findings suggest that cerebral organoid implanted in lesion sites differentiates into cortical neurons, forms long projections, and reverses deficits in spatial learning and memory, a potential therapeutic avenue for TBI.

The cerebral cortex forms early in development according to a series of heritable neurodevelopmental instructions. Despite deep evolutionary conservation of the cerebral cortex and its foundational six-layered architecture, significant variations in cortical size and folding can be found across mammals, including a disproportionate expansion of the prefrontal cortex in humans. Yet our mechanistic understanding of neurodevelopmental processes is derived overwhelmingly from rodent models, which fail to capture many human-enriched features of cortical development. With the advent of pluripotent stem cells and technologies for differentiating three-dimensional cultures of neural tissue in vitro, cerebral organoids have emerged as an experimental platform that recapitulates several hallmarks of human brain development.

Brain organoids are self-organizing tissue cultures grown from patient cell-derived induced pluripotent stem cells. They form tissue structures that resemble the brain in vivo in many ways. This makes brain organoids interesting for studying both normal brain development and for the development of neurological diseases. However, organoids have been poorly studied in terms of neuronal activity, as measured by electrical signals from the cells.

A team of scientists led by Dr. Thomas Rauen from the Max Planck Institute for Molecular Biomedicine in Münster, Germany, in collaboration with Dr. Peter Jones’ group at the NMI (Natural and Medical Sciences Institute at the University of Tübingen, Germany), has now developed a novel microelectrode array system (Mesh-MEA) that not only provides optimal growth conditions for human brain organoids, but also allows non-invasive electrophysiological measurements throughout the entire growth period. This opens up new perspectives for the study of various brain diseases and the development of new therapeutic approaches.

The study is published in the journal Biosensors and Bioelectronics.

When people lack visual imagination, this is known as aphantasia. Researchers from the University Hospital Bonn (UKB), the University of Bonn, and the German Center for Neurodegenerative Diseases (DZNE) investigated how the lack of mental imagery affects long-term memory.

They were able to show that changes in two important brain regions, the hippocampus, and the occipital lobe, as well as their interaction, have an influence on the impaired recall of personal memories in aphantasia. The study results, which advance the understanding of autobiographical memory, have now been published online by the specialist journal eLife.

Most of us find it easy to remember personal moments from our own lives. These memories are usually linked to vivid inner images. People who are unable to create mental images, or only very weak ones, are referred to as aphantasics. Previous neuroscientific studies have shown that the hippocampus, in particular, which acts as the brain’s buffer during memory formation, supports both autobiographical memory and visual imagination.

Year 2011 This brain wave replication can eventually lead to thought transfer or even downloading things like the matrix.

In an exclusive excerpt from his new book, a pioneering neuroscientist argues that brain-wave control of machines will allow the paralyzed to walk, and portends a future of mind melds and thought downloads.

By Miguel A. L. Nicolelis

When neurons strengthen their synapses, they “infect” surrounding cells with a virus-like protein to weaken those cells’ excitatory connections, according to a new preprint.