Efforts to study the development and function of the human cerebral cortex in health and disease have been limited by the availability of model systems. Extrapolating from our understanding of rodent cortical development, we have developed a robust, multistep process for human cortical development from pluripotent stem cells: directed differentiation of human embryonic stem (ES) and induced pluripotent stem (iPS) cells to cortical stem and progenitor cells, followed by an extended period of cortical neurogenesis, neuronal terminal differentiation to acquire mature electrophysiological properties, and functional excitatory synaptic network formation. We found that induction of cortical neuroepithelial stem cells from human ES cells and human iPS cells was dependent on retinoid signaling. Furthermore, human ES cell and iPS cell differentiation to cerebral cortex recapitulated in vivo development to generate all classes of cortical projection neurons in a fixed temporal order. This system enables functional studies of human cerebral cortex development and the generation of individual-specific cortical networks ex vivo for disease modeling and therapeutic purposes.

(via fuckyeahneuroscience)

Clint Eastwood might sound like an unlikely candidate to help investigate the evolution of the brain, but he has lent a helping hand to researchers doing just that. It turns out that brain regions that do the same job in monkeys and humans aren’t always found in the same part of the skull.

Previous studies comparing brains across species tended to assume that human brains were just blown-up versions of monkey brains and that functions are carried out by anatomically similar areas.

To test this idea, Wim Vanduffel of Harvard Medical School in Boston and the Catholic University of Leuven (KUL) in Belgium, and colleagues scanned the brains of 24 people and four rhesus monkeys while they watched The Good, The Bad and The Ugly. They compared the brain responses of each individual to the same sensory stimulation, and identified which brain areas had similar functions.

The majority of the human and monkey brain maps lined up, but some areas with a similar function were in completely different places.

The team say the discovery is crucial to building more accurate models of our evolution. “You can’t assume that because A and B are close together in the monkey brain, they need to be close together in the human brain,” Vanduffel says.

Noticing an elderly relative is suddenly starting to forget things, is getting confused or displaying sudden changes of mood are usually the first signs they are developing dementia.

But what if the disease could be spotted - and treatment given - years before any symptoms begin?

That’s the aim of researchers coming together in a new centre at University College London.

jfs1:

Channelopathy of calcium ion channels induces changes in neural firing, neurotransmitter (dopamine & norepinephrine) over-production, neuron proliferation, and gene expression. The results come from a study using neurons grown from Timothy-syndrome induced pluripotent stem cells (iPS cells) - modeling a psychiatric disease in a Petri dish. 

A neuron transplant has rewired damaged brain areas in mice, raising hopes that similar transplants might one day help to treat spinal-cord injuries, Parkinson’s disease and other brain conditions.

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(Medical Xpress) — Fully mature liver cells from laboratory mice have been transformed directly into functional neurons by researchers at the Stanford University School of Medicine. The switch was accomplished with the introduction of just three genes and did not require the cells to first enter a pluripotent state. It is the first time that cells have been shown to leapfrog from one fundamentally different tissue type to another.

The accomplishment extends previous research by the same group, which showed in 2009 that it is possible to directly transform mouse fibroblasts, or skin cells, into neurons.

“These liver cells unambiguously cross tissue-type boundaries to become fully functional neural cells,” said Marius Wernig, MD, PhD assistant professor of pathology and a member of Stanford’s Institute for Stem Cell Biology and Regenerative Medicine. “Even more surprising, these cells also simultaneously silence their liver-gene expression profile. They are not hybrids; they are completely switching their identities.”

The cells make the change without first becoming a pluripotent type of stem cell — a step long thought to be required for cells to acquire new identities.

(Source: fuckyeahneuroscience)

Neural stem cells are capable of self-renewal and can generate neurons, astrocytes and oligodendrocytes. During nervous system development, NSCs within the primitive neural ectoderm give rise to neural progenitors, which rapidly become regionally and temporally specified, first generating large projection neurons and later small interneurons and glia. Small numbers of NSCs persist in the adult brain. They proliferate slowly and produce new neurons throughout life to replenish cells in the hippocampus and olfactory bulb. NSCs and progenitor cells can be isolated from embryonic stem cells, induced pluripotent stem cells, and fetal and adult brain samples. They can be induced to differentiate into neurons and glia in vitro and in vivo. NSCs grown in culture allow in vitro modeling of nervous system development and diseases. NSCs are also under investigation as potential therapeutic agents for neurodegenerative diseases and nervous system injury.

Follow link for pdf of wall chart.

Lesbian and heterosexual women respond differently to specific human odours, a brain-scanning study has found. The homosexual women showed similar brain activity to heterosexual men when they inhaled certain chemicals, which may be pheromones, the researchers say.