Scientific Illustration

auxcheveuxlongs:

Scientific Illustration in the Field of Neuroscience

tarartara:

Art inspired by Neuroscience. Cajal.

neurosciencestuff:

Detrimental effect of obesity on lesions associated with Alzheimer’s disease

Researchers from Inserm and the Université Lille/Université Lille Nord de France have recently used a neurodegeneration model of Alzheimer’s disease to provide experimental evidence of the relationship between obesity and disorders linked to the tau protein. This research was conducted on mice and is published in the Diabetes review: it corroborates the theory that metabolic anomalies contribute massively to the development of dementia.

In France, more than 860,000 people suffer from Alzheimer’s disease and related disorders, making them the largest cause of age-related loss of intellectual function. Cognitive impairments observed in Alzheimer’s disease result from the accumulation of abnormal tau proteins in nerve cells undergoing degeneration (see the picture below). We know that obesity, a major risk factor in the development of insulin resistance and type 2 diabetes, increases the risk of dementia during the aging process. However, the effects of obesity on ‘Taupathies’ (i.e. tau protein-related disorders), including Alzheimer’s disease, were not clearly understood. In particular, researchers assumed that insulin resistance played a major role in terms of the effects of obesity.

The “Alzheimer & Tauopathies” team from mixed research unit 837 (Inserm/Université Lille 2/Université Lille Nord de France) directed by Dr. Luc Buée, in collaboration with mixed research unit 1011 “Nuclear receptors, cardiovascular diseases and diabetes”, have just demonstrated, in mice, that obese subjects develop aggravated disorders. To achieve this result, young transgenic mice, who develop tau-related neurodegeneration progressively with age, were put on a high-fat diet for five months, leading to progressive obesity.

“At the end of this diet, the obese mice had developed an aggravated disorder both from the point of view of memory and modifications to the Tau protein”, explains David Blum, in charge of research at Inserm.

This study uses a neurodenegeneration model of Alzheimer’s disease to provide experimental evidence of the relationship between obesity and disorders linked to the tau protein. Furthermore, it indicates that insulin resistance is not the aggravating factor, as was suggested in previous studies.

“Our research supports the theory that environmental factors contribute massively to the development of this neurodegenerative disorder” underlines the researcher. “Our work is now focussing on identifying the factors responsible for this aggravation” he adds.

jtotheizzoe:

How do we know that there are 100 billion neurons in the brain?

The brain is a tangled web of cells, most of which are frustratingly transparent, whose axons are interwoven like a oblong pile of snakes the size of several thousand Olympic swimming pools. Counting them is clearly a significant challenge. Where did that “100 billion” number come from?

It’s a little bit of guesstimation combined with a healthy dose of educated extrapolation. That number, which is now thought to be closer to 86 billion, is complicated by the fact that the brain contains lots of cells that aren’t neurons (like glia). The brain also isn’t uniformly packed with nerve cells, with some areas containing many times more than others. 

Old methods relied on staining a slice of brain with a dye that randomly colors nerve cells (like the Golgi method illustrated above by Santiago Ramón y Cajal). You calculate the number in the whole slice, then count slices from different areas of the brain, do some mathematical gymnastics, carry the 2 and get a number like 100 billion.  

The newest method, which counted the number of nerve nuclei in a chunk of brain, is much more accurate, but still involves lots of guesswork. But in the end, the number of neurons isn’t nearly as important as how they are organized. An elephant brain weighs more than four times our own, but it’s the map that makes us man.  

(via EyeWire)

thenearsightedmonkey:

medicalschool:

Pyramidal Neuron, drawn by Santiago Ramón y Cajal (1852-1934)

“For example, in 2005, neuroscientists discovered that an epilepsy patient had one neuron cell that fired whenever a photo of Jennifer Aniston was presented. Various photos showing the blonde actress in different poses and from different angles all elicited a response from the same concept cell, a neuron in the hippocampus.

“Concept cells were also found in different regions of the medial temporal lobe,” Roy said. “For example, a ‘James Brolin cell’ was found in the right hippocampus, a ‘Venus Williams cell’ was in the left hippocampus, a ‘Marilyn Monroe cell’ was in the left parahippocampal  cortex and a ‘Michael Jackson cell’ was in the right amygdala.”

Except from: Do brain cells need to be connected to have meaning?
December 4, 2012 by Lisa Zyga in Neuroscience

(via mudwerks)

kitesh:

“Santiago Ramón y Cajal was a Spanish pathologist, histologist,neuroscientist, and Nobel laureate. His pioneering investigations of the microscopic structure of the brain were original: he is considered by many to be the father of modern neuroscience. He was skilled at drawing, and hundreds of his illustrations of brain cells are still used for educational purposes today.

As a child he was transferred between many different schools because of his poor behavior and authoritarian attitude. An extreme example of his precociousness and rebelliousness is his imprisonment at the age of eleven for destroying the town gate with a homemade cannon.”

(via kitesh-deactivated20121209)

ulaulaman:

Highlights of Einstein’s brain

A new study described some unique features of Albert Einstein’s brain. More details on my post, Albert Einstein’s unusual brain

from: Falk D., Lepore F.E. & Noe A. (2012). The cerebral cortex of Albert Einstein: a description and preliminary analysis of unpublished photographs, Brain, DOI: 10.1093/brain/aws295

liveactivedrm:

W. & A. K. Johnston’s Charts of Anatomy and Physiology

By Dr. Wm. Turner, Professor of Anatomy, University of Edinburgh
(Now Sir William Turner, Prinicipal of the University of Edinburgh)

sagansense:

What Happens to the Brain When the Mind is at Rest?

Whether daydreaming or mediating, it’s normal—even unavoidable—that our minds relax a little now and then. And over the last few years, scientists have begun examining what a brain at rest looks like in MRI scans: “Some circuits must remain active; they control automatic functions such as breathing and heart rate. But much of the rest of the brain continues to chug away as the mind naturally wanders…” During inactive states, blood flow to the brain dips just 5-10% compared to when researchers are running task-based experiments that require subjects to concentrate on a specific target.

What’s the Big Idea?

Resting states have been shown to be an important stage in creative processes, allowing the mind to introduce and consolidate seemingly unrelated material to the question at hand. Scientists behind brain imaging research speculate on other possible functions: “Resting activity might be keeping the brain’s connections running when they are not in use. Or it could be helping to prime the brain to respond to future stimuli, or to maintain relationships between areas that often work together to perform tasks. It may even consolidate memories or information absorbed during normal activity.”

Photo credit: Shutterstock.com

Dr. Joy Hirsch
Neuroscientist, Columbia University

(via ohyeahdevelopmentalbiology)