Category Archives: Neuroscience

The shrinking human brain

This article has a lengthy discussion of the reasons why human brains seem to have been shrinking pretty dramatically over the past 5000 years. I think a few of the hypotheses presented may be combining, with nutrition during the period of civilization dawning being a strong candidate for having contributed.

But the hypothesis I find most compelling is the idea that as we have become domesticated. We have been selectively bred for low-aggression and living in close quarters. We might not have viewed our larger brained ancestors as smarter than us in any sense except for one: they could survive in the wild on their personal wits alone, without culture or having read a single word in their lifetimes.

via If Modern Humans Are So Smart, Why Are Our Brains Shrinking? | Human Evolution | DISCOVER Magazine.

How some brain cells hook up surprises researchers

The research helps move microglia up into the pantheon of brain cells known to affect brain signaling. Years ago, brain signaling was thought to be the exclusive domain of neurons. During the last two decades, scientists have found that astrocytes also have vast signaling networks. Now, microglia also seem to be an important player in the brain’s ability to adapt immediately and constantly to the environment and to shift its resources accordingly.

via How some brain cells hook up surprises researchers: The untold secret life of the humble microglia.

Neurons: Faster than thought and able to multiply

Not only does this theory explain why nerve cells process information much faster than previously thought. It also became clear that neurons do more than just add up pulses: In the decisive moments, they actually multiply. The availability of this mathematical operation, write the scientists, finally explains how the brain is able to execute complex computations. These insights in the basic processes of the brain will in turn inspire more powerful processor architectures in the future.

via Neurons: Faster than thought and able to multiply.

Brain is more chaotic than we realized

For every inch we go discovering how the brain works, another mile of mystery is uncovered.

The brain appears to process information more chaotically than has long been assumed. This is demonstrated by a new study conducted by scientists at the University of Bonn. The passing on of information from neuron to neuron does not, they show, occur exclusively at the synapses, i.e. the junctions between the nerve cell extensions. Rather, it seems that the neurons release their chemical messengers along the entire length of these extensions and, in this way, excite the neighbouring cells.

via Brain Works More Chaotically Than Previously Thought.