Monday, 11 March 2013
Free Radicals and Aging: More Complicated Than We Thought
In 2010, Dr. Siegfried Hekimi and his colleagues at McGill University in Montreal received a great deal of media coverage for their research showing that antioxidants, which many people take as food supplements to fight the damaging effects of free radicals, not only do not slow down the aging process but on the contrary might actually accelerate it. Even more unbelievably, when the researchers used Caenorhabditis elegans, a species of small worms, as an animal model and exposed them to an herbicide that is toxic to humans and generates a lot of free radicals, these worms lived 60% longer than worms who were not exposed to it! (more…)
Monday, 4 March 2013
Remembering Every Day of Your Life
Thanks to your episodic memory, you can easily remember what you ate yesterday or what you did last weekend. But if you try to go back a few weeks or months, or especially a few years, you’ll see that you’ve lost most of your autobiographical memories, except possibly for a few events with a strong emotional impact. Instead, your semantic memory will have taken over, generalizing from the recurrent features of your life to develop abstract concepts—and that is as it should be.
But a very small number of people (about 20 have been identified to date) have highly superior episodic memories that let them recall what they did on virtually any specific day in their lives, 10, 20, or even 30 years later! (more…)
Memory and the Brain | Comments Closed
Monday, 25 February 2013
Links on Pleasure-Seeking Behaviour
This week, as I have before in this blog, I am posting a set of new links to other web sites that discuss a subject covered in The Brain from Top to Bottom. The subject this week is the sub-topic “Pleasure-Seeking Behaviour”, under the topic “Pleasure and Pain”. For each link, I also provide a brief description of the content on the site in question. (more…)
Pleasure and Pain | Comments Closed
Monday, 18 February 2013
4 New RSS Feeds for Recent News About the Brain
As you may have noticed, last week we added a new feature to The Brain from Top to Bottom Blog to help you follow the latest news in the vast field of neuroscience. I’m talking about the four RSS feeds now appearing in the left-hand column under the heading “RECENT NEWS ABOUT THE BRAIN”. (more…)
From the Simple to the Complex | Comments Closed
Monday, 11 February 2013
Neurons with Surprising Properties
Just when scientists thought they had a pretty good understanding of how neurons communicate, along comes a new set of seemingly abnormal data that overturn the official paradigm (such upheavals are not uncommon in the world of science). Any good neuroscience textbook will tell you that neurons are stimulated or inhibited by input signals that they receive through the synapses between their dendrites or cell bodies and other neurons. As a neuron receives all these signals, it integrates them, and then fires one or more action potentials into its axon. These action potentials travel down to the tip of the axon, where they cross synapses to other neurons, and so on.
But as a team of researchers from Northwestern University, in Illinois in the United States, discovered and reported in the February 2011 issue of Nature Neuroscience, the process just described is clearly not the only way that nerve impulses travel through neurons. (more…)
From the Simple to the Complex | Comments Closed
