Neurotransmitters and brain function

Although I’ve taken a general interest in brain function and states of consciousness, until the last few years I really only paid much attention to the relationship between brain waves and states of consciousness, and in particular the use of brainwave entrainment methods to facilitate certain states (see earlier post here). Only in the last few years have I looked more closely into the complex and interacting roles of brain waves, neurotransmitters and various brain networks.

By Thomas Splettstoesser (www.scistyle.com), https://commons.wikimedia.org/w/index.php?curid=41349083

Neurons (nerve cells) in the brain form elaborate networks, with each neuron having up to 15,000 connections with neighbouring neurons at contact points called synapses. While the nerve impulse travel through the neuron as an electrical impulse, it does not cross the gap known as the synaptic cleft but rather stimulates the release of a chemical messenger: a neurotransmitter. This crosses the synaptic cleft and is received by neurotransmitter receptors on the target cell. A neurotransmitter with increase (excitatory) or decrease (inhibitory) the probability that the target cell will produce a nerve impulse.

There are three main types of neurotransmitters in the brain: small molecules used for fast signal transmission between neurons, small used for slower modulation of network activity, and large molecules (peptides) used for even slower modulation of cell circuit functions. Most neurons have receptors for most of the neurotransmitters in all three of these categories.

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The 10 greatest athletic feats of the 21st century – transcending perceived limits of mind and body

I have been following Eliud Kichoge’s bid to be the first human to run a marathon in less than 2 hours. He succeeded on Saturday with a time of 1 hour 59 mins and 40 seconds. This is an absolutely extraordinary achievement. It was not an official world record, because of the use of rotating pacemakers and because Kipchoge was handed his drinks from a bike, but it is still the fastest marathon ever run. After he finished, Kipchoge said that he had wanted to send a message to the world that no human is limited.

This made me think about a number of extraordinary feats that I’ve seen achieved in recent years and I decided to make a list of my top 10 most extraordinary human achievements in the realm of extreme feats that broke barriers and went beyond perceived limits of mind and body. Quite a few of these feats involve non-ordinary states of consciousness that need total engagement in the here-now, unity of mind and body, and transcendence of distracting thoughts and emotions. States known as “being in the zone” or “flow” to athletes, as “immovable mind” to the samurai and as samadhi to Zen practitioners.

I also decided arbitrarily to restrict my list to feats achieved in the last 20 years, or in other words, in the 21st century (counting the year 2000 as part of this century). This is an idiosyncratic list that reflects my interests and the level of amazement and awe that watching (or in one case reading an account of) the event inspired in me. You may well have a very different list, though I think at least the ones towards the top should be on most lists.

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