A few eternal questions:
- Is caffeine good for the brain?
- Does it boost cognitive functions?
- Does it protect against dementia?

There is little doubt that drinking that morning cup of coffee will likely increase alertness, but the main questions that research is trying to answer go beyond that. Basically: is there a sustained, lifetime, benefit or harm from drinking coffee regularly?

The answer, so far, contains good news and bad news. The good news for coffee drinkers is that most of the long-term results are directionally more positive than negative, so no clear harm seems to occur. The bad news is that it is not clear so far whether caffeine has beneficial effects on general brain functions, either short-term or long-term (aged-related decline or risks of dementia).

It is important to note that many of the studies showing an effect of coffee consumption on brain functions or risks of dementia report a correlation or association (they are not randomized clinical trials). As you know, correlation doesn’t prove causation: coffee drinkers may seem to do well in a number in these long-term studies, but there may be other reasons why coffee drinkers do better.

Q: How does caffeine affect my brain?
A: Caffeine is a stimulant.

It belongs to a chemical group called xanthine. Adenosine is a naturally occurring xanthine in the brain that slows down the activity of brain cells (neurons). To a neuron, caffeine looks like adenosine. It is therefore used by some neurons in place of adenosine. The result is that these neurons speed up instead of slowing down.

This increased neuronal activity triggers the release of the adrenaline hormone, which will affect your body Read the rest of this entry »

Welcome to the 70th edition of Encephalon, the blog carnival that offers some of the best neuroscience and psychology blog posts every other week.

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Mysteries of Brain and Mind

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On Neurons, Journeys, and Chemical Friends

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On Brain Functions

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Frontiers in Perception

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Next edition will be hosted by Neuroanthropology on Monday, May 25th. If you can’t wait until to read more, you may be interested in the new in-depth feature, Cognitive Monthly, offered by Cognitive Daily blog for $2/ month. This month’s issue, “The Illusion of Theater,” discusses the “remarkable science behind what theatrical professionals seem, to laypeople, to do intuitively: create an environment that encourages us to believe that what we see on stage is a true representation of reality.”

Michael I. Posner is a prominent scientist in the field of cognitive neuroscience. He is currently an emeritus professor of neuroscience at the University of Oregon (Department of Psychology, Institute of Cognitive and Decision Sciences). In August 2008, the International Union of Psychological Science made him the first recipient of the Dogan Prize “in recognition of a contribution that represents a major advance in psychology by a scholar or team of scholars of high international reputation.”

Dr. Posner, many thanks for your time today. I really enjoyed the James Arthur Lecture monograph on Evolution and Development of Self-Regulation that you delivered last year. Could you provide a summary of the research you presented?

I would emphasize that we human beings can regulate our thoughts, emotions, and actions to a greater degree than other primates. For example, we can choose to pass up an immediate reward for a larger, delayed reward.

We can plan ahead, resist distractions, be goal-oriented. These human characteristics appear to depend upon what we often call “self-regulation.” What is exciting these days is that progress in neuroimaging and in genetics make it possible to think about self-regulation in terms of specific brain-based networks.

Can you explain what self-regulation is?

All parents have seen this in their kids. Parents can see the remarkable transformation as their children develop the ability to regulate emotions and to persist with goals in the face of distractions. That ability is usually labeled ‘‘self-regulation.’’

The other main area of your research is attention. Can you explain the brain-basis for what we usually call “attention”?

I have been interested in how the attention system develops in infancy and early childhood.

One of our major findings, thanks to neuroimaging, is that there is not one single “attention”, but three separate functions of attention with three separate underlying brain networks: alerting, orienting, and executive attention. Read the rest of this entry »