Cerebral Hemispheres 2


Beta-Blockers May Act on the Brain

When beta-blockers were discovered, they held such promise that the National Heart, Lung, and Blood Institute (NHLBI) halted trials of one such drug nine months early. They felt it was unethical to continue administering placebos to the control group in the study, based on the significantly improved survival rates they were seeing among those who were taking the beta-blockers. By the late 1990s beta-blockers had become a standard facet of therapy for patients suffering from congestive heart failure. They can be a very effective form of treatment, correlating with significantly reduced mortality rates in congestive heart failure patients.

Beta-blockers are so called because they block the action of epinephrine and norepinephrine on beta-adrenergic (BA) receptors. Epinephrine and norepinephrine are better known to some as adrenaline and noradrenaline. They are hormones responsible for modulating the “fight or flight” response of an organism. This response occurs when an organism is faced with a stressful situation, and results in an increase in both heart rate and force of myocardial contraction, along with the constriction of blood vessels in many parts of the body. Understandably, this puts a strain on the heart, a strain which beta-blockers seem to mitigate by blocking adrenaline from binding to BA receptors and reducing the intensity of the fight or flight response.

BA receptors are located throughout the body, however, and it has never been completely understood exactly where beta-blockers work to improve heart health. It was assumed (although not proven) that most of their action was on receptors in the heart. It was thought that the antagonistic effects of beta-blockers on these receptors inhibited the action of epinephrine, lowering heart rate, dilating blood vessels, and thus having an antihypertensive effect.

But a group of researchers at University College London recently demonstrated that beta-blockers may also have an influence on areas of the brain that regulate heart function. They studied the brains of rats that underwent infarction-induced heart failure and found the beta-blocker metoprolol acted directly on the brain to slow that heart failure. The location of the action was in an area the group had previously found to be associated with blood pressure and heart rate.

This doesn’t mean beta-blockers don’t work on the heart as well. It does, however, provide an impetus for further research into their mechanism. For, if they do have an effect on the central nervous system, understanding that influence could open the door for more comprehensive, and perhaps more specific, therapies to treat congestive heart failure, and heart disease in general.


Sleep. Memory. Pleasure. Fear. Language. We experience these things every day, but how do our brains create them? Your Brain, Explained is a personal tour around your gray matter. Building on neuroscientist Marc Dingman’s popular YouTube series, 2-Minute Neuroscience, this is a friendly, engaging introduction to the human brain and its quirks using real-life examples and Dingman’s own, hand-drawn illustrations.

  • An informative, accessible and engaging book for anyone who has even the slightest interest in how the brain works, but doesn’t know where to begin. - Dean Burnett, PhD, author, Happy Brain and Idiot Brain

  • Dingman weaves classic studies with modern research into easily digestible sections, to provide an excellent primer on the rapidly advancing field of neuroscience. - Moheb Costandi, author, Neuroplasticity and 50 Human Brain Ideas You Really Need to Know

  • ...a highly readable and accessible introduction to the operation of the brain and current issues in neuroscience... a wonderful introduction to the field. - Frank Amthor, PhD, Professor of Psychology, The University of Alabama at Birmingham, author, Neuroscience for Dummies

  • Reading like a collection of detective stories, Your Brain, Explained combines classic cases in the history of neurology with findings stemming from the latest techniques used to probe the brain’s secrets. - Stanley Finger, PhD, Professor Emeritus of Psychological & Brain Sciences, Washington University (St. Louis), author, Origins of Neuroscience


This book shows a whole other side of how brains work by examining the most unusual behavior to emerge from the human brain. In it, you'll meet a woman who is afraid to take a shower because she fears her body will slip down the drain, a man who is convinced he is a cat, a woman who compulsively snacks on cigarette ashes, and many other unusual cases. As uncommon as they are, each of these cases has something important to teach us about everyday brain function.

  • Bizarre is a collection of stories of how the brain can create zombies, cult members, extra limbs, instant musicians, and overnight accents, to name a few of the mind-scratching cases. After reading this book, you will walk away with a greater appreciation for this bizarre organ. If you are a fan of Oliver Sacks' books, you're certain to be a fan of Dingman's Bizarre. - Allison M. Wilck, PhD, Researcher and Assistant Professor of Psychology, Eastern Mennonite University

  • Through case studies of both exceptional people as well as those with disorders, Bizarre takes us on a fascinating journey in which we learn more about what is going on in our skull. - William J. Ray, PhD, Emeritus Professor of Psychology, The Pennsylvania State University, author, Abnormal Psychology

  • Dingman brings the history of neuroscience back to life and weaves in contemporary ideas seamlessly. Readers will come along for the ride of a really interesting read and accidentally learn some neuroscience along the way. - Erin Kirschmann, PhD, Associate Professor of Psychology & Counseling, Immaculata University

  • A unique combination of storytelling and scientific explanation that appeals to the brain novice, the trained neuroscientist, and everyone in between. Dingman explores some of the most fascinating and mysterious expressions of human behavior in a style that is case study, dramatic novel, and introductory textbook all rolled into one. - Alison Kreisler, PhD, Neuroscience Instructor, California State University, San Marcos