Cerebral Hemispheres 2
NEUROSCIENTIFICALLY CHALLENGED

NEUROSCIENCE MADE SIMPLER

I Have the Strangest Feeling I’ve Written this Post Before


We’ve all experienced it, some of us many times in many different places: déjà vu, that nebulous feeling you’ve been somewhere before although you can’t pinpoint exactly when or under what circumstances. A number of explanations have been offered over the years for why déjà vu occurs. They range from the mystical (remnants of memories from a past life) to the scientific. Even within these disparate categories the explanations are numerous. Some scientists consider it simply a case of erroneous memory. Perhaps, they suggest, some features of the environment are similar enough to a past environment to create a sense of familiarity, even though it is inaccurate. Others postulate déjà vu results from a lack of calibration between short and long-term memory. This might occur when the details of a scene are sent to long-term memory storage before they have been consciously processed. Thus, there is a lag of a few seconds before the short-term memory catches up, when a distant memory of the present environment seems to exist even though it was formed just seconds prior. Most of the scientific explanations, although they vary in details, share the implication that déjà vu involves some sort of miscalculation or misrepresentation by the brain.

Current research involving deep brain stimulation (DBS) may eventually provide some real insight into déjà vu, although déjà vu had nothing to do with the original goals of the research. DBS is a relatively new technique where a device that emits electrical pulses is surgically implanted in the brain. Although the reasons for its effectiveness are not fully understood, it has been shown to be beneficial in the treatment of Parkinson’s disease, tremors, and chronic pain. Andres Lozano, a Professor of Neurosurgery at the Toronto Western Hospital in Toronto, Ontario, and his team of researchers were attempting to use DBS to treat a 50-year old male patient with chronic obesity when they induced an unexpected result. While electrically stimulating areas of the hypothalamus in the hopes of identifying a site with appetite-suppressant qualities they discovered an area near the fornix that elicited feelings of déjà vu. With further stimulation the patient was able to recall vivid memories of being in a park with his friends when he was around twenty years old. The patient returned for further tests and it was found stimulation of the same area increased performance on memory tasks.

The hypothalamus is primarily involved in the regulation of metabolic and other autonomic processes through its connection to the pituitary gland. The fornix, however, has a more prominent role in memory. It is made up of a bundle of axons (nerve fibers) that connect to the hippocampus, an area of the brain thought to be extremely important in memory formation and recall.

Probably the most interesting aspect of these findings has little to do with déjà vu and more to do with DBS. DBS has only begun to be implemented within the past ten years or so, and it continues to surprise scientists and doctors with its multifarious uses. In addition to its efficacy in alleviating the chronic conditions listed above, it has also been found to have some success (just within the past year) in rousing patients from a comatose state. Since we still don’t know why this procedure is effective, imagine its potential benefit when we figure out what the mechanism of action is.

YOUR BRAIN, EXPLAINED

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.

  • 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

  • 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

BIZARRE

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.

  • 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

  • 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

  • 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

  • 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