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Neuroscience of the Nonconscious Mind Neuroscience of the Nonconscious Mind Rajendra D. Badgaiyan ChiefofPsychiatry, SouthTexasVeteran Health CareSystem, San Antonio, TX,UnitedStates Professor of Psychiatry, Joe &Teresa Lozano Long Schoolof Medicine, University of TexasHealthScience Center, San Antonio, TX,UnitedStates AcademicPressisanimprintofElsevier 125LondonWall,LondonEC2Y5AS,UnitedKingdom 525BStreet,Suite1650,SanDiego,CA92101,UnitedStates 50HampshireStreet,5thFloor,Cambridge,MA02139,UnitedStates TheBoulevard,LangfordLane,Kidlington,OxfordOX51GB,UnitedKingdom Copyright©2019ElsevierInc.Allrightsreserved. Nopartofthispublicationmaybereproducedortransmittedinanyformorbyanymeans, electronicormechanical,includingphotocopying,recording,oranyinformationstorageand retrievalsystem,withoutpermissioninwritingfromthepublisher.Detailsonhowtoseek permission,furtherinformationaboutthePublisher’spermissionspoliciesandour arrangementswithorganizationssuchastheCopyrightClearanceCenterandtheCopyright LicensingAgency,canbefoundatourwebsite:www.elsevier.com/permissions. Thisbookandtheindividualcontributionscontainedinitareprotectedundercopyrightbythe Publisher(otherthanasmaybenotedherein). Notices Knowledgeandbestpracticeinthisfieldareconstantlychanging.Asnewresearchand experiencebroadenourunderstanding,changesinresearchmethods,professionalpractices,or medicaltreatmentmaybecomenecessary. Practitionersandresearchersmustalwaysrelyontheirownexperienceandknowledgein evaluatingandusinganyinformation,methods,compounds,orexperimentsdescribedherein. Inusingsuchinformationormethodstheyshouldbemindfuloftheirownsafetyandthesafety ofothers,includingpartiesforwhomtheyhaveaprofessionalresponsibility. Tothefullestextentofthelaw,neitherthePublishernortheauthors,contributors,oreditors, assumeanyliabilityforanyinjuryand/ordamagetopersonsorpropertyasamatterof productsliability,negligenceorotherwise,orfromanyuseoroperationofanymethods, products,instructions,orideascontainedinthematerialherein. BritishLibraryCataloguing-in-PublicationData AcataloguerecordforthisbookisavailablefromtheBritishLibrary LibraryofCongressCataloging-in-PublicationData AcatalogrecordforthisbookisavailablefromtheLibraryofCongress ISBN:978-0-12-816115-9 ForInformationonallAcademicPresspublications visitourwebsiteathttps://www.elsevier.com/books-and-journals Publisher:NikkiLevy AcquisitionEditor:JoslynChaiprasert-Paguio EditorialProjectManager:PatGonzalez ProductionProjectManager:SujathaThirugnanaSambandam CoverDesigner:MatthewLimbert TypesetbyMPSLimited,Chennai,India Preface Scientific study of consciousness began a few years ago. Although many laboratories are trying to understand its biological basis, nobody knows for sure what consciousness means in scientific terms. So, how can we study a phenomenon that cannot even be defined and why it is so difficult to define something that almost everybody—scientists and nonscientists alike—knows about? That is precisely the problem. We all know what consciousness is, but everybody has a different definition for it and science requires a defini- tion that is logical and acceptable to the scientific community. That has not happened sofar. Can we really talk about the nonconscious mind yes, if we do not have an acceptable definition of consciousness? The answer is, we can, but we have to first agree on what the nonconscious mind is. In this book, I have used the “common sense” definition of both terms: “nonconscious” and “mind.” We use the term nonconscious to describe all actions that we perform without being consciously aware of them. For example, moving legs while walking and moving fingers while typing. We are aware of walking and typing but not of taking each step forward or moving each finger to tap akey—unlessyouarewalkingortypingfortheveryfirsttime!Severalother examples will be discussed in the following chapters. For actions like these, we will not use the term unconscious even though many philosophers, cogni- tive scientists, textbooks, and almost all of the older literatures have used the terms nonconscious and unconscious interchangeably. I make a distinction between these terms. I also consider a task nonconscious if it is performed without conscious awareness even if a person is otherwise conscious. While we are not usually consciously aware of movements we make while walking and typing, we perform those actions under full consciousness. We are however, able to voluntarily control some of those functions (but not all). In these cases the function is no longer nonconscious. For example, while typing we can con- sciouslymovefingerstorespectivekeysandwhilewalkingmovelegsatwill to take each step but if we do so these functions are no longer nonconscious ones.Afunctioncanthereforebebothconsciousandnonconsciousdepending on how it is performed. Unconscious, on the other hand, refers to a state in whichapersonisincapableofperformingataskatwill.Forexample,anindi- vidualundergeneralanesthesiaorinacomaisincapableofperformingatask vii viii Preface at will. We make this distinction because the neural networks involved in processing are different under nonconscious and unconscious conditions. Since many researchers have not made a distinction between the terms nonconscious,unconscious,andsometimesthesubconscious,wehavetriedto use their original terminology in this text to avoid distorting their meanings. However, we only discuss those concepts of the “subconscious” and “uncon- scious” mind that are similar to the above definition of the nonconscious mind. Mind is another term we need to define. In the context of this book this term refers to higher mental functions like memory, attention, language, and executive processing. We have also included emotion, extrasensory percep- tion, decision making, dreams, and hypnosis under the broad definition of mind. While we I will talk about consciousness but will not discuss the soul. I do not know what the soul is neurobiologically, and cannot even guess whether itexists inthe neuroscience domain. Now coming back to nonconscious mental tasks, I have been asked numerous times in formal scientific meetings and in informal gatherings how can we perform a mental task without being aware of it. Are not we aware of what we do? The answer is no. We perform mental functions more often without conscious awareness than with awareness. I say this with a strong conviction because all conscious actions include some form of nonconscious mental processing. For example, conversation requires conscious action to decide the subject matter, but modulation of voice, selection of the words, grammar, and syntax that goes with it are processed nonconsciously. Nonconscious processes put the conversation in the right context, recall past experiences, retrieve memories of linguistic learning, and select appropriate wordstouse.Thus,agreatdealofnonconsciousprocessingisneededtoexe- cute seemingly simpleconscious tasks. For another example, try to remember how many times you drove a car on a familiar route while enjoying music, talking on the phone, or simply thinking about work or home? How many times were you unable to recall something on or around the road? Probably many times. So, what is happen- ing here? We drive consciously but still do not remember everything such as when we applied the breaks or moved the steering wheel. This means the brain must have processed everything that was on the road and also recalled driving lessons and traffic rules. Since driving involves complex information processing both at spatial and temporal levels, we process information skill- fully at a very high level while driving, but do not remember most driving events. How is this possible? There are many possible reasons: one, stimuli wereprocessedwithoutawareness;two,theywereprocessedwithfullaware- ness but quickly vanished from memory; three, perception never entered memory; and four, memories of stimuli were not retrievable. These possibili- ties sometimes make it difficult to understand the neural processing of Preface ix nonconscious mind. Any of the above possibilities could account for proces- sing ofinformation withoutawareness. In our daily lives, we perform many functions, withoutconsciouslyaware of them. While changing clothes, while typing and walking, as mentioned above, etc. Similarly, we walk with full conscious awareness but we do not remember every step and every pot hole or rock avoided. So do we need to be consciouslyaware of a stimulus before processing and responding toit, or does the brain do it for us? After all, the brain controls vital processes like circulation and respiration without our conscious awareness. It also makes changes such as increasing heart rate during exercise, for example. Of course, we can control some of these processes like respiration but only within limits. We cannot voluntarily stop breathing indefinitely! In this context, it is also reasonable to ask whether the brain controls cognition, behavior, emotion and all of our actions nonconsciously and provides us limited ability to modify them at will? I think there is no reason to believe why it might notbe the case. Most of our actions are probablyexecuted non- consciously without our knowledge and without conscious awareness. It is therefore important tounderstand nonconscious mind. In the following chapters I have discussed how the nonconscious mind makes us smarter and more resilient and how it provides survival benefits. It does not mean the conscious mind is not important. It is. There is a place for both. In the book I have discussed how the conscious and nonconscious mind interact tomakeus the resilientand intelligent species we are. Chapter 1 Historical perspective It is indeed surprising that we do not have acceptable definitions of the con- scious and nonconscious mind even though these concepts were developed thousands of years ago in ancient civilization. Ancient Indian literature, the Vedas, which originated in oral form around 4000 BCE (but scripted around 1500 BCE) have detailed descriptions of the conscious and nonconscious mentalfunctions.1Theseconcepts,however,remainedunappreciatedforcen- turiespossiblybecausescriptureswereinSanskrit,anoldanddeadlanguage. The Vedas have now been translated into many languages. The basic con- cepts of consciousness described in Vedas are as relevant today as they were centuries ago. The following is a brief snapshot of those concepts. I have spelled Sanskrit words to sound as close to the original phonation as possible. Therefore, spellings in this book may differ from those used by other authors. Additionally, because ancient Indian scriptures evolved over centu- ries, there are several versions and schools of thought with slightly different concepts. For the sake of simplicity I have discussed only those concepts that are accepted by most scholars. Vedas are a collection of many scriptures and the word literally means “knowledge” in Sanskrit. Therefore Vedas are considered books ofknowledge. The Vedas describe two forms of consciousness: universal consciousness called brahman and personal consciousness called atman.1(cid:1)3 These two forms are practically indistinguishable because atman is a part of brahman (Fig. 1.1). There is only one brahman but each individual has atman. Therefore there isnodifference inatmanoftwopeople.Itimpartsbasiccon- sciousness, which is same in all members of the human species. What distin- guishes people is their inner self or antahkaran, which is a form of atman. This inner self has four components: ahankar (ego), buddhi (intellect), manas (senses), and chitta (mind). Further, chitta or mind consists of five entities: jagrat chitta (wakeful consciousness), sanskar chitta (subconscious mind), vasana chitta (subsubconscious mind), karan chitta (superconscious mind), and anukaran chitta (subsuperconscious mind). Thus Vedic literature describes two forms of nonconscious mind: sanskar chitta and vasana chitta. Sanskar is the upper layer of subconscious and is a stage just beneath con- scious layer. It is supposed to be a repository of past experience. Vasana NeuroscienceoftheNonconsciousMind.DOI:https://doi.org/10.1016/B978-0-12-816115-9.00001-2 ©2019ElsevierInc.Allrightsreserved. 1 2 NeuroscienceoftheNonconsciousMind FIGURE1.1 Schematicrepresentationofasimplifiedvedicconceptofconsciousness. chitta operates at a deeper level and it provides a framework for the mind to work. It defines a person’s personality by guiding his or her thoughts and actions. These concepts are not much different from those of the modern western philosophy developed in the 19th century after publication of the book Philosophy of the Unconscious.4 The original German version was published by philosopher Karl Robert Eduard von Hartmann (Fig. 13.1) in 1869 and an English translation appeared in 1884. Hartmann bundled vedic concepts with contemporary German philosophy and proposed three forms of noncon- scious/unconscious mind: absolute unconscious, which is a substance of the universe and is the source of all other unconscious; physiological uncon- scious, which is at work in the origin, development, and evolution of living beings; and psychological unconscious, which lies at the source of our con- scious mental life. This concept was further developed by Austrian neurolo- gist Sigmund Freud (Fig. 1.6). In an article titled “The Unconscious,”5 published in 1915, Freud suggested that the unconscious mind primarily works as a repository of information and has no processing function. He developed psychoanalytical techniques to bring nonconscious information to conscious awareness and used them to treat psychological disturbances. It is now clear that the nonconscious mind is not merely a repository; it performs high-level cognitive processing while keeping it out of our conscious aware- ness. Freud also suggested that the unconscious mind modifies our actions based onrepressed desires,drives, and motivations. Since a discussion of philosophical concepts is out of the scope of this book, these concepts will not be discussed. Here, we focus on scientific evi- dence andconcepts. Evidenceoftheexistenceofnonconsciousmindwasexperimentallydem- onstrated for the first time in 1884 by an American logistician named Charles S. Peirce (Fig. 1.2) at Johns Hopkins University. Peirce was admired as one of the greatest logisticians, philosophers, and mathematicians of the time, but because of his antipathy to the then president of Harvard University Charles Elliot, he could not get a faculty position there. He worked as a lecturer at Johns Hopkins but was dismissed because of an extramarital affair. Peirce died in poverty and lived on donated money raised Historicalperspective Chapter | 1 3 FIGURE1.2 CharlesPeirce(1839(cid:1)1914).Conductedexperimentsonthenonconsciousmind. ReprintedfromWikimediaCommons. FIGURE1.3 BorisSidis(1867(cid:1)1923).Hisexperimentsprovidescientificevidenceoftheexis- tenceofnonconsciousmind.ReproducedfromWikimediaCommons. by his friend William James (Fig. 7.1), a well-known psychologist at Harvard. After death, Peirce left 1650 unpublished manuscripts in over 100,000pages. Peirce conducted a landmark experiment with Joseph Jastrow (1863(cid:1)1944). In this experiment he asked volunteers to make an estimate of the weight placed on a pane of a balance and also to estimate the degree of confidence in their answer. He found that despite having very low confi- dence, estimates were close to the actual weight.6 This observation made himbelieve thatvolunteers“knew” somethingthatthey werenotconsciously awareof.Peirce conductedanotherexperiment inwhichvolunteersestimated the luminosityofa lamp. He found similar results. With these experiments, Peirce and Jastrow introduced the nonconscious mind to experimental psychology, butthe first major contribution inthis area was made by a psychiatrist Boris Sidis (Fig. 1.3). He described most of his work in the book The Psychology of Suggestion, published in 1898.6,7 Sidis was born in Ukraine and immigrated to the United States in 1887 to avoid political persecution. After receiving PhD and MD degrees from Harvard University, he joined the faculty of its psychology department. Sidis named his son William James in honor of his friend and the famous psychologist

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