Brain Arousal and Information Theory: Neural and Genetic Mechanisms

216 Pages·2005·2.63 MB·English

by  Donald Pfaff

Brain Arousal and Information Theory

Brain Arousal and
Information Theory
Neural and Genetic Mechanisms
Donald Pfaff
Harvard University Press
Cambridge,MassachusettsandLondon,England
2006
Copyright©2006bythePresidentandFellowsofHarvardCollege
Allrightsreserved.
PrintedintheUnitedStatesofAmerica
LibraryofCongressCataloging-in-PublicationData
Pfaff,DonaldW.,1939–
Brainarousalandinformationtheory:neuralandgeneticmechanisms/
DonaldPfaff.
p.;cm.
Includesbibliographicalreferencesandindex.
ISBN0-674-01920-2(cloth:alk.paper)
1.Arousal(Physiology) 2.Informationtheory. 3.Neurogenetics.
4.Neurophysiology. I.Title.
[DNLM:1.Arousal—physiology. 2.NerveNet—physiology. 3.Neurobiology.
WL103P523b2006]
QP405.P432006
153—dc22 2005046338
Contents
PrefaceandDedication vii
1 TowardaUniversalTheoryofBrainArousal 1
WhatIstoBeExplained?EthologyandtheMechanismsofArousal 2
OperationalDefinitionofArousal 4
AQuantitativeApproachtoPhysicalMeasurementofGeneralizedArousal 6
TheNeurobiologyofArousalConstitutesanInterestingApplicationof
InformationTheory 13
ClaimsforThisChapterandIntroductiontoChaptersFollowing 24
2 AnatomyIsNotDestiny,butaLittleNeuroanatomyHelps 26
MultiplicityandRedundancyofAscendingArousalPathwaysPreventFailure 26
Primitive“MasterCells”intheBrainstemProvideaNeuroanatomic
CorethatTheoreticallyMatchestheBehavioralData 42
Long-DistanceLinesTuningLocalModules 48
SummaryandHypotheticalImplicationsforHumanBehavior 51
3 ArousalIsSignaledbyElectricalDischargesinaSystemofNerveCells 55
TravelingUptheBrainstem 56
SpecialCases:OlfactionandVision 65
InformationalContentGovernsAmplitudeofResponseinNeurons
RelatedtoArousal 66
CerebralCortex,theEEG 68
ElectricalActivityinThreeArousal-RelatedBiologicalSystems 68
4 AutonomicNervousSystemChangesSupportingArousal;
theUnityoftheBody 71
PatternsofAutonomicResponses 72
Reformulations 77
AHighInformationSystemShowsCoordinationsansCorrelation 78
SupportingHormone-DependentBehaviors 81
Summary 82
5 GenesWhoseNeurochemicalProductsSupportArousal 83
GenesAssociatedwithClassicalSystems 83
GenesNewlyRecognized 90
ConceptsandQuestions 95
Summary 98
6 HeightenedStatesofArousal:SexComparedtoFear 99
SexBehavior’sCNSMechanismsRequireArousal 100
GeneralizedArousalAffectsSpecificArousalsandViceVersa 107
ContrastSexandFear 115
ApplicabilityofInformationTheory 119
LibidoandStressinHumans 120
Summary 124
7 MajorSystemsQuestionsaboutBrainArousalNetworks 125
WhatAreUniversalOperatingFeaturesofArousalSystems? 126
HowDoWeMeettheRequirementforRapidChangesofCNSState? 129
SensitivityandAlacrityofResponse,YetStability?How? 131
DoesAutomataTheoryApply? 132
QuestionsintheTimeDomain 136
QuestionsaboutSpatialProperties 137
Thermodynamics,InformationTheory,andQuestionsfortheCNS 138
HowDoesaSineWaveImpactaSawtooth? 140
UnityfromDiversity? 141
8 SummaryandPracticalImportance:FromBiologicalMechanismsto
HealthApplications 143
MainPoints 143
ApplicationstoHumanConditions 147
WorksCited 155
Acknowledgments 197
Index 199
vi Contents
Preface and Dedication
ThisbookisdedicatedtoFredPlum,M.D.,UniversityProfessorEmeritusof
Neurology and former Chair of Neurology at Cornell University School of
Medicine.Heroicallyhedevotedhiseffortstotheunderstandingandamelio-
rationofdisordersofhumanCNSarousal.Hewasgeneroustomeinarrang-
ing Wednesday lunches with brilliant younger members of his department,
Nicholas Schiff, M.D. (Director, Laboratory of Cognitive Neuromodula-
tionandAssistantProfessorofNeurologyandNeuroscience),KeithPurpura,
Ph.D. (Associate Professor of Neuroscience), Jonathan Victor, M.D., Ph.D.
(Professor of Neurology), and with his colleague then at Cornell, Michael
Posner,Ph.D.Talkingwiththem,IrealizedthatIcouldexpandmyownlab’s
workfromexplainingthemechanismsofsimpleinstinctivebehaviorsandspe-
cific forms of motivation to more general arousal states. But I had not read
aboutthelattersincecross-registeringfromM.I.T.toHarvardMedicalSchool
morethan30yearsbefore.The“pilgrimages”frommyRockefellerlabacross
the street to Fred Plum’s conference room supplied much of the background
andcourageneededtoattemptthisbook.
IalsowishtothankParParekh,ofTheRockefellerUniversity,forhisex-
pert management of the illustrations and tables and extensive textual criti-
cisms.
Thebookisintendedtoproposenewideasformycolleaguesinthisfield,
butnottosubstituteforanAnnualReviewsarticleinitsscientificdetail.There-
fore, it is heavily referenced to the original literature and to pertinent review
papersforproperscholarlysupport.Ihavetriedtowriteitinanopenandclear
fashion, so that readers with college educations in science could understand
the main ideas, and appreciate my excitement as a neurobiologist working in
thisfieldatthistime.

Brain Arousal and Information Theory