alterations in cognitive systems, cerebral hemodynamics, and motor function chapter 16 mosby items...

Alterations in Cognitive Systems, Alterations in Cognitive Systems, Cerebral Hemodynamics, and Motor Cerebral Hemodynamics, and Motor

Function Function

Chapter 16Chapter 16

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.

2Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.

Alterations in Cognitive SystemsAlterations in Cognitive Systems ConsciousnessConsciousness

Arousal vs. awareness Arousal vs. awareness • State of wakefulnessState of wakefulness

• Mediated by the reticular activating systemMediated by the reticular activating system

AwarenessAwareness• Cognitive functions that embody awareness of self, Cognitive functions that embody awareness of self,

environment, and affective states (i.e., moods) environment, and affective states (i.e., moods)

• Content of thoughtContent of thought


Alterations in ArousalAlterations in Arousal Coma is produced by either:Coma is produced by either:

Bilateral hemisphere damage or suppressionBilateral hemisphere damage or suppression Brainstem lesions or metabolic derangement that Brainstem lesions or metabolic derangement that

damages or suppresses the reticular activating damages or suppresses the reticular activating systemsystem


Alterations in ArousalAlterations in Arousal StructuralStructural

SupratentorialSupratentorial InfratentorialInfratentorial SubduralSubdural ExtracerebralExtracerebral Intracerebral Intracerebral

MetabolicMetabolic Psychogenic Psychogenic


Alterations in ArousalAlterations in Arousal Clinical manifestationsClinical manifestations

Level of consciousness changesLevel of consciousness changes Pattern of breathingPattern of breathing

• Posthyperventilation apnea (PHVA)Posthyperventilation apnea (PHVA)

• Cheyne-Stokes respirations (CSR)Cheyne-Stokes respirations (CSR)

Pupillary changesPupillary changes Oculomotor responses (Doll’s eyes)Oculomotor responses (Doll’s eyes) Motor responsesMotor responses


Clinical ManifestationsClinical Manifestations


Brain Death (Brainstem Death)Brain Death (Brainstem Death)

Body cannot maintain internal homeostasisBody cannot maintain internal homeostasis Brain death criteriaBrain death criteria

Completion of all appropriate, therapeutic proceduresCompletion of all appropriate, therapeutic procedures Unresponsive coma (absence of motor and reflex Unresponsive coma (absence of motor and reflex

responses)responses) No spontaneous respirations (apnea)No spontaneous respirations (apnea) No cephalic (ocular or caloric) reflexesNo cephalic (ocular or caloric) reflexes Isoelectric EEGIsoelectric EEG Persistence for 1 hour and 6 hours after onsetPersistence for 1 hour and 6 hours after onset


Cerebral DeathCerebral Death Cerebral death (irreversible coma): death of Cerebral death (irreversible coma): death of

the cerebral hemispheres exclusive of the the cerebral hemispheres exclusive of the brainstem and cerebellum brainstem and cerebellum

No behavioral or environmental responsesNo behavioral or environmental responses The brain can continue to maintain normal The brain can continue to maintain normal

respiratory and cardiovascular functions, respiratory and cardiovascular functions, temperature control, and GI functiontemperature control, and GI function


Cerebral DeathCerebral Death Survivors of cerebral deathSurvivors of cerebral death

Remain in comaRemain in coma Emerge into a vegetative state (“wakeful Emerge into a vegetative state (“wakeful

unconscious state”) unconscious state”) Progress into a minimal conscious stateProgress into a minimal conscious state

• Akinetic mutism (AM)Akinetic mutism (AM)

• Locked-in syndromeLocked-in syndrome


SeizuresSeizures Disruption in balance of excitation and Disruption in balance of excitation and

inhibition inhibition Sudden, transient alteration of brain function Sudden, transient alteration of brain function

caused by an abrupt caused by an abrupt explosive, disorderlyexplosive, disorderly discharge of cerebral neuronsdischarge of cerebral neurons

Motor, sensory, autonomic, or psychicMotor, sensory, autonomic, or psychic ConvulsionConvulsion

Tonic-clonic (jerky, contract-relax) movements Tonic-clonic (jerky, contract-relax) movements associated with some seizuresassociated with some seizures


SeizuresSeizures Generalized seizuresGeneralized seizures Partial (focal) seizuresPartial (focal) seizures Secondary generalizationSecondary generalization Status epilepticusStatus epilepticus

Experience of a second seizure before the person Experience of a second seizure before the person has fully regained consciousness from the has fully regained consciousness from the preceding seizure or a single seizure lasting more preceding seizure or a single seizure lasting more than 30 minutesthan 30 minutes


SeizuresSeizures Resting potential instabilityResting potential instability Bursts of action potentials Bursts of action potentials

(hypersynchronization)(hypersynchronization) Epileptogenic focusEpileptogenic focus

Group of neurons that appear to be hypersensitive Group of neurons that appear to be hypersensitive to paroxysmal depolarizationto paroxysmal depolarization

Tonic phaseTonic phase Clonic phaseClonic phase Postictal statePostictal state

State that follows the seizureState that follows the seizure


Seizures: ConsequencesSeizures: Consequences 250% increase in adenosine triphosphate (ATP)250% increase in adenosine triphosphate (ATP) Cerebral oxygen consumption increased by 60%Cerebral oxygen consumption increased by 60% Cerebral blood flow also increases approximately Cerebral blood flow also increases approximately

250%250% Available glucose and oxygen are depleted Available glucose and oxygen are depleted

With severe seizures the brain tissue may require more With severe seizures the brain tissue may require more ATP than can be produced ATP than can be produced

Lactate accumulates in the brain tissuesLactate accumulates in the brain tissues May produce secondary hypoxia, acidosis, and lactate May produce secondary hypoxia, acidosis, and lactate

accumulationaccumulation May result in progressive brain tissue injury and May result in progressive brain tissue injury and

destruction destruction Cellular exhaustion and destructionCellular exhaustion and destruction


Seizure SyndromesSeizure Syndromes EpilepsyEpilepsy

““To be seized by a force from without”To be seized by a force from without” TypesTypes

• IdiopathicIdiopathic

• Symptomatic Symptomatic

• CryptogenicCryptogenic

AuraAura ProdromaProdroma


Alterations in AwarenessAlterations in Awareness Selective attentionSelective attention

Ability to select from available competing Ability to select from available competing environmental and internal stimulienvironmental and internal stimuli

Sensory inattentivenessSensory inattentiveness• ExtinctionExtinction

• Neglect syndromeNeglect syndrome

Selective attention deficitSelective attention deficit


Alterations in AwarenessAlterations in Awareness Declarative memoryDeclarative memory Nondeclarative memoryNondeclarative memory DysmnesiaDysmnesia

Retrograde amnesiaRetrograde amnesia Anterograde amnesiaAnterograde amnesia

Vigilance, detection, and working memory Vigilance, detection, and working memory deficitsdeficits


Data Processing DeficitsData Processing Deficits AgnosiaAgnosia

Tactile, visual, auditory, etc. Tactile, visual, auditory, etc. AphasiaAphasia DysphasiaDysphasia

Expressive dysphasiaExpressive dysphasia Transcortical dysphasiaTranscortical dysphasia


Acute Confusional StatesAcute Confusional States

Acquired mental disorder with deficits in attention Acquired mental disorder with deficits in attention and coherence of thoughts and actionand coherence of thoughts and action Secondary to drug intoxication, metabolic disorder, or Secondary to drug intoxication, metabolic disorder, or

nervous system diseasenervous system disease Disruption of reticular activating system of upper Disruption of reticular activating system of upper

brainstem and its projections to thalamus, basal brainstem and its projections to thalamus, basal ganglion, and specific areas of the cortex and limbic ganglion, and specific areas of the cortex and limbic areas areas

Abrupt onsetAbrupt onset


DementiaDementia Progressive failure of cerebral functions not Progressive failure of cerebral functions not

caused by an impaired level of caused by an impaired level of consciousnessconsciousness

ClassificationsClassifications CorticalCortical

• Alzheimer and Pick diseasesAlzheimer and Pick diseases

SubcorticalSubcortical• Parkinson and Huntington diseasesParkinson and Huntington diseases

Cortical and subcorticalCortical and subcortical• Infectious and Creutzfeldt-Jakob diseasesInfectious and Creutzfeldt-Jakob diseases


Alzheimer DiseaseAlzheimer Disease Familial, early and late onsetFamilial, early and late onset Nonhereditary (sporadic, late onset)Nonhereditary (sporadic, late onset) TheoriesTheories

Mutation for encoding amyloid precursor proteinMutation for encoding amyloid precursor protein Alteration in apolipoprotein EAlteration in apolipoprotein E Pathologic activation of Pathologic activation of NN-methyl--methyl-DD-aspartate -aspartate

(NMDA)(NMDA)


Alzheimer DiseaseAlzheimer Disease

Neurofibrillary tanglesNeurofibrillary tangles Senile plaquesSenile plaques Clinical manifestationsClinical manifestations

Forgetfulness, emotional upset, disorientation, Forgetfulness, emotional upset, disorientation, confusion, lack of concentration, decline in abstraction, confusion, lack of concentration, decline in abstraction, problem solving, and judgmentproblem solving, and judgment

Insidious onsetInsidious onset Diagnosis made by ruling out other causes of Diagnosis made by ruling out other causes of

dementiadementia


Increased Intracranial PressureIncreased Intracranial Pressure Normal 5 to 15 mmHgNormal 5 to 15 mmHg Caused by increased intracranial contentCaused by increased intracranial content

Tumor growth, edema, excessive CSF, or Tumor growth, edema, excessive CSF, or hemorrhagehemorrhage

Stage oneStage one Stage twoStage two Stage threeStage three Stage fourStage four


HerniationHerniation


Herniation SyndromesHerniation Syndromes Supratentorial herniationSupratentorial herniation

UncalUncal• Uncus or hippocampal gyrus (or both) shifts from the Uncus or hippocampal gyrus (or both) shifts from the

middle fossa through the tentorial notch into the middle fossa through the tentorial notch into the posterior fossaposterior fossa

CentralCentral• Downward shift of the diencephalon through the Downward shift of the diencephalon through the

tentorial notchtentorial notch CingulateCingulate

• Cingulate gyrus shifts under the falx cerebriCingulate gyrus shifts under the falx cerebri Infratentorial herniationInfratentorial herniation


Cerebral EdemaCerebral Edema Increase in the fluid (intracellular or Increase in the fluid (intracellular or

extracellular) within the brainextracellular) within the brain TypesTypes

VasogenicVasogenic CytotoxicCytotoxic IschemicIschemic InterstitialInterstitial


HydrocephalusHydrocephalus Variety of conditionsVariety of conditions Excess fluid within the cranial vault, Excess fluid within the cranial vault,

subarachnoid space, or bothsubarachnoid space, or both Caused by interference in CSF flowCaused by interference in CSF flow

Decreased reabsorptionDecreased reabsorption Increased fluid productionIncreased fluid production Obstruction within the ventricular systemObstruction within the ventricular system


HydrocephalusHydrocephalus Noncommunicating hydrocephalusNoncommunicating hydrocephalus Communicating (extraventricular) Communicating (extraventricular)

hydrocephalushydrocephalus Hydrocephalus ex vacuoHydrocephalus ex vacuo Normal-pressure hydrocephalusNormal-pressure hydrocephalus


Alterations in Motor FunctionAlterations in Motor Function HypotoniaHypotonia HypertoniaHypertonia SpasticitySpasticity Gegenhalten (paratonia)Gegenhalten (paratonia) RigidityRigidity


Alterations in MovementAlterations in Movement Paresis and paralysisParesis and paralysis

Pyramidal motor syndromesPyramidal motor syndromes Upper motor neuron syndromesUpper motor neuron syndromes

• Hemiparesis or hemiplegiaHemiparesis or hemiplegia

• DiplegiaDiplegia

• Paraparesis or paraplegiaParaparesis or paraplegia

• Quadriparesis or quadriplegiaQuadriparesis or quadriplegia

• Spinal shockSpinal shock


Alterations in MovementAlterations in Movement


Alterations in MovementAlterations in Movement Lower motor neuron syndromesLower motor neuron syndromes

Flaccid paresis or flaccid paralysisFlaccid paresis or flaccid paralysis Hyporeflexia or areflexiaHyporeflexia or areflexia Gamma neuropathiesGamma neuropathies FibrillationFibrillation


Lower Motor Neuron SyndromesLower Motor Neuron Syndromes


Lower Motor Neuron SyndromesLower Motor Neuron Syndromes AmyotrophiesAmyotrophies

Paralytic poliomyelitisParalytic poliomyelitis Nuclear palsiesNuclear palsies Progressive spinal muscular atrophyProgressive spinal muscular atrophy Progressive bulbar palsyProgressive bulbar palsy Bulbar palsyBulbar palsy


Alterations in MovementAlterations in Movement HyperkinesiaHyperkinesia

Excessive movementExcessive movement Chorea, wandering, tremor at rest, postural Chorea, wandering, tremor at rest, postural

tremor, etc.tremor, etc. Paroxysmal dyskinesiasParoxysmal dyskinesias Tardive dyskinesiaTardive dyskinesia


Alterations in MovementAlterations in Movement Huntington diseaseHuntington disease

Also known as choreaAlso known as chorea Autosomal dominant hereditary-degenerative disorderAutosomal dominant hereditary-degenerative disorder Severe degeneration of the basal ganglia (caudate Severe degeneration of the basal ganglia (caudate

and putamen nuclei) and frontal cerebral cortexand putamen nuclei) and frontal cerebral cortex• Depletion of gamma-aminobutyric acid (GABA)Depletion of gamma-aminobutyric acid (GABA)

Choreiform movemetsChoreiform movemets Disrupted thought processesDisrupted thought processes


Alterations in MovementAlterations in Movement HypokinesiaHypokinesia

Decreased movementDecreased movement AkinesiaAkinesia BradykinesiaBradykinesia Loss of associated movementLoss of associated movement


Parkinson DiseaseParkinson Disease Severe degeneration of the basal ganglia Severe degeneration of the basal ganglia

(corpus striatum) involving the dopaminergic (corpus striatum) involving the dopaminergic nigrostriatal pathwaynigrostriatal pathway Parkinsonian rigidityParkinsonian rigidity Parkinsonian bradykinesiaParkinsonian bradykinesia Parkinsonian tremorParkinsonian tremor Postural abnormalitiesPostural abnormalities Autonomic and neuroendocrine symptomsAutonomic and neuroendocrine symptoms Cognitive-affective symptomsCognitive-affective symptoms


Parkinson and DementiaParkinson and Dementia 50% of persons have depression, an inherent part of the 50% of persons have depression, an inherent part of the

pathologic state and not a situational responsepathologic state and not a situational response 30% treated on outpatient basis have dementia; 80% of 30% treated on outpatient basis have dementia; 80% of

persons requiring institutional care have dementiapersons requiring institutional care have dementia Disorientation, confusion, memory loss, distractibility, and Disorientation, confusion, memory loss, distractibility, and

difficulty with concept formation, abstraction, calculations, difficulty with concept formation, abstraction, calculations, thinking, and judgmentthinking, and judgment

Symptoms fluctuate, but they progressively worsenSymptoms fluctuate, but they progressively worsen Anxiety disorders; impulse-control disorders; and punding, a Anxiety disorders; impulse-control disorders; and punding, a

disorder of stereotypic motor behavior in which there is disorder of stereotypic motor behavior in which there is intense fascination with repetitive handling and examining of intense fascination with repetitive handling and examining of mechanical objectsmechanical objects

Excessive daytime sleepiness is experienced in more than Excessive daytime sleepiness is experienced in more than 50% of persons 50% of persons


Disorders of Posture (Stance)Disorders of Posture (Stance) DystoniaDystonia

Dystonic postures and movementsDystonic postures and movements Decorticate postureDecorticate posture Decerebrate postureDecerebrate posture Basal ganglion postureBasal ganglion posture Senile postureSenile posture


Disorders of Posture (Stance)Disorders of Posture (Stance)


Disorders of GaitDisorders of Gait Spastic gaitSpastic gait Scissors gaitScissors gait Cerebellar gaitCerebellar gait Basal ganglion gaitBasal ganglion gait Senile gaitSenile gait


Disorders of ExpressionDisorders of Expression HypermimesisHypermimesis HypomimesisHypomimesis Dyspraxias and apraxiasDyspraxias and apraxias


Disorders of ExpressionDisorders of Expression


Extrapyramidal Motor SyndromesExtrapyramidal Motor Syndromes Basal ganglia motor syndromesBasal ganglia motor syndromes Cerebellar motor syndromesCerebellar motor syndromes

Rostral vermisRostral vermis Caudal vermisCaudal vermis Neocerebellar syndromeNeocerebellar syndrome

alterations in cognitive systems, cerebral hemodynamics, and motor function chapter 16 mosby items...

Documents