Curs 14. Sistemul Nervos Central

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Human nervous system

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  • Human nervous system

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  • Brain Fun FactsSIZE OF THE HUMAN BRAIN The average human brain weighs about 3 pounds (1300-1400 g). At birth, the human brain weighs less than a pound (0.78-0.88 pounds or 350-400 g). As a child grows, the number of cell remains relatively stable, but the cells grow in size and the number of connections increases. The human brain reaches its full size at about 6 years of age.

    COMPOSITION OF THE BRAIN The brain consists of gray matter (40%) and white matter (60%) contained within the skull. Brain cells include neurons and glial cells.

    NOURISHMENT OF THE BRAIN Although the brain is only 2% of the body's weight, it uses 20% of the oxygen supply and gets 20% of the blood flow. Blood vessels (arteries, capillaries, and veins) supply the brain with oxygen and nourishment, and take away wastes. If brain cells do not get oxygen for 3 to 5 minutes, they begin to die.

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  • NERVOUS SYSTEMThe Organisation of the Nervous System

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  • *The Organisation of the Nervous SystemThe spinal cord (SC) runs through the neural arches of the vertebrae and in its centre is a canal containing cerebrospinal fluid.The brain is a highly specialised area of the SC. See laterThe brain and spinal cord are surrounded by 3 membranes called the meningesThe meninges secrete cerebrospinal fluid. The fluid supplies oxygen and nutrients and acts as a shock absorberButterfly shaped area of unmyelinated neurones (grey)Myelinated neurones (white)Canal

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  • Lobes may vary from person to Simpson

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  • The Brains 4 Major RegionsCerebrum, the diencephalon, the brainstem, and the cerebellum. The cerebrum is divided into two halves, called the left and right cerebral hemispheres. Each hemisphere is subdivided into five functional areas called lobes. Outer surface of an adult brain exhibits folds called gyri (gyrus) and shallow depressions between those folds called sulci (sulcus). The brain is associated with 12 pairs of cranial nerves.

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  • Dezvoltarea encefaluluiProsencephalon (forebrain)Telencephalon: cerebrumDiencephalon:epithalamusthalamus,hypothalamus Mesencephalon (midbrain)Mesencephalon: cerebral peduncles, colliculi Rhombencephalon (hindbrain) Metencephalon: pons, cerebellum Myelencephalon: medulla oblongata

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  • Organizarea esutului nervosGray matter:motor neuron and interneuron cell bodies, dendrites, axon terminalsunmyelinated axons. White matter:composed primarily of myelinated axons. lies deep to the gray matter of the cortex. Within the masses of white matter:discrete innermost clusters of gray matter called cerebral nuclei (or basal nuclei).are oval, spherical, or sometimes irregularly shaped clusters of neuron cell bodies. During brain development, an outer, superficial region of gray matter forms from migrating peripheral neurons. External sheets of gray matter, called the cortex, cover the surface of most of the adult brain (the cerebrum and the cerebellum).

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  • Support and Protection of the Brain The brain is protected and isolated by multiple structures:bony cranium Meninges:Protective connective tissue membranessurround and partition portions of the brain. Cerebrospinal fluid (CSF)acts as a cushioning fluid. Blood-brain barrier:prevents entry of harmful materials from the bloodstream. Three dense regular connective tissue layers:separate the soft tissue of the brain from the bones of the cranium.Enclose and protect blood vessels that supply the brain.Contain and circulate cerebrospinal fluid.Parts of the cranial meninges form some of the veins that drain blood from the brain. From superficial to deep, the cranial meninges are the dura mater, the arachnoid, and the pia mater

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  • Dura MaterTough membrane composed of two fibrous layers. Strongest of the meninges. Dura mater is composed of two layers.periosteal layer, the more superficial layer, attaches to the periosteum of the cranial bonesmeningeal layer lies deep to the periosteal layer The meningeal layer is usually fused to the periosteal layer Exception: in specific areas where the two layers separate to form large, blood-filled spaces called dural venous sinuses.

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  • Arachnoid Also called the arachnoid mater or the arachnoid membrane. Lies immediately internal to the dura mater.Partially composed of a delicate web of collagen and elastic fibers, termed the arachnoid trabeculae.Between the arachnoid and the overlying dura mater is the subdural space.Immediately deep to the arachnoid is the subarachnoid space.

    The innermost of the cranial meninges. Thin layer of delicate connective tissue that tightly adheres to the brain and follows every contour of the brain surface.

    Pia Mater

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  • Cranial Dural SeptaThe meningeal layer of the dura mater extends as flat partitions (septa) deep into the cranial cavity;at four locationscalled cranial dural septa. Membranous partitions separate specific parts of the brain and provide additional stabilization and support to the entire brain.falx cerebritentorium cerebelli falx cerebellidiaphragma sellae

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  • The Spinal CordThe spinal cord is the major nerve pathway to and from the brain.It is protected by the vertebral column and the meninges.31 pairs of spinal nerves branch out from the spinal cord, connecting the brain to the body.Certain kinds of information, such as reflexes, are processed directly in the spinal cord.A reflex is a quick, automatic response to a stimulus. It allows the body to respond to danger immediately.

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  • Brain Ventricles Cavities or expansions within the brain that are derived from the lumen (opening) of the embryonic neural tube. Continuous with one another as well as with the central canal of the spinal cord. Four ventricles in the brain. two lateral ventricles are in the cerebrum, separated by a thin medial partition called the septum pellucidum within the diencephalon is a smaller ventricle called the third ventricle each lateral ventricle communicates with the third ventricle through an opening called the interventricular foramen The fourth ventricle is located within the pons and cerebellum.

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  • Cerebrospinal FluidA clear, colorless liquid that circulates in the ventricles and subarachnoid space.Bathes the exposed surfaces of the central nervous system and completely surrounds it. Performs several important functions. buoyancy protection environmental stability Formed by the choroid plexus in each ventricle. Produced by secretion of a fluid from the ependymal cells that originate from the blood plasma. Is similar to blood plasma.

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  • Cerebrum Account for 83% of brain massFissures deep grooves separate major regions of the brainTransverse fissure separates cerebrum and cerebellumLongitudinal fissure separates cerebral hemispheresSulci grooves on the surface of the cerebral hemispheres Gyri twisted ridges between sulci Prominent gyri and sulci are similar in all peopleDeeper sulci divide cerebrum into lobesLobes are named for the skull bones overlying themCentral sulcus separates frontal and parietal lobesBordered by two gyriPrecentral gyrus Postcentral gyrusParieto-occipital sulcus Separates the occipital from the parietal lobeLateral sulcus Separates temporal lobe from parietal and frontal lobesInsula deep within the lateral sulcus

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  • Cerebral cortex Composed of gray matterNeuronal cell bodies, dendrites, and short axonsFolds in cortex triples its size Approximately 40% of brains massBrodmann areas 52 structurally distinct areas

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  • Cerebrum: functional areas Home of our conscious mind Enables us to: Be aware of ourselves and our sensationsInitiate and control voluntary movementsCommunicate, remember, and understandThree kinds of functional areasMotor areasSensory areasAssociation areas

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  • Motor areasControls motor functionsPrimary motor cortex (somatic motor area)Located in precentral gyrus (Brodmann area 4)Pyramidal cells large neurons of primary motor cortexCorticospinal tracts descend through brainstem and spinal cordAxons signal motor neurons to control skilled movements Contralateral pyramidal axons cross over to opposite side of the brainSpecific pyramidal cells control specific areas of the bodyFace and hand muscles controlled by many pyramidal cellsMotor homunculus body map of the motor cortex

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  • Sensory cortexCortical areas involved in conscious awareness of sensationLocated in parietal, temporal, and occipital lobesDistinct area for each of the major senses

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  • Sensory Areas Visual AreasPrimary visual cortex Corresponds to Brodmann area 17Located deep within the calcarine sulcusOn the posterior and medial part of the occipital lobeReceives visual information that originates on the retinaFirst of a series of areas that interprets visual inputVisual association areaSurrounds the primary visual areaCoincides with Brodmann areas 18 and 19Continues the processing of visual informationComplex visual processing extends into: Temporal and parietal lobes

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  • Sensory Areas Auditory AreasPrimary auditory cortexFunction conscious awareness of soundLocation superior edge of the temporal lobeCorresponds to Brodmann areas 41 and 42Auditory association areaLies posterior to the primary auditory cortexLocated within Brodmann area 22Permits evaluation of different soundsLies in the center of Wernickes area Involved in recognizing and understanding speech

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  • Sensory Areas Gustatory CortexInvolved in the conscious awareness of taste stimuliCorresponds to Brodmann area 43Located on the roof of the lateral sulcus

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  • Sensory Areas Vestibular CortexLocated in the posterior part of the insulaDeep to the lateral sulcus

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  • Sensory Areas Olfactory CortexLies on the medial aspect of the cerebrumLocated in a region called the piriform lobeOlfactory nerves transmit impulses to the olfactory cortexProvides conscious awareness of smellsPart of the rhinencephalon nose brainIncludes the piriform lobe, olfactory tract, and olfactory bulbConnects the brain to the limbic systemExplains why smells trigger emotionsOrbitofrontal cortex Involved with consciously identifying and recalling specific smells

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  • Association areasMake associations between different types of sensory informationAssociate new sensory input with memories of past experiences New name for association areas higher order processing areas

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  • Association Areas Prefrontal CortexLarge region of the frontal lobe anterior to motor areasPerforms cognitive functionsAll aspects of thinking and perceiving Remembering and recalling information Also related to moodHas close links to the limbic part of the forebrainFunctional neuroimaging techniques Reveal functions of specific parts of the prefrontal cortexAnterior pole of frontal cortex Active in solving the most complex problems The farther rostrally one goes in the CNS, the more complex the neural functionsFunctional areas located on the medial side of the frontal lobeRegions anterior to the corpus callosumInvolved in complex personal and social interactionsRegions superior to the corpus callosumInvolved in mentalization

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  • Association Areas General Interpretation AreaFunction is currently under investigationLocated at the interface of: The visual, auditory, and somatosensory association areasNewer studies show most of this region is involved in the visual processing of spatial relationships

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  • Association Areas Language AreaSurrounds the lateral sulcus in the left cerebral hemisphereFive parts have been identifiedBrocas area speech productionWernickes area speech comprehensionLateral prefrontal cortex conceptual analysis of spoken wordsFive parts have been identified (continued)Most of the lateral and inferior temporal lobeCoordination of auditory and visual aspects of languageParts of the insula Initiation of word articulation Recognition of rhymes and sound sequences

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  • Association Areas InsulaFunctions of its cortex not well understoodSome parts function in language and the sense of balanceOther parts visceral functionConscious perception of: Upset stomachFull bladderSome aspects of the sense of smell

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  • Cerebral White MatterDifferent areas of the cerebral cortex communicate:With each other With the brainstem and spinal cordFibers are usually myelinated and bundled into tractsTypes of tractsCommissures composed of commissural fibersAllows communication between cerebral hemispheresCorpus callosum the largest commissureAssociation fibers - Connect different parts of the same hemisphereProjection fibers run vertically Descend from the cerebral cortex Ascend to the cortex from lower regions

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  • Basal nucleiA group of nuclei deep within the cerebral white matterCaudate nucleus arches over the thalamusLentiform nucleus lens shapedAmygdala sits on top of the caudate nucleusFunctionally belongs with the limbic systemLentiform nucleus - Divided into two partsGlobus pallidusPutamenCooperate with the cerebral cortex in controlling movementsReceive input from many cortical areasEvidence shows that they:Start, stop, and regulate intensity of voluntary movementsIn some way estimate the passage of time

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  • The DiencephalonForms the center core of the forebrainSurrounded by the cerebral hemispheresComposed of three paired structures:Thalamus, hypothalamus, and epithalamusBorder the third ventriclePrimarily composed of gray matter

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  • The ThalamusMakes up 80% of the diencephalonContains approximately a dozen major nucleiSend axons to regions of the cerebral cortexNuclei act as relay stations for incoming sensory messagesAfferent impulses converge on the thalamusSynapse in at least one of its nucleiIs the gateway to the cerebral cortexNuclei organize and amplify or tone down signals

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  • The HypothalamusLies between the optic chiasm and the mammillary bodies Pituitary gland projects inferiorly Contains approximately a dozen nucleiMain visceral control center of the bodyFunctions include the following: Control of the autonomic nervous systemControl of emotional responsesRegulation of body temperatureRegulation of hunger and thirst sensationsControl of behaviorRegulation of sleep-wake cyclesControl of the endocrine systemFormation of memory

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  • The EpithalamusForms part of the roof of the third ventricleConsists of a tiny group of nucleiIncludes the pineal gland (pineal body)Secretes the hormone melatonin Under influence of the hypothalamus

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  • The Brain StemIncludes the midbrain, pons, and medulla oblongataSeveral general functionsProduces automatic behaviors necessary for survivalPassageway for all fiber tracts running between the cerebrum and spinal cordHeavily involved with the innervation of the face and head10 of the 12 pairs of cranial nerves attach to it

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  • The MidbrainLies between the diencephalon and the ponsCentral cavity the cerebral aqueductCerebral peduncles located on the ventral surface of the brainContain pyramidal (corticospinal) tractsSuperior cerebellar peduncles- Connect midbrain to the cerebellumPeriaqueductal gray matter surrounds the cerebral aqueductInvolved in two related functions Fright-and-flight reactionMediates response to visceral painCorpora quadrigemina the largest nuclei, divided intoSuperior colliculi nuclei that act in visual reflexesInferior colliculi nuclei that act in reflexive response to soundImbedded in the white matter of the midbrain, presents two pigmented nucleiSubstantia nigra neuronal cell bodies contain melanin, Functionally linked to the basal nucleiRed nucleus lies deep to the substantia nigra, Largest nucleus of the reticular formation

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  • The PonsLocated between the midbrain and medulla oblongataContains the nuclei of cranial nerves V, VI, and VIITwo general groups of cranial nerve nucleiMotor nucleiSensory nuclei

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  • The Medulla OblongataMost caudal level of the brain stemContinuous with the spinal cordChoroid plexus lies in the roof of the fourth ventriclePyramids of the medulla lie on its ventral surface Decussation of the pyramids crossing over of motor tractsCranial nerves VIIIXII attach to the medullaThe core of the medulla contains:Much of the reticular formationNuclei influence autonomic functionsVisceral centers of the reticular formation include:Cardiac centerVasomotor centerThe medullary respiratory centerCenters for hiccupping, sneezing, swallowing, and coughing

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  • The CerebellumLocated dorsal to the pons and medullaSmoothes and coordinates body movements Helps maintain equilibriumConsists of two cerebellar hemispheresSurface folded into ridges called foliaSeparated by fissuresHemispheres each subdivided into:Anterior lobePosterior lobeComposed of three regionsCortex gray matterInternal white matterDeep cerebellar nuclei deeply situated gray matter Cerebellum must receive information On equilibrium On current movements of limbs, neck, and trunkFrom the cerebral cortex

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  • Cerebellar PedunclesFibers to and from the cerebellum are ipsilateralRun to and from the same side of the body Thick tracts connecting the cerebellum to the brain stemSuperior cerebellar pedunclesMiddle cerebellar pedunclesInferior cerebellar peduncles

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  • Functional Brain SystemsNetworks of neurons functioning togetherThe limbic system spread widely in the forebrain The reticular formation spans the brain stem

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  • The Limbic SystemLocation Medial aspect of cerebral hemispheresAlso within the diencephalon Composed of:Septal nuclei, cingulate gyrus, and hippocampal formationPart of the amygdala The fornix and other tracts link the limbic system togetherThe emotional brainCingulate gyrus Allows us to shift between thoughtsInterprets pain as unpleasantHippocampal formation Hippocampus and the parahippocampal gyrus

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  • The Reticular Formation

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  • The Reticular FormationWidespread connections - Ideal for arousal of the brain as a wholeReticular activating system (RAS) Maintains consciousness and alertnessFunctions in sleep and arousal from sleep

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  • Brain Functions Vision Taste Cognition Emotion Speech Language Hearing Motor Cortex Sensory Cortex Autonomic Functions

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  • VisionThe visual cortex resides in the occipital lobe of the brain.Sensory impulses travel from the eyes via the optic nerve to the visual cortex.Damage to the visual cortex can result in blindness.

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  • TasteThe gustatory complex (green circle) is the part of the sensory cortex (purple area) that is responsible for taste.

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  • CognitionThe prefrontal cortex is involved with intellect, complex learning, and personality.Injuries to the front lobe can cause mental and personality changes.

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  • EmotionEmotions are an extremely complex brain function. The emotional core of the brain is the limbic system. This is where senses and awareness are first processed in the brain.Mood and personality are mediated through the prefrontal cortex. This part of the brain is the center of higher cognitive and emotional functions.Prefrontal cortexLimbic system

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  • SpeechBrocas area is where we formulate speech and the area of the brain that sends motor instructions to the motor cortex.Injury to Brocas area can cause difficulty in speaking. The individual may know what words he or she wishes to speak, but will be unable to do so.Brocas Area

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  • LanguageWernickes area is a specialized portion of the parietal lobe that recognizes and understands written and spoken language.Wernickes area surrounds the auditory association area.Damage to this part of the brain can result in someone hearing speech, but not understanding it.Wernickes AreaAuditory Association Area

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  • HearingThere are two auditory areas of the brain: The primary auditory area (brown circle) is what detects sounds that are transmitted from the ear. It is located in the sensory cortex. The auditory association area (purple circle) is the part of the brain that is used to recognize the sounds as speech, music, or noise.

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  • Motivational systemsHUNGER

    THIRST

    SEXUAL BEHAVIOR

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  • HungerLACK OFFOODREDUCEDAVAILABILITYOF GLUCOSECONTRACTIONS OF EMPTYSTOMACHLOWTRIGLYCERIDELEVELSIN FAT CELLSGLUCOSE RECEPTORSIN HYPOTHALAMUSMECHANO-RECEPTORSIN STOMACHPANCREASHUNGER

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  • ThirstWATERDEFICIENCYOSMORECEPTORSIN SUPRAOPTICAND SUPRA-VENTRICULARNUCLEI OFHYPOTHALAMUSTHIRSTADHSERETIONBY PITUITARYWATERRETENTION BY KIDNEY

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  • Sexual behaviorAnterior hypothalamus receives input from de receptors stimulated by feromonesAndrogens determine release of luteinizing hormones, cyclic or constant

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  • Brain PlasticityThe ability of the brain to change as a result of experience, drugs, or injury.Collateral sprouting: growth of new neuron branchesSubstitution of function: other areas of the brain take over for damaged areasNeurogenesis: generating new neurons

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  • Learning takes place in the brain.However, various parts of the brain function differently and provide localized areas for the retention of diverse types of knowledge.

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  • Human Memory System3 memory processesEncoding getting information into memoryStorage keeping the information in memoryRetrieval getting the information back out

    Expert learners have successful strategies for using the first two processes which makes the last one more probable.Types of MemorySensory Store how information enters Gatekeeper of the mindMuch of this is ignored.Short-term Memory working memoryDecays after 30 secondsCan be renewed through maintenance rehearsalLimited capacity (5-9 items)Can be expanded through chunking (ex.SSN)Long-term Memory What you knowUnlimited capacity, unlimited durationMust be retrieved before used (cues)

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  • Two Basic Memory Processes Declarative memoryFacts and eventsOccurs primarily in brain systems involving the hippocampus Procedural memorySkills or cognitive operations that cannot be represented in declarative sentencesOccurs primarily in the brain systems involving the neostriatum

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  • The brain is divided into two halves or hemispheres identified as right and left.The left hemisphere

    iconsidered analytic in approach A successive processor (left brain) prefers to learn in a step-by-step sequential format, beginning with details leading to a conceptual understanding of a skill.

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  • This part of the brain controls and makes the final decisions concerning information collected throughout the brain.At the same time, the left hemisphere simultaneously inhibits the visual-spatial right brains cognitive and decision making processes.

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  • Conversely and concurrentlyThe right brain

    described as holistic or global. A simultaneous processor ( right brain) prefers to learn beginning with the general concept and then going on to specifics.

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  • a left brain person is VerbalResponds to word meaning3. Sequential 4. Processes information linearly5. Responds to logic6. Plans ahead7. Recall people's names8. Speak with few gestures9. Punctual10. Prefer formal study design11. Prefer bright lights while studying

    For example

    Lets meet a week from today to talk about this.

    If this is true, then it is logical that we

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  • Because left-brain thinkers are logical and practical, they are also Ruled by factsDetail orientedUsers of words and languageFocused on the present and pastPerceive order & patternReality basedStrategy Formulators

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  • a right brain person is 1. Visual2. Responds to tone of voice3. Random4. Processes information in varied order5. Responds to emotion6. Impulsive7. Recall peoples faces8. Gesture while speaking9. Less punctual10. Prefer sound/ music background while studying11. Prefer frequent mobility while studying

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  • Because right-brain thinkers are intuitive and willing to take risks, they are also ImaginativeBig Picture orientedUsers of symbols and imagesFocused on the present and futureSpatially perceptiveFantasy basedPresenters of Possibility

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  • Specific learning skills are associated with right and left brain hemispheric dominance.LEFT BRAIN Reading & LanguageSymbolsLocating details & factsTalking & RecitationFollowing DirectionsListeningAuditory Association

    RIGHT BRAINComputation & PatternsSpatial RelationshipsSinging & MusicArt ExpressionCreativityVisualizationFeelings & Emotions

    brain dominance is concerned with ways of perceiving, processing, and organizing information and experiences.

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  • Adolescent brain developmentUnderdevelopment of the frontal lobe/prefrontal cortex and the limbic system make adolescents more prone to behave emotionally or with gut reactionsAdolescents tend to use an alternative part of the brain the AMYGDALA (emotions) rather than the prefrontal cortex (reasoning) to process informationAmygdala and nucleus acumbens (limbic system within the prefrontal cortex) tend to dominate the prefrontal cortex functions this results in a decrease in reasoned thinking and an increase in impulsivenessBecause of immature brains, adolescents do not handle social pressure, instinctual urges, and other stresses the way adults doA major part of adolescence is learning how to assess risk and consequences adolescents are not yet skilled at these tasks

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  • Hot and cold cognitionThoughts and emotions are intertwined teens need to develop a balance between cognitive and affective systems of the brainCOLD cognition refers to thinking under conditions of low emotions and/or arousalHOT cognition refers to thinking under conditions of strong feelings or arousalDecisions made under conditions of strong affect are difficult to influence by cool rational thought aloneDecision making in teens cannot be fully understood without considering the role of emotions and the interaction between thinking and feelingTeen decisions are unlikely to emerge from a logical evaluation of the risk/benefits of a situation rather decisions are the result of a complex set of competing feelings desire to look cool, fear of being rejected, anxiety about being caught, excitement of risk, etc.

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  • Mental DisordersCreates problems with feeling, thinking and perception.Affects a persons behavior by involuntarily causing bizarre and/or inappropriate behavior.Are primarily brain disorders.Can be short term (acute) or long term (chronic).Can occur at anytime in a persons life.Associated with distress, orWith significant increased risk of suffering death, pain, disability, or an important loss of freedom.Not an expected response to a particular event (e.g., death of a spouse).Current manifestation of a behavioral, psychological, or biological dysfunction.

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  • Categorization of Mental DisordersDeliriumPsihotic disordersDementiaCognitive disordersAffective disordersAnxiety disordersPersonality disordersSubstance abuse/dependence.Impulse control disorders.Adjustment disorders.Sexual disorders

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  • Alcohol & Other Drug AbuseAbuse and Dependence Both Defined as Mental Disorder in DSM IV. Dependence is Pattern of Use Causing Impairment or Distress Including ToleranceWithdrawalIncreasing Amounts Over Longer TimeUnsuccessful Attempts to Control UseTime Spent Obtaining, Using, RecoveringActivities Given Up Due to UseContinued Use Despite Problems

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  • Alcohol & Other Drug Abuse:Long term use can result in deteriorated functioning.Can cause:Depression.Dementia.Anxiety disorders.Use and withdrawal can cause acute psychotic symptoms.Addiction is chronic, progressive, & terminal.

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  • Mental RetardationBelow Average Intellectual Functioning.Begins Before Age 18, Usually Present at Birth.Unrelated to Other MentalIllness.Impaired Social-living Adaptation & Functioning:Personal care & hygiene.Money management.Leisure activities.Social relationships.

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  • The Brain - FunctionShrinkage of brain tissue.Ventricles enlarge. short-term memory begins to decline ability to perform routine tasks also declines. Emotional outbursts may occur and language is impaired. Progressively more nerve cells die with subsequent behaviour changes, such as wandering and agitation.The ability to recognize faces and to communicate is completely lost in the final stages. Patients lose bowel and bladder control, and eventually need constant care.The average length of time from diagnosis to death is 4 to 8 years, but can take 20Alzheimers diseaseFirst recorded by Alzheimer after studying the brain of a woman who had died after suffering dementia in 1906.

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  • *The Brain - FunctionAgeing. Less than 1 in 1000 people < 65 have Alzheimer's. 1 in 20 > 65 has!A small proportion of sufferers have a genetic (familial) formA varied and active life may help avoid Alzheimers.Severe blows to the head (especially in the over 50s) may increase the chance of developing the diseaseSmoking and high cholesterol may also be risk factors for AlzheimersFuture therapy?A vaccine to break down the amyloid plaques? Trials in mice An inhibitor of the membrane enzyme that breaks down APP into A? Risk factorsAlzheimers

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  • ..WISH YOU GOOD LUCK IN MANAGING YOU BRAIN

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