Published on

Today, researchers are demonstrating that movement plays an essential and primary role in the development of the brain. There is compelling evidence of mind-body connections from anatomical imaging technology, cognitive, and developmental sources.

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide


  1. 1. The Human Brain:Anatomy,Functions,and Injury
  2. 2. Main Menu• Brain Anatomy• Brain Functions• Injury Mechanisms
  3. 3. Brain Anatomy MenuSkull Anatomy The Limbic SystemInterior Skull Surface CerebellumBlood Vessels of the Brain ThalamusArteries of the Brain HypothalamusThe Neuron The Medulla OblongataThe Meninges The PonsExternal Brain Structures The VentriclesThe Cerebrum Cerebrospinal FluidThe Cerebrum – The Cortex The BrainstemThe Neocortex Brainstem ComponentsLobes of the Cerebrum Brainstem Divisions Frontal Lobe The Cranial Nerves Temporal Lobe Parietal Lobe Occipital Lobe Limbic Lobe
  4. 4. Skull AnatomyThe skull is a rounded layer ofbone designed to protect the brainfrom penetrating injuries. Blood Vessels of the Skull Rough Interior of Skull
  5. 5. Interior Skull Surface The base of the skull is rough, Bony ridges with many bony protuberances. These ridges can result in injury to the temporal lobe of the brain during rapid acceleration. Injury from contact with skull
  6. 6. Blood Vessels of the Skull The brain requires a rich blood supply, and the space between the skull and cerebrum contains many blood vessels. These blood vessels can be ruptured during trauma, resulting in bleeding. Groove for middle meningeal artery
  7. 7. Arteries of the BrainThe human brain requires aconstant supply of oxygen. Alack of oxygen of just a fewminutes results in irreversibledamage to the brain.
  8. 8. The Neuron Dendrites: Collects information from other neurons. Cell Body Axon: Transmits information to other neurons. Click image to play or pause video
  9. 9. The MeningesThe meninges are layersof tissue that separate theskull and the brain. Skull Dura mater Arachnoid Layer Pia Mater Brain
  10. 10. External Brain Structures
  11. 11. The CerebrumThe largest portion of the brainis the cerebrum. It consists oftwo hemispheres that areconnected together at thecorpus callosum. Corpus callosumThe cerebrum is often dividedinto five lobes that areresponsible for different brainfunctions.
  12. 12. The Cerebrum Neocortex The cerebrum’s surface—the neocortex—is convoluted into hundreds of folds. The neocortex is where all the higher brain functions take place.
  13. 13. The NeocortexThe cerebral cortex is a thin layer of cells about 1.5 to4 mm thick.The cortex provides the connections and pathwaysfor the highest cognitive functions, such as languageand abstract thinking.The cerebral cortex contains about 25 billion neurons,more than 62,000 miles of axons, and300,000,000,000,000 synapses. Neocortex layer The thin layer of the neocortex is dense with neurons.
  14. 14. Lobes of the Cerebrum Limbic LobeFrontal Lobe Parietal Lobe Occipital LobeTemporal Lobe
  15. 15. Frontal LobeThe frontal lobe is the area ofthe brain responsible forhigher cognitive functions.These include:• Problem solving• Spontaneity• Memory• Language• Motivation• Judgment• Impulse control• Social and sexual behavior.
  16. 16. Temporal LobeThe temporal lobe plays arole in emotions, and isalso responsible forsmelling, tasting,perception, memory,understanding music,aggressiveness, andsexual behavior.The temporal lobe alsocontains the languagearea of the brain.
  17. 17. Parietal LobeThe parietal lobe plays arole in our sensations oftouch, smell, and taste. Italso processes sensoryand spatial awareness,and is a key componentin eye-hand co-ordinationand arm movement.The parietal lobe alsocontains a specializedarea called Wernicke’sarea that is responsiblefor matching writtenwords with the sound ofspoken speech.
  18. 18. Occipital LobeThe occipital lobe is atthe rear of the brainand controls visionand recognition.
  19. 19. Limbic LobeThe limbic lobe islocated deep in thebrain, and makes upthe limbic system.
  20. 20. The Limbic SystemThe limbic system is thearea of the brain thatregulates emotion andmemory. It directlyconnects the lower andhigher brain functions.A. Cingulate gyrusB. FornixC. Anterior thalamic nucleiD. HypothalamusE. Amygdaloid nucleusF. Hippocampus
  21. 21. CerebellumThe cerebellum is connected to thebrainstem, and is the center forbody movement and balance.
  22. 22. ThalamusThalamus means ―inner room‖ in Greek,as it sits deep in the brain at the top ofthe brainstem.The thalamus is called the gateway tothe cerebral cortex, as nearly allsensory inputs pass through it to thehigher levels of the brain.
  23. 23. HypothalamusThe hypothalamus sits under the thalamus atthe top of the brainstem. Although thehypothalamus is small, it controls many criticalbodily functions:• Controls autonomic nervous system• Center for emotional response and behavior• Regulates body temperature• Regulates food intake• Regulates water balance and thirst The hypothalamus is• Controls sleep-wake cycles shaded blue. The pituitary• Controls endocrine system gland extends from the hypothalamus.
  24. 24. The Medulla OblongataThe medulla oblongata mergesseamlessly with the spinal cord andcreates the base of the brainstem.The medulla is primarily a controlcenter for vital involuntary reflexessuch as swallowing, vomiting,sneezing, coughing, and regulation ofcardiovascular and respiratory activity.The medulla is also the origin of manycranial nerves.
  25. 25. The PonsThe pons is the roundedbrainstem region between themidbrain and the medullaoblongata. In fact, pons means―bridge‖ in Latin.The main function of the pons isto connect the cerebellum to therest of the brain and to modify therespiratory output of the medulla.The pons is the origin of severalcranial nerves.
  26. 26. The VentriclesThe ventricles are a complexseries of spaces and tunnelsthrough the center of the brain.The ventricles secretecerebrospinal fluid, whichsuspends the brain in the skull.The ventricles also provide aroute for chemical messengersthat are widely distributed throughthe central nervous system.
  27. 27. Cerebrospinal FluidCerebrospinal fluid is a colorlessliquid that bathes the brain and spine.It is formed within the ventricles of thebrain, and it circulates throughout thecentral nervous system.Cerebrospinal fluid fills the ventriclesand meninges, allowing the brain to―float‖ within the skull.
  28. 28. The BrainstemThe brainstem is the mostprimitive part of the brain andcontrols the basic functions oflife: breathing, heartrate, swallowing, reflexes tosight or sound, sweating, bloodpressure, sleep, and balance.The brainstem can be dividedinto three major sections.Detailed brainstem anatomy.
  29. 29. Brainstem Components FrontMore Information: RearMedullaThalamusPons
  30. 30. Brainstem Divisions Midbrain Pons Medulla Oblongata
  31. 31. The Cranial NervesI. Olfactory nerveII. Optic nerveIII. Oculomotor nerveIV. Trochlear nerveV. Trigeminal nerveVI. Abducens nerveVII. Facial nerveVIII. Vestibulocochlear nerveIX. Glossopharyngeal nerveX. Vagus nerveXI. Accessory nerveXII. Hypoglossal nerve
  32. 32. Injury MechanismsThe brain is a complex and delicate organ, and onethat is vulnerable to injury from a variety of differenttraumas. These include: Frontal Lobe Injury Occipital Lobe Injury Temporal Lobe Injury Side Impact Injury Coup/Contre-coup Injury Diffuse Axonal Injury Epidural Hematoma Subdural Hematoma
  33. 33. Frontal Lobe InjuryThe frontal lobe of the brain can beinjured from direct impact on thefront of the head.During impact, the brain tissue isaccelerated forward into the bonyskull. This can cause bruising ofthe brain tissue and tearing ofblood vessels.Frontal lobe injuries can causechanges in personality, as well asmany different kinds ofdisturbances in cognition andmemory.
  34. 34. Occipital Lobe InjuryOccipital lobe injuriesoccur from blows to theback of the head.This can cause bruisingof the brain tissue andtearing of blood vessels.These injuries can resultin vision problems oreven blindness.
  35. 35. Temporal Lobe InjuryThe temporal lobe of the brain isvulnerable to injury from impactsof the front of the head.The temporal lobe lies upon thebony ridges of the inside of theskull, and rapid acceleration cancause the brain tissue to smashinto the bone, causing tissuedamage or bleeding.
  36. 36. Side Impact InjuryInjuries to the right or left sideof the brain can occur frominjuries to the side of the head.Injuries to this part of the braincan result in language orspeech difficulties, andsensory or motor problems.
  37. 37. Coup/Contre-coup InjuryA French phrase that describesbruises that occur at two sitesin the brain.When the head is struck, theimpact causes the brain tobump the opposite side of theskull. Damage occurs at thearea of impact and on theopposite side of the brain.
  38. 38. Diffuse Axonal InjuryBrain injury does not require adirect head impact. Duringrapid acceleration of the head,some parts of the brain canmove separately from otherparts. This type of motioncreates shear forces that candestroy axons necessary forbrain functioning.These shear forces can stretchthe nerve bundles of the brain.More on diffuse axonal injury.
  39. 39. Diffuse Axonal InjuryThe brain is a complexnetwork of interconnections.Critical nerve tracts can besheared and stressed duringan acceleration-type of injury. Diffuse axonal injury is a very serious injury, as it directly impacts the major pathways of the brain.
  40. 40. Epidural HematomaAn epidural hematoma is ablood clot that forms betweenthe skull and the top lining ofthe brain (dura).This blood clot can cause fastchanges in the pressure insidethe brain.When the brain tissue iscompressed, it can quicklyresult in compromised bloodflow and neuron damage.
  41. 41. Subdural HematomaA subdural hematoma is ablood clot that forms betweenthe dura and the brain tissue.The clot may cause increasedpressure and may need to beremoved surgically.When the brain tissue iscompressed, it can quicklyresult in compromised bloodflow and tissue damage.
  42. 42. Brain Functions• Vision• Taste• Cognition• Emotion• Speech• Language• Hearing• Motor Cortex• Sensory Cortex• Autonomic Functions
  43. 43. VisionThe visual cortex resides in theoccipital lobe of the brain.Sensory impulses travel fromthe eyes via the optic nerve tothe visual cortex.Damage to the visual cortexcan result in blindness.
  44. 44. TasteThe gustatory complex(green circle) is the partof the sensory cortex(purple area) that isresponsible for taste.
  45. 45. CognitionThe prefrontal cortex isinvolved with intellect,complex learning, andpersonality.Injuries to the front lobecan cause mental andpersonality changes.
  46. 46. Emotion Prefrontal cortexEmotions are an extremelycomplex brain function. Theemotional core of the brain is thelimbic system. This is wheresenses and awareness are firstprocessed in the brain.Mood and personality aremediated through the prefrontalcortex. This part of the brain isthe center of higher cognitive andemotional functions. Limbic system
  47. 47. Speech Broca’s AreaBroca’s area is where weformulate speech and thearea of the brain that sendsmotor instructions to themotor cortex.Injury to Broca’s area cancause difficulty in speaking.The individual may knowwhat words he or she wishesto speak, but will be unableto do so.
  48. 48. Language Auditory Association AreaWernicke’s area is aspecialized portion of theparietal lobe that recognizesand understands written andspoken language.Wernicke’s area surrounds theauditory association area.Damage to this part of thebrain can result in someonehearing speech, but notunderstanding it. Wernicke’s Area
  49. 49. HearingThere are two auditoryareas of the brain:• The primary auditoryarea (brown circle) is whatdetects sounds that aretransmitted from the ear. Itis located in the sensorycortex.• The auditory associationarea (purple circle) is thepart of the brain that isused to recognize thesounds as speech, music,or noise.
  50. 50. Motor CortexThe motor portion of thecerebrum is illustrated here. Thelight red area is the premotorcortex, which is responsible forrepetitive motions of learnedmotor skills. The dark red area isthe primary motor area, and isresponsible for control ofskeletal muscles.Different areas of the brain areassociated with different parts ofthe body.Injury to the motor cortex canresult in motor disturbance in theassociated body part.
  51. 51. Sensory CortexThe sensory portion of thecerebrum is illustrated here.Different areas of the brain areassociated with different parts ofthe body, as can be seen below.Injury to the sensory cortex canresult in sensory disturbance inthe associated body part.
  52. 52. Autonomic FunctionsThe brainstem controls the basicfunctions of life. Damage to theseareas of the brain are usuallyfatal:•The pons plays a critical role inrespiration.•The medulla oblongata isresponsible for respiration andcardiovascular functions. Pons Medulla Oblongata
  53. 53. BibliographyThe following are excellent resources and were the basis of the anatomical andfunctional components of this presentation:• The Human Brain: An Introduction to Its Functional Anatomy, Fifth Edition. JohnNolte, Mosby, 2002. ISBN: 0-323-01320-1 Purchase Here• Coping with Mild Traumatic Brain Injury. Dr. Diane Stoler, Avery Penguin Putnam,1998. ISBN: 0895297914 Purchase Here• Human Anatomy and Physiology, Fifth Edition. Elaine N. Marieb,Benjamin/Cummings, 2000. ISBN: 0805349898. Purchase Here