5. CNS Outer Coverings Inner Coverings Brain Spinal Cord Meninges
cranial bones
Spinal Cord
vertebrate
Inner Coverings
Meninges
Dura mater
Arachnoid membrane
Pia mater

6. Subarachnoid Space (contains CSF)
Epidural Space
Subdural Space
Subarachnoid Space
Dura Mater
Arachnoid Membrane
Pia Mater
Arachnoid
Pia
Dura sc
vertebrate
Epidural Space
Subdural Space
Subarachnoid Space (contains CSF)

7. Meninges Dura Mater Outer layer Strong, white fibrous tissue
Falx cerebri – extension of dura mater that extends vertically to separate two hemispheres
Arachnoid Membrane
Middle layer
Delicate, cobwebby
Pia Mater
Inner layer (adheres to outer surface of brain and spinal cord)
Transparent
Contains blood vessels

8. Meninges Spaces Epidural Space
Between dura mater and bony covering of brain and spinal cord
Supportive cushion of fat
Subdural Space
Between dura mater and arachnoid membrane
Lubricating serous fluid
Subarachnoid Space
Between arachnoid and pia mater
Contains cerebrospinal fluid (CSF)

11. Meningitis infection/swelling of meninges
caused by infection with viruses, bacteria, or other microorganisms
may also arise due to certain drugs or other diseases.
potentially life threatening due to the inflammation's proximity to the brain and spinal cord; it is therefore a medical emergency
symptoms
headache and neck stiffness
Fever, confusion or altered consciousness
inability to tolerate light (photophobia) or loud noises (phonophobia).
Sometimes, especially in small children, only nonspecific symptoms may be present, such as irritability and drowsiness.
If a rash is present, it may indicate a particular cause of meningitis (meningococcal bacteria
diagnosed by a spinal tap
must be treated promptly with antibiotics and sometimes antiviral drugs
In some situations, corticosteroid drugs can also be used to prevent complications from overactive inflammation.
can lead to serious long-term consequences such as deafness, epilepsy, hydrocephalus and cognitive deficit, especially if not treated quickly.
Some forms of meningitis may be prevented by immunization

12. CSF Provides supportive, protective cushioning
Reservoir of circulating fluid
Monitored by brain to detect changes in internal environment
Located in subarachnoid space and within cavities and canals of brain and spinal cord
Average adult has 140ml of CSF

13. Hydrocephalus “water head”
Sometimes in the unborn child, the drainage canal for CSF becomes stopped up.
The fluid builds up and the pressure causes the brain to expand like a balloon.
Causes the child to have a very large head and to be mentally retarded
Accompanies diseases (spina bifida, brain tumor, blood clots)
Possible coma or death

15. Spinal Cord Within spinal cavity (vertebral column)
Extends from foramen magnum to L1
Reflex center
Dorsal nerve root
carries sensory info into spinal cord
Ventral nerve root
carries motor info out of spinal cord
Interneurons – in s.c. gray matter
Spinal nerve – single mixed nerve on each side of s.c where dorsal and ventral nerve roots join

16. Spinal Cord Gray Matter Extends length of s.c
Consists of cell bodies of interneurons and motor neurons
Spinal reflex centers located here
Incoming sensory, outgoing motor
White Matter
Surrounds gray matter
Consists of axons

17. Spinal Cord

18. Brain One of largest organs in adults 3 lbs 6 major divisions
Medulla oblongata
Pons Brainstem
Midbrain
Cerebellum
Diencephalon
Cerebrum

19. Internal (Half) Brain
Optic chiasm

20. Brainstem Medulla Oblongata
Lowest part of brainstem
Attaches brain to s.c. just above foramen magnum
Reticular Formation – arousal, sleep (damaged=coma) [Reticular Activating System]
Controls breathing, heart rate and the activities of the gut
Coordinates swallowing, yawning, hiccuping, vomiting, coughing and sneezing
Injury often causes death

21. Brainstem Pons Between medulla and midbrain
motor control and sensory analysis
Regulate respiration

22. Brainstem Midbrain Above pons, below cerebrum
Auditory and visual centers
Muscular control

23. Cerebellum 2nd largest part of brain
Numerous sulci (grooves) and gyri (raised area)
Acts with cerebral cortex to produce skilled movements (coordination)
Controls skeletal muscles for balance
Controls posture
Subconscious level; automatic processor
Impulses travel from cerebellum to cerebrum and muscles to coordinate movement

24. Diencephalon Between cerebrum and midbrain Consists of Thalamus
Hypothalamus
Optic chiasma
Pineal body

25. Diencephalon Thalamus
Major relay station for sensory impulses on their way to cerebral cortex
Sensations
Conscious recognition of pain, temperature, touch
Relay sensory info (except smell) to cerebrum
Emotions of pleasant and unpleasantness
Complex reflexes

26. Diencephalon Hypothalamus
Below thalamus
Links mind and body
Regulates and coordinates autonomic activities
Synthesizes hormones secreted by pituitary gland
Water balance
Regulates appetite
Maintains normal body
temperature

27. Diencephalon Pineal Body
Regulates body’s biological clock
Produces some hormones
Melatonin

28. Cerebrum Cerebral cortex, cerebral tracts, cerebral nuclei.
Four general functions
Consciousness
Language
Emotions
Memory
Gyri (bumps) and sulci (shallow grooves)
Fissures – deep grooves, divides lobes
Longitudinal fissure – divides hemispheres
Central sulcus – between frontal and parietal lobes
Lateral fissure – between temporal and parietal lobes
Parietooccipital fissure – between occipital and parietal lobes
Outer surface made up of 6 layers of gray matter
Largest and uppermost
division of brain
Right and left hemispheres
Separated by corpus collosum
Each hemisphere has 4 lobes
Frontal
Parietal
Temporal
occipital
Parietooccipital fissure
Lateral fissure

29. Frontal lobe Prefrontal: Personality
And adaptation of the personality to events and experiences
Foresight and imagination
Sense of self
Frontal:
main motor areas (originate movement that is coordinated elsewhere)
Broca’s Area: speech production

30. Parietal lobe Principle sensory area Touch Proprioception
Lesions cause sensory losses
Involvement in cognition
Receptive speech loss

31. Temporal lobe Cognition Emotion Memory Auditory
Wernicke’s area: speech comprehension

32. Occipital lobe Vision Visual processing and visual association
Involved in eye movement

33. Limbic System emotion, behavior, long term memory, and olfaction
Set of brain structures that forms the inner border of the cortex
Corpus callosum: connects left and right hemispheres
Hippocampus: long-term memory; cognitive maps
Amygdala: reward, fear, mating

34. Right Hemisphere Left Hemisphere Language Dominating hand movements
Reasoning (tangible data)
Positive emotion
Hearing
Touch
Spatial relationships
Nonsymbolic data
Art
Spiritual
Negative emotions

38. Electroencephalogram
busy wave
EEG/ECG
Electroencephalogram
relaxed wave
drowsy wave
deep sleep wave

40. CNS Disorders Aphasia loss of speech
Hemiplegia, paraplegia, triplegia, quadriplegia
paralysis
Cerebral palsy
crippling disease involving permanent damage to motor control areas of the brain
Spastic paralysis
altered skeletal muscle performance in muscle tone involving hypertonia; it is also referred to as an unusual "tightness", stiffness, or "pull" of muscles
 lack of inhibition results in excessive contraction of the muscles, ultimately leading to hyperflexia (overly flexed joints)
Presents in multiple sclerosis and other CNS disorders
CVA (cerebrovascular accident) aka Stroke
cessation or hemorrhage of blood causing neuronal damage
Dementia
Alzheimer’s: inherited form of dementia (early signs around age 30-40)
Huntington’s Disease: affects memory in middle to late adulthood, causing cortex lesions
AIDS
Seizures
Epilepsy

41. Effectors = skeletal muscles
PNS
Nerves
Somatic NS
Voluntary
Effectors = skeletal muscles
Autonomic NS
Involuntary
Sympathetic
Motor System
“Fight or Flight”
Parasympathetic
“Rest and Repose”

42. Somatic Nervous System
Contraction of skeletal muscles
Skeletal muscle = somatic effector
All voluntary motor pathways outside of CNS
Neurotransmitter = ACh

43. Reflexes All voluntary motor pathways outside of CNS Reflexes
Action resulting from nerve impulse passing over a reflex arc
Predictable response to stimuli
Autonomic Reflex
Visceral
Contraction of smooth or cardiac muscle
Secretion of glands
Somatic Reflex
Contraction of skeletal muscles

44. Somatic Reflexes Contraction of skeletal muscles
Reflexes deviate from normal in certain conditions
Reflex testing is valuable diagnostic tool
Patellar Reflex: extension of lower leg
Achilles Reflex: extension of foot
Babinski Reflex: extension of big toe
Present until age 1.5
If present after, indicates damage to corticospinal fibers
Plantar Reflex: flexion of all toes and slight turning in of foot
Corneal Reflex: wink when touch cornea
Abdominal Reflex: stroke side of abdomen causes drawing in of abdominal wall

45. Knee-Jerk (Patellar) Reflex

46. Autonomic Nervous System
Involuntary/Visceral body functions
Cardio, resp, dig, urogen
Maintain homeostasis by: regulating heartbeat, smooth muscle contraction, glandular secretions
Conduct impulses from CNS to autonomic effectors
Two divisions
Sympathetic
Parasympathetic

47. Autonomic Conduction Pathway

48. Parasympathetic Nervous System
“Feed-or-Breed”
“Rest-and-Repose”
Counteracts Sympathetic
“Fight-or-Flight”
Allows body to function under stress

50. ANS Neurotransmitters
Norepinephrine (adrenaline)
Adrenergic fibers
release norepinephrine in postsynaptic sympathetic neurons
Acetylcholine (ACh)
Cholinergic fibers
release ACh in presynaptic sympathetic neurons
release ACh in pre and post parasympathetic neurons

52. Norepinephrine
Affects visceral effectors by binding to adrenergic receptors
Alpha receptor: blood vessels constrict
Beta receptor: blood vessels dilate
Inhibiting action of norepinephrine
MAO (monoamine oxidase): enzyme that breaks up norepinephrine that is taken up by synaptic knobs

54. ACh Binds to cholinergic receptors Inhibiting action of Ach
Nicotinic receptors
Muscarinic receptors
Inhibiting action of Ach
acetylcholinesterase