Nervous system

• Central Nervous System


  Includes the brain and spinal cord
• Peripheral Nervous System


  Consists of all nerves and ganglia outside the CNS
• Sensory nervous system


  Afferent nervous system
• Motor nervous system


  Efferent nervous system
• Somatic motor nervous system


  From CNS to voluntary muscles
• Autonomic motor nervous system


  From CNS to involuntary muscles
• Sympathetic autonomic nervous system


  Fight or flight
• Parasympathetic autonomic nervous system


  Rest and digest
• Enteric Nervous System


  Has motor and sensory neurons contained wholly in the digestive tract
• Multipolar neurons


  Most neurons
• Bipolar neurons


  Found in the retina and nasal cavity
• Pseudo unipolar neurons


  Found in the dorsal root ganglion
• Astrocytes


  Major supporting cell, blood-brain barrier
• Ependymal cells


  Produces CSF
• Microglia


  Immune cells
• Oligodendrocytes


  Myelin sheath of the CNS
• Schwann cells


  Myelin sheath of the PNS
• Multiple sclerosis


  Potentially disabling disease of the brain and spinal cord
• Multiple sclerosis - the immune system attacks the protective sheath (myelin) that covers axons
• Gray matter


  40% of the brain, contains most of the brain's neuronal cell bodies, serves to process information, fully develop once a person reaches his 20's
• White matter


  60% of the brain, made of bundles which connects various gray matter areas, develop throughout the 20's and peaks in middle age
• Saltatory conduction


  Action potential appears to jump from node to node
• Acetylcholine


  A neurotransmitter for memory and cognitive function. It also gives bowel tone.
• Norepinephrine


  A neurotransmitter for attention, motivation, pleasure, and reward.
• Dopamine


  The reward chemical. A neurotransmitter for alertness and energy.
• Serotonin


  The mood stabilizer. It helps to regulate mood and behavior, appetite, digestion, sleep, memory, and sexual drive.
• Oxytocin


  The love hormone.
• Endorphin


  It works as pain killer and are released after exercise.
• Major depression is characterized by intense feelings of sadness.
• Dysthymic disorder is a less intense type of depression, but it persists for a longer period of time (years).
• Adjustment disorders occur when an individual's response to a stressful event.
• Postpartum depression is depression that occurs after giving birth.
• Manic depression or bipolar disorder is a brain disorder that causes unusual shifts in a person's mood.
• Psychotic depression includes some features of psychosis, such as hallucinations or delusions.
• Seasonal affective disorder (SAD) is a type of depression that comes on in the winter months when the sun is sparse.
• Alzheimer's disease: most common form of dementia and is associated with a decrease in Acetylcholine-secreting neurons.
• Myasthenia gravis: results from reduction in acetylcholine receptors
• Botulism: caused by toxin of Clostridium botulinum and blocks the release of acetylcholine from the presynaptic terminal.
• Cocaine: acts by inhibiting the reuptake of norepinephrine.
• Morphine: mimics endorphins, the "happy hormone".