Organization of the nervous system

• What are the main functions of the nervous system?

  Sensory perception , motor coordination , learning and memory , motivation and thought
• What do the functions depend on?

  Precise connections formed among different types of neurons , main properties of the nervous tissue: excitability and conductivity.
• What is the organization of the nervous system?

  Sensory systems , motor systems and association systems
• What is gray matter

  cell bodies and neuropil in the brain and spinal cord
• What is white matter


  axon tracts and commissures
• What are the three cardinal planes of the brain?

  Axial, coronal and sagittal
• What are the main subdivisions of the central nervous system?

  Spinal cord , brain
• What are the cellular layers of the embryo?

  Endoderm , mesoderm and ectoderm
• From which layer does the nervous system arise from?

  Ectoderm
• What are the divisions of the neuronal tube?

  Alar plate (sensory structure) and basal plate (Motor structure)
• What are the main subdivisions of the embryonic central nervous system?

  Prosencephalon , Mesencephalon , rhombencephalon
• What are the layers of the brain?

  dura mater, arachnoid , pia mater
• What is the spinal cord structure?

  Protected by the backbone, and it extends from the base of the skull to the first lumbar vertebra
• What are the sections of the spinal cord segments?

  Cervical , thoratic , lumbar and sacral
• What is the role of the spinal cord?

  Prominent role in perception and action , it facilitates the interaction of sensory and motor systems
• How many spinal nerves are there, and what is the function?

  31 spinal nerves that receive sensory information from the skin, joints and muscles of the trunk and limbs
• What are the four main types of neurons in the spinal cord?

  Spinal interneurons (axons that terminate exclusively in the spinal cord) , projection neurons , motor neurons (axons that leave the cord to innervate skeletal muscles) and pre-ganglionic neurons (innervate autonomic ganglia)
• Spinal cord structure?

  Outer part(white matter): axons running up and down spinal and supraspinal and inner part (gray matter): cell bodies of spinal neurons
• What are the functions of the structures in the spinal cord?

  dorsal part : sensory input

  Ventral part: motor output
• What types of neurons are in the ventral horn?

  Motor neurons (Lamina IX) regulated by interneurons (Lamina VII)
• What are the types of motor neurons in mammals?

  Alpha: Fast conduction velocities , axon splits into dozens of terminal branches near the target muscle, each terminal branch innervated one large extrafusal striated muscle fiber via a specialized synapse called the neuromuscular function

  
  

  Gamma: Innervate intrafusal muscle fibers
• What are Renshaw cells?

  Inhibitory interneurons that receive colaterals from motor neurons
• What are the divisions in the ANS?


  Sympathetic , parasympathetic and enteric nervous system
• What is the enteric division?

  Sensory and motor neurons in the gastrointestinal tract that mediate digestive reflexes
• What type of neurons are located in the sympathetic division?

  Pre-ganglionic neurons are located in thoracic and lumbar regions of the spinal cord
• What type of neurons are located in the parasympathetic division?

  Pre-ganglionic neurons are located in the brain stem and sacral region of the spinal cord
• What structures are in the brainstem?

  Pons , midbrain , medulla oblongata
• What are the main structures of the brainstem?

  Reticular formation (core with local circuit interneurons) , neuronal nuclei (generate cranial nerves) , Relay nuclei (for sensory and motor tracts)
• How many cranial nerves?

  12 cranial nerves
• What is the function of the medulla?

  Regulation of blood pressure and respiration , nucleus involved in taste, hearing , balance and motor control of neck and face
• What are the types of nuclei located in the medulla?

  Vestibulary nuclei (Information about equilibrium) , Olivary nuclei (coordinates of motor information from the spinal cord to the cerebellum) and Medullary pyramid (motor tracts)
• What is the function of the pons?

  coordinates motor information from the cerebral cortex to the cerebellum (pontine nuclei) and involved in respiration , taste and sleep
• What is the function of the midbrain?


  Coordinates motor system components
• What is the structure of the pons?

  Cerebellar peduncles that connect brainstem with cerebellum
• What is substancia nigra and where is it located?

  It is located in the midbrain, and it is involved in motor coordination
• What is the function of the cerebellum?

  motor learning skills , fine tuning movements , regulatio of equilibrium , important for maintaining posture and coordination of head an eye movements and involved in language and cognitive function
• What are the activity patterns of the cerebellum?

  Thalamus and cerebral cortex- ascending outputs

  
  

  Brainstem - descending outputs
• What is the structure of the cerebellum?

  primary fissure (anterior/posterior lobe) and posterolateral fissure (flocculondular lobe)
• What are the 5 main type of neurons in the cerebellar cortex?

  stellate , basket , purkinje , golgi and granule neurons
• What are the cortical layers?

  Molecular (Stellate , basket cells , dendrites from purkinje cells , parallel fibers from granule neurons , climbing fibers) , Purkinje cell layer (purkinje cell somas) , Granular layer (Granule neurons , golgi cells , mossy fibers)