Lesson 3: The Anatomy of Nervous System

• Neuroanatomy


  The anatomy of nervous system and the study of the various parts of the nervous system & their respective function(s).
• What are the functions of the Nervous System?

  • Sensory function
  • Integrative function
  • Motor function
• Sensory function


  Nervous system uses its millions of sensory receptors to monitor changes occurring both inside and outside of the body. Those changes are called "stimuli", and the gathered information is called "sensory input".
• Integrative function


  The nervous system process and interprets the sensory input and makes decisions about what should be done at each moment - a process called "integration".
• Motor function


  The nervous system then send information to muscles, glands, and organs (effectors) so they can respond correctly, such as muscular contradiction or glandular secretions.
• What are the basic types of cells present in the nervous system?

  • Neurons/nerve cell
  • Glial cells
• Neurons


  • Are the main structural and functional units of the nervous system.
  • Every neuron consists of a body (soma) and a number of processes (neurites).
• What are the structural types of neurons?

  • Multipolar
  • Bipolar
  • Pseudounipolar
  • Unipolar
• Glial cells


  It is the non-neuronal cells that support and protect neurons in the nervous system.
• What are the two (2) divisions of the nervous system?

  • Central nervous system
  • Peripheral nervous system
• Central nervous system


  • The control center of the body.
  • Consists of the brain and spinal cord.
  • Interpret incoming sensory information and issue instructions based on past experience and current conditions.
• Peripheral nervous system


  • Consists of bundles of nerves between the spinal cord and the rest of the body.
• The brain


  • One of the largest and most complex organs in the human body.
  • Made up of more than 100 billion nerves that communicate in trillions of connections called "synapses".
• What are the MAJOR DIVISIONS of the brain?

  • Forebrain
  • Midbrain
  • Hindbrain
• What are the (7) Forebrain structures?

  • Cerebral cortex
  • Cingulategyrus
  • Corpus callosum
  • Thalamus (limbic system)
  • Hypothalamus (limbic system)
  • Hippocampus (limbic system)
  • Amygdala (limbic system)
• It is the largest part of the brain covered by the cerebral cortex. It also regulates senses, memory, emotions, intellectual activities and body movements.

  
  

  CEREBERUM
• Cerebral Cortex


  • Is responsible for processing information that is divided into 2 hemispheres.
• Limbic System


  • It controls basic emotions and psychological drives, it is made up of a number of different structures but the three (3) of the most important are the hippocampus, amygdala and the hypothalamus.
• Amygdala


  • The critical component of the limbic system.
  • An almond-shape set of neurons responsible for processing fear.
• Thalamus


  • A sensory relay for the brain.
  • All our senses, with the exception of smell, are routed through the thalamus before directed to other areas of the brain for processing.
  • Considered to be the neural railway station of the brain. It is also involved with consciousness, alertness and sleep.
• Hypothalamus


  • It is located at the base of the brain near the pituitary gland.
  • Involved with pleasure, food, body temperature and sex.
  • Regulates the pituitary gland and other hormone-releasing glands in the body. It is referred as "master gland" of the endocrine system".

  Examples:

  • If the body temperature gets too high, the hypothalamus instructs the body to sweat. If the body is cold, the ______ will cause shivers. Irregular hypothalamic behavior can, in turn, lead to sweating and shivering when these reactions are not needed.
• What are the (4) four lobes of the brain?

  • Frontal lobe
  • Parietal lobe
  • Temporal lobe
  • Occipital lobe
• Frontal Lobe


  • Involves voluntary movement, reasoning, impulse control, language, and speech.
• Phineas Gage is often referred to as the "man who began neuroscience"
• Phineas Gage experienced a traumatic brain injury when an iron rod was driven through his skull, destroying much of his frontal lobe.
• The impact of Phineas Gage's accident has helped us better understand what the frontal lobe does, especially in relation to personality.
• Parietal Lobe


  • Mainly involved with processing the sense of touch, limb position, and spatial awareness.
  • Damage to the _____ lobe typically involves loss of these abilities in the parts of the body opposite the lesion.
• Temporal lobe


  • Primarily processes auditory stimuli.
  • The ______ lobe communicates with the hippocampus to produce long-term memory.
• Occipital Lobe


  • Located at the rear end of the cerebral cortex and is known to be the visual processing center of the brain.
  • Damage can cause an inability to identify colors, loss of visual capacity, and even hallucinations.
• MIDBRAIN


  • Helps to regulate movement and process auditory and visual information.
• What are the parts of the MIDBRAIN?

  • Colliculi
  • Tegmentum
  • Cerebral peduncles
• HINDBRAIN

  • Helps to regulate autonomic functions, relay sensory information, coordinate movement, and maintain balance and equilibrium.
  • It is located at the back of the head and looks like an extension of the brain.
  • It is mostly coordinates autonomic functions that are essential to survival.
  • It contains the medulla oblongata, pons, and cerebellum.
• Medulla Oblongata

  • The lowest part of the brainstem and the primary connection to the nervous system.
  • It is primarily Involved in breathing, heart rate, digestion, swallowing, heart rhythms and sneezing.
  • It also controls the automatic processes of the autonomic nervous system such as breathing, blood pressure and heart rate.
• Pons


  • Which is latin for "bridge".
  • A group of nerves involved in arousal, sleep, motor control and muscle tone.
• Cerebellum


  • Latin for "little brain".
  • Receives messages from muscles, tendons, joints and structures in our ear to control balance, coordination and movement and facilitate motor learning.
  • Thought to be an important area for processing procedural memory.
  • Most disorders of the ______ are associated with serious motor impairment.
• Spinal Cord


  It is a reflex center and conduction pathway which is found within the vertebral canal, extending from foramen magnum to L1 or 12. Part of the CNS found within the spinal column and communicates with the sense organs and muscles below the level of the head.
• The Spinal Cord is Comprised of (2):

  
  

  Gray matter & White matter
• Motor/Efferent Neurons


  Carries impulses from the CNS to effectors organs, muscles, and glands.
• Sensory/Afferent Neurons


  Consist of nerve fibers that convey impulses to the CNS from sensory receptors located in various parts of the body. Sensory fibers that deliver impulses from the skin, skeletal muscles, and joints called somatic (soma = body) sensory fibers. Sensory fibers that transmit impulses from the visceral organs called visceral sensory fibers or visceral afferents. Keeps the CNS constantly informed of events going both inside and outside the body.
• What are the types of Sensory Fibers?

  
  

  Motor/Efferent Neurons & Sensory/Afferent Neurons