neuro 2620

• Brain


  The human nervous system, consisting of neurons (specialized and connected to other neurons, neural processing) and glial cells (supports the neurons)

  
• Components of the nervous system

  • Central Nervous System (CNS)
  • Peripheral Nervous System (PNS)
• Major structures of the brain

  • Cerebrum (forebrain)
  • Brainstem
  • Cerebellum

  
• Cerebrum


  • Hemispheres
  • Neocortex
• Cerebral Protection


  • The brain's surface is covered by a triple-layered covering called the meninges, and the cerebrospinal fluid (CSF) cushions the brain and spinal cord

  
• Behaviour


  Patterns in time, including movement, vocalizations, and thinking
• Ethology


  The study of animal behaviour
• Types of animal behaviour

  • Inherited (innate, fixed)
  • Learned (plastic)
• A crossbill's beak is specifically designed to open pine cones, an example of innate behaviour
• A baby rat learning from its mother to eat pine cones is an example of learned behaviour
• The brain's primary function


  • Receiving information about the world
  • Integrating information to construct a subjective experience of reality (perception)
  • Producing commands to control the movement of muscles
• Evolution created adaptations, equipping each species with a view of the world that helps it survive
• Neuroplasticity


  The brain's capacity to adapt to the world by constantly changing how its functions are organized

  
• Phenotypic plasticity


  The brain's ability to change its structure and function in response to experience

  
• Afferent information


  Incoming information to the Central Nervous System
• Efferent information


  Outgoing information from the Central Nervous System
• There is a lack of coherence in the nomenclature for brain structure, with multiple names, numbers, and letters used interchangeably
• Frames of reference for describing brain structure locations

  • Brain-body orientation
  • Spatial orientation
  • Anatomical orientation

  
• Brain-body orientation terms


  • Dorsal (up)
  • Ventral (down)
  • Anterior (front)
  • Posterior (behind)
  • Lateral (away from midline)
  • Medial (toward midline)

  
• Spatial orientation terms


  • Rostral (away from beak)
  • Caudal (away from tail)
  • Ventral (inferior, down)
  • Dorsal (superior, up)
• Anatomical orientation planes


  • Coronal section
  • Horizontal section
  • Sagittal section
• Anatomical orientation views


  • Frontal
  • Dorsal
  • Medial
• Anatomical location and orientation terms


  • Anterior
  • Caudal
  • Coronal
  • Dorsal
  • Frontal
  • Horizontal
  • Interior
  • Lateral
  • Lateral
  • Medial
  • Posterior
  • Rostral
  • Sagittal
  • Superior
  • Ventral
• Surface features of the brain

  • Cerebrum
  • Cerebellum: "little brain"
  • Gyrus (pl. Gyri)
  • Sulcus (pl. Sulci)
  • Fissure
  • Brainstem

  
• The brain's surface is covered with blood vessels, and the three major arteries that feed blood to the cerebral hemispheres branch extensively to supply the regions
• Stroke occurs with blockage or break in a cerebral artery
• The brain's internal features

  • Gray matter
  • White matter
  • Corpus callosum
• Cerebral ventricles


  Lateral ventricles: winged-shaped cavities filled with cerebrospinal fluid (CSF) made by a network of interconnected blood vessels
• Cerebrospinal fluid (CSF)


  Suspends the brain, acts as a shock absorber, and provides protection from mild head blows, as well as providing a stable environment for optimal brain function
• Sagittal brain section


  • Reveals the brain's midline structures, including the subcortical structures ventral to the corpus callosum

  
• Neurons


  Connected to one another by fibers called axons
• Tract


  A collection of nerve fibers in the brain and spinal cord
• Nerve


  A bundle of fibers outside the Central Nervous System
• Spinal cord


  • Controls most body movements, can act independently of the brain, and is responsible for spinal reflexes
• Spinal reflex characteristics


  • Automatic movement
  • Hard to prevent (brain cannot inhibit)
• The knee-jerk reflex (patellar tendon) is an example of a spinal reflex
• Brainstem regions


  • Hindbrain
  • Midbrain
  • Diencephalon

  
• Hindbrain


  • Evolutionarily the oldest part of the brain, contains the cerebellum, reticular formation, pons, and medulla, and controls various motor functions ranging from breathing to balance to fine movements

  
• The size of the human cerebellum is related to cognitive capacity
• Hindbrain subparts


  • Reticular formation (reticular activating system)
  • Pons
  • Medulla