Module 2

• Cognitive neuroscience is the study of the physiological basis of cognition
• Three principle functions of the nervous system:

  • Sensory input
  • Integration
  • Motor input
• Focus is on basic principles of nervous system functioning and the structure and functioning of cells
• Nervous system division:

  • Central nervous system includes the brain and spine cord
  • Peripheral nervous system is around the body
  • Sensory division (afferent) picks up sensory stimuli
  • Motor division (efferent) sends directions from the brain to muscles and glands
  • Somatic nervous system is voluntary (skeletal movement)
  • Autonomic nervous system is involuntary (heart, stomach, lungs)
  • Sympathetic sends the body into action
  • Parasympathetic relaxes the body
• The brain:

  • A 3.5-pound structure considered as the seat of the mind
  • Static tissue with no moving parts
  • Doesn't expand or contract
  • Appears almost solid when observed with the naked eye
• Localization of function:

  • Specific functions are served by specific areas of the brain
• Localization for perception:

  • Primary receiving areas for the senses are located in specific lobes of the cerebral cortex
• Brain imaging:

  • Positron emission tomography (PET) measures brain activity by tracking blood flow
  • Functional magnetic resonance imaging (fMRI) measures blood flow without radioactive tracers
  • Used to determine which areas of the brain are activated during cognitive tasks
• Localization for language:

  • Broca's area in the frontal lobe is specialized for producing language
  • Wernicke's area in the temporal lobe is associated with language comprehension
  • Broca's aphasia and Wernicke's aphasia are conditions resulting from damage to these areas
• Neurons:

  • Basic functional unit of the nervous system
  • Neurons are irreplaceable and have high energy demands
  • Parts of a neuron:
  • Dendrites: receive information inputs
  • Axon: transmits information away from the cell body
  • Cell body/soma: center for nourishment
• Neuron types:

  • Multipolar neurons have three or more processes
  • Bipolar neurons have one axon and one dendrite
  • Unipolar neurons have only one process
• Neuron functions:

  • Sensory neurons (afferent) transmit impulses from sensory receptors to the CNS
  • Motor neurons (efferent) transmit impulses from the CNS to the rest of the body
  • Interneurons (association neurons) transmit impulses between sensory and motor neurons
• Glial cells/neuroglia:

  • Provide support, nutrition, insulation, and help with signal transmission in the nervous system
  • Types of glial cells in the central nervous system and peripheral nervous system
• Temporal lobe: auditory receiving area
• Occipital lobe: vision
• Parietal lobe: skin senses (touch, temperature, pain)
• Frontal lobe: receives signals from all senses and coordinates information from multiple senses