Divisions of the Nervous System

• Nervous System is divided into...

  Central Nervous System

  Peripheral Nervous System
• Part of the central nervous system

  • Brain
  • Spinal cord
• The peripheral nervous system is further divided into....

  • Somatic nervous system
  • Autonomic nervous system
• What makes up the Autonomic Nervous System

  • Sympathetic nervous system
  • Parasympathetic nervous systems
• Nervous system

  Collection of neurons across the body that detects information from the environment and processes this, then directs the body to take action via the muscles and glands
• Central nervous system (CNS)

  • Responsible for our complex processing
  • Brain: the centre of all conscious and most unconscious processing
  • spinal cord: this receives and transmits information
• Peripheral nervous system (PNS)

  • The portion of the nervous system that is outside the brain and spinal cord
  • Primary function is to connect the brain and spinal cord to the rest of the body and the external environment
• Components of the peripheral nervous system

  • Somatic nervous system
  • Autonomic nervous system
• Somatic nervous system (SNS)

  • Connects the central nervous system with the senses
  • Composed of sensory nerve pathways bringing information to the CNS from sensory receptors
  • Composed of motor nerve pathways which control bodily movement by carrying instructions towards muscles
• The Autonomic nervous system acts largely unconsciously

  • It controls bodily arousal, body temperature, homeostasis, heart rate and blood pressure
  • Composed of the sympathetic and parasympathetic nervous systems
• The Sympathetic Nervous System is involved in preparing the body for fight or flight, so causes increased arousal (e.g. increase in heart rate and blood pressure, pupil dilation, reduction in digestion and salivation)
• The parasympathetic nervous system is used to return our body back to its normal state after the fight or flight response, so leads to decreased arousal
• Under normal conditions there is a balance between the sympathetic and parasympathetic systems in order to maintain homeostasis