Biopsychology: The PNS - Somatic and Autonomic Nervous Systems

Overview

• Peripheral Nervous System (PNS): Relays messages (nerve impulses) from the Central Nervous System (CNS) to the rest of the body.
• Components of PNS:
  1. Somatic Nervous System
  2. Autonomic Nervous System

Somatic Nervous System

• Facilitates communication between the CNS and the external environment.
• Composed of:
  • Sensory receptors: Carry information to the spinal cord and brain.
  • Motor pathways: Control movement and provide muscle responses.
• Function: Transmits sensory information from the outside world to the brain and enables motor responses.

Autonomic Nervous System

• Maintains homeostasis: Regulates internal processes such as body temperature, heart rate, and blood pressure.
• Composed solely of motor pathways.
• Subdivisions:
  1. Sympathetic Nervous System
  2. Parasympathetic Nervous System

Sympathetic Nervous System

• Prepares the body for fight or flight responses.
• Effects: Increases heart rate, blood pressure, and breathing rate; suppresses digestion, salivation, and urination.

Parasympathetic Nervous System

• Relaxes the body and returns it to a normal resting state post stress.
• Effects: Slows heart rate and breathing rate, reduces blood pressure, and restores digestion and other functions slowed during fight or flight.

AQA A Level Essays on Biopsychology

• Additional resources for students studying A-Level Psychology, focusing on core topics related to biopsychology. Available as digital resources.