Neural Communication and Neurotransmitters

Neural Communication

• Neurons are the basic units of the nervous system, responsible for electrochemical communication.
• Sensory neurons transmit information from sensory receptors to the brain/spinal cord.
• Motor neurons transmit information from the brain/spinal cord to muscles and glands.
• Interneurons connect sensory and motor neurons within the brain and spinal cord.
• Neurons transmit signals via axons and receive signals through dendrites.
• Action potentials are electrical impulses that travel down axons.
• The "all-or-none" principle means neurons either fire or don't fire.
• Neurotransmitters are chemical messengers that travel across synapses.
• Reuptake is the process where the sending neuron absorbs excess neurotransmitters.

Neurotransmitters and Their Effects

• Neurotransmitters have specific paths and effects on behavior/emotions.
• Acetylcholine influences muscle action, learning, and memory.
• Endorphins are natural pain relievers and are linked to pleasure.
• Drugs can either excite (agonists) or inhibit (antagonists) neurotransmission.

Key Terminology

• Myelin sheath: Fatty tissue that speeds up neural impulses.
• Action potential: Electrical impulse.
• Threshold: Level of stimulation needed to trigger an action potential.
• Synapse: Junction between neurons.
• Neurotransmitters: Chemical messengers.
• Reuptake: Reabsorption of neurotransmitters.
• Endorphins: Natural pain relievers.

Structure and Function of the Nervous System

• Nervous system includes central and peripheral nervous systems.
• CNS: brain and spinal cord.
• PNS: sensory and motor neurons connecting CNS to the body.
• Nerves: Bundled axons forming neural cables.
• Somatic Nervous System: Controls skeletal muscles.
• Autonomic Nervous System: Controls glands and internal organs.
  • Sympathetic: Arouses the body.
  • Parasympathetic: Calms the body.

Brain Structures

• Brainstem: Oldest part of the brain—controls basic life functions.
  • Medulla: Regulates heartbeat and breathing.
  • Reticular formation: Important for arousal.
• Thalamus: Sensory switchboard, directing sensory input.
• Cerebellum: Coordinates movement and balance.
• Limbic system: Associated with emotions and drives.
  • Amygdala: Linked to emotion.
  • Hypothalamus: Regulates bodily functions (eating, drinking, temperature).
• Cerebral cortex: Outer layer of the brain; ultimate control and information processing center.
  • Glial cells: Support, nourish, and protect neurons.
  • Frontal lobes: Involved in speaking, planning, and judgment.
  • Parietal lobes: Receive sensory input for touch and body position.
  • Occipital lobes: Receive visual information.
  • Temporal lobes: Process auditory information.
  • Motor cortex: Controls voluntary movements.
  • Sensory cortex: Processes sensory information.
  • Association areas: Higher-level mental functions (learning, memory, etc.).

Brain Imaging Techniques

• PET scan: Detects brain activity by glucose use.
• MRI: Produces images of soft tissue in the brain.
• fMRI: Measures brain activity by detecting blood flow.

Other Key Concepts

• Plasticity: Brain's ability to change and reorganize.
• Neurogenesis: Formation of new neurons.
• Corpus callosum: Connects the two brain hemispheres.
• Split brain: Condition where the hemispheres are isolated.

Explore the fascinating world of neural communication through this quiz. Test your knowledge on the roles of different types of neurons, action potentials, and neurotransmitters in influencing behavior and emotions. Understand how these chemical messengers affect learning, memory, and pain relief.