Nervous System Overview

Nervous System Overview

• The nervous system is a complex network responsible for coordinating bodily functions and responding to stimuli.
• It is divided into two main parts: Central Nervous System (CNS) and Peripheral Nervous System (PNS).

Central Nervous System (CNS)

• Comprises the brain and spinal cord.

• Functions:

  • Processes sensory information.
  • Coordinates motor control.
  • Responsible for higher cognitive functions (e.g., thinking, memory).

• Major Structures:

  • Brain: Divided into:

    • Cerebrum: Responsible for thought, memory, and voluntary movement.
    • Cerebellum: Coordinates balance and fine motor skills.
    • Brainstem: Controls basic life functions (breathing, heart rate).

  • Spinal Cord: Transmits signals between the brain and body; responsible for reflex actions.

Peripheral Nervous System (PNS)

• Comprises all nerves outside the CNS.
• Divided into:
  • Somatic Nervous System: Controls voluntary movements and transmits sensory information.
  • Autonomic Nervous System: Regulates involuntary bodily functions; further divided into:
    • Sympathetic Nervous System: Prepares body for fight or flight response.
    • Parasympathetic Nervous System: Promotes rest and digest functions.

Neurotransmission

• The process by which signaling molecules (neurotransmitters) are released by a neuron and transmitted to target cells.

• Key Steps in Neurotransmission:

  1. Action Potential: Electrical signal travels along the neuron.
  2. Release of Neurotransmitters: Upon reaching the synaptic terminal, neurotransmitters are released into the synaptic cleft.
  3. Binding to Receptors: Neurotransmitters bind to specific receptors on the postsynaptic neuron.
  4. Response Generation: Binding can result in excitatory or inhibitory responses in the postsynaptic neuron.
  5. Reuptake or Breakdown: Neurotransmitters are either reabsorbed by the presynaptic neuron or broken down by enzymes to terminate the signal.

• Common Neurotransmitters:

  • Acetylcholine: Involved in muscle activation and memory.
  • Dopamine: Regulates pleasure, reward, and motor control.
  • Serotonin: Affects mood, emotion, and sleep.
  • Norepinephrine: Involved in arousal and stress responses.

• Important Concepts:

  • Synapse: The junction between neurons where neurotransmission occurs.
  • Neuroplasticity: The ability of the nervous system to adapt and change in response to experience.

Nervous System Overview

• The nervous system serves as the body's control center, coordinating activities and responses to stimuli.
• It's divided into the Central Nervous System (CNS) and the Peripheral Nervous System (PNS).

Central Nervous System (CNS)

• The CNS comprises the brain and spinal cord, responsible for processing information and controlling bodily functions.
• The brain, the command center, is divided into the cerebrum, cerebellum, and brainstem, each with specialized roles.
  • The cerebrum governs higher cognitive functions like thinking, memory, and voluntary movement.
  • The cerebellum coordinates balance and fine motor skills.
  • The brainstem controls essential life functions like breathing and heart rate.
• The spinal cord acts as a communication highway, transmitting signals between the brain and the rest of the body. It also mediates reflex actions.

Peripheral Nervous System (PNS)

• The PNS encompasses all the nerves outside the CNS, connecting it to the body.
• Divided into the somatic and autonomic nervous systems.
  • The somatic nervous system controls voluntary movements and transmits sensory information, allowing for conscious control.
  • The autonomic nervous system regulates involuntary bodily functions, operating without conscious awareness.
  • The autonomic nervous system branches into the sympathetic and parasympathetic systems.
  • The sympathetic system prepares the body for "fight or flight" responses, increasing heart rate and adrenaline release in stressful situations.
  • The parasympathetic system promotes "rest and digest" functions, slowing heart rate and facilitating digestion.

Neurotransmission

• Neurotransmitters play a crucial role in communication within the nervous system.
• This communication happens in a series of steps:
  • An action potential, an electrical impulse, travels along the neuron.
  • When the impulse reaches the synaptic terminal, neurotransmitters are released into the synaptic cleft, the space between neurons.
  • These neurotransmitters bind to specific receptors on the postsynaptic neuron, triggering a response.
  • Binding can have either an excitatory (promoting signal transmission) or inhibitory (suppressing signal transmission) effect on the postsynaptic neuron.
  • After completing their task, neurotransmitters are either reabsorbed by the presynaptic neuron (reuptake) or broken down by enzymes.

Common Neurotransmitters

• Acetylcholine: Involved in muscle activation and memory formation.
• Dopamine: Regulates pleasure, reward, and motor control; imbalances are associated with conditions like Parkinson's disease.
• Serotonin: Affects mood, emotion, and sleep; imbalances are linked to depression and anxiety.
• Norepinephrine: Involved in arousal and stress responses.

Important Concepts

• Synapse: The junction between neurons where neurotransmission takes place.
• Neuroplasticity: The nervous system's ability to adapt and change in response to experiences, learning, and injury.

Explore the intricate structure and functions of the nervous system, which includes the Central Nervous System (CNS) and the Peripheral Nervous System (PNS). This quiz covers major features, including brain structures and their roles in coordinating bodily functions and cognitive processes.