Neurotransmitters

Definition

Neurotransmitters are chemical messengers that transmit signals across synapses from one neuron to another or to target tissues. They play a crucial role in facilitating communication within the nervous system and are vital for various physiological processes, including mood regulation, motor control, and cognitive functions.

5 Must Know Facts For Your Next Test

1. There are many types of neurotransmitters, including acetylcholine, dopamine, serotonin, and norepinephrine, each serving different functions in the body.
2. Neurotransmitters can be excitatory, promoting the transmission of nerve impulses, or inhibitory, preventing the transmission of impulses.
3. The balance of neurotransmitters is crucial for maintaining mental health; imbalances can lead to disorders such as depression and anxiety.
4. Neurotransmitters are released from vesicles in the presynaptic neuron and bind to receptors on the postsynaptic neuron, initiating a response.
5. Some neurotransmitters can also act as hormones and influence bodily functions beyond the nervous system, impacting areas like metabolism and immune response.

Review Questions

• How do neurotransmitters facilitate communication between neurons?
  • Neurotransmitters facilitate communication between neurons by being released from vesicles in the presynaptic neuron into the synapse, where they bind to specific receptors on the postsynaptic neuron. This binding can either promote or inhibit the generation of action potentials in the receiving neuron, effectively transmitting signals throughout the nervous system. Different neurotransmitters have distinct effects based on their receptor interactions.
• Discuss the roles of excitatory and inhibitory neurotransmitters in neural signaling.
  • Excitatory neurotransmitters enhance neural signaling by increasing the likelihood that the postsynaptic neuron will generate an action potential, while inhibitory neurotransmitters decrease this likelihood. This balance between excitation and inhibition is essential for proper brain function and helps regulate activities such as muscle contraction, mood regulation, and overall cognitive processes. Disruptions in this balance can lead to various neurological conditions.
• Evaluate how imbalances in neurotransmitter levels can affect mental health and behavior.
  • Imbalances in neurotransmitter levels can significantly impact mental health and behavior by altering mood, perception, and cognitive function. For instance, low levels of serotonin are often linked to depression and anxiety disorders, while imbalances in dopamine are associated with conditions such as schizophrenia and addiction. Understanding these relationships allows for targeted treatment strategies that aim to restore balance through medications or lifestyle changes that influence neurotransmitter levels.

Related terms

Synapse: The junction between two neurons where neurotransmitters are released to transmit signals.

Receptors: Protein molecules located on the surface of neurons that bind neurotransmitters, triggering a response in the receiving cell.

Action Potential:

A temporary reversal of the electrical potential across a neuron's membrane, leading to the propagation of an electrical signal along the neuron.