What are the two major divisions of the nervous system?
- Central nervous system (CNS)
- Peripheral nervous system (PNS)
The CNS comprises the brain and spinal cord, while the PNS includes all neurons outside the CNS.
The central nervous system comprises which two main components?
- Brain
- Spinal cord
The CNS processes information from the environment and formulates responses.
What is the role of the brain in the nervous system?
Coordinates mental processes and behavior; regulates bodily activity
Considered the control center of the body.
What is the function of the spinal cord?
Transmits neural messages between the brain and the peripheral nervous system
Composed of afferent tracts (sensory) and efferent tracts (motor).
The peripheral nervous system is divided into which two systems?
- Somatic nervous system
- Autonomic nervous system
The PNS transmits neural messages between the CNS and the body.
What does the somatic nervous system control?
Voluntary motor movement
Comprises sensory and motor neural pathways.
What is the role of the autonomic nervous system?
Regulates visceral muscles, organs, and glands
Transmits neural messages to the CNS about their activity.
What are the three types of neurons?
- Motor neurons
- Sensory neurons
- Interneurons
Motor neurons transmit messages from the CNS to the body; sensory neurons transmit messages from the body to the CNS.
Define conscious responses.
Deliberate and voluntary actions initiated by the brain
Involve the CNS and the somatic nervous system.
Define unconscious responses.
Automatic and involuntary actions performed without awareness
Include physiological responses and spinal reflexes.
What is a spinal reflex?
An unconscious response initiated from sensory stimuli by interneurons in the spinal cord
Involves a reflex arc transmitting sensory and motor messages.
What is the role of neurotransmitters?
Transmit neural information across a synapse
Can produce excitatory or inhibitory effects.
What are the two types of neurotransmitters?
- Excitatory neurotransmitters
- Inhibitory neurotransmitters
Excitatory neurotransmitters increase the likelihood of action potential; inhibitory neurotransmitters decrease it.
What is glutamate known for?
Main excitatory neurotransmitter in the nervous system
Plays an important role in learning and memory.
What is GABA known for?
Main inhibitory neurotransmitter in the nervous system
Regulates postsynaptic activation and prevents overexcitation of neurons.
What are neuromodulators?
Chemical molecules affecting multiple postsynaptic neurons
Produce long-lasting effects and modulate neurotransmitter activity.
What is synaptic plasticity?
Ability of synaptic connections to change over time in response to activity or exp.
Involves mechanisms like sprouting, rerouting, and pruning.
What is long-term potentiation?
Long-lasting strengthening of synaptic connections due to frequent use
Involves structural changes and increased neurotransmitter release.
What is long-term depression?
Long-lasting weakening of synaptic connections due to infrequent use
Involves decreased neurotransmitter release and structural changes.
