Peripheral Nervous System Flashcards
Somatosensory system Neural Integration Sensory System Nerves and associated ganglis (14 cards)
Describe the role of sensation in survival.
Sensation is the awareness of changes in the internal and external environment, which is crucial for survival.
Explain the difference between sensation and perception.
Sensation refers to the awareness of stimuli, while perception is the conscious interpretation of those stimuli.
Define the somatosensory system.
The somatosensory system is part of the sensory system that serves the body wall and limbs.
Identify the types of receptors that provide inputs to the somatosensory system.
Inputs come from exteroceptors, proprioceptors, and interoceptors.
How is sensory input processed in the nervous system?
Sensory input is relayed toward the head and processed at various levels, including receptor, circuit, and perceptual levels.
What are the three levels of neural integration in sensory systems?
The three levels are receptor level (sensory receptors), circuit level (processing in ascending pathways), and perceptual level (processing in cortical sensory areas).
Differentiate between spinal and cranial nerves.
Spinal nerves originate from the spinal cord, while cranial nerves originate from the brain.
Explain the classification of nerves based on impulse direction.
Nerves are classified as mixed, sensory (afferent), or motor (efferent) based on the direction they transmit impulses.
Define a nerve in the context of the peripheral nervous system (PNS).
A nerve is a cordlike organ of the PNS, consisting of a bundle of myelinated and nonmyelinated peripheral axons enclosed by connective tissue.
What are mixed nerves?
Mixed nerves contain both sensory and motor fibers, allowing impulses to travel both to and from the CNS.
Describe sensory (afferent) nerves.
Sensory (afferent) nerves carry impulses only toward the CNS.
What are motor (efferent) nerves?
Motor (efferent) nerves carry impulses only away from the CNS.
Explain the rarity of pure sensory and pure motor nerves.
Pure sensory (afferent) or pure motor (efferent) nerves are rare; most nerves are mixed, containing both types of fibers.
Identify the types of fibers found in mixed nerves.
Mixed nerves contain somatic afferent (sensory from muscle to brain), somatic efferent (motor from brain to muscle), visceral afferent (sensory from organs to brain), and visceral efferent (motor from brain to organs) fibers.
