Nervous System Flashcards
Neuromuscular system
The connection to the brain and spinal cord through a network of nerves circuits
Functions of the nervous system
To gather and store information and to control various bodily functions in response to said information
Nervous system structures
CNS and peripheral nervous system (PNS)
CNS
Brain and spinal cord; control center of the nervous system, responsible for receiving sensory input and formulating responses to the information
Components of the peripheral nervous system (PNS)
All nervous structures outside the CNS, namely the nerves and ganglia
Ganglia
Nerve cell bodies associated with the nerves
Peripheral nervous system divisions
Efferent division and Afferent division
Afferent (sensory) decision
Carries nerve impulses to the CNS from receptors located in the skin, fasciae, joints, and visceral organs
Efferent (motor) division
Handles outgoing information and is divided into the somatic and autonomous nervous systems
Somatic nervous system
Carries nerve impulses from the CNS to skeletal muscles and is under conscious control, outside of reflex response
Autonomous nervous system
Generally subconscious, made of the nerves that transmit impulses to smooth muscles, cardiac muscles, and glands; further divided into the sympathetic and parasympathetic system
Sympathetic nervous system
Causes the body to stop storing and mobilize all energy when under stress or emergency (fight or flight syndrome)
Parasympathetic nervous system
Aids in controlling normal functions such as digestion, energy storage, and growth well the body is at rest
Neuron
A nerve cell, the most basic structural and functional component of the nervous system
Soma
A cell body
Neuron processes
Fibrous extensions (axons and dendrites) from the soma of a neuron
Dendrites
Conduct electrical impulses toward the cell body
Axons
Transmit electrical signals away from the cell body
Synapse
Small space between neurons
Proprioception
Awareness of the body in relation to various segments and the external environment
Proprioceptors
Receptors in the skin, in and around the joints and muscles, and in the inner ear that gather sensory information to achieve kinesthetic awareness
Cutaneous receptors
Receptors in the skin that sends sensory information regarding pressure, touch, and movement of the hairs on the body
Joint receptors
Send information regarding position, velocities, and acceleration at the joint
Pacinian corpuscles
Deep receptors in the skin and joints sensitive to pressure
Meissner’s corpuscles
Receptors in the superficial layers of skin responsive to soft touch
Golgi-mazzoni corpuscles
Located within the joint capsule, responsive to joint compression and stimulated by any weight-bearing activity
Musculotendinous receptors
Receptors involved in muscular control, coordination, and contribute to the body sense of postural control
Golgi tendon organ (GTO), muscle spindle
Autogenic inhibition
The automatic reflex relaxation caused by stimulation of the Golgi tendon organ
Reciprocal inhibition
The reflex inhibition of the motor neurons of antagonists when the agonists are contracted
Muscle spindle
Stretches when the muscle itself is under force triggering a reflex contraction in the muscle known as stretch reflex which allows the antagonist muscle group to relax
Golgi tendon organ (GTO)
Senses increased tension within its associated muscle as the muscle contracts or stretches and functions to cause an inhibition of the contraction resulting in an enhanced contraction of the antagonist muscle group
Vestibular system
Three fluid-containing semicircular canals at right angles to each other and sensory hairs to detect movement of the fluid within head
