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Questions and Answers
Which receptors send a signal as long as a stimulus continues to be present and does not ease or fatigue with time?
In the peripheral somatosensory system, which neurons are in the thalamus and communicate to the cerebral cortex?
What type of receptors will quickly adapt to a signal that is being sent and will fatigue or stop responding despite the presence of an ongoing stimulus?
Which part of the nervous system works on a three-order neuronal pathway for a signal to be sent to the periphery?
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Which receptors are aware the same as the autonomic nervous system and can be classified as tonic or phasic?
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Which nervous system component allows us to sense things such as temperature, pain, pressure, or stretch?
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Where are the 2nd order neurons located in the three-order neuronal pathway for a signal to be sent to the periphery?
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Which part of the nervous system includes the sympathetic and parasympathetic nervous systems?
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Which of the following structures is NOT a part of the Pain Matrix?
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What is the primary function of the Pain Matrix?
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Which neurotransmitter is responsible for inhibiting the transmission of nociceptive signals in the spinothalamic tract?
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What term is used to describe the phenomenon where an area of the spinal cord is altered or injured, leading to suboptimal integration and regulation of signals?
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Which modality can facilitate the release of enkephalin through the interneurons in the dorsal horn?
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What is the term used to describe the top-down inhibition of pain signals?
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Which area of the brain is responsible for the mediation of pain sensation by the emotional and motivational systems?
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What term is used to describe the phenomenon where all areas of the brain become active in response to a single painful stimulus?
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Which part of the nervous system is responsible for the actual experience of pain?
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What term is used to describe the phenomenon where a stimulus is likely to induce a pain response where normally it does?
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Which modality can prevent the activation of nociceptors throughout the body?
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Which area of the brain can intensify the experience of pain input?
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What type of information do muscle spindles provide?
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What is the role of Golgi tendon organs?
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What type of information does the intact sensory system provide to the brain?
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What is the function of the homunculus on the primary somatosensory cortex?
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What type of information do conscious relay paths carry to the cerebral cortex?
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What distinguishes nonconscious relay pathways?
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What is the role of alpha and gamma motor neurons in muscle spindle activation?
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Where are Golgi tendon organs located?
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What do joint receptors play active roles in detecting?
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What type of information do divergent paths carry toward the brainstem and cerebrum?
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Which type of nerve endings sense coarse touch, pain, and temperature?
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Which type of nerve ending is positioned to sense stretch?
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What type of neurons are the largest in diameter and fastest in signal transmission speed?
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What do muscle spindles provide information on?
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Which type of receptor senses fine details of touch?
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What is crucial for physical therapists to know for testing sensation and identifying lesions or problems in the body?
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What do Pacinian corpuscles respond to?
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What are receptive fields in the hands compared to those in the torso?
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What is sensory innervation categorized as?
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What do sensory nerve conduction studies measure?
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What is the basis for regional sensation?
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What is important for differential diagnosis and impairment testing?
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Which tract carries information on crude touch in the anterolateral column?
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Where do signals from upper body or arms travel in the dorsal column-medial lemniscus system?
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Where does the spinoreticular tract terminate?
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Which tract targets periaqueductal gray and superior colliculus on the midbrain?
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Where do signals from upper trunk and upper limb go in the dorsal column-medial lemniscus system?
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Which tract carries information on discriminative pain and temperature in the anterolateral column?
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Where do signals from legs travel in the dorsal column-medial lemniscus system?
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Where do signals from upper body or arms travel in the anterolateral column?
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Where do divergent tracts convert pain signals?
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Where do signals from upper body or arms travel in the anterolateral column?
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What is the role of a motor unit?
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What is the primary function of muscle synergies in a healthy normal system?
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What is the process of reciprocal inhibition in muscle contraction?
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What is the significance of the spinal level in the movement of a joint?
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What is the function of alpha motor neurons in muscle spindle activation?
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What is the term used to describe the phenomenon where there is a complete disconnect between the midbrain and pons, resulting in extension of arms and flexion of wrists?
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Which type of lesion results in a lack of muscle activation, hypotonia, hyporeflexia, and areflexia?
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What is the term used to describe the resistance within a muscle being stretched, which can be either normal or abnormal?
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Which of the following is a characteristic of an upper motor neuron lesion?
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What is the term used to describe the change in muscle due to altered neuromuscular activity or prolonged position, leading to shortened muscle or contracture?
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Which type of nerve ending is positioned to sense stretch?
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Where are Golgi tendon organs located?
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Which motor tracts are responsible for controlling posture and muscle innervation?
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What is the function of the nonspecific motor tracts, such as the ceruleospinal and raphespinal tracts?
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What type of information do muscle spindles provide?
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Where are the cell bodies for the medial corticospinal tract located?
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Which tract responds to signals coming from the inner ear, helping orient the body towards gravity?
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Where do the Lateral Tracts in the spinal cord primarily target?
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Where do the Rubrospinal Tract cell bodies originate?
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Which motor system dysfunction involves repeated, involuntary, rhythmic contractions of a single muscle group?
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What is the term used to describe the group of muscles innervated by a single spinal nerve?
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Which region of the spinal cord is important for the assigned movement of a joint?
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What is the term used to describe the phenomenon where one muscle contracts, leading to the inhibition of the antagonist muscle to prevent injury?
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What term is used to describe the coordinated timing, degree, and inhibition of muscle action in a healthy normal system?
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What is the term used to describe the resistance within a muscle being stretched, which can be either normal or abnormal?
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Where are the cell bodies for the lateral corticospinal tract located?
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What is the primary function of the rubrospinal tract?
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Which tract primarily innervates distal limb movement and fractionation of movements?
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Where do signals from the inner ear travel in the spinal cord?
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What is the function of the medial motor tracts?
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Which of the following is not a characteristic of myoplasticity?
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What is the term used to describe a phenomenon where there is a complete disconnect between the midbrain and pons, resulting in extension of arms and flexion of wrists?
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What is the primary difference between upper motor neuron lesions and complete motor neuron lesions?
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What is the term used to describe the resistance within a muscle being stretched, which can be either normal or abnormal?
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What is the characteristic presentation of a lower motor neuron lesion?
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Which structure is responsible for informing about tendon tension and lengthening, affecting muscle activation through spinal interneurons?
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What initiates a reflex in the spinal cord by activating afferent nerves?
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What type of reflex coordinates muscle activation in response to a noxious stimulus, occurring at multiple spinal levels without the need for cortical input?
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Which test locates areas of damage along muscle activation, helping to identify problems in motor nerves, neuromuscular junctions, or muscles?
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Which type of motor tracts are responsible for controlling posture and muscle innervation?
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What is a motor unit?
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What is the function of muscle synergies in a healthy normal system?
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What is the role of reciprocal inhibition in muscle contraction?
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What is the significance of the spinal level in the movement of a joint?
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What is the function of the myotome in the motor system?
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Which type of reflex coordinates muscle activation in response to a noxious stimulus, occurring at multiple spinal levels without the need for cortical input?
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What is the function of the medial motor tracts, including the reticulospinal, medial vestibulospinal, and lateral vestibulospinal tracts?
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What type of lesion results in heightened muscle activity with needle electromyography?
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What do vertical motor tracts within the spinal cord convey signals for?
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What is the role of the Golgi tendon organ in muscle activation?
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Which of the following is a characteristic of a lower motor neuron lesion?
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What is the term used to describe a phenomenon where there is a complete disconnect between the midbrain and pons, resulting in extension of arms and flexion of wrists?
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What distinguishes an upper motor neuron lesion from a complete motor neuron lesion?
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What type of motor system dysfunction involves repeated, involuntary, rhythmic contractions of a single muscle group?
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What is crucial for physical therapists to know for testing sensation and identifying lesions or problems in the body?
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Where are the cell bodies for the lateral corticospinal tract located?
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What is the primary role of the Rubrospinal Tract?
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What is the distinguishing feature of the Medial Motor Tracts?
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What is the function of the Reticulospinal Tract?
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What is the primary function of the Lateral Vestibulospinal Tract?
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What is a motor unit?
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What is the role of reciprocal inhibition in muscle contraction?
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What does a myotome refer to?
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What is the function of muscle synergies?
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What is the term used to describe the resistance within a muscle being stretched, which can be either normal or abnormal?
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What is the term used to describe the phenomenon where there is a complete disconnect between the midbrain and pons, resulting in extension of arms and flexion of wrists?
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What is the primary difference between upper motor neuron lesions and complete motor neuron lesions?
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What is the term used to describe the change in muscle due to altered neuromuscular activity or prolonged position, leading to shortened muscle or contracture?
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Which term refers to the phenomenon where there is a complete disconnect between the midbrain and pons, resulting in extension of arms and flexion of wrists?
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What is the primary function of the rubrospinal tract?
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What distinguishes an upper motor neuron lesion from a complete motor neuron lesion?
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What is the role of reciprocal inhibition in muscle contraction?
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What type of neurons are the largest in diameter and fastest in signal transmission speed?
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What is important for differential diagnosis and impairment testing?
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What is the term used to describe the phenomenon where there is an abnormal increase in resistance within a muscle being stretched?
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What is the primary function of muscle synergies in a healthy normal system?
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Where are the cell bodies for the Medial Corticospinal Tract located?
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Which tract primarily innervates axial and girdle musculature, facilitating posture and core strength?
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Where do signals from the inner ear travel to, in order to orient the body towards gravity?
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Where do the cell bodies for the Lateral Corticospinal Tract originate?
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Which tract begins in the reticular formation of the brainstem and sends signals to both ipsilateral and contralateral motor neurons at the spinal level?
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Which motor system dysfunction involves repeated, involuntary, rhythmic contractions of a single muscle group?
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Where do the Medial Motor Tracts arise from within the cortex?
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Which tract primarily innervates distal limb movement and fractionation of movements?
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Where does the Rubrospinal Tract begin?
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Which tract responds to signals regarding head movement and position, activating and coordinating muscle activity in the neck and upper back?
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Which tract starts at the premotor cortex and descends downwards through the spinal cord?
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Where are the cell bodies for the Reticulospinal Tract located?
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What type of signaling provides proprioception, informing about the body's position in space and time?
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Which structure informs about tendon tension and lengthening, affecting muscle activation through spinal interneurons?
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What is responsible for coordinating a rudimentary stepping pattern by connecting sensory and motor signals at or near the spinal level?
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What type of stretch activates afferent nerves to the spinal cord, initiating a reflex?
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Which reflex coordinates muscle activation in response to a noxious stimulus, occurring at multiple spinal levels without the need for cortical input?
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What tests locate areas of damage along muscle activation, helping to identify problems in motor nerves, neuromuscular junctions, or muscles?
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What measures electric activity in muscles, aiding in understanding the location of lesions in the motor nervous system?
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What results in heightened muscle activity with needle electromyography?
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What can be identified through electromyography and nerve conduction studies?
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Which motor tracts convey signals for movement and muscle activation to different parts of the body?
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Which motor tracts are responsible for controlling posture and muscle innervation?
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Which motor tracts form the emotional motor system, impacting movement in response to emotions?
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What is a motor unit?
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What is the function of reciprocal inhibition in muscle contraction?
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What is the role of muscle synergies in a healthy normal system?
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Why is communication of sensory, motor & interneurons important?
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What is the term used to describe the resistance within a muscle being stretched, which can be either normal or abnormal?
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What is the characteristic presentation of a lower motor neuron lesion?
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Where are the cell bodies for the lateral corticospinal tract located?
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What type of reflex coordinates muscle activation in response to a noxious stimulus, occurring at multiple spinal levels without the need for cortical input?
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What is the term used to describe the phenomenon where there is a complete disconnect between the midbrain and pons, resulting in extension of arms and flexion of wrists?
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What is the term used to describe the group of muscles innervated by a single spinal nerve?
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What is the role of reciprocal inhibition in muscle contraction?
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What is the primary function of the rubrospinal tract?
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What do Pacinian corpuscles respond to?
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What is the term used to describe the phenomenon where all areas of the brain become active in response to a single painful stimulus?
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What is the function of the medial motor tracts?
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What measures electric activity in muscles, aiding in understanding the location of lesions in the motor nervous system?
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What is the primary function of the Golgi tendon organ?
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Which reflex coordinates muscle activation in response to a noxious stimulus without the need for cortical input?
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What does electromyography measure in muscles?
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What can be identified through nerve conduction studies?
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Which motor tracts are responsible for controlling posture and muscle innervation?
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What do motor neuron lesions result in with needle electromyography?
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What is the primary function of the vertical motor tracts within the spinal cord?
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What is the role of the nonspecific motor tracts, such as the ceruleospinal and raphespinal tracts?
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What do medial motor tracts primarily innervate?
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What is the function of the lateral vestibulospinal tract?
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Where do signals from the legs primarily travel in the dorsal column-medial lemniscus system?
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What is the basis for regional sensation in the nervous system?
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Where are the cell bodies for the medial corticospinal tract located?
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Which tract responds to signals coming from the inner ear, helping orient the body towards gravity?
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What is the primary function of the rubrospinal tract?
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Which motor tracts arise in the primary motor cortex and supplementary motor area within the cortex?
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What is the role of the lateral corticospinal tract?
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What type of motor control is primarily coordinated at the brainstem level?
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Which tract begins in the reticular formation of the brainstem, sending signals to both ipsilateral and contralateral motor neurons at the spinal level?
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What does the lateral vestibulospinal tract respond to?
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Which tracts are responsible for distal limb movement and fractionation of movements?
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Where does the lateral corticospinal tract start?
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What is the primary role of the medial vestibulospinal tract?
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What type of motor system dysfunctions include paresis vs paralysis and abnormal reflexes like Babinski's sign?
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Study Notes
Sensory Pathways in the Spinal Cord: Dorsal Column-Medial Lemniscus vs. Anterolateral Column
- Dorsal column-medial lemniscus system conveys high fidelity information on light touch and conscious proprioception
- Signals from lower trunk or legs go to ipsilateral nucleus cuneatus; signals from upper trunk and upper limb go to ipsilateral nucleus gracilis in the lower medulla
- Signals from legs travel up the dorsal column medially in the fasciculus gracilis tract; signals from upper body or arms travel more laterally in the fasciculus cuneatus tracts
- Signals then decussate in the medial lemniscus to target the contralateral VPL nucleus of the thalamus before reaching the contralateral primary somatosensory cortex
- Anterolateral Column contains conscious relay tracts like spinothalamic tract and divergent tracts like spinomesencephalic, spinoreticular, and spino-emotional tracts
- Spinothalamic tract carries information on discriminative pain and temperature; lateral spinothalamic tract carries discriminative pain and temperature, while anterior spinothalamic tract carries crude touch
- Signals travel through dorsal root ganglion to dorsal horn of spinal cord, then to contralateral VPL nucleus of thalamus, and finally to the primary somatosensory cortex on the same side as the VPL nucleus
- Divergent tracts convert pain signals with low fidelity and speed, targeting various areas in the cortex such as prefrontal cortex, parietal vortices, and the insula
- Spinomesencephalic tract targets periaqueductal gray and superior colliculus on the midbrain to draw attention to painful stimulus
- Spinoreticular tract terminates in the reticular formation of the midbrain, interacting with areas responsible for attention, arousal, and sleep-wake cycles
- All three divergent tracts convey signals for slow, vague, pain sensations, targeting various parts of the contralateral brain, thalamus, and midbrain, and traveling up the spinal cord along with the spinothalamic tract
- The spinothalamic tract conveys information on discriminate pain and temperature to the contralateral primary somatosensory cortex, with signals immediately decussating within the spinal cord
Motor Tracts and Dysfunctions in the Spinal Cord
- Medial corticospinal tract primarily innervates axial and girdle musculature, facilitating posture and core strength
- Cell bodies for these tracts are located in the medial anterior horn of the gray area of the spinal cord
- Automatic motor control primarily coordinated at the brainstem level, where these 3 tracts derive
- Reticulospinal Tract begins in the reticular formation of the brainstem, sending signals to both ipsilateral and contralateral motor neurons at the spinal level
- Lateral Vestibulospinal Tract responds to signals coming from the inner ear, helping orient the body towards gravity
- Medial Vestibulospinal Tract responds to signals regarding head movement and position, activating and coordinating muscle activity in the neck and upper back
- Medial Motor Tracts arise in the primary motor cortex and supplementary motor area within the cortex, providing signals for bilateral control of axial and upper girdle muscles
- Lateral Tracts in the spinal cord responsible for distal limb movement and fractionation of movements
- Lateral Corticospinal Tract starts at the premotor cortex, descending downwards through the spinal cord
- Rubrospinal Tract begins at the red nucleus in the midbrain and plays a smaller role than the lateral corticospinal tract
- Motor System Dysfunctions include paresis vs paralysis, abnormal reflexes like Babinski's sign, and phasic stretch hyperreflexia
- Motor System Dysfunctions also include tonic stretch reflex and clonus, which are repeated, involuntary, rhythmic contractions of a single muscle group
Motor System: Spinal Cord and Nerve Assessment
- Type 2 afferent signaling from periphery, interneurons, and motor neurons provides proprioception, informing about the body's position in space and time.
- The Golgi tendon organ informs about tendon tension and lengthening, affecting muscle activation through spinal interneurons.
- A rudimentary stepping pattern is coordinated by a highway of interneurons connecting sensory and motor signals at or near the spinal level.
- Phasic stretch, such as the reflex hammer stretch to the patellar tendon, activates afferent nerves to the spinal cord, initiating a reflex.
- The withdrawal/crossed extension reflex coordinates muscle activation in response to a noxious stimulus, occurring at multiple spinal levels without the need for cortical input.
- Motor nerve conduction velocity tests locate areas of damage along muscle activation, helping to identify problems in motor nerves, neuromuscular junctions, or muscles.
- Electromyography measures electric activity in muscles, aiding in understanding the location of lesions in the motor nervous system.
- Motor neuron lesions result in heightened muscle activity with needle electromyography, while motor tract lesions may present with degeneration in specific tracts.
- Myopathy, damage to the muscle itself, can be identified through electromyography and nerve conduction studies.
- Vertical motor tracts within the spinal cord convey signals for movement and muscle activation to different parts of the body.
- Medial motor tracts, including the reticulospinal, medial vestibulospinal, and lateral vestibulospinal tracts, are responsible for controlling posture and muscle innervation.
- Nonspecific motor tracts, such as the ceruleospinal and raphespinal tracts, form the emotional motor system, impacting movement in response to emotions.
Motor Tracts and Dysfunctions in the Spinal Cord
- Medial corticospinal tract primarily innervates axial and girdle musculature, facilitating posture and core strength
- Cell bodies for these tracts are located in the medial anterior horn of the gray area of the spinal cord
- Automatic motor control primarily coordinated at the brainstem level, where these 3 tracts derive
- Reticulospinal Tract begins in the reticular formation of the brainstem, sending signals to both ipsilateral and contralateral motor neurons at the spinal level
- Lateral Vestibulospinal Tract responds to signals coming from the inner ear, helping orient the body towards gravity
- Medial Vestibulospinal Tract responds to signals regarding head movement and position, activating and coordinating muscle activity in the neck and upper back
- Medial Motor Tracts arise in the primary motor cortex and supplementary motor area within the cortex, providing signals for bilateral control of axial and upper girdle muscles
- Lateral Tracts in the spinal cord responsible for distal limb movement and fractionation of movements
- Lateral Corticospinal Tract starts at the premotor cortex, descending downwards through the spinal cord
- Rubrospinal Tract begins at the red nucleus in the midbrain and plays a smaller role than the lateral corticospinal tract
- Motor System Dysfunctions include paresis vs paralysis, abnormal reflexes like Babinski's sign, and phasic stretch hyperreflexia
- Motor System Dysfunctions also include tonic stretch reflex and clonus, which are repeated, involuntary, rhythmic contractions of a single muscle group
Motor System: Spinal Cord and Nerve Assessment
- Type 2 afferent signaling from periphery, interneurons, and motor neurons provides proprioception, informing about the body's position in space and time.
- The Golgi tendon organ informs about tendon tension and lengthening, affecting muscle activation through spinal interneurons.
- A rudimentary stepping pattern is coordinated by a highway of interneurons connecting sensory and motor signals at or near the spinal level.
- Phasic stretch, such as the reflex hammer stretch to the patellar tendon, activates afferent nerves to the spinal cord, initiating a reflex.
- The withdrawal/crossed extension reflex coordinates muscle activation in response to a noxious stimulus, occurring at multiple spinal levels without the need for cortical input.
- Motor nerve conduction velocity tests locate areas of damage along muscle activation, helping to identify problems in motor nerves, neuromuscular junctions, or muscles.
- Electromyography measures electric activity in muscles, aiding in understanding the location of lesions in the motor nervous system.
- Motor neuron lesions result in heightened muscle activity with needle electromyography, while motor tract lesions may present with degeneration in specific tracts.
- Myopathy, damage to the muscle itself, can be identified through electromyography and nerve conduction studies.
- Vertical motor tracts within the spinal cord convey signals for movement and muscle activation to different parts of the body.
- Medial motor tracts, including the reticulospinal, medial vestibulospinal, and lateral vestibulospinal tracts, are responsible for controlling posture and muscle innervation.
- Nonspecific motor tracts, such as the ceruleospinal and raphespinal tracts, form the emotional motor system, impacting movement in response to emotions.
Motor System: Spinal Cord and Nerve Assessment
- Type 2 afferent signaling from periphery, interneurons, and motor neurons provides proprioception, informing about the body's position in space and time.
- The Golgi tendon organ informs about tendon tension and lengthening, affecting muscle activation through spinal interneurons.
- A rudimentary stepping pattern is coordinated by a highway of interneurons connecting sensory and motor signals at or near the spinal level.
- Phasic stretch, such as the reflex hammer stretch to the patellar tendon, activates afferent nerves to the spinal cord, initiating a reflex.
- The withdrawal/crossed extension reflex coordinates muscle activation in response to a noxious stimulus, occurring at multiple spinal levels without the need for cortical input.
- Motor nerve conduction velocity tests locate areas of damage along muscle activation, helping to identify problems in motor nerves, neuromuscular junctions, or muscles.
- Electromyography measures electric activity in muscles, aiding in understanding the location of lesions in the motor nervous system.
- Motor neuron lesions result in heightened muscle activity with needle electromyography, while motor tract lesions may present with degeneration in specific tracts.
- Myopathy, damage to the muscle itself, can be identified through electromyography and nerve conduction studies.
- Vertical motor tracts within the spinal cord convey signals for movement and muscle activation to different parts of the body.
- Medial motor tracts, including the reticulospinal, medial vestibulospinal, and lateral vestibulospinal tracts, are responsible for controlling posture and muscle innervation.
- Nonspecific motor tracts, such as the ceruleospinal and raphespinal tracts, form the emotional motor system, impacting movement in response to emotions.
Motor Tracts and Dysfunctions in the Spinal Cord
- Medial corticospinal tract primarily innervates axial and girdle musculature, facilitating posture and core strength
- Cell bodies for these tracts are located in the medial anterior horn of the gray area of the spinal cord
- Automatic motor control primarily coordinated at the brainstem level, where these 3 tracts derive
- Reticulospinal Tract begins in the reticular formation of the brainstem, sending signals to both ipsilateral and contralateral motor neurons at the spinal level
- Lateral Vestibulospinal Tract responds to signals coming from the inner ear, helping orient the body towards gravity
- Medial Vestibulospinal Tract responds to signals regarding head movement and position, activating and coordinating muscle activity in the neck and upper back
- Medial Motor Tracts arise in the primary motor cortex and supplementary motor area within the cortex, providing signals for bilateral control of axial and upper girdle muscles
- Lateral Tracts in the spinal cord responsible for distal limb movement and fractionation of movements
- Lateral Corticospinal Tract starts at the premotor cortex, descending downwards through the spinal cord
- Rubrospinal Tract begins at the red nucleus in the midbrain and plays a smaller role than the lateral corticospinal tract
- Motor System Dysfunctions include paresis vs paralysis, abnormal reflexes like Babinski's sign, and phasic stretch hyperreflexia
- Motor System Dysfunctions also include tonic stretch reflex and clonus, which are repeated, involuntary, rhythmic contractions of a single muscle group
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your understanding of sensory pathways in the spinal cord with this quiz. Explore the differences between the dorsal column-medial lemniscus and anterolateral column systems, and grasp their roles in conveying touch, proprioception, and pain signals to the brain.