Hyperreflexia
Encyclopedia
Hyperreflexia is defined as overactive or overresponsive reflexes. Examples of this can include twitching
or spastic
tendencies, which are indicative of upper motor neuron disease as well as the lessening or loss of control ordinarily exerted by higher brain
centers of lower neural pathways (disinhibition). See Autonomic dysreflexia
.
(see autonomic dysreflexia
). Standard stimuli like the filling of the bladder can cause excessive responses from the nervous system, such causes are not known.
But hyperreflexia can be developed via many other causes, including medication and stimulant side effects, electrolyte
imbalance, serotonin syndrome
and severe brain trauma.
Muscle contraction
Muscle fiber generates tension through the action of actin and myosin cross-bridge cycling. While under tension, the muscle may lengthen, shorten, or remain the same...
or spastic
Spastic
The word spastic is used differently depending on location which has led to some controversy and misunderstanding. Derived via Latin from the Greek spastikos , the word originally referred to a change in muscles affected by the medical condition spasticity, which is seen in spastic diplegia and...
tendencies, which are indicative of upper motor neuron disease as well as the lessening or loss of control ordinarily exerted by higher brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
centers of lower neural pathways (disinhibition). See Autonomic dysreflexia
Autonomic dysreflexia
Autonomic dysreflexia, "AD" also known as "autonomic hyperreflexia or Hyperreflexia, is a potentially life threatening condition which can be considered a medical emergency requiring immediate attention. AD occurs most often in spinal cord-injured individuals with spinal lesions above the T6 spinal...
.
Causes
The most common cause of hyperreflexia is spinal cord injurySpinal cord injury
A spinal cord injury refers to any injury to the spinal cord that is caused by trauma instead of disease. Depending on where the spinal cord and nerve roots are damaged, the symptoms can vary widely, from pain to paralysis to incontinence...
(see autonomic dysreflexia
Autonomic dysreflexia
Autonomic dysreflexia, "AD" also known as "autonomic hyperreflexia or Hyperreflexia, is a potentially life threatening condition which can be considered a medical emergency requiring immediate attention. AD occurs most often in spinal cord-injured individuals with spinal lesions above the T6 spinal...
). Standard stimuli like the filling of the bladder can cause excessive responses from the nervous system, such causes are not known.
But hyperreflexia can be developed via many other causes, including medication and stimulant side effects, electrolyte
Electrolyte
In chemistry, an electrolyte is any substance containing free ions that make the substance electrically conductive. The most typical electrolyte is an ionic solution, but molten electrolytes and solid electrolytes are also possible....
imbalance, serotonin syndrome
Serotonin syndrome
Serotonin syndrome is a potentially life-threatening adverse drug reaction that may occur following therapeutic drug use, inadvertent interactions between drugs, overdose of particular drugs, or the recreational use of certain drugs...
and severe brain trauma.