What Is The Gate Control Theory? How Is It Similar To A Florida Intercoastal Drawbridge?

Pain perception varies across dissimilar individuals according to their mood, emotional condition and prior feel, fifty-fifty if the pain is caused by similar physical stimuli and results in a like degree of damage. In 1965, Ronald Melzack and Patrick Wall outlined a scientific theory well-nigh psychological influence on pain perception; the 'gate control theory'.

If not for this theory, pain perception would be notwithstanding associated with the intensity of the pain stimulus and the caste of impairment caused to the afflicted tissue. But Melzack and Wall fabricated it evident that pain perception is far more complex.

Co-ordinate to the gate control theory, hurting signals are not free to attain the brain as shortly as they are generated at the injured tissues or sites. They demand to encounter sure 'neurological gates' at the spinal cord level and these gates determine whether the pain signals should reach the brain or non. In other words, pain is perceived when the gate gives fashion to the hurting signals and it is less intense or non at all perceived when the gate closes for the signals to laissez passer through. This theory gives the explanation for why someone finds relief past rubbing or massaging an injured or a painful surface area.

Though the gate command theory cannot present the consummate picture show of the central arrangement that underlies hurting, it has visualized the mechanism of hurting perception in a new dimension and information technology has paved the fashion for various pain direction strategies.

Peripheral nerve fibers involved in transmission of sensory signals

Every organ or part of the human body has its own nerve supply and the nerves deport the electrical impulses generated in response to various sensations like touch, temperature, pressure and pain. These nerves – that constitute the peripheral nervous organisation – transmit these impulses to the fundamental nervous system (the brain and spinal cord) and then that these impulses are interpreted and perceived as sensations. The peripheral fretfulness ship signals to the dorsal horn of the spinal cord and from there the sensory signals are transmitted to the brain through the spinothalamic tract. Pain is a sensation that alerts a person that a tissue or a particular office of the human body has been injured or damaged.

According to the axonal diameter and the conduction velocity, nerve fibers can be classified into 3 types – A, B and C. The C fibers are the smallest among all the three types. Among the 'A' fibers are four subtypes: A-alpha, A-beta, A-gamma and A-delta. Amid the A subtypes, the A-alpha fibers are the largest and the A-delta fibers are the smallest.

The A fibers that are larger than the A-delta fibers, carry sensations like bear upon, pressure, etc. to the spinal cord. The A-delta fibers and the C fibers behave pain signals to the spinal cord. A-delta fibers are faster and carry sharp pain signals while the C fibers are slower and acquit diffuse pain signals.

When considering the conduction velocity, the A-alpha fibers (the large nervus fibers) take higher conduction velocity when compared to the A-delta fibers and the C fibers (small nervus fibers). When a tissue is injured, the A-delta fibers are activated first, followed by the activation of the C fibers. These fibers tend to acquit the pain signals to the spinal cord and then to the encephalon. But the hurting signals are non transmitted simply like that.

What does the gate control theory say?

The gate control theory suggests that the signals encounter 'nervus gates' at the level of the spinal cord and they need to go cleared through these gates to accomplish the brain. Various factors determine how the pain signals should exist treated at the neurological gates. They are:

• The intensity of the pain signals
• The intensity of the other sensory signals (touch, temperature and pressure), if generated at the site of injury
• The bulletin from the brain itself (to send the pain signals or not)

As already mentioned, the nerve fibers, large and small, conveying the sensory signals, cease in the dorsal horn of the spinal cord from where the signals are transmitted to the encephalon. According to the original postulate of Melzack and Wall, the nervus fibers project to the substantia gelatinosa (SG) of the dorsal horn and the first cardinal transmission (T) cells of the spinal string. The SG consists of inhibitory interneurons that deed as the gate and decide which signals should reach the T cells and so become further through the spinothalamic tract to reach the encephalon.

When the pain signals carried by the small-scale fibers (A-delta and C fibers) are less intense compared to the other non-pain sensory signals similar touch, pressure and temperature, the inhibitory neurons prevent the transmission of the hurting signals through the T cells. The non-hurting signals override the pain signals and thus the pain is not perceived past the brain. When the pain signals are more intense compared to the not-pain signals, the inhibitory neurons are inactivated and the gate is opened. The T cells transmit the hurting signals to the spinothalamic tract that carries those signals to the brain. As a result, the neurological gate is influenced by the relative amount of activity in the large and the small nerve fibers.

Emotions and thoughts determine the style how pain is perceived

The theory besides proposed that the pain signal transmission can be influenced by emotions and thoughts. It is well known that people do not feel a chronic hurting or, to be more appropriate, the pain does non disturb them when they concentrate on other activities that involvement them. Whereas, people who are anxious or depressed experience intense pain and find it difficult to cope up with it. This is because the encephalon sends messages through descending fibers that stop, reduce or dilate the transmission of hurting signals through the gate, depending on the thoughts and emotions of a person.

Gate command theory in hurting management

The gate command theory has brought most a desperate revolution in the field of pain management. The theory suggested that pain management can be achieved by selectively influencing the larger nerve fibers that deport non-hurting stimuli. The theory has also paved mode for more inquiry on cognitive and behavioral approaches to reach pain relief.

I of the tremendous advances in pain management research is the advent of Transcutaneous Electrical Nerve Stimulation (TENS). The gate control theory forms the basis of TENS. In this technique, the selective stimulation of the large diameter nerve fibers carrying non-pain sensory stimuli from a specific region nullifies or reduces the effect of pain signals from the region. TENS is a non-invasive and inexpensive pain management arroyo that has been widely used for the handling of chronic and intractable hurting that are otherwise non-responsive to analgesics and surgical treatments. TENS is highly advantageous over pain medications in the aspect that information technology does non have the problem of drug interactions and toxicity.

Many other invasive and non-invasive electric stimulation techniques have been establish to exist useful in various chronic pain weather condition like arthritic pain, diabetic neuropathy, fibromyalgia, etc. The theory has as well been extensively studied in the treatment of chronic dorsum pain and cancer pain. However, favorable results are non attained in some conditions and the long term efficacy of the techniques based on the theory is under question.

Withal, the gate control theory has dramatically revolutionized the field of hurting enquiry and it has sown seeds for numerous studies that aim at presenting a pain-free lifestyle to the patients who suffer from chronic pain.

References

Abram SE (1993). 1992 Bonica Lecture. Advances in chronic pain management since gate control. Regional anesthesia, 18 (2), 66-81 PMID: 8098221

Bishop B (1980). Pain: its physiology and rationale for management. Function Three. Consequences of current concepts of pain mechanisms related to pain management. Physical therapy, 60 (1), 24-37 PMID: 6243184

Melzack R, & Wall PD (1965). Pain mechanisms: a new theory. Scientific discipline (New York, N.Y.), 150 (3699), 971-ix PMID: 5320816

Moayedi M, & Davis KD (2013). Theories of pain: from specificity to gate control. Journal of neurophysiology, 109 (one), 5-12 PMID: 23034364

Nizard J, Raoul S, Nguyen JP, & Lefaucheur JP (2012). Invasive stimulation therapies for the treatment of refractory pain. Discovery medicine, 14 (77), 237-46 PMID: 23114579

Nnoaham KE, & Kumbang J (2008). Transcutaneous electrical nerve stimulation (TENS) for chronic pain. The Cochrane database of systematic reviews (3) PMID: 18646088

Tashani O, & Johnson Thousand (2009). Transcutaneous Electric Nerve Stimulation (TENS) A Possible Aid for Hurting Relief in Developing Countries? The Libyan journal of medicine, 4 (ii), 62-5 PMID: 21483510

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What Is The Gate Control Theory? How Is It Similar To A Florida Intercoastal Drawbridge?,

Source: https://brainblogger.com/2014/06/23/gate-control-theory-and-pain-management/

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