Is Pain Physical, Mental, or Both?
Pain is uncomfortable sensory and emotional experience associated with real or potential tissue damage or described in terms of such damage which is caused by both physical and mental factors. This phenomenon is familiar to everyone. In human perceptions, pain and diseases are related very closely. There is hardly a person who did not repeatedly experience the feeling of pain throughout life. However, familiar to everyone, sensation of pain is an extremely complicated issue. Although this concept has a definite meaning in the physiological processes of the body, pain is one of the central problems in neuroscience. However, there is not even a single generally accepted definition of this phenomenon, revealing its essence. At the same time, in light of a significant number of studies on the issue, pain has complicated nature. Pain is both physical and mental based on the fact that it has both a physically adjusted way of perception as well as mental features affecting it.
Arguments in Favor of Physical Nature of Pain
Functions of Pain
When examining the nature of pain, one can assume that it has completely physical nature designed in order to protect the organism. Pain is formed as a response of the body on the stimuli which damage it. Formation of the feeling of pain is an adaptive feature that promotes the survival and has developed in the process of evolution of living beings. Pain excitement is primarily a signal value, a warning about the violation of two vital constants of the body: the integrity of the protective coating membranes that provides a constant internal environment, and a certain processes in tissue that ensure normal functioning of the body.
From a neurobiological perspective, pain can be examined in three different directions. First, pain can be regarded as a warning signal of defense system which is aimed at detecting and ceasing or stopping the contact with harmful or damaging stimuli. Secondly, pain also has adaptive and protective features. The protective properties of pain as a signal of danger can manifest itself only when it occurs in response to a stimulus of malicious irritations. Apparently, for this reason, in the course of evolution, a certain biological feasibility of pain threshold has been developed and genetically designated leading to the occurrence of pain in response to harmful stimuli only. Thirdly, pain is maladaptive due to being a result of abnormal functioning of the nervous system (Woolf & Clifford, 2015).
How Pain Works Neurologically
In the physiological sense, pain is understood as a response of the body to the impact of any adverse external stimulus. Additionally, pain can be a consequence of an illness of the body and have an isolated character, regardless of the condition of the body. Pain is caused by physical, chemical and biological factors. Neurologically, the mechanism of pain is adjusted perfectly through a complicated set of reactions of the body on the external and internal stimulus. Thus, considering pain from the neurological perspective allows concluding that it has only physical nature.
There are two main types of pain: nociceptive and neuropathic. Their difference is due to the sources. Nociceptive pain is a result of receptor’s activation of the peripheral nervous system, pain stimulus, due to tissue damage. Neuropathic pain is based on damage or dysfunction of the central nervous system or peripheral nerves. Tissues are innervated by the sensory nerve fibers. The fibers react selectively to irritations because of their intensity and potential harm. The nerves spread messages in the central nervous system. These messages include multiple branch circuits in the central nervous system, which produce a variety of objective and subjective responses. Damaged tissue activates sensory-afferent primary fibers which, in term, provide information to the spinal cord. Primary treatment occurs at the level of the posterior horn, and then, in the spinothalamic tract of the thalamus. The path diverges into the medial projections on the anterior lobe, which includes anterior cingulate gyrus, a lateral path that extends in somatosensory cortex. Signals depend on contextual clues and memories that arise from the frontal cortex and amygdala and the project in the midbrain periaqueductal gray, which controls the way through the spinothalamic rostral ventromedial cortex (Fields & Howard, 2007).
Arguments in Favor of Mental Nature of Pain
Role of the Brain in the Perception of Pain
Considering the aforementioned factors, the supposition that pain has only physical nature seems reasonable. However, pain has many subjective psychological factors despite pure physiology. Interestingly, the brain itself is devoid of nociceptive tissue and, therefore, cannot feel pain. When pain impulses originate in nerve endings and reach the higher brain centers, they are treated in the same way as other forms of information, namely, sensory impulses from distant nerve terminals are integrated with memories, expectations, emotions, and thoughts that ensures the completeness of perception. Holistic perception of pain depends on the emotional state and thinking process coordinated by the pain signals from the lesion.
A key role in perception of pain belongs to structures of the brain, which is a complex system that analyzes and modifies the pain impulses. The brain works symbolically. Objects and events encoded in neural activity are not limited to space and time. Due to the activity of the brain, one can imagine the events he or she experienced in the past or will experience in the expected future. Addressing the subjective experience of pain with the brain, one can highlight three separate components. Firstly, there is a pure discriminatory part, which includes recognition of the quality of feeling and its localization. All three components of the subjective experience of pain are a triggered activity in peripheral nerves that enter the spinal cord and activate cells that act on the opposite thalamus. The process happens in spinothalamic tract, which is mandatory for all components of the sensation of pain in normal people. At the level of the thalamus, the pain signal diverges into separate paths that are different components of experience. Discriminatory component largely comprises somatosensory cortex. In contrast, in the forebrain region known as the limbic system, motivational and emotional component of pain mediates. The limbic system includes the cingulate gyrus and prefrontal cortex of the island and subcortical structure known as the amygdala (Fields & Howard, 2007).
Symbolic Nature of Brain Operations
Due to above-mentioned processes, it can be concluded that symbolic nature of all brain operations can influence the processes in the body and their perception as experienced by an individual. Thus, symbolic representation affects the experience of pain, to a great extent.
The role of the brain in perception of pain is not limited only to physical processes. The smallest unit of the nervous system is a network, a set of interconnected neurons. Their coordinated activity reproduces the observed actions or subjective experience. The spatial and temporal pattern of activity of neurons in the network produces an effect (or perception) of representation. Neuroscientists say the presentation codes such phenomena as incentives or targeted traffic. Thus, representations are connected to events external to the brain (Fields & Howard, 2007).
The concept of representation depends on the character of what is represented. Although the presentation may not be associated with the outside world, even these representations are commonly understood in the context of items which are external to the brain. Our subjective experience of self, the body, and the world is an emergent property of dynamic networks coordinated by neural activity. The brain must contain a representation of the body itself (the mind) and the outside world. These ideas lead to an ongoing subjective experience of an individual (Fields & Howard, 2007).
Performances are the neural (physical) incarnation of sense, which is often understood in the context of intention. The main task of the brain is to make a choice between objectives, and this, in turn, depends on the values and predicting consequences. Thus, brain strongly affects the perception of pain. Giving an image of the damage and connecting it with the symbolical representation of possible suffering, brain determines, to a certain extent, the level of pain experienced by a person. Consequently, due to this symbolical nature of brain operations, pain is mental (Fields & Howard, 2007).
The Possibility of Treatment of Pain by Means of Music, Massages, and Exercises
Sound activates the sensory pathways which mute pain and help to reduce the pain threshold. Thus, the sensation of pain can be reduced with sound. The brain acts as a mechanism of blocking physical pain in the body. Feeling pain in humans can become lower when they hear the neutral sound. This is another proof that we can learn to use the mind to reduce pain (Gardner & Licklider, 2015).
Massage is one of the oldest methods of treatment which can take away the pain of a different nature. Quick and deep massage excites the sympathetic nervous system and relieves pain along the nerve bundles. In addition, exercises relieve stress and pain. Effect on the body is very comforting. Its meaning lies in massaging and stroking the relevant points on the body. Often massage for cancer can help to eliminate the pain at the early stages of disease. This method helps in treatment and prevention of cancer. Massage has been studied as a maintenance therapy for the relief of pain associated with cancer. Massage can help a patient to relax and improve one’s mood. Massage has a direct impact on the tissues of the body. Moreover, research shows that massage can be safe in patients with cancer (Cassileth & Vickers, 2015)
Moreover, recent studies have evidenced that physical activity helps reduce chronic pain. Physical activity should be combining with nonpharmacological treatments, and then can be used as means for overcoming pain or reducing its level. Patients engaged in physical activity claimed that pain became milder (Ambrose & Golightly, 2015).
When considering these facts, it can be noted that massage, sound, exercises definitely are not able to fix damaged tissue or eliminate the source of pain. At the same time, these actions would not be able to influence pain if it has been purely physical. All these facts are evidence that pain has mental nature as well.
Pain has both physical and mental nature. Trying to clarify whether there are specific pain receptors and pain is a result of stimulation of different receptors when certain stimulus is intense, one can assume that, probably, pain receptors as such do not exist. Various nerve endings are specific for each event of information exposure. According to the received information, the nervous system assesses the level of irritation and implementing responses of the body. When the level exceeds a certain threshold and requires increased work on the nervous system, pain occurs. Thus, pain seems to be a stereotypical reaction in the body when there is excessive level of stimulation of all types of receptors. The intensity of pain depends on the specifics of the stimulated analyzer and tension level. At the present time, the view can be considered generally accepted that the pain is an important biological factor generated by nature as the bodyguard.