Is pain just a subjective feeling?

In the war movie, the warriors are seriously injured but can bravely step forward to kill the enemy.
The subjective feeling of pain seems to be greatly weakened.
On the contrary, in the psychiatric department, complaints of "affected limb pain" are frequent and can be relieved by psychotherapy.

Then, is there a correlation between this feeling of "pain" and subjective "consciousness"? What inspiration does this have for the treatment of "pain" encountered in the clinic? Author: Tsai This article is the author's permission NMT Medical publish, please do not reprint without authorization.

From a psychological perspective, some scholars say that "pain is a subjective consciousness produced by the brain, but sometimes it is just an illusion.
"
It seems that pain is like an illusion, a specious existence (see the video below).

Pain is a complex social-physiological-psychological phenomenon, which is related to a variety of neuroanatomy and neurotransmitter, and is the result of the interaction of a variety of cognitive and emotional processes.

The International Association for Pain Research defines pain as follows: "Pain is an unpleasant feeling and emotional experience associated with actual or potential tissue damage, or the description of this damage.
"
Therefore, pain has not only sensory and emotional components, but also an expected cognitive component of future harm.

This article focuses on explaining the relationship between pain and psychology.

Pain perception involves a large number of psychological processes, including attention to the perception and source of pain, cognitive assessment of sensory meaning, and subsequent emotional, psychophysiological, and behavioral responses (Figure 1).

 Figure 1 The perception of painful stimuli and the response process of the nervous system to it.
The psychological process of pain 1.
Painful attention refers to the tendency of selectively processing certain stimuli and ignoring other stimuli.
It is human perception (visual, auditory, taste, etc.
) ) And perception (consciousness, thinking, etc.
) at the same time to direct and focus the selection of certain objects (exclude other factors). The brain can perform information evaluation and processing on stimuli according to the body's specificity, so that the realization of desire stimuli or the avoidance of aversion stimuli can produce different emotional states, regulate and direct attention.

Therefore, the pain experience varies with the degree of attention-when the attention is focused on the pain, the subjective feeling of pain will be stronger; and when the attention is shifted from the pain, the pain will be weakened.

Attentional adjustment of pain experience is related to changes in painful nerve matrix activation.

The activation of pain-related parts in the somatosensory cortex, thalamus and insula will cause decreased attention, but it can cause increased excitability of the prefrontal cortex, anterior cingulate cortex, and midbrain aqueduct gray matter, indicating the attention adjustment of pain There is overlap and interaction between the brain system and the downward pain regulation system.

On the contrary, when the pain is paid more attention to, the intensity of the pain will increase, and the feeling of harmlessness will be interpreted as a sense of pain.

 2.
Cognitive assessment of pain Cognition refers to the process of people acquiring knowledge or applying knowledge, or the process of information processing.
This is the most basic human psychological process, including feeling, perception, memory, thinking, imagination and language.

When receiving harmful stimuli, individuals will consciously or unconsciously evaluate the content of the sensory signals sent by the body to determine the extent of actual or potential harm they may suffer.

The evaluation process is subjective and inherently variable.

The sensation of pain to the human body depends on the individual’s perception of the injury stimulus (copeability)-when the human body believes that the existing resources are sufficient to cope with the injury, then the pain is considered controllable, regardless of whether the individual takes pain control or not Way, the intensity of pain will be reduced.

The anterolateral prefrontal cortex is considered to be related to emotion regulation, and its activation is positively correlated with the degree of pain that is considered controllable, and negatively correlated with subjective pain intensity.

Current research has found that psychological intervention can reduce the severity of pain by increasing the harmless sensory information of pain perception.

3.
Painful emotions and psycho-physiological reactions.
Aversion to pain can cause strong emotional reactions, feedback and adjustment of pain perception, resulting in emotions of anger, sadness and fear. Emotions are related to autonomic nervous, endocrine and immune responses, and can aggravate pain through many psychophysiological pathways—pain increases sympathetic nerve excitability, causes anxiety, increased heart rate, etc.
, and enhances the body’s response to negative emotions, but after a long time response It also increases blood flow to the muscles and increases muscle tension, aggravating the original damage; negative emotions and pressure increase muscle tissue contraction, which may cause cramps; pain input from internal organs and muscles may excite the vagus nerve, leading to hypotension and bradycardia The responsiveness to the environment is reduced; in addition, the release of pro-inflammatory cytokines and cortisol can enhance nociception and promote the processing of aversive information in the brain.
When it occurs for a long time or repeatedly, it may cause or aggravate tissue damage.

Negative emotions are related to the increased activation of emotional processing and pain management structures such as the amygdala, anterior cingulate gyrus and anterior insula structure, which can promote the transfer of attention to pain, aggravate pain discomfort, and enhance the ability to perceive the human body ( Feeling of the physical condition of the body).

In addition, negative emotions and stress can impair the function of the prefrontal cortex, leading to a decline in advanced cognitive functions.

 4.
Pain behavioral response Pain is not only a sensory perception and emotional experience, but also involves behavioral responses that may reduce, aggravate, or prolong the experience of pain.

Human body related behaviors such as support, painful expressions, sighs, etc.
after pain may aggravate the feeling of pain, and at the same time have social impacts, and produce alternative benefits (compassion, tolerance, reduced expectations, social connections, etc.
) to individuals suffering from pain.

In addition, avoidance behavior can temporarily relieve pain, but long-term use of avoidance behavior can aggravate the poor prognosis of disability.

 Table 1 Summary of the psychological process of pain Pain and disability pain, especially chronic persistent pain, has a serious impact on physical and mental health and is one of the important factors affecting disability.

There are currently five mainstream theories about the relationship between pain and disability (Table 2).

Table 2 Pain and disability psychological model Pain management is essential for persistent, recurrent or chronic pain.

Patient-centered clinical management methods need to take into account individual differences among patients' lifestyles, professional needs, social support, health habits, personal coping skills, and other factors that may significantly affect the environment.

Table 3 summarizes the ten principles of psychological management of pain.

Table 3 Summary of ten principles of psychological management of pain This article summarizes the relationship between pain and mental activity.

In the process of clinical practice, simple and effective medications are often our first choice for pain patients.
However, for such patients, it is necessary to dig deeper into the psychological factors behind them and carry out related mental health management.
It is more important to reduce the harm of pain to the body and mind.  References: 1.
Pain is Weird.
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