How pain affects focus and attention

Here are three scientific articles about the effect of “pain” on brain functions, like focus and attention, proving that the “sensation of pain” we feel is a very “real” physiological state, not a psychological issue.

• Assessment of heart rate variability in the patients suffering with chronic pain of musculoskeletal origin
• Pain Affects Visual Orientation: an Eye-Tracking Study
• Does experimentally induced pain affect attention? A meta-analytical review

Pain Affects Visual Orientation: an Eye-Tracking Study – PubMed – Feb 2019

Because of its unique evolutionary relevance, it is understood that pain automatically attracts attention.

No, it certainly is *not* understood by most people and even doctors.

They think we can just “stop thinking about it” and that it bothers us so much only because we “worry” about it and “catastrophize”.

So far, such attentional bias has mainly been shown for pain-related stimuli whereas little is known about shifts in attentional focus after actual painful stimulation.

This is a distinction without a difference: painful stimulation IS a pain-related stimuli.

Perhaps they are referring to the difference between “attentional bias” and “shifts in attentional focus”, which also sound like they describe the same thing.

This study investigated attentional shifts by assessing eye movements into the direction of painful stimulation.

Healthy participants were presented either a blank screen or a picture showing a natural scene while painful electrical stimuli were applied to the left or right hand.

In general, painful stimulation reduced exploratory behavior as reflected by less and slower saccades as well as fewer and longer fixations.

• Painful stimulation on the right hand induced a rightward bias (ie, increased initial saccades, total number and duration of fixations to the right hemifield of the screen).
• Pain applied to the left hand as well as no pain induced a leftward bias that was largest for the direction of first saccades.

These findings are in line with previous observations of attentional biases toward pain-related information and highlight eye tracking as a valuable tool to assess involuntary attentional consequences of pain.

This attention-capturing quality of pain should be examined in chronic pain conditions because it might contribute to the cognitive impairments often observed in chronic pain patients.

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Assessment of heart rate variability in the patients suffering with chronic pain of musculoskeletal origin – National Journal of Physiology, Pharmacy and Pharmacology – 2017

Background:

Prolonged pain of musculoskeletal origin can cause changes in autonomic outflow and thereby cardiovascular system.

Various studies have been conducted showing the effect of chronic pain on heart rate variability (HRV), but the same study has not been conducted in the population of Eastern Uttar Pradesh.

Materials and Methods:

The patients were selected from the pain clinic out patient department with chronicity of >6 months duration and severity of >3 on visual analog scale. Age-sex matched controls were also selected.

Electrocardiogram was recorded in the resting state and was analyzed for the HRV by using time and frequency domains.

Results:

In male cases, maximum RR interval, minimum RR interval, mean RR interval and in female cases, minimum RR is significantly different than male and female controls, respectively (P < 0.05).

In frequency domain, low frequency/high frequency (L.F./H.F) ratio in male cases and L.F.m2 in female cases are different than male and female controls, respectively.

Conclusion:

The observations reveal that there is a decrease in parasympathetic activity and an increase in the sympathetic activity in the cases as compared to their age-sex matched controls leading to the shifting of sympathovagal balance toward the sympathetic side.

The pattern of changes is similar, both in male cases versus male controls and female cases versus female controls with little difference in the magnitude.

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Does experimentally induced pain affect attention? A meta-analytical review – Free full-text /PMC6368116/ – J Pain Res. 2019

Background

Recent studies have found that clinical pain is related to cognitive impairment.

However, there remains a scarcity of systematic reviews on the influence of acute pain on attention.

Laboratory-induced pain is often used to simulate acute pain.

The current systematic meta-analysis aimed to evaluate the effect of induced-pain on three components of attention (orienting, alerting, and executive attention) in healthy subjects.

Methods

A systematic search of three databases was performed. Only data from studies that administered laboratory-induced pain and that also included a control group were selected. The effects of experimental pain on orienting attention, alerting attention, and executive attention were analyzed.

Results

• Performance on alerting attention was decreased by pain.
• Executive attention was not significantly affected by pain.

I believe this is entirely due to the difference between acute, experimentally-induced pain and general chronic pain.

While a sharp jab would momentarily distract us (attention), our brain would instantly try to figure out what caused it and how to stop it (executive function), which is the normal purpose of pain.

Constant pain is something entirely different: its relentless chronicity, day after day after week after month after years and decades is wearing, exhausting, and often overwhelming.

It should be obvious that such persistent abnormal brain activity would have consequences on the healthy functioning of this organ.

Conclusion

There was moderate evidence that experimentally induced pain can produce effects on orienting and alerting attention but not on executive attention.

This meta-analysis suggests that experimentally induced pain influences some aspects of attention.