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Children with chronic stress-induced recurrent muscle pain have enhanced startle reaction
G Alfvén1, S Grillner2, E Andersson2,3
1Clintec, Karolinska Institute, Stockholm, Sweden.
Insights
Children with recurrent psychosomatic pain exhibit heightened muscle activity and startle responses. This study reveals a link between chronic stress, pain patterns, and amplified physiological reactions in adolescents.
Area of Science:
- Neuroscience
- Psychosomatic Medicine
- Pediatric Pain Research
Background:
- Recurrent pain in children linked to chronic stress often presents with specific tender points.
- The role of the startle reaction in these pain patterns requires further investigation.
Purpose of the Study:
- To test if the startle reaction is activated in children with recurrent psychosomatic pain.
- To determine if muscles involved in the tender point pattern show altered startle responses.
Main Methods:
- Electromyography (EMG) measured resting activity and acoustic startle responses.
- 19 children with psychosomatic pain (PAIN) and 23 controls (CON) aged 10-17 years participated.
- EMG analyzed muscles associated with tender points and lumbar erector spinae.
Main Results:
- The PAIN group displayed significantly higher resting muscle activity and startle responses compared to controls.
- Elevated EMG amplitudes, longer burst durations, and shorter burst latencies were observed in the PAIN group.
- These differences were consistent across multiple muscles and measures.
Conclusions:
- This research provides the first evidence of increased resting activity and potentiated startle responses in children with recurrent psychosomatic pain.
- Findings highlight the connection between chronic stress, pain, and heightened muscular tension in affected adolescents.
Background:
Children with recurrent pain of negative chronic stress origin from different locations have a characteristic pattern of tender points in the temporal, trapezoid, great pectoral and abdominal muscles. We tested the hypothesis that the startle reaction is activated in these children and that some of the startle-activated muscles are related to the tender point pattern and the recurrent pain.
Methods:
In children/adolescents, aged 10-17 years, 19 with recurrent psychosomatic pain (PAIN) and 23 controls (CON) we measured and analysed resting activity and acoustic startle response with electromyography (EMG) for the muscles involved in the pattern of tender points and also the lumbar erector spinae.
Results:
The PAIN group showed higher resting activity and higher acoustic startle response values than the CON group for all six muscles together regarding the mean amplitude in the initial 200 ms, and during the burst of activity, and longer burst duration and shorter burst latency. For PAIN versus CON, all separate muscles showed generally higher values of EMG amplitudes and burst durations, and shorter latencies for the burst onset in all measures; with significance or strong trends for several parameters and muscles.
Conclusion:
For the first time in children with recurrent psychosomatic pain, increased resting activity and potentiated startle response were demonstrated in the muscles involved in the stress tender point pattern.
Significance:
This study demonstrates in adolescents how recurrent pain of negative stress origin from the head, stomach, back and chest is related to increased startle reaction and increased muscular tension in these regions. This study contributes to the understanding of the mechanisms underlying the global burden of recurrent pain.
