Research reveals how brain's opioids modulate responses towards other people's pain

May 30, 2017, University of Turku
Credit: CC0 Public Domain

Recent results obtained by researchers from Turku PET Centre and Aalto University have revealed how the human brain's opioid system modulates responses to other people's pain.

Seeing others experiencing activated brain circuits that are known to support actual first-hand experience of pain. The fewer receptors in the participants' brains, the stronger were their emotion and pain circuits' response to seeing others in distress. Similar association was not found for the dopamine system despite its known importance in pain management.

"Capacity for vicarious experiences is a fundamental aspect of human social behaviour. Our results demonstrate the importance of the endogenous opioid system in helping us to relate with others' feelings. Interindividual differences in the opioid system could explain why some individuals react more strongly than others to someone else's distress," says Researcher Tomi Karjalainen from Turku PET Centre.

"The results show that first-hand and vicarious pain experiences are supported by the same neurotransmitter system. This finding could explain why seeing others in pain often feels unpleasant. High opioid-receptor availability may, however, protect against excessive distress resulting from negative social signals, such as other people's . Our findings thus suggest that the brain's opioid system could constitute an important social resiliency factor," says Professor Lauri Nummenmaa from Turku PET Centre and Department of Psychology at the University of Turku.

The study was conducted by using (PET) and imaging (fMRI). The participants were injected with radioactive compounds that bind to their brain's opioid and dopamine receptors. Radioactivity in the brain was measured twice with the PET camera to map the distribution of opioid and dopamine receptors. Subsequently, the participants' activity was measured with fMRI while they viewed videos depicting humans in various painful and painless situations.

The findings were published on May 24 2017 in the scientific journal Cerebral Cortex.

Explore further: Obesity associated with brain's neurotransmitters

More information: Tomi Karjalainen et al. Dissociable Roles of Cerebral μ-Opioid and Type 2 Dopamine Receptors in Vicarious Pain: A Combined PET–fMRI Study, Cerebral Cortex (2017). DOI: 10.1093/cercor/bhx129

Related Stories

Obesity associated with brain's neurotransmitters

March 4, 2015
Researchers at Aalto University and University of Turku have revealed how obesity is associated with altered opioid neurotransmission in the brain.

Obesity surgery normalizes brain opioids

October 13, 2015
Researchers at Aalto University and University of Turku have revealed how obesity surgery recovers opioid neurotransmission in the brain.

How fear can develop out of others' traumas

May 25, 2017
What happens in the brain when we see other people experiencing a trauma or being subjected to pain? Well, the same regions that are involved when we feel pain ourselves are also activated when we observe other people who ...

Opioids produce analgesia via immune cells

January 17, 2017
Opioids are the most powerful painkillers. Researchers at the Charité - Universitätsmedizin Berlin have now found that the analgesic effects of opioids are not exclusively mediated by opioid receptors in the brain, but ...

New type of opioid targets pain areas directly avoiding negative side effects

March 3, 2017
(Medical Xpress)—A team of researchers with the Free University of Berlin and Zuse-Institut Berlin has developed a type of opioid that was shown to target pain in rats without causing negative side effects. In their paper ...

Study examines polyneuropathy and long-term opioid use

May 22, 2017
Polyneuropathy is a common painful condition, especially among older patients, which can result in functional impairment.

Recommended for you

How do we lose memory? A STEP at a time, researchers say

March 23, 2018
In mice, rats, monkeys, and people, aging can take its toll on cognitive function. A new study by researchers at Yale and Université de Montréal reveal there is a common denominator to the decline in all of these species—an ...

Brain's tiniest blood vessels trigger spinal motor neurons to develop

March 23, 2018
A new study has revealed that the human brain's tiniest blood vessels can activate genes known to trigger spinal motor neurons, prompting the neurons to grow during early development. The findings could provide insights into ...

Being hungry shuts off perception of chronic pain

March 22, 2018
Pain can be valuable. Without it, we might let our hand linger on a hot stove, for example. But longer-lasting pain, such as the inflammatory pain that can arise after injury, can be debilitating and costly, preventing us ...

From signal propagation to consciousness: New findings point to a potential connection

March 22, 2018
Researchers at New York University have discovered a novel mechanism through which information can be effectively transmitted across many areas in the brain—a finding that offers a potentially new way of understanding how ...

Using simplicity for complexity—new research sheds light on the perception of motion

March 22, 2018
A team of biologists has deciphered how neurons used in the perception of motion form in the brain of a fly —a finding that illustrates how complex neuronal circuits are constructed from simple developmental rules.

Focus on early stage of illness may be key to treating ALS, study suggests

March 22, 2018
A new kind of genetically engineered mouse and an innovation in how to monitor those mice during research have shed new light on the early development of an inherited form of amyotrophic lateral sclerosis (ALS).


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.