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When Pavel Goldstein's daughter was born, he noticed something in the delivery room. Holding his wife's hand seemed to ease her pain. He wanted to know whether that was real, and if so, how it worked.
So he took it into the lab. Goldstein, by then a postdoctoral pain researcher at the University of Colorado Boulder, published the study of 22 couples in PNAS in 2018. The women rated the heat about half as painful when their partners held their hands as when the men waited in the next room. Brain recordings added something more. While a couple held hands through the pain, their brainwaves fell into closer step, and in one set of connections between the two brains, the closer the match, the bigger the drop in the woman's pain ratings.
How the test worked
The couples, recruited through the University of Haifa in Israel, were aged 23 to 32 and in long-term relationships. Each partner wore a cap of electrodes recording electroencephalography (EEG), which picks up the brain's electrical activity through the scalp.
Only the women received pain. A small heated probe was pressed to the left forearm, set for each woman so it hurt at about 60 on a 0 to 100 scale. That took between 43.7°C and 48.5°C (about 111°F to 119°F). The men guessed, on paper, how much it hurt her.
The heat came in three two-minute tests, in an order that varied from couple to couple. In one he waited in the next room, in one he sat with her without touching, and in one he held her hand. The couples also went through the setups without heat. One of those, with the pair sitting out of each other's sight, later served as the baseline for the brain comparisons.
The women's average pain score was 52 with him in the next room, 38 with him sitting with her and 25 with him holding her hand. Hand-holding scored significantly lower than both.
What the brain recordings showed
The team looked at the alpha-mu band, brain rhythms between 8 and 12 cycles per second that earlier work had linked to pain and to empathy for someone else's pain. They measured how closely each partner's rhythms tracked the other's.
Some of that coupling turned up whenever the couple was together. It was strongest, with the largest network of links between the two brains, when he held her hand while she was in pain. Of the times they were together, it was weakest when she was in pain and he could not touch her. "It appears that pain totally interrupts this interpersonal synchronization between couples and touch brings it back," Goldstein said at the time, though the paper found some coupling remained.
The team had seen something similar in the body. In a companion paper on the same couples, the partners' breathing and heart rate fell into step more during the heat when he held her hand. When she was in pain and he could not touch her, no significant coupling showed up.
While he held her hand through the pain, one of three clusters of brainwave links tracked her relief: the stronger the coupling there, the bigger the drop in her pain. Another cluster tracked how well he guessed her score. Without touch, neither relationship showed up.
Where the evidence gets thinner
That link between coupling and relief is a correlation. The authors wrote that any causal link between the pain relief, the partner's empathy and the brain coupling "should be considered with caution." The coupling might have eased the pain, the easing might have let the rhythms fall into step, or something else might have driven both.
The sample was small. Twenty-two couples took part and two were dropped because the recordings failed. Only women received the heat and only men gave the touch, so the authors limited their conclusions to that direction. The study did not include same-sex couples, friends or strangers.
Brain synchrony itself is also debated. If it reflected shared thinking, it should rise when two people take in the same thing. In a 2024 perspective, Manuel Varlet and Tijl Grootswagers of Western Sydney University tested that by pairing up recordings of people who had each looked at pictures of objects on their own. Common synchrony measures barely changed whether the two had been shown the same object at the same moment or different ones. The authors suggested such synchrony "might be at best a poor proxy" for shared mental processing, though their test involved only pictures, not touch or pain.
False synchrony is a separate worry, and there Goldstein's team did take precautions. They compared each together condition with the no-heat baseline and used a measure chosen because it is less prone to spurious coupling. Neither step settles what the synchrony represents.
Does just being there help?
Pain scores were also lower with the partner simply sitting there. In the companion paper, the team described that gap as only marginal, short of statistical significance. Noting that brain coupling without touch did not track relief, the PNAS authors wrote that "the mere presence of the partner seems to be insufficient for pain reduction."
A 2020 study found presence did help, at least for women. A team led by Marianne Reddan tested 51 couples recruited in Boulder, Colorado, with heat on the leg. In 22 of the couples, the woman was the one who received it. For those women, a partner sitting quietly nearby, gently stroking the arm or holding the hand all lowered pain ratings compared with being alone. The three did not differ significantly, though hand-holding had the largest effect.
The men who received the heat reported no significant difference in pain with support. Skin conductance, a bodily measure of arousal, did fall with support in both sexes, mostly during hand-holding. The authors suggested men may play down pain in front of a partner or the researchers.
What a hand might be saying
Goldstein's team offered two possible explanations, neither of which the study directly tested. Touch may strengthen that coupling and let a partner's empathy reach the person in pain, so she feels understood, which could switch on the brain's reward system and so dampen pain. Or touch may blur the line between self and other, helping him feel her pain and pass on emotional support.
None of this was measured in a delivery room. In the experiment the heat lasted two minutes, and labor lasts hours. Whether a partner's hand does the same work through a night of contractions is a question these studies were not built to answer.
