New research provides evidence that training our heart rate can indirectly influence our emotional memory, making us more likely to remember positive experiences. The study has been published in the journal Applied Psychophysiology and Biofeedback.
The study aimed to explore whether certain brain circuits are responsible for regulating both heart rate and emotion, specifically focusing on the role of the ventromedial prefrontal cortex (vmPFC). Additionally, the researchers were interested in understanding how biofeedback training, which involves providing individuals with real-time physiological feedback and training them to modify their own physiological responses, could impact emotional memory biases.
“There have been many studies showing that people with higher resting HRV tend to experience less negative emotions,” study author Mara Mather told PsyPost. “But most of the research has been correlational and so it is not clear if the individual differences in HRV play any direct role in the emotional differences. Thus, we were interested in whether manipulating HRV could affect people’s emotional biases.”
To conduct the study, the researchers recruited 193 participants, including younger adults (ages 18-35) and older adults (ages 55-80). They excluded individuals with major medical, neurological, or psychiatric illnesses, those practicing meditation or specific breathing techniques, and those taking certain psychoactive drugs.
Participants were randomly assigned to either an HRV biofeedback group (Osc+) or a control group (Osc-) through the flip of a coin. The biofeedback training involved participants performing daily breathing exercises, aiming to either increase (Osc+) or decrease (Osc-) their heart rate oscillatory activity. They underwent a 7-week intervention, which included 5 weeks of biofeedback training using specialized software. The training involved following a visual pacer and adjusting their breathing pattern according to the feedback provided.
During the study, the participants completed an emotional memory task at Week 4 and Week 5. They viewed realistic photographs designed to induce positive, negative, or neutral emotional states. They then rated each image’s emotional valence and completed a free recall task, describing as many images as they could remember. In Week 5, they also underwent a recognition test for the images seen in Week 4, along with previously unseen images, using the Remember/Know paradigm to assess the vividness of memories.
The researchers found that participants in the Osc+ condition, who were trained to increase heart rate oscillatory activity, showed a memory bias favoring positive images over negative images compared to the Osc- condition. Additionally, the Osc+ condition was associated with increased left amygdala-mPFC resting-state functional connectivity. The mediation analysis suggested that changes in amygdala-mPFC functional connectivity mediated the relationship between the biofeedback condition and positive emotional memory bias.
The findings suggests that when people practice increasing their heart rate oscillations, it can help them regulate their emotions more effectively. This happens because the practice improves the coordination of certain brain circuits that are responsible for handling emotions, specifically the amygdala and medial prefrontal cortex.
“Heart rate variability biofeedback can influence people’s likelihood of remembering more of the positive or negative things they experienced,” Mather explained.
But the researchers noted that because they didn’t perform brain scans at every lab visit, they couldn’t determine how much of the effects they observed were due to short-term changes (during the lab visit) versus long-term changes (over several weeks) from the biofeedback training.
To better understand the influence of HRV biofeedback training, further research is needed to find out if the effects are immediate and short-lived or if they have a more lasting impact that can still be observed even if someone hasn’t practiced heart rate training in the past day or so.
The study, “Changes in Medial Prefrontal Cortex Mediate Effects of Heart Rate Variability Biofeedback on Positive Emotional Memory Biases“, was authored by Christine Cho, Hyun Joo Yoo, Jungwon Min, Kaoru Nashiro, Julian F. Thayer, Paul M. Lehrer, and Mara Mather.