Is Positive Affect as a Trait Related to Higher Heart Rate Variability in a Stressful Situation?

Area of Science:

• Psychophysiology
• Cardiovascular Research
• Affective Science

Background:

• Research on positive affect (PA) and cardiovascular activity often overlooks heart rate variability (HRV).
• Trait PA may promote autonomic nervous system (ANS) homeostasis by modulating sympathetic (SNS) and parasympathetic (PNS) activity.
• Heart rate variability (HRV) serves as a key indicator of parasympathetic nervous system (PNS) function.

Purpose of the Study:

• To investigate the influence of trait positive affect (PA) on cardiovascular responses during stress.
• To examine the relationship between trait PA and heart rate variability (HRV) during cognitive and social stress tasks.

Main Methods:

• Monitored heart rate variability (HRV) via RMSSD, heart rate (HR), and interbeat interval (IBI) in 54 participants.
• Participants completed cognitive tasks (including fatigue-inducing Stroop tasks) and Trier Social Stress Tasks.
• Trait positive affect (PA) was assessed using the PANAS scale.

Main Results:

• Higher trait PA was associated with significantly greater HRV (RMSSD), indicating increased parasympathetic nervous system (PNS) activity.
• Individuals with high trait PA demonstrated lower heart rate (HR) and higher interbeat interval (IBI) during a fatiguing cognitive task.
• These effects were particularly pronounced during the fatigue-inducing phase of task performance.

Conclusions:

• Elevated trait positive affect (PA) is linked to enhanced heart rate variability (HRV) and a more balanced autonomic nervous system (ANS) response.
• Individuals with high trait PA exhibit more adaptive cardiovascular regulation and potentially better emotional regulation under prolonged stress.
• Findings underscore the role of trait PA in maintaining physiological homeostasis during demanding tasks.