Classroom Stress Contagion and HRV in Peers

ISEF Category: Behavioral and Social Sciences

Subcategory: Social Psychology  ·  Difficulty: Intermediate  ·  Setup: School Lab  ·  Time: 1 to 2 Months

The Hook

A single shaky presentation can change the energy in a whole room. Heart rate variability, or HRV, is one way to track that stress response in real time. This project asks whether nearby seated peers show the same drop when one student speaks.

What Is It?

Heart rate variability is the pattern of small time gaps between heartbeats. When stress rises, those gaps often get less varied. Think of it like traffic, smooth flow has lots of tiny changes, while tense, locked-in driving follows a tighter pattern.

This project looks at social contagion, the idea that emotion and arousal can spread from one person to others. If one student is visibly stressed during a presentation, nearby classmates may also show a shift in HRV, even if they are not the speaker. That makes the project a mix of social psychology and physiology.

Why This Is a Good Topic

This is a strong science fair topic because you can measure a real human response, compare nearby and farther peers, and test whether the effect changes with seat distance, familiarity, or presentation order. It connects to classroom climate, public speaking stress, and group dynamics. A student can learn study design, sensor logging, and basic statistical analysis without needing a university lab.

Research Questions

• How does seat distance from the presenter change the size of the HRV drop in nearby peers?
• What is the effect of speaker stress level, measured by self-report or baseline HRV, on peer HRV change?
• Does the HRV response differ between students who know the speaker and students who do not?
• To what extent does a live presentation trigger a larger HRV drop than a practice presentation?
• Which part of the presentation, the opening, question period, or close, aligns with the biggest peer HRV shift?
• How does the number of visible stress cues from the speaker relate to peer HRV change?

Basic Materials

• Polar H10 chest straps or an equivalent ECG-grade wearable for the speaker and nearby peers.
• Smartphone or tablet with Polar Beat or Polar Flow installed.
• Laptop for exporting and organizing HRV data.
• Quiet classroom or meeting room with fixed seating.
• Printed seating map and participant ID labels.
• Consent and assent forms approved by your school.
• Stopwatch or phone timer.

Advanced Materials

• Multi-channel ECG system with synchronized timestamps.
• External microphone or audio recorder for presentation timing.
• Video camera for posture and gesture coding.
• Calibrated room sound meter.
• Laptop with data-processing software for mixed-effects modeling.
• ECG adhesive electrodes and lead wires.

Software & Tools

• Python: Cleans HRV exports, aligns them to presentation events, and runs basic stats.
• Jupyter Notebook: Keeps code, notes, and plots in one place.
• R: Fits repeated-measures and mixed-effects models for peer comparisons.
• Google Sheets: Tracks seating order, session notes, and participant labels.
• Polar Flow: Exports session data from Polar H10 recordings.

Experiment Steps

1. Define your exposure groups, such as nearby peers, far peers, and a no-presentation control session.
2. Decide which HRV metric you will compare, and how you will align it to the presentation timeline.
3. Build a seating plan and labeling system that keeps each participant's position and session order consistent.
4. Plan controls that separate speaker stress from room-wide effects, such as baseline recordings and matched non-speaking sessions.
5. Choose your analysis plan before you collect data, including how you will compare changes across distance, order, and familiarity.

Common Pitfalls

• Mixing up motion noise with stress changes, which can distort Polar H10 readings when students shift in their seats.
• Letting the room setup change between sessions, which makes distance effects impossible to compare.
• Comparing raw HRV values instead of change from each student's baseline, which hides individual differences.
• Measuring only the speaker and no control peers, which makes normal room tension look like contagion.
• Stopping data collection at the loudest moment only, which misses delayed HRV shifts after the presentation starts.

What Makes This Competitive

A stronger version would separate true social contagion from shared context by adding matched control sessions, distance bands, and a clear baseline window. You could also test whether peer familiarity, speaker confidence, or audience size changes the size of the HRV shift. The strongest entries use mixed-effects models, pre-registered decisions about exclusion, and a clear effect-size story instead of only a p-value.

Project Variations

• Compare HRV changes during a live presentation versus a recorded video of the same speech.
• Test whether classmates seated in the front row show a larger HRV shift than students seated at the back.
• Compare peer HRV responses when the presenter is a friend, a stranger, or a teacher.

Learn More

• PubMed: Search for review articles on heart rate variability, stress, and social contagion.
• PubMed Central: Read full-text papers on psychophysiology and classroom stress without a paywall.
• Society for Psychophysiological Research: Find background pages and conference abstracts on HRV measurement and emotion.
• MIT OpenCourseWare: Search statistics and research methods lectures for repeated-measures design and hypothesis testing.
• Google Scholar: Search recent studies on emotional contagion, audience stress, and autonomic synchrony.