Chewing Gum and Stroop Interference

ISEF Category: Behavioral and Social Sciences

Subcategory: Behavioral Neuroscience  ·  Difficulty: Intermediate  ·  Setup: Home Setup  ·  Time: 1 to 2 Months

The Hook

A tiny habit like chewing gum can change how your brain handles conflict. That matters because attention is not just about focus, it is about choosing the right response while ignoring the wrong one. In this project, you can test whether mint, cinnamon, or unflavored gum changes that control in a measurable way.

What Is It?

The Stroop task is a classic attention test. You name the ink color of a word, even when the word itself spells a different color. Your brain has to ignore the fast, automatic reading response and pick the slower color-naming response instead. That slowdown is called Stroop interference.

Chewing gum may change alertness, arousal, or jaw movement, and those changes could affect how well you handle interference. Think of it like giving your brain a small background signal. The question is whether the signal helps, hurts, or does nothing, and whether flavor changes that pattern.

Why This Is a Good Topic

This is a strong science fair topic because the effect is easy to measure, the setup is low-cost, and the design can be tightened with preregistration and planned statistics. It connects to attention, executive control, and everyday behaviors like studying or test taking. You can learn how to design controls, reduce bias, and compare groups with real data instead of guesswork.

Research Questions

• How does mint gum affect Stroop interference compared with no gum?
• How does cinnamon gum affect Stroop interference compared with no gum?
• Does unflavored gum change reaction time on congruent and incongruent trials?
• To what extent does gum flavor change accuracy on the Stroop task?
• Which gum condition produces the largest difference between congruent and incongruent trial times?
• How does chewing gum affect the size of the Stroop effect within the same participant?

Basic Materials

• Computer or tablet with a keyboard.
• Online Stroop task builder or slide deck with color-word trials.
• Three gum conditions, mint, cinnamon, and unflavored.
• Timer or task software that records response time.
• Consent form and data sheet.
• Quiet room with consistent lighting and seating.
• Spreadsheet software for logging trial-level results.
• Headphones or a white-noise option if you need to reduce distraction.

Advanced Materials

• Response box or keyboard with precise timing logs.
• Open-source experiment software such as PsychoPy.
• Bayesian analysis software such as JASP or R with BayesFactor.
• Randomization script for participant condition order.
• Screen-based color calibration tool.
• Data-cleaning script in Python or R.
• Printer or device for standardized Stroop stimuli.
• Optional eye-level monitor setup to keep viewing conditions stable.

Software & Tools

• PsychoPy: Builds computerized Stroop tasks and records reaction times.
• JASP: Runs Bayesian tests and helps compare gum conditions.
• R: Cleans trial data and graphs interference scores.
• Python: Automates randomization, scoring, and participant order.
• Google Sheets: Tracks participants, conditions, and raw results.

Experiment Steps

1. Define the exact outcome you will measure, such as Stroop interference score or reaction time difference.
2. Choose one gum factor to test first, then lock the condition order and exclusions before collecting data.
3. Build a task version that keeps the words, colors, and trial counts the same across participants.
4. Plan controls for chewing time, hunger, caffeine, and time of day so they do not blur the result.
5. Pre-register the analysis plan, including how you will handle missed trials and outliers.
6. Set up both frequentist and Bayesian summaries so you can compare the size and certainty of the effect.

Common Pitfalls

• Letting participants choose their own gum, which confounds flavor with personal preference.
• Changing the order of conditions, which can create practice or fatigue effects.
• Using a Stroop task with too few trials, which makes reaction-time noise look like a real result.
• Mixing different screen settings or devices, which changes color appearance and slows responses for reasons unrelated to gum.
• Ignoring baseline differences between participants, which can hide or fake a gum effect.

What Makes This Competitive

A competitive version of this project would treat the question like a real study, not a classroom demo. That means preregistered predictions, randomized condition order, careful exclusion rules, and Bayesian analysis that reports how strong the evidence is, not just whether p is below a cutoff. Strong projects also separate flavor effects from chewing effects and show that the result holds across multiple ways of scoring interference.

Project Variations

• Test whether gum changes Stroop interference in teens versus adults.
• Compare gum flavor effects on the Stroop task with a simple reaction-time task as a control.
• Analyze whether self-reported alertness explains any gum effect on interference.

Learn More

• NIH PubMed: Search for review articles on chewing gum, attention, and executive function.
• NCBI Bookshelf: Read free background chapters on cognition and behavioral testing.
• APA Dictionary of Psychology: Check clear definitions for Stroop interference and executive function.
• JASP documentation: Learn how to run Bayesian t tests and report Bayes factors.
• Open Science Framework: Find preregistration templates and examples for behavioral studies.