The Mere Presence Effect

The Mere Presence Effect is a psychological phenomenon explaining that:

The mere presence of other people can change our performance,
even if they are not helping, speaking, or intentionally observing us.

Core Principle

When other people are present:

1. Physiological arousal increases.
2. The brain activates the dominant response.
3. Performance depends on how skilled we are at the task.

What Is a Dominant Response?

A dominant response is the behavior that is most automatic or well-learned for us.

• If the task is well-practiced / easy → performance improves.
• If the task is difficult / unfamiliar → performance worsens.

Performance Effects by Task Type

Real-Life Examples

🎮 Gaming

• A game you play often → You may perform better when someone is watching.
• A new game → You may make more mistakes.

🏃 Sports

• Trained athletes → Often perform better in front of an audience.
• Beginners → May become nervous and perform worse.

🧑‍💻 Work

• Routine tasks → Productivity may increase.
• Analytical or creative tasks → Thinking may become harder.

Difference from Evaluation Apprehension

Classic Research

Robert Zajonc (1965) conducted experiments showing that:

• On easy tasks, subjects performed better when others were present.
• On difficult tasks, performance declined in the presence of others.

Even animals (e.g., cockroaches) showed this pattern.

Short Summary

Others = Increase arousal
Skill level = Determines outcome

If the task is well-learned → Performance improves.
If the task is difficult or new → Performance decreases.