---
title: "Opponent-Process Theory — AP Psychology Definition & Guide"
description: "Opponent-Process Theory explains color vision through three opposing pairs and is the AP Psych theory that finally cracks why afterimages happen."
canonical: "https://fiveable.me/ap-psych-revised/key-terms/opponent-process-theory"
type: "key-term"
subject: "AP Psychology"
---

# Opponent-Process Theory — AP Psychology Definition & Guide

## Definition

Opponent-Process Theory is a theory in psychology that suggests that our perception of color is based on three pairs of opponent colors: red versus green, blue versus yellow, and black versus white. According to this theory, when one color is perceived, its opposite color is suppressed.

## Review

### Related Terms

- [Color Blindness](/ap-psych-revised/key-terms/color-blindness): A condition where an individual has difficulty perceiving certain colors due to a deficiency or absence of specific cone cells in their eyes.
- Complementary Colors: Pairs of colors that are directly across from each other on the color wheel and create strong contrast when placed together.
- [Lateral Inhibition](/ap-psych-revised/key-terms/lateral-inhibition): The process by which neighboring photoreceptor cells inhibit each other's responses to visual stimuli, enhancing the contrast between different regions of visual input.