The Diderot effect refers to a situation in which the purchase of a new item or product leads to the purchase of additional items to match or complement the new product. The effect is named after the French writer and philosopher Denis Diderot, who first described the phenomenon in an essay.

In neuromarketing, the Diderot effect can be used to generate additional sales. By persuading customers to buy a new product, the demand for complementary products or services can be increased. An example of this would be a customer who buys a new smartphone and then also buys a matching protective case, charging station or headphones.

The Diderot effect can also help to strengthen customer loyalty and anchor the brand in the minds of consumers. When customers buy additional products that match their new product, they can feel that they have found a complete and coherent solution to their problem or need, which improves the overall brand experience.