The buy button (also known as a "call-to-action") refers to a specific request to the consumer to perform a certain action, such as making a purchase or signing up for a newsletter. In online marketing, the buy button is often presented as an eye-catching button that leads the consumer directly to the desired action.

The buy button is of great importance for neuromarketing, as it can influence consumers' purchasing decisions. A well-placed and appealing call to action can direct the consumer's attention to the desired goal and prompt them to take an action they might not otherwise have taken. Therefore, it is important to strategically place the buy button and make it appealing in order to increase engagement and conversion rates.

There are various techniques used in neuromarketing to optimise the buy button, such as the use of colours and fonts, placing the buy button in a highly visible location or using emotionally appealing language that encourages the consumer to take an action. By optimising the buy button, a company can increase the conversion rate and boost sales.