Mendi is a Swedish company that makes a home neurofeedback headband. The device sits across the forehead and supports short sessions for attention and mental fitness. An app turns the response into visual games.

How it works
Functional near infrared spectroscopy uses infrared light to measure changes in oxygenated blood near the prefrontal cortex. Activity in this region can increase blood flow and oxygen use. During a session, the app converts the signal into feedback, encouraging the user to raise the displayed level over repeated practice.

Key considerations
Blood oxygen changes are an indirect measure of brain activity and do not reveal thoughts or prove cognitive improvement. Hair, movement, skin contact and ambient light may affect readings. Evidence for the finished consumer product remains limited, and benefits require training.