Brain activity estimation device

A brain activity estimation device comprising:

• a facial skin temperature acquisition element arranged and configured to detect a skin temperature of at least part of a human face, and to acquire facial skin temperature data including detected temperature data and location data of a detection region thereof in a time series manner;
• and
• a brain activity estimation element arranged and configured to estimate human brain activity based on the facial skin temperature data acquired by the facial skin temperature acquisition element,
• the brain activity estimation element being further arranged and configured to
• decompose the facial skin temperature data into a plurality of components by singular value decomposition, principal component analysis, or independent component analysis,
• extract a component as a determination component from among the plurality of components, the component having an amplitude of a component waveform thereof that is correlated to changes at a time when a brain is at rest and a time when a brain is stimulated, and
• determine whether the determination component is related to the human brain activity based on a presence or absence of a temperature change in a prescribed region of the human face.