Image Number 5 for United States Patent #4955388.
A method and apparatus for determining the level of attention of a subject to a visual stimulus such as a television commercial displayed on a screen (4) so as to provide objective information for designing the advertising presentation. The technique involves reflecting visible red radiation from arrays (16) of LEDs towards the eyes of the subjects (2) as a control signal at a predetermined frequency. The control signal is first applied to the subjects and EEG responses obtained. The control signal is then simultaneously applied with the display of the television commercial and EEG signals are again obtained. An assessment of the subjects interest is then made by determining the diminution in value of the components of the EEG response attributable to the control signal. A pair of illuminated goggles is also disclosed.