Abstract: A method of detecting and classifying mental states, comprising the steps of: detecting bio-signals from one or more than one bio-signal detector; transforming the bio-signals into one or more than one different representations; detecting values of one or more than one property of the transformed bio-signal representations; and applying one or more than one mental state detection algorithm to the detected properties in order to classify whether the bio-signals indicate the presence of a predetermined response by a subject.

Abstract: A method of assisting a user in bringing a plurality of EEG electrodes into proper contact with the user's scalp includes receiving a signals from EEG electrodes, determining a state of contact with the user's scalp, and displaying a representation of the user's scalp and an indicator of the state of contact, the indicator positioned on the representation in a position representative of a position of an associated electrode on the user's scalp. Determining quality of contact of an electrode on a user can includes applying a reference signal to a user, receiving a measured signal from an electrode for monitoring bioelectric signals of the user, and determining a state of contact of the electrode with the user based on the measured signal and the reference signal.

Abstract: An operational amplifier circuit is described. The operational amplifier circuit includes an operational amplifier, a high-pass filter portion, and a feedback loop, wherein the operational amplifier circuit is configured to output an amplified filtered version of a bio-signal. The operational amplifier includes a non-inverting input terminal, and an inverting input terminal, wherein the inverting input terminal and the non-inverting input terminal are configured to be coupled to a common reference potential through resistors. The high-pass filter portion is configured to receive a bio-signal as input and to provide input to the non-inverting input terminal of the operational amplifier. The feedback loop includes a low-pass filter portion, wherein the low-pass filter portion is configured to receive input from an output of the operational amplifier and to provide input to the inverting input terminal of the operational amplifier.

Abstract: An electrode is described. The electrode includes an electrode plate and a sensor circuit electrically connected to the electrode plate. The electrode can include a gimbaled contact element and a conductive flexure element connecting the electrode plate and the gimbaled contact element and providing a conductive path therebetween. In another implementation, the electrode can include a contact element having an upper surface in contact with the electrode plate and a lower surface configured to contact a subject's skin. The contact element is adapted to contain a conductive fluid and provide a conductive path from the subject's skin to the sensor circuit by way of the electrode plate therebetween.

Abstract: An electrode headset and electrodes that can be mounted therein are described. The electrode headset can be formed from substantially rigid components including some flexibility to snugly embrace a variety of head shapes and sizes, while providing reliable positioning of electrodes according to an electrode placement scheme on a subject's head. Alternatively, the electrode headset can be formed from soft and stretchable bands with voids formed therebetween.

Abstract: An electrode headset in which electrodes can be mounted is described. The electrode headset can be formed from substantially rigid components including some flexibility to snugly embrace a variety of head shapes and sizes, while providing reliable positioning of electrodes according to an electrode placement scheme on a subject's head. In another implementation, the electrode headset can be formed from soft and stretchable bands with voids created therebetween.

Abstract: A method of detecting and classifying facial muscle movements, comprising the steps of: receiving bio-signals from at least one bio-signal detector; and applying at least one facial muscle movement-detection algorithm to a portion of the bio-signals affected by a predefined type of facial muscle movement in order to detect facial muscle movements of that predefined type.

Abstract: A method of detecting a mental state includes receiving, in a processor, bio-signals of a subject from one or more bio-signal detectors, and determining in the processor whether the bio-signals represent the presence of a particular mental state in the subject. A method of using the detected mental state includes receiving, in a processor, a signal representing whether a mental state is present in the subject. The mental state can be a non-deliberative mental state, such as an emotion, preference or sensation. A processor can configured perform the methods, and a computer program product, tangibly stored on machine readable medium can have instructions operable to cause a processor to perform the methods.

Abstract: A method of detecting and classifying mental states, comprising the steps of receiving bio-signals from one or more bio-signal detectors; generating multiple different representations of each bio-signal; determining the value of one or more features of the each bio-signal representation; and comparing the feature values to one or more than one mental state signature, each mental state signature defining reference feature values indicative of a predetermined mental state.

Abstract: A method of detecting and classifying mental states, comprising the steps of: detecting bio-signals from one or more than one bio-signal detector; transforming the bio-signals into one or more than one different representations; detecting values of one or more than one property of the transformed bio-signal representations; and applying one or more than one mental state detection algorithm to the detected properties in order to classify whether the bio-signals indicate the presence of a predetermined response by a subject.

Abstract: A method of detecting and classifying facial muscle movements, comprising the steps of: detecting bio-signals from a plurality of scalp electrodes; and applying one or more than one facial muscle movement-detection algorithm to a portion of the bio-signals affected by a predefined type of facial muscle movement in order to detect facial muscle movements of that predefined type.