Thought Technology Ltd. Procomp Infiniti, Руководство по оборудованию

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Sensors
GENERAL SENSOR FACTS
Thought Technology sensors are completely non-invasive and require little or no skin preparation
when used for feedback purposes. They include sensors specialized for electromyography (EMG),
electroencephalography (EEG), electrocardiography (EKG), blood volume pulse (BVP), skin
conductance (SC), respiration and temperature.
Sensor Anatomy
The EMG, EKG and EEG sensors have a positive, a
negative and a ground electrode. The signal is measured
between the positive and negative. The ground acts as a
reference point, and is used for filtering out electrical
"noise" that is picked up from all three electrodes.
Contact With The Client's Skin
Because some biofeedback sensors are applied directly to the skin or scalp, some consideration
must be given to using proper hygienic controls. Whenever possible, we recommend the use of
disposable electrodes. The electrodes on skin conductance sensors are replaceable but not
disposable, and must be changed after 50 uses to ensure an accurate reading (or sooner on
signs of corrosion). They must be cleaned with an alcohol wipe after each use.
Disposable Electrodes
Before an EMG or EKG sensor can be placed on the client, you must snap on a set of disposable
electrodes. Three types of electrodes are available from Thought Technology: Triodes, Single-
Strip and Uni-Gels. The Triode and Single electrodes are dry, while the Uni-Gel electrodes are
covered with a thin layer of conductive gel, to enhance their contact with the client’s skin. All
three types are designed like snap-on buttons. The Triode electrodes can be snapped directly
onto the sensor head. The Single and Uni-Gel electrodes are designed to be used with extender
cables.
Skin Preparation
Many physiological monitoring devices will require you to prepare the client’s skin before
positioning the sensors. Because they have high input impedance, the Thought Technology
sensors can be utilized with little or no skin preparation, depending on the purpose of your
intervention. For most biofeedback applications, simply cleaning the skin with a bit of cotton and
rubbing alcohol is sufficient to ensure good sensor readings. For EEG neurofeedback and muscle
function assessments using EMG, we recommend that you use abrasive paste and conductive gel.
Since body hair can form an insulating layer between the skin and the electrode surface, be
careful not to place the electrodes over hairy areas. In some cases, shaving may be required.
ProComp Infiniti Hardware Manual 21