Thought Technology Ltd. Procomp Infiniti, Руководство по оборудованию

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Operating Principle
The temperature sensor is called a thermistor. This device converts changes in temperature to
changes in an electrical current. The body's peripheral temperature, as measured on its
extremities, will vary according to the amount of blood perfusing the skin. This, in turn, is
dependent on the client's state of sympathetic arousal. As a person gets stressed, their fingers
tend to get colder. Relaxation training involves learning to voluntarily increase the finger
temperature.
Measurement Unit
Temperature is measured in degrees Fahrenheit or degrees Celsius.
Sensor Placement
The temperature sensor can be strapped to the dorsal or palmar side of any finger or toe using
the short strip of Velcro that is provided with the sensor. Remember to clean the thermistor bead
with an alcohol wipe between clients.
Typical Signal
Peripheral temperature changes are fairly slow and do not have much amplitude. To monitor
temperature changes effectively, it is necessary to have a fairly small vertical scale size.
BLOOD VOLUME PULSE
Sensor Type
To record blood volume pulse (BVP) on the
ProComp Infinity, use the BVP-Flex/Pro
sensor.
Operating Principle
BVP, also called photoplethysmography, bounces infra-red light against a skin surface and
measures the amount of reflected light. This amount will vary with the amount of blood present
in the skin. At each heart beat (pulse), there is more blood in the skin - blood reflects red light
and absorbs other colors - and more light is reflected. Between pulses, the amount of blood
decreases and more red light is absorbed. This measure is an indication of vasomotor activity and
of sympathetic arousal.
Measurement Unit
The BVP signal is a relative measure. It does not have a standard unit. From the BVP signal, the
software can usually calculate heart rate and inter-beat interval. The amplitude of the BVP
deviation can also be a useful measure.
ProComp Infiniti Hardware Manual 31