Temporal Summation

Psychophysical rating of pressure stimuli given in quick succession that evokes temporal summation.

The temporal summation procedure applies a series of rectangular pressure stimuli to one or both cuffs. The participant is asked to rate the pain sensation of these stimuli on the VAS meter as soon as possible after the cessation of a pressure stimulus. The VAS rating for a stimulus is recorded just before the next stimulus is given or would have been given if it had not been the last stimulus in the series.

The procedure window for the <algometry-temporal-summation> procedure is shown in Figure 1. The procedure window consists of two areas: applied pressure and recorded responses.

Figure 1: Procedure window of the temporal summation procedure

The applied pressure area will display a legend indicating which cuff outlet(s) will be active and will plot the applied pressure over time. The pressure is annotated with the psychophysical rating of each pressure stimulus.

Please see Algometry page for an introduction to the cuff pressure procedures and concepts that are common for these procedures before reading the rest of this procedure documentation.

Procedure definition

A temporal summation procedure can be defined with the <algometry-temporal-summation> element within the <procedures> element in the Experiment Definition File (*.expx):

<algometry-temporal-summation id="AP2TSum" 
    name="Temporal Summation (Stop on VAS 10) [Cuff 1]"
    experimental-setup-id="vas"
    no-of-stimuli="10"
    pressure-static="0"
    pressure-stimulate="AP2SR02.PTT"
    primary-cuff="1"
    second-cuff="false"
    t-on="1"
    t-off="1">
    <dependencies>
        <dependency id="AP2SR02"/>
    </dependencies>
</algometry-temporal-summation>

Listing 1: Definition of a temporal summation procedure

Listing 1 has the following procedure specific attributes:

Attribute Type Specification
no-of-stimuli int = Calculated(context) The number of pressure stimuli applied during the procedure
pressure-static double = Calculated(context) The pressure that will be applied in between the pressure stimuli. This value is included as a slight static pressure between the stimuli can prevent the cuff from shifting during the procedure.
pressure-stimulate double = Calculated(context) The pressure that will be applied during the rectangular pressure stimuli.
primary-cuff int=Calculated(tc) Determines which cuff (1 or 2) will be used for the pressure stimulation.
second-cuff bool Inflate the second cuff together with the primary cuff.
t-on double = Calculated(context) The duration of the rectangular stimuli.
t-off double = Calculated(context) The pause between the stimuli in the series.

Scripting (Properties)

In addition to the properties that are common to all procedure results, the temporal summation procedure result has the following procedure specific properties:

Name Type Specification
SecondCuff bool Was the second cuff inflated in parallel with the first cuffs (spatial summation).
PrimaryChannel int What was the primary cuff channel. Please note this is only relevant if second-cuff is False.
MaximalPressure double Maximal allowed pressure during the procedure.
MaximalTime double Maximal time of the procedure. Please note this will be longer than the actual running time if the participant was a responder.
NominalStimulatingPressure double Stimulating pressure.
NumberOfStimuli int The number of pressure stimuli applied during the procedure.
TimeOn double The duration of the rectangular stimuli.
TimeOff double The pause between the stimuli in the series.
Responses List<double> Ratings of each stimulus in the temporal summation.
ResponseTime List<double> Time points at which the ratings where sampled.
StimulationPressure List<double> Stimulation pressure during the procedure.
VAS List<double> Rating of the stimulation pressure during the procedure.
Time List<double> Time of the values in the StimulationPressure and VAS data points.

Example protocols