Table 2.

Overview of the static and dynamic features, calculated for each physiological signal

Feature Name	Blocks	Static or Dynamic	Explanation of Features
Mean	R2, R3, R4, S1, S2, S3	Static	Mean of the physiological signal in the rest/stress block
Standard deviation	R2, R3, R4, S1, S2, S3	Static	Standard deviation of the physiological signal in the rest/stress block
Trend means of stress phases	S4 − S2, S4 − S3, S3 − S2	Static	Difference between the means of different stress phases, eg, S4 − S2
Trend means of rest phases	R4 − R2, R4 − R3, R3 − R2	Static	Difference between the means of different rest phases, eg, R4 − R2
Response time	S1, S2, S3	Dynamic	Time in seconds to reach the maximum (HR and GSR)/minimum (ST) starting from the onset of the stress task
Recovery time	S1, S2, S3	Dynamic	Time in seconds to reach the minimum (HR and GSR)/maximum (ST) starting from the onset of the rest phase
Slope	R2, R3, R4, S1, S2, S3	Dynamic	Slope of a straight line fitted through physiological signal in the rest/stress block
Trend response times	S4 − S2, S4 − S3, S3 − S2	Dynamic	Difference between the response times of different stress phases, eg, S4 − S2
Trend recovery times	R4 − R2, R4 − R3, R3 − R2	Dynamic	Difference between the recovery times of different rest phases, eg, R4 − R2
Trend slopes of stress phases	S4 − S2, S4 − S3, S3 − S2	Dynamic	Difference between the slopes of different stress phases, eg, S4 − S2
Trend slopes of rest phases	R4 − R2, R4 − R3, R3 − R2	Dynamic	Difference between the slopes of different rest phases, eg, R4 − R2

Abbreviations: GSR, galvanic skin response; HR, heart rate; R, rest phase; S, stress task; ST, skin temperature.