Table 1 List of sensors and their respective domains and metrics

Camera

Saccades, saccades in reading

Occulomotor—eye movements

^{5, 30,31,– 32}

Novelty preference

Occulomotor—eye movements

^{22, 27}

Constriction reflex in response to stimuli

Occulomotor—pupillary response

^{12, 23, 29}

Multiple face features

Behavior—facial expressions

Microphone

Voice power spectrum and tremor

Speech and language—voice features

Vocabulary, syntactic and semantic qualities, pauses, others

Speech and language—cognition

^{7, 18,19,– 20}

Ambient noise level—dominant frequencies

Environment

Accel/gyro

Gait metrics, distance, steps, symmetry, etc

Movement—gross motor

Other activity metrics (bike, swim, run, etc)

^{6,7,8,9,– 10}

Overall activity level—energy consumption

^{79, 84}

Tremor

Movement—fine motor

^{9, 13,14,15,16,– 17}

Barometer

Gait/climb information

Movement—gross motor

Barometric pressure

Environment

Touchscreen

Swipe pattern efficiency

Movement—fine motor

Keyboard typing/tapping speed

^{9, 13,14,15,16,– 17}

Vocabulary, syntactic, and semantic qualities

Speech and Language—written text

Geoposition

Location patterns

Behavior and movement—mobility and patial memory

^{73, 78}

Driving patterns and navigational efficiency

Executive function—reaction time and spatial memory

^{82, 83}

Activity level

Movement—actigraphy

^{79, 84}

Device use

PIN and password attempts, reminders use, and more

Executive function—memory

⁹²

Number of apps used, frequency, use patterns

Executive function

^{85,86,87,88,– 89, 93,94,– 95}

Behavioral disruptions, social circle size, frequency of interactions

Behavior—social interactions

^{49, 64,65,66,67,68,– 69, 71, 72, 74,75,76,– 77}

ECG

Heart rate (HR) and heart rate variability (HRV)

ANS function—heart electric activity

System recovery metrics

^{36,37,38,– 39, 99}

Sleep patterns, phases and efficiency

Electrical activity metrics

PPG

Heart rate (HR) and heart rate variability (HRV)

ANS function—systemic circulation

System recovery metrics

^{36,37,38,– 39, 99}

Sleep patterns, phases and efficiency

Oxygen saturation (SpO₂)

IR thermometer

Skin temperature

Metabolic activity and hormonal Cycle

Immune system health, Acute illness

Ballistocardiography*

Sleep patterns, sleep phases and efficiency

Sleep

^{34, 53,54,55,56,– 57, 100}

Galvanic skin response

Skin electrical resistance

Behavior—emotional stress levels

ANS function—physical stress levels

Ambient light sensor

Light intensity at visible wavelength

ANS function—circadian rhythm

Environment

UV sensor

Light intensity at UV wavelength

Environment

Electromyogram (EMG)

Activity level

Movement—gross and fine motor

Tremor

ANS—neuromuscular system health

Seizures