Skin Conductance Response (SCR), also known as Galvanic Skin Response, measures the electrical conductivity of the skin. When an individual is stressed, the sympathetic nervous system triggers sweat glands, which increases the skin's ability to conduct electricity.
This method provides an objective, real-time measure of autonomic arousal. It is frequently used in polygraph tests and biofeedback therapy to help individuals visualize their stress responses.
To ensure accuracy, SCR must be measured in both baseline (unstressed) and experimental (stressed) conditions to establish a comparative delta.
Hormonal Analysis involves testing blood, saliva, or urine for levels of Cortisol and Adrenaline. These chemicals are released by the HPA axis and the adrenal medulla during the stress response.
Physical Vitals such as blood pressure, heart rate, and respiration rate provide immediate data on cardiovascular strain. Stress often leads to higher blood pressure and increased respiration, which can even affect voice pitch.
These measures are highly reliable but often require specialized laboratory equipment and trained personnel for accurate interpretation.
| Feature | Self-Report Scales | Physiological Measures |
|---|---|---|
| Nature | Subjective (Perception-based) | Objective (Data-based) |
| Focus | Long-term life impact | Immediate biological arousal |
| Cost | Low (Paper/Digital) | High (Equipment/Lab) |
| Bias | Social desirability bias | External factors (Temp/Humidity) |
| Complexity | Easy to administer | Requires trained practitioners |
Evaluate Validity: Always consider whether a scale truly measures 'stress' or just 'change'. For example, the SRRS includes positive events like vacations, which may not be inherently distressing.
Identify Reliability Issues: Note that physiological measures like SCR can be 'noisy'. External factors such as room temperature or internal factors like caffeine consumption can skew results.
Nomothetic vs. Idiographic: Recognize that most scales are nomothetic, meaning they assume everyone reacts to a stressor (like a LCU event) in the same way, ignoring individual differences in coping.
Correlation vs. Causation: A high score on a stress scale correlates with illness, but it does not prove that stress caused the illness; a third factor, like poor diet, could influence both.
The 'Objective' Trap: Do not assume physiological measures are perfect. While they are objective, the interpretation of the data (e.g., whether high heart rate means fear or excitement) still requires context.
Ignoring Positive Events: Students often forget that 'stress' in a psychological sense includes any event requiring adaptation, meaning positive changes can still contribute to a high stress score.
