Physiology

What becomes measurable during a stress response

When a situation is perceived as demanding or threatening, the autonomic nervous system mobilises physical resources. Heart rate and breathing may increase, sweat glands become more active, muscles tense and blood flow in the skin may change.

A recovery phase normally follows a limited demand. The measured signals move back towards their baseline. The size of the response and the speed of recovery vary between people and situations.

A psychophysiological stress profile records several signals at the same time. It creates a timeline in which baseline, response to tasks and subsequent recovery can be compared.

Process

How a stress profile is recorded

The measurement follows a structured sequence. Resting periods alternate with short tasks and recovery periods.

1. Baseline

The selected signals are first recorded during a resting period. This section provides a reference point for the tasks that follow.

2. Tasks

Cognitive or emotionally demanding tasks produce a time-limited activation. The curves show which signals respond and how clearly they change.

3. Recovery

Each task is followed by a resting period. This shows whether the signals move towards baseline and how quickly that happens.

4. Joint review

The practitioner discusses the curves alongside the clinical history, symptoms and relevant situation. This may guide the choice of biofeedback exercises.

Measurement channels

What each signal describes

Breathing

Breathing may become faster and shallower during activation. The profile follows breathing rate and pattern across the task and recovery period.

Heart rate and HRV

Heart rate may rise during a demand. HRV describes the variation in time between successive heartbeats and is considered together with breathing.

Skin conductance

Skin conductance changes with sweat-gland activity. The signal responds quickly to physical, cognitive and emotional activation.

Peripheral temperature

Temperature at the hands or fingers reflects changes in blood flow through the skin. It is considered over time alongside the other signals.

Muscle activity, EMG

EMG records the electrical activity of a muscle. A stress profile may monitor the shoulders, forehead or jaw, for example.

Biofeedback

How the measurement supports practice

The stress profile shows which signals respond most clearly in the situation being examined or recover more slowly. The practitioner can use this information to select a relevant measurement channel for biofeedback sessions.

During an exercise, visual or auditory feedback changes with the signal. The person tries a specific strategy, such as a breathing exercise, and can see immediately whether the measured response changes.

Several short rounds help the person recognise the response and repeat an approach that fits. Follow-up measurements show how the pattern develops across sessions.

  • Which signal responds first or most clearly during a task?
  • How does the pattern change after the task has ended?
  • Which exercise produces an observable change in the selected signal?