In biofeedback, measurements of various physiological parameters of the patient are taken (pressure, heart rate, temperature, sweating, muscle contraction, etc.), the data is analyzed, and then the patient is informed of the results of the measurements (e.g. through a characteristic sound), so that he can self-regulate his physiology. After practice, the patient learns how to cause voluntary changes in the psychophysiological functions of his body, such as blood pressure, temperature, the tension of specific muscles, etc. At peopleforward.gr we conduct biofeedback sessions to control anxiety, which is responsible for a multitude of problems such as sleep problems, headaches, etc.

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Neurofeedback is a biofeedback technique in which the local electromagnetic activity of the brain, produced by its biochemical function, is amplified and analyzed in specific ranges of brain wave frequencies. This is done by placing 2 sensors on the scalp. The individual monitors this activity and tries to self-regulate it, without external intervention procedures. The entire process of training the individual in the control of their brain waves is based on the principles of operant learning and the goal is achieved gradually with frequent repetition of sessions (2-3 per week). The 'reward' is reported when the individual (1) manages to regulate their brain waves so as to maintain the intensity of a specific frequency band higher than a threshold limit set by the psychotherapist (2). The reward can be a musical pattern, a video or a game (3) that is played if the goal is achieved, i.e. the desired frequency limit that has been predetermined as a therapeutic goal. The goals are determined by frequency norms by age, topography and symptomatology that have been weighted using QEEG in the general population.

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The use of neurofeedback has been shown to be effective in individuals suffering from ADHD/ADD or who experience difficulties with concentration and attention. Another well-known neurofeedback protocol is the Peniston protocol, which has been shown to contribute to positive changes not only in cases of post-traumatic stress but also in increasing intellectual and artistic performance. The interventions require 2-3 half-hour meetings per week that are reduced as the intervention progresses. Depending on the goal of the intervention, 20-40 sessions are usually required.

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They are offered in pre-agreed packages of 12 40-minute sessions, a reassessment is made and a decision is made whether or not to continue the intervention.

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Brain waves are categorized into 5 basic frequency ranges, a brief description of which follows:​

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Delta (1-4 Hz)​

It is a frequency that characterizes the 4th stage of sleep. Thatcher (1999) states that while 40% of the frequencies of an infant up to 6 months old, consists of Delta frequencies, however in the adult the normal levels of Delta occupy less than 5% of the amplitude of the brain waves. Therefore the excessive presence of the Delta frequency refers to problems, the type of which depends on the topology.

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Theta (4-8 Hz)

Theta brain waves are generally associated with reduced brain activity, such as in states of "half-asleep," daydreaming, and meditating. The 7 Hz frequency is at its peak when the individual is creating mental images, while in peak performance states, high values ​​of 6-8 Hz are observed for a short period of time during cognitive processing of information. The Theta/Beta frequency ratio in the kinesthetic area in children with ADHD is particularly high (>6).

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Alpha (8-12 Hz)

Frequencies of 9-13 Hz are often seen in adults in a state of wakefulness, while in a state of drowsiness, frequencies of 7-8 Hz appear with greater intensity. Slow changes in the Alpha frequency between these two states can be considered an indication of problems with mental flexibility and memory. The Alpha frequency is associated with a sense of inner calm.

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SMR (12-15 Hz)

SMR frequency becomes particularly important in people with hyperactivity and impulsivity problems.

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Beta (15-21 H G)

When our attention is focused on our interlocutor or when we are in the process of solving a problem, Beta frequencies show an increase. The same is true when we ask a child to calculate the product 9 X 6: then we can observe a sharp increase in the intensity of the 17 Hz frequency with a simultaneous decrease in the intensity of the Theta and low Alpha frequencies. Beta in normal situations usually shows maximum intensity in the front-central areas of the head.

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High Beta (21-32 Hz)

High Beta frequencies are generally associated with states of intense cognitive processing that may include excessive worry, anxiety, rumination, excessive thinking, and obsessive-compulsive behaviors, particularly when detected in the anterior cingulate gyrus (part of the limbic structure considered the emotional center of the brain).

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Gamma (32-40 Hz)​

The Gamma frequency (binding rhythm) has been observed to be important in learning processes and may be related to the type of attention where the individual recalls different aspects of the same subject in order to gain an overall understanding of it.

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Brainwave frequencies in the EEG (electroencephalogram) are closely related to various mental disorders, such as anxiety, depression, and OCD, through changes in the power and balance of the bands: delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), beta (13–30 Hz), and gamma (>30 Hz).

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Anxiety (Anxiety disorders, GAD, panic)

• Excessively high beta (especially high beta >20-30 Hz) and gamma → hyperactivity, hyperarousal, overthinking, restlessness, tachycardia.

• Reduced alpha (especially in frontal/occipital) → less relaxation, difficulty calming down.

• Neurofeedback often: ↑ alpha (8–12 Hz) for relaxation, ↓ high beta to reduce hyperarousal, or ↑ SMR (12–15 Hz) for calm focus. Results: symptom reduction of 50–70%+ in many studies.

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Depression

• Excessively high beta (especially high beta >20-30 Hz) and gamma → hyperactivity, hyperarousal, overthinking, restlessness, tachycardia.

• Reduced alpha (especially in frontal/occipital) → less relaxation, difficulty calming down.

• Neurofeedback often: ↑ alpha (8–12 Hz) for relaxation, ↓ high beta to reduce hyperarousal, or ↑ SMR (12–15 Hz) for calm focus. Results: symptom reduction of 50–70%+ in many studies.

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OCD (Obsessive-Compulsive Disorder)

• Increased delta (0.5–4 Hz) and theta (4–8 Hz), especially in fronto-temporal/parietal areas → hyperactivity in "slow" zones, associated with obsessions/repetition.

• Sometimes excess beta (midline/frontal, e.g. anterior cingulate) → excessive focus/anxiety.

• There are subtypes: excess alpha + frontal beta, or excess theta.

• Neurofeedback often: ↓ excess beta/high beta, slow waves (delta/theta) modulation, or anterior prefrontal cortex training (fMRI-based). Improvement in Y-BOCS scores 6–9 points, response rates 70–90% in some studies (especially adjunctive to CBT).

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General picture

In many disorders (including anxiety, depression, OCD), a shift to lower frequencies (↑ delta/theta) and a decrease in higher frequencies (↓ alpha/beta/gamma) is observed in the resting-state EEG – an indication of hyperactivity in “slow” networks and hypofunction in regulatory/relaxing ones.

Neurofeedback trains the brain to regulate these frequencies (e.g. ↑ alpha for calm, ↓ high beta for less anxiety), promoting long-term self-regulation with minimal side effects. Protocols are often individualized with qEEG for best results.