What is Neurofeedback?

Neurofeedback is a special form of biofeedback and is based on the measurement of brain activity. For this purpose, electrodes are attached to the scalp in order to derive electrical signals from the brain in real time using the electroencephalogram (EEG).

Certain parameters of this activity are then evaluated by a computer and used as feedback signal. The patient receives feedback about the current activity of his brain on a screen. The feedback can be a graphic or animation that moves accordingly or a melody that gets louder and softer. The brain is thus “held up to a mirror”: it constantly receives conscious or unconscious feedback about what it is doing at any given moment.

By means of this feedback it is now possible to train certain parameters of brain activity and the self-regulating ability of the central nervous system. In this way, the activity of the brain and symptoms of diseases can be better regulated.

Neurofeedback – individualized therapy?

Today there are different approaches available, which differ mainly in which parameters are fed back from the EEG and how they control the feedback. There is always a debate whether a “one-size-fits-all” approach, such as classical frequency band training, or an individual approach, such as ILF training, in which changes in patient symptoms are the main focus of Neurofeedback training, is preferable.

The advantages and disadvantages of these different approaches can be summarized as follows: A “one-size-fits-all” approach can be learned quickly and more easily investigated through studies. An individualized approach is therapeutically more demanding and complicates the scientific investigation. The results cannot easily be repeated because the training parameters are individually adapted to the patient.

What is Neurofeedback used for?

Today, Neurofeedback is mainly used in the treatment of ADHD. The American Peadiatrics Society has already proposed Neurofeedback as an evidence-based treatment method for ADHD, and in Germany it is also mentioned in the guidelines for the treatment of ADHD.

However, since it is a method that can be used to specifically train the activity and self-regulating ability of the central nervous system, the current range of applications is quite broad. Neurofeedback is used as a therapy component in the treatment of various neurological diseases.

Neurofeedback should always be seen in the context of an overall treatment strategy. It is a therapy component in addition to, for example, other medicinal or behavioural therapy measures. In addition, the treatment must always be accompanied by an appropriately trained doctor or therapist and should - like other treatment methods - only be carried out after a thorough diagnosis and anamnesis.

Neurofeedback is used in the non-medical field, especially for athletes in the form of so-called "peak performance" as a training method to improve concentration and performance.

  • Attention deficit hyperactivity disorder (ADHD) is probably one of the most discussed conditions of childhood and adolescence. It is little known that the disorder can extend into adulthood if left untreated.

    Today, scientists see a central regulatory disorder in the brain as the main cause. The processing of information between different regions of the brain is disturbed. Other accompanying causes can be psychological and social conditions. Concentration disorders, hyperactivity and impulsivity often occur in affected children. These symptoms can lead to difficulties both in everyday life and at school.

    Not every restless child suffers from ADHD right away, so observation of the symptoms over a longer period of time by an experienced doctor or psychotherapist is needed. Long-term observations by teachers can also be included in the assessment of the behaviour of a possibly affected child. However, if left untreated, further symptoms can develop into adulthood, including general poor performance, disorganisation and mood swings, making it considerably more difficult to cope with everyday life.

    The use of Neurofeedback as part of the overall treatment is primarily aimed at improving concentration and attention. It can be used with both children and adults. Whether Neurofeedback can be a useful component of therapy can only be determined after a thorough diagnosis by a treating doctor or therapist.

  • Autism spectrum disorders manifest themselves in a range of symptoms. These vary in severity and characteristics. These include withdrawal into a world of one's own thoughts, avoidance of contact with the environment, impairments in language and motor skills, low empathy for the feelings and needs of others, stereotyped movements and behaviours, and avoidance of physical contact.

    Autism spectrum disorders cannot be cured, but their severity can be treated. As the symptoms vary, treatment must be flexible and individualised. Neurofeedback can be one of the building blocks of a behavioural treatment plan. However, whether Neurofeedback can be a component of treatment depends on the severity of the condition and, more importantly, the associated symptoms. For this reason, treatment is preceded by a thorough, individualised history and diagnosis.

  • Pain is registered by pain receptors and the corresponding impulses are processed by nerve cell structures. If these structures are constantly exposed to pain impulses, the sensation can be "stored". A "pain memory" develops. As a result, after the original cause has been reduced or cured, even small stimuli may be enough to cause pain. Chronic pain develops.

    The brain activity of people with chronic pain differs from that of other people, even at rest. This activity can be visualised using an EEG. Studies have shown that especially the theta and beta parts of the EEG are altered and particularly pronounced.

    When Neurofeedback is used for chronic pain, it should be part of a complex pain therapy. The approach is to normalise the dysregulated brain activity. Biofeedback and Neurofeedback methods are mainly used for muscular tension pain, fibromyalgia or migraine. The latter is characterised by recurrent attacks of severe throbbing headaches, often accompanied by nausea, dizziness and sensitivity to light.

    Whether Neurofeedback can make a positive contribution to pain control and pain management must, as with all other areas of application, always be assessed by a doctor after a thorough diagnostic assessment.

  • Epilepsy is a neurological disorder in which nerve cells send out disruptive signals. This leads to seizures of varying severity, with uncontrolled muscle movements, convulsions and loss of consciousness. Epileptic seizures are one of the most common neurological disorders.

    Neurofeedback was originally discovered in relation to epilepsy. Over time, it has evolved into classical frequency band training, because large parts of the brain waves oscillate at a low frequency during epileptic seizures. The aim of Neurofeedback is to train people to control the slow frequencies and regulate them down to minimise the likelihood of a seizure occurring.

    Whether or not Neurofeedback can be a useful component of therapy needs to be assessed by a doctor or therapist. Even if the seizures do not disappear completely, the quality of life can often be greatly improved as part of a holistic therapy.

  • Tinnitus has become an increasingly common condition. Many people with tinnitus are chronically ill and suffer from the constant ringing in their ears. The sounds are fixed in the brain and become independent of the original trigger, similar to phantom pain. Studies and research, for example at the Römerwallklinik Mainz and the university hospitals in Mainz, Constance and Marburg, have shown that Neurofeedback can be a therapeutic component. The main aim of the treatment is to teach people to change the rhythm of their oscillations in order to reduce stress and volume.

    Whether or not Neurofeedback can be a useful addition to therapy must be assessed by a trained doctor or therapist, as with all areas of application. In the case of tinnitus in particular, the cause of the tinnitus will determine whether Neurofeedback is a useful addition to the treatment.

  • Surveys show that the 12-month prevalence of post-traumatic stress disorder (PTSD) is around 1% worldwide and 0.5% in Germany. The lifetime prevalence is around 4% worldwide and 3% in Germany. Typical symptoms include the involuntary re-experiencing of stressful memories, flashbacks and sleep disorders, which manifest themselves in avoidance behaviour, changes in mood and cognition and changes in arousal, among other things.

    PTSD is triggered by exposure to one or more traumatic experiences, such as war or war operations, natural disasters or sexual assault. Existing psychiatric disorders, for example, as well as socio-demographic factors such as female gender, young age and low income, increase the likelihood of occurrence.

    A common and very effective form of therapy is cognitive behavioural therapy, in which the brain is taught new behavioural patterns through extinction. Increased amygdala activity has been reported in PTSD, but reduced activity in the hippocampus and the ventromedial section of the prefrontal cortex (vmPFC). The amygdala is responsible for categorising and recognising danger, whereas the prefrontal cortex controls the fear response. Memories are stored in the hippocampus. If the hippocampus malfunctions, traumatic memories are involuntarily recalled, which can lead to flashbacks and nightmares. In addition, there is increasing evidence of dysfunction of various networks, such as the central executive network, the salience network and the resting state network in PTSD. With the help of neurofeedback, it is possible to improve the brain's ability to self-regulate. There have been studies on the use of neurofeedback for PTSD since the early 1990s (Peniston and Kulkosky) and in recent years in particular, PTSD has become the focus of research and there are numerous publications in this area as a stand-alone form of therapy, but also as a supplement to other forms of therapy. The individualized approach of ILF neurofeedback is particularly advantageous here, as a broad spectrum of symptoms occurs.

What Neurofeedback methods are there?

The basis of all Neurofeedback procedures is still the classical frequency band training. Even today, Neurofeedback is mostly explained using this method. Over time, different methods have developed.

The individual Neurofeedback methods differ mainly in which parameters from the EEG control the feedback. In the following, you can find more information about the common, different methods.

  • Frequency band training – the origin of Neurofeedback

    Classic frequency band training has existed since the early 1970s and is still the basis of modern Neurofeedback procedures. Thanks to ever-improving software and the associated possibilities for signal processing and feedback display, classic frequency band training has been constantly evolving. This is why it is still in use today.

    It is based on the assumption that certain frequency ranges have a favorable effect on the regulation of disease-related symptoms.

    The principle of operant conditioning

    The principle of action is explained by operant conditioning, i.e. “learning through reward”. In this Neurofeedback procedure, threshold values are determined in a selected frequency range. This means, on the one hand, frequencies are set at which a “reward” (reward frequency) is given. On the other hand, there are those where the “withdrawal of reward” (inhibit frequency) takes place.

    As soon as the amplitudes in the respective frequency range exceed the threshold, a reward is given. An animation moves on the monitor or a sound or tone is heard when the target frequency is reached.

    However, if the amplitudes fall below the threshold in the respective frequency range, no more reward is given via the screen. In this case, the brain has slipped into a misregulation. For example, the graphic stops and no sound or tone is heard.

    The aim of frequency band training is to reinforce the desired behavior by providing an incentive. In this case, the behavior is a desired target frequency. The incentive is rewarded by a corresponding display on the screen.

  • ILF stands for infra low frequency and is a method that has developed from classic frequency band training. Based on the classic frequency band training , this method was further developed based on criteria of clinical success. In addition to classic frequency band training and central electrode positioning, other frequencies and electrode placement were systematically examined.

    Individual Neurofeedback therapy

    In ILF Neurofeedback, it is assumed that the appropriate reward frequency depends neither on diagnosis nor on EEG data. Rather, it is very individual and can be adjusted for each individual patient based on their reaction to the training. For each patient, ILF Neurofeedback continuously aims to optimize the reward frequency in a kind of fine-tuning. Similar to the fitting of spectacle lenses, where the individual lens strength is found by questioning the patient when changing lenses, ILF Neurofeedback asks and observes the effect of different target frequencies on the patient.

    When changing the reward frequency, it is often possible to observe very rapid changes in status depending on the selected reward frequency. This is noticeable in the level of arousal, in the level of attention and often also in the mood. Often during a session you will find the optimal reward frequency at which the currently existing symptoms are reduced and the patient achieves a pleasant state of relaxation. In some cases, however, the optimal frequency is not immediately recognizable in the session and you have to orientate yourself to the symptom changes after the session in order to optimize the training frequency.

    Training effects across a wide frequency spectrum

    With this new optimization strategy, training effects can be investigated over a broader frequency spectrum than the case with classic frequency band training since then. Over time, clinical outcomes continued to move towards slow potential changes. For this reason, in the following years, the focus was placed on further analyzing the training in the slower frequencies, even below 0.1 Hz, the infra-low range, which has only been technically possible since 2006.

  • SCP – Slow Cortical Potentials

    SCP stands for slow cortical potentials. The SCP fall under the so-called event-related potentials, i.e. waveforms in the EEG, which are created, for example, through sensory perceptions or through changes in attention, for example, when one is in a state of expectation.

    Regulation of attention

    The SCPs are not frequencies, but the slow shifts of the entire EEG in an electrically negative or positive direction. A shift into the negative range is associated with a higher excitability; the nerve cells are stimulated at the same time. In return, a shift to the positive range is accompanied by a reduction in excitability. The SCP therefore play an important role in regulating attention.

    SCP-Neurofeedback – Differences to classic frequency band training

    While the classic frequency band training is a continuous training over 20-30 minutes, in which the amplitudes that exceed or fall below in selected frequency bands are rewarded, SCP training is mainly based on time intervals. At the beginning of each session, the patient is given the task of deliberately making the current DC voltage signal more positive or negative for the next 8 seconds. As a rule, approximately 80 rounds of 8 seconds each are carried out per session. In addition to direct feedback during the 8 seconds, the patient receives an optical signal (e.g. a sun or a smiley face) at the end of each 8 second run if the run is rated as successful.

    This process was shaped by the working group led by Niels Birbaumer at the University of Tübingen and probably still offers the most qualified studies in the field of Neurofeedback.

  • QEEG and Z-Score Training

    Since the late 1990s, the development in the field of Neurofeedback has been moving towards individualized therapy. One approach that has emerged in this context is the QEEG – the quantitative EEG. The EEG data collected are compared with those from a standard database. The theory behind this is that certain clinical pictures or symptoms can be identified from the comparison with standard data and the Neurofeedback training can thereby be individualized. The QEEG method is therefore actually in the field of neurodiagnostics, although the diagnostic possibilities are still controversial. Thus, there are currently only a few clinical pictures for which there are first indications of effectiveness of this method.

    What does Z-Score mean?

    The “Z-Score” is also closely related to the QEEG. The Z-Score is a statistical value that indicates how far the value measured for an individual is from the mean value of a measured comparison group (standard value).

    The question repeatedly arises whether there are endophenotypes for neurological disorders, i.e. certain features that can be read in the QEEG and can be used as biological markers, so to speak, to recognize diseases. There are first indications for such endophenotypes, which are determined from various parameters of the QEEG, for example for ADHD, schizophrenia and anxiety disorders.

    QEEG and Z-Score Training – the basis for individual Neurofeedback therapy?

    It remains questionable to what extent this data can be used for personalized Neurofeedback training. In practice, the Neurofeedback protocols derived from the QEEG generally correspond to the conventional SMR / Beta protocols of classic frequency band training, in which SMR and beta amplitudes are rewarded and slower and faster frequency bands are inhibited.

    This may be due to the fact that the diagnostic value, which results primarily from the measurement of event-related potentials in the QEEG and the corresponding calculations, cannot be converted 1: 1 into frequency band training. Although QEEG data are the most useful diagnostic tools for ADHD, a recent study showed no significant differences in the improvement of ADHD symptoms between a control group with placebo feedback and a QEEG Neurofeedback group.

    In the treatment of reoccurring migraine attacks, however, Walker (Neuroscience 2011; 42: 59-61) was able to show a drastic reduction in migraine attacks after the QEEG Neurofeedback training.

  • Tomographic Neurofeedback using imaging techniques

    Tomographic Neurofeedback using fMRI (functional magnetic resonance imaging), i.e. imaging techniques, is currently of great interest in research.

    In common Neurofeedback procedures, changes in the electrical potentials on the cortex surface are used as parameters for Neurofeedback; i.e. those signals that are generated at the outer edge of the brain in the thin layer of the cerebral cortex. The tomographic Neurofeedback offers the possibility to report back the activity from deeper brain regions in a three-dimensional resolution.

    First approaches in emotion control and the improvement of pain experiences

    This is of particular interest in the regulation of emotional control, such as the regulation of the so-called amygdala activity, i.e. the almond kernel complex – a brain region of the limbic system – which is important in the development of fear and emotions, among other things. In order to regulate the pain experience, there are first approaches that intend to modulate the activity of the so-called anterior cingulate cortex (ACC).

    The tomographic Neurofeedback naturally offers many interesting therapeutic approaches. Due to the high effort and the costs involved, these are currently mostly not practical in everyday clinical practice.

    sLORETA

    One way to operate tomographic Neurofeedback at low cost is to combine Neurofeedback with sLORETA (Low Resolution Brain Electromagnetic Tomography) software.

    sLORETA is a mathematical procedure with which it is possible to determine the sources of potential changes measured on the cranial surface of the skull and to use them for the three-dimensional source analysis of the signal. In this way, Loreta-Neurofeedback can be used to train selected frequency bands based on the source.

    However, the process has not yet been sufficiently evaluated and is still under development.

Important note:

The information on this page is not intended to be a substitute for professional advise or treatment by trained and recognized doctors and therapists. The content of this page may not be used to independently diagnose or start treatment.