About
Neurofeedback
Neurofeedback (or EEG Biofeedback) is an experimental method that uses feedback of the
electrical activity of the brain (the EEG) in order to retrain and recondition
brainwave patterns. The EEG activity can be observed in several frequency
bands whose activity correlate with states of attention, alertness, drowsiness
and sleep. Many studies are suggesting that by training the brainwave
activity directly, the level of attention or mental states such as relaxation
and anxiety can be changed or positively conditioned.
Neurofeedback is based
on the so called "operant conditioning" which involves immediate reward of
desirable behavior or states and discouragement of undesirable behavior or
states. Essentially therefore it is an active learning process where the
EEG is used to optimize 'states' and 'attention'. Neurofeedback is not a 'therapy' in the classical 'passive' sense.
How does it work?
Neurofeedback is traditionally based on feedback of brainwave activity in
the Theta (4-8), Alpha (8-12), SMR (12-15) and Beta (16-30) frequency bands.
A number of electrodes are placed on the head (using standardized locations) and the
amplitude or power of these frequency bands are fed back with a graphical
display or auditory feedback. Slow brainwave activity may indicate
a state of inattention or drowsiness. If that is undesirable, the slow wave
activity may trained 'down' and 'faster' brainwave activity is rewarded.
Slow Cortical Potentials
Most of our equipment is also able to do neurofeedback with ultra slow
brainwave activity or slow cortical potentials. (SCP's) Recent European research
has indicated that by training the SCP it is possible to improve attention and
reduce seizure frequency.
Wideband Neurofeedback
For EEG, the NeXus series of products support a wide frequency band from
DC (0Hz) to 100Hz or even higher. Because NeXus requires no notch filters (50/60Hz) its
means the entire frequency band, including real gamma (35-45 Hz) is available. |
Real-time feedback of the electrical state of the brain. NeXus supports both the regular EEG as well as slow cortical potentials. (DC-EEG)
An example of EEG feedback using fractal graphics projected
with an LCD beamer. |
Clinical Applications
Neurofeedback has been tried for many types of applications
but only for a few applications one could say that Neurofeedback may be efficacious. (2008) These
applications include:
- Attention disorders & Learning Disabilities
- Epilepsy and seizure disorders
There are indications that Neurofeedback (NFB) may also be useful for treatment
of anxiety, stress, depression, drug abuse and sleep disorders, but we believe these areas require
more research before anything more definitive can be said. For some of these applications, Biofeedback rather than Neurofeedback may actually be a better choice.
What is QEEG?
Quantitative EEG is based on a statistical and numerical analysis of the
digital EEG. Usually a large number of EEG channels are recorded (typically
16-32) by using an EEG cap. After recording the digital EEG data is then
de-artifacted and exported to special QEEG database analysis software. This
software performs a digital analysis of the EEG and compares the statistical
results against a large database of children and adult EEGs in order to assess
any deviations. The results are displayed numerically and in the form of
topographical EEG maps.
QEEG is used as a neurometric method of assessing variations in the
brain function. It is complementary to Neurofeedback training. We advise that
only well trained experts use QEEG. The NeXus-32 system
supports QEEG recordings of up to 24 or 32 EEG channels. |
A screenshot from the Biotrace+ (NeXus-10) software displaying
EEG spectral analysis
An example of 24 channel QEEG data
acquisition (using NeXus-32 shielded electrodes) |
Should I use Neurofeedback?
We advise any clinician or health professional who is interested in
neurofeedback, to first study this field, read the literature and go through
several workshops before considering offering
it to clients/patients. We strongly advise that only health professionals who
have suffficient training or a medical background (for instance neuro-psychologists, neurologists
psychiatrists or pediatricians)
apply this technique.
Some words of caution: when
you actually use the equipment on patients, only use equipment that has
medical certification and thus proven to be safe and reliable. Mind Media (founded
1992) has over
16 years of experience in the Neurofeedback field. Our conclusion is that Neurofeedback is promising for some applications, but we always tell people not to expect miracles. It is an experimental method and not a panacea (cure for everything).
|
Multiple bands (Theta, Alpha, Beta) can be used for feedback. Frequency band
settings can be changed on the fly. |
Neurofeedback for Children
Our systems can be used for neurofeedback training with adults or
children. For children we have developed custom design computer games (used
inside BioTrace+) that respond to EEG activity and the level of attention
observed in the EEG signals.
BioTrace+ offers real-time Neurofeedback using computer games
and DVD multimedia. |
Useful Web Links
Apart from our own workshops and trainings there are many other
organizations that offer good information or workshops. Here are some web links
with useful information:
Society of Applied Neuroscience
International Society for Neuronal Regulation (ISNR)
Association for Applied Psychophysiology and Biofeedback (AAPB)
Deutsche Biofeedback Gesellschaft e.V.
Federation of European
Neuroscience Societies
Stens
Neurofeedback Training (USA)
more links... |
