Operant conditioning forms bases to modern learning theories. It is a type of learning in which
the consequences of behaviour determine whether it will be repeated in the future. Positive
consequences (or rewards) constitute reinforcement while negative consequences (punishment)
leads to extinguishment or cessation of the behaviour.
Important for brain training is the evidence that these processes work also to neurons.
Excerpt from: http://en.wikipedia.org/wiki/Operant conditioning
“The first scientific studies identifying neurons that responded in ways that
suggested they encode for conditioned stimuli came from work by Mahlon
deLong and by R.T. Richardson. They showed that nucleus basalis neurons,
which release acetylcholine broadly throughout the cerebral cortex, are activated
shortly after a conditioned stimulus or after a primary reward if no conditioned
stimulus exists. These neurons are equally active for positive and negative
reinforcers and have been demonstrated to cause plasticity in many
cortical regions. Evidence also exists that dopamine is activated at similar times.
There is considerable evidence that dopamine participates in both reinforcement
and aversive learning. Dopamine pathways project much more densely
onto frontal cortex regions. Cholinergic projections, in contrast, are dense even in
the posterior cortical regions like the primary visual cortex. A study of patients
with Parkinson's disease, a condition attributed to the insufficient action of
dopamine, further illustrates the role of dopamine in positive reinforcement. It
showed that while off their medication, patients learned more readily with
aversive consequences than with positive reinforcement. Patients who were on
their medication showed the opposite to be the case, positive reinforcement
proving to be the more effective form of learning when the action of dopamine is
high.”
The nervous system is made up of nerve cells called neurons that are organized in complex
networks joined at ‘synapses’. Neurons communicate by producing chemicals called
neurotransmitters. The flow of neurotransmitters generates electric charges that help to
transfer information (or impulses) within the neuronal axons (action potential) and across the
synaptic gaps between the neurons (synaptic potential).
The brainwaves are the EEG signals that we can detect with our instruments called
electroencephalographs and the practice is called electroencephalography or EEG for short. The
EEG signals are produced by massed firings of the neurons which can be measured in terms of
Voltage or magnitude and frequency that is the number of revolutions per second (speed/time).
Different shape (morphology) and frequency of the brainwaves correspond to the function of
different processing systems in the brain and represent different states of mind.
For simplicity of our communication, we sometimes classify the variety of brainwaves into
different bands according to typical states associated with these frequencies.
The EEG Frequencies
Well functioning brain is able to self-regulate. In such a brain we expect to find good balance of
brainwaves and ability to shift easily from one brain state to another as needed in changing
situations. Healthy brains can shift easily between the frequencies as required by the
environment and function or state and task performed.
Brain deregulation can result in behavioural problems such as inattention, difficulty with
memory or sustaining a task, poor ability to maintain attention, organization and planning, sleep
disorders, depression and hopelessness or chronic pain and excessive aches exacerbated by
mental states.
Fortunately, regulation of the state within the neuronal system is a learned behaviour. Since we
now know that brain development is continuous through the lifetime, we understand that
regulatory networks can be trained and the skill becomes self reinforcing. Brain is plastic.
Neurofeedback learning is not a conscious mental process. It is accomplished on subconscious
level of brain processing. In everyday life, the brain easily integrates millions of bits of
information into a unified body and mind actions.
When we were babies learning to walk, we were not given conscious instructions. The brain
had to learn to recognise when the balance was achieved by trial & error. Once the skill was
acquired, it became effortless (a part of non-declarative memory). Normal, healthy adult does
not have to think consciously about walking. It is an effortless, automatic, subconscious task
and so the functions of the brain that are learned in the neurofeedback sessions also become
effortless with sufficient training.
(pictured – Neurofeedback system from Thought Technology)
In basic neurofeedback procedure, brain wave activity is captured by an electrode on the scalp
and analysed by a computer. The therapist sets up the placing and thresholds for desirable
increase or decrease of an amplitude (voltage) for selected frequencies relevant to the
treatment.
When brain activity moves toward chosen patterns of improved self-regulation, it is rewarded
by a graphic or sound signal such as a video game moving-on or playing a movie clip. The
feedback will stop, slow or fog-over when the brain does not meet the programmed goals.
(Thought Technology software)
(Thought technology software)
For several decades, the simple neurofeedback with one or two electrode placed on the head
and referenced to the ears or other neutral location as pictured above was the norm. The
practice involved choosing EEG amplitudes in a particular deregulated frequency bands which
were then trained up or down as required to attain better regulation. Numerous protocols were
developed for various disorders or brain deregulations mostly based on over-arousal or underarousal of the patient’s neural system. As quantitative EEG brain mapping became more
common it led to better information about training requirements of the individual.
The outcomes of these therapies are generally very good but the process may have taken up to
40 or 80 sessions. Moreover, even with the use of brain-mapping, the ‘fit’ of the protocol to the
individual brain was left to the therapist and at times may have been less than ideal.
Moreover, brain functional anatomy is complex. None of the brain functions is limited to one
location. Hence, connectivity need to be appropriately synchronised over many specific regions
of the brain. This could not be achieved by the traditional ‘amplitude’ neurofeedback.
Since late 1990s some researchers began to contemplate the use of multi-channel
neurofeedback (Thatcher 1998). In 2006 Dr Robert Thatcher introduced Z-Score EEG
Biofeedback. Currently hundreds of clinicians world-wide are practicing the whole-brain training.
The protocols were replaced by very individualized design with assistance of the Live Z-score
Training and training deeper layers of cortex i.e. LORETA neurofeedback.
LORETA stands for “Low Resolution Electromagnetic Tomography” it is a functional imaging
method developed by Swiss researchers and capable of correct localization of sources of the
EEG signals (sLORETA resolution is accurate to about 7 millimetres) in the deeper structures of
the brain cortex (Pascual-Marqui et al. 1994, 1999, 2002).
was the first psychological office in Australia offering Live Z-score
and LORETA Training since 2011. In this new Neurofeedback#1 and #2 methods, the patient’s
symptoms are re-evaluated by quantitative EEG analyses. The patient’s EEG is compared to a
database containing EEGs of well functioning individuals who were tested and screened for
healthy developmental history and were deemed free of neurological deregulations. The client’s
differences are then linked to the functional networks of the brain identified by latest research
and relevant to the client’s symptoms.
Once the patient’s dysfunctional or deregulated brain areas or inefficient connectivity (timing
of the signals in the cortex such as coherence, phase or amplitudes) are identified, the
neurofeedback training can be programmed to re-train or re-regulate these dysfunctional brain
functions according to the location of the relevant functional units in the individual’s brain
at the real time of the training.
Example of LORETA and Z-score training set-up: (Neuroguide software)
In the LORETA Live Z-Score Neurofeedback, the operant conditioning methods are used as
previously. The patients are still watching animations or movie clips, playing a game and
listening to sounds. However, the feedback will only give reward (game, sounds or picture
move-on) when the programmed dysfunctional parameters in the brain regions relevant to the
identified disorder are changing closer to statistical mean of the healthy subjects.
The difference in the LORETA or live Z-score training compared to the traditional amplitude
neurofeedback training is that the client is connected to a full set of 10/20 system of
electrodes, usually with use of the special EEG cap. The complete head of EEG is ‘read’ into
the computer where the client’s unique EEG features are compared to the database of well
functioning individuals relevant to the patient’s age group. In this way, the programme is setup to address the specific locations as well as the specific brain connectivity that is
responsible for the deregulated function of the client and give instantaneous feedback so the
brain can do it’s most important function: IT LEARNS.
The use of electroencephalography (EEG) was for a long time limited mostly to finding focus
of epileptic activity. Neurologists and electroencephalographers were traditionally looking for
gross problems like tumours, epileptic focus, paroxysmal or sharp waves by visual inspection
of the EEG records …. or ‘eyeballing’ the brain waves. The rest was considered to be just an
irrelevant ‘background noise’.
Since EEG began to be recorded by computers, it became possible (after careful visual
inspection and artifacting) to mathematically analyse the brainwaves. Thus the modern
Quantitative EEG (qEEG) is a revolutionary technique used for multi-channel qEEG analyses
and provides a wide range of mathematical tools from single channel descriptors to the
connectivity of the whole brain (Thankor 2009).
qEEG is a powerful and sensitive tool for identifying dysfunctional brain patterns or ‘bad brain
habits’. With the help of qEEG, Neurofeedback practitioners are able to assess the type of
processing that is typical for the individual and analyse its differences from a normative
sample in a data base of healthy functioning people of comparable age group. Hence we are
entering the real PERSONALISED MEDICINE targeting the specific, brain functions of the
INDIVIDUAL person.
With computer analyses of the EEG, we are able to inspect wide range of statistical
information, either tabulated in numerical form or as colour-coded topographic maps (similar
to weather maps), making it easy to identify signs consistent with poor brain regulation which
may correspond to a known pathology or interfere with the person’s flawless functioning.
References:
Kamiya J. Operant control of the EEG alpha rhythm and some of its reported effects on
consciousness. In: Tart C, editor. Altered states of consciousness. New York: Wiley; 1969
Kamiya, J. (2011). The first communications about operant conditioning of the EEG. Journal of
Neurotherapy, 15(1), 65–73.
Pascual-Marqui RD, Michel CM, Lehmann D., (1994). Low resolution electromagnetic
tomography: a new method for localizing electrical activity in the brain. International Journal of
Psychophysiology 18:49-65.
Pascual-Marqui, RD. (1999) Review of Methods for Solving the EEG Inverse Problem.
International Journal of Bioelectromagnetism, 1:75-86.
Pascual-Marqui, R.D. 2002) Methods & Findings, Experimental & Clinical Pharmacology, 24D:512
Sterman, M.B. PhD, LoPresti, R.W. PhD & Fairchild, M.D. (2010) Electroencephalographic and
Behavioral studies of Monomethyl Hydrozine Toxicity in the Cat, Journal of Neurotherapy:
Investigations in Neuromodulation, Neurofeedback and applied Neuroscience, 14:4, 293-300
Skinner, B. F. (1938) The Behavior of Organisms, Century Psychology Series
Thatcher, R. W. (1998). EEG normative databases and EEG biofeedback. Journal of
Neurotherapy, 2(4), 8–39.
Thatcher, R. W. (2009) Z-Score EEG Biofeedback: Conceptual Foundations, BMED Report
http://www.bmedreport.com/archives/6938
Thatcher, R. W. (2013) Latest Developments in Live Z-Score Training: Symptom Check List,
Phase Reset, and LORETA Z-Score Biofeedback http://www.appliedneuroscience.com/Articles.htm
Tong, S, & Thankor, N. V. (2009) Quantitative EEG Analysis Methods and Applications, Artech
House Series: Engineering in Medicine & Biology
Thought Technology http://www.thoughttechnology.com/
http://www.journals.elsevier.com/biological-psychology/
to be continued…