Our brains enable an array of amazing properties that we enjoy unconsciously on an every-day, every-moment basis: We listen to great music and react with limb movement and emotional involvement, almost as if it were automatic, natural and intuitive. We exercise and practice strenuous kinds of sports to feel better afterwards, we transmit basic emotions of fear and disgust onto certain situations at our home and objects in our workplace, we prefer certain foods for dinner, unconsciously we even lean towards a favorite gait to imitate our best friend, we choose a favorite person we´d like to date, a favorite country we´d like to live in, and so on. Starting from its very foundation, all these circumstances have to do with neuronal learning and neuronal plasticity, which are fundamental functions of our brain.
Mechanisms of neuronal learning and reorganization are the backbone of a (not quite) novel technique called “neurofeedback”: Humans learn in many ways, e.g. by means of success and failure, by social imitation, by modeling the behavior of others as well as by association of stimuli that have a close relationship in time and place with each other. In neurofeedback, the brain somehow learns from itself: Brain activity from certain regions can be literally shown to a human being as a visual graphic on a computer screen. A certain visual aid, e.g. a rising thermometer, then represents levels of ongoing brain activity. But how is this done?
Usually, a therapist gives an instruction to the patient: “Let the thermometer rise!”, or: “Let the thermometer fall!”. Successfully achieved instructions are then actively reinforced by the therapist and positive verbal praise or a monetary reward is given to the subject. Thus, the organism can adjust its response accordingly, thereby enabling conscious learning processes
Neurofeedback proves valuable for people dealing with tension headaches for example, as even relaxation can be learned. What sounds like magic gets much clearer when you try it out personally: A feedback session starts with placing a cap of EEG-electrodes on your head to acquire an electromagnetic signal from your scalp. By now, you as a participant can already be instructed to alter the shape of the brain wave displayed on the computer screen in front of you. If the brain signal belongs to a problematically altered frequency activation curve, for instance habitually inducing your tension headache, you are instructed to lower the frequency or the amplitude of the curve seen on the screen. Operant conditioning – that is: learning by success or failure – is now used to reward the participant for every successful alteration of the feedbacked brain wave. The patient directly receives reward in the realm of small financial compensations or verbal praise. Like this, unconscious brain activity is made conscious using this technique, and either EEG electrodes or fMRI scanners are the method of choice.
Yes, you heard it correctly: An fMRI scanner can be used to execute neurofeedback as well. To enable fMRI neurofeedback, climb into the next magnetic resonance machine you can find. Then, let an electromagnetic signal be recorded from your brain. It is shown to you via a computer screen within the scanner and it can look like a thermometer, a vertical bar, a sinus curve, etc.. Feedback paradigms can look very differently and are usually custom-made for the underlying research question at hand. The best part: Neural signals can be acquired from any part of the brain, as long as the region is interesting enough for the process wanted to study. In patients suffering alcohol addiction, e.g. the dorsolateral prefrontal cortex (dlPFC) and the anterior cingulum (ACC) are regions of interest for the processing of conscious suppression of alcohol craving.
The visualization of the brain signal can help the patient actively shape his own mind and a training of neural responses toward e.g. stressful alcoholic stimuli occurs. However, it is crucial for the effectiveness of this technique that even small successes in neurofeedback training are reinforced as newly learned behavior has to be built up step by step in the first place. Additionally, a real-life transfer from the experimental situation onto any given real-life situation would be the final goal – but it is also the hardest one: Habits have to be formed in the first place so that they can be unconsciously available in high-stress situations, for instance when the patient craves a drink. Not a single human action is easily executable when you first learn it, especially when humans are situated outside of the sensitive phases of development during their childhood and early adolescence. But one important aim is clear: Brain regulation executed in real-life should in the end work as seamlessly as tapping your foot while groovin´ out to your favorite rock song.
Current findings are a far cry from that, when we look at empirical evidence with mixed effectiveness ratings regarding therapy outcomes. There is a huge difference between executing one successful neurofeedback session in the scanner and upregulating your dorsolateral prefrontal cortex willingly while you´re watching the next best liquor ad in the newspaper. The real-world transfer outside of the lab is a giant leap for most people trying out neurofeedback therapy.
A promising step further is using the neurofeedback method in conjunction with connectivity measures of brain networks, enabling better localization, regulation of connectivity between regions of interest as well as higher temporal resolution of processing stages in real time. Separate brain areas and their interconnections can be visualized by means of time course analysis using functional magnetic resonance scanning. This is also known by the name of “real-time fMRI brain computer interface (rt fMRI – BCI)”.
What sounds like science fiction, is just merely the precise use of activation time courses and correlations of two or more circumscribed target regions, enabling a more accurate feedback towards the user. In treatment of alcohol addiction for instance, patients should be empowered to use their very own prefrontal self-control networks and the skills for making planned and goal-directed decisions innately programmed within these regions. Being applied successfully, the user should be able to down- or upregulate neural connectivity between target regions: For instance, in the scope of drug addiction, the dorsolateral prefrontal cortex and the anterior cingulum are of primary importance, because their network regulates craving for substances. After approximately 6 to 10 training sessions (the session repetition numbers can vary from study to study), first changes can be detected: Preliminary results suggest changes in connectivity for patients suffering alcoholism, meaning that by upregulating prefrontal “will-power” regions, patients can learn how to control and decrease craving impulses stemming from deep subcortical regions such as the ACC (see also: Info Box). But research in this area is still far away from providing concrete evidence that the technique leads to stable real-life transfer and long-lasting benefits in clinical settings.
By now, the technique´s promising approach is nowhere near being easily applicable in real life, not merely a foot tap accompanying one of your favorite tunes. Mental illnesses – such as addiction – resemble complex pieces of music, and the orchestra – e.g. the neurofeedback intervention – yet has to learn how to deal with the unique intricacies of every single tune. But the magic between song and artist is definitely already in the room, as neurofeedback techniques are already aiding the recovery of certain pain, stroke or psychiatric patients. And this is all but a cheap magic trick – but solid science enabling magical milestones for future therapy.
Info Box: fMRI BCI Neurofeedback in Alcoholics
BCI – Neurofeedback can be used in alcohol addiction therapy as a means of delivering feedback of activity time courses – e.g. connectivity of the dlPFC and the ACC respectively – onto a PC screen within an fMRI scanner. This is done using real-time functional MR imaging sequences of correlations between activation of the dlPFC and the ACC target regions. Both regions play a crucial role in processing alcohol craving: The dlPFC substrate can prefrontally inhibit craving stemming from subcortical ACC regions. The goal of this pilot study was to strengthen self-control mechanisms in patients that generally suffer from a loss of reliable self-efficacy. By giving patients a tool to control alcohol craving willingly, craving should be reduced and adjacent symptoms of alcoholism such as depression, elevated anxiety levels and decreased overall well-being should be improved.
Marius Vogt is currently a Master student at the institute of psychology at Eberhard Karls University of Tübingen. He recently graduated the M.Sc. program in psychology with a thesis on self-regulation in alcohol addicted patients using a real-time fMRI – Brain Computer Interface.