Universiteit Leiden

The Back-Fed Brain

The Back-Fed Brain

Neurofeedback is a tested science, aiding in the treatment of different neural disorders. However, systems meant for the general public and used outside labs and clinics like the one talked about here often fall below expectations.

Recently I tried the NeuroSky Force Trainer II: Hologram Experience game, an EEG (electroencephalography) headset and iPad app which is supposed to help you “Unlock the Powers of the Force”. Quarter-sized electrodes pressed against my forehead and behind my ears, I sat staring at the Trainer for over an hour trying hard to increase my brain’s beta frequencies, disappointed.

 At SNAP GmbH, the company where I work on Brain-computer interface systems, I deal daily with EEG, and I know EEG neurofeedback has a solid basis of correlational evidence. Spectral analysis (a fancy way to say looking at the different rhythms of the brain) and its feedback is widely used in the diagnosis and even treatment of different diseases such as epilepsy, schizophrenia, and ADHD.

So why was my experience a disappointment? I faced the hologram of an orb, which was created by the superposition of the reflections on three perpendicular tilted clear plastics illuminated by the iPad running the Force Trainer II app. The game asked me to concentrate to lift the orb – a Marksman-H combat Remote similar to those with which Luke Skywalker first trains in Star Wars: A New Hope – but as much as I tried, the orb did not follow my intentions; it seemed to move randomly.

What the game was attempting, aside from the science fiction of Star Wars, is called neurofeedback training. In EEG systems this technique calculates the rhythms of clusters of neurons firing in the brain by measuring the cortical potentials and deconstructing the time-locked signal into different frequencies, or rhythms, and display them on a monitor. This allows the user to see what mental states increase which bandwidths, granting an overview of an otherwise not-perceived mental action. There are many studied modalities of EEG neurofeedback training but one of the most used (and the one listed in the oversimplified documentation of the Force Trainer) aims to train concentration. Studies have shown that a cortical rhythm of 12-20Hz – also called SMR (Sensorimotor rhythm) at the lower end of the beta band – is dependent on concentration or focus. In fact, children with ADHD have been shown to benefit from neurofeedback training and learning to increase their SMR.

The pamphlet which came with the game had the theory right, concentrating should result in a measurable increase in my beta frequencies. The problem was perhaps in the execution. Reported testing and clinical neurofeedback training likely occur in very controlled environments, using multi-thousand-dollar equipment, and sometimes even a magnetically shielded room for pristine EEG acquisition. My set-up consisted of a headset of less than $100 and an iPad in an unshielded office room. It seems the allure of controlling things with your mind, using The Force or whatever, has jumped the gun in the private sector. There is only a small (growing) body of work suggesting that neurofeedback training can be useful to healthy individuals at home. And some companies have taken the theory of neurofeedback training and run with it, releasing products such as the Neurosky Force Trainer.

The science of neurofeedback may sound like science-fiction, but the research is clear. It is just not yet available to the public. However, with the advances in headset design, artefact filtering, and a deeper understanding of how the brain works, it won’t be long until people can have access and use of neurofeedback EEG devices. Until then, if presented with a $100 device that promises to work as well as a $5000 one, remember the words of Admiral Akbar, “It’s a trap!”.

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