Biomedical Engineering Reference
In-Depth Information
colleagues (2011) found increased lateralization toward the ipsilesional sensorimotor
regions in a patient with severe hand paresis after using a MEG- and EEG-based BCI in
combination with physiotherapy.
17.6 BCI and Behavioral Disorders
17.6.1 epilepsy and ADHD
Researchers have used neurofeedback training with various EEG measures to treat
patients with pharmacologically intractable or insufficiently tractable diseases, such
as intractable epilepsy and attention deficit hyperactivity disorder (ADHD). Epilepsy is
a severe neurological disorder that is characterized by seizures, caused by an excessive
and synchronous activity of the central nervous system (CNS). This abnormal activity
causes symptoms that vary depending on the type of epilepsy and can affect patients in
different ways. A seizure can last from few seconds to minutes, sometimes with loss of
consciousness and/or loss of muscular control, with tonic, clonic, and myoclonic muscle
spasms, or a mixture of these. The World Health Organization (WHO) estimates that
epilepsy affects at least 50 million people worldwide (Dua et al. 2006). Epilepsy can be
treated pharmacologically, but some people do not respond to any medications.
Other potential users of BCIs are ADHD patients. ADHD is a neurodevelopmental
disorder, with inattention, hyperactivity, and impulsivity (Zwi et al. 2000). The term
ADHD and the disorder is a controversial issue. The extent to which symptoms are
considered pathological varies and should be assessed in the context of the child's
developmental level. A prevalent theory links this disorder to abnormal development in
the dopaminergic and noradrenergic cortico-subcortical networks, which are important
for executive functions and the regulation of attention. Approximately 3-5% of children
are affected by ADHD, and they are usually treated with stimulants that decrease
impulsivity and hyperactivity and increase attention. Nevertheless, there is a strong
demand for nonpharmacological treatments because of several concerns about the use of
stimulant medication during development (Strehl et al. 2006).
17.6.2 neurofeedback in epilepsy and ADHD
The first clinical application was the use of slow cortical potential (SCP) regulation to
control untreatable epileptic seizures (Kotchoubey et al. 2001). As previously mentioned
(see Section 17.4.1), several studies have shown that learning to control SCPs affects the
number of ictal events in patients with drug-resistant epilepsy (mostly with secondarily
generalized seizures) (Rockstroh et al. 1993; Kotchoubey et al. 2001). A more recent study,
which included the self-regulation of SCPs in a behavioral self-management program,
confirmed that more than half of the patients involved had significant reductions in the
number of seizures (Strehl et al. 2005).
By using similar procedures, BCIs have shown good success in the treatment of children
with ADHD (Strehl et al. 2006; Fuchs et al. 2003). In these studies, although with small
samples, it was shown that it is possible to improve attention and vigilance (for a complete
review on the effects of different treatments on ADHD, refer to Toplak et al. 2008). Thus,
the mitigation of ADHD symptoms obtained with SCP self-regulation is comparable to the
