Electrophysiological measures of efficacy in neurofeedback rehabilitation of aphasic patients

Abstract

Objective. The following study investigated the effects, measured by a quantitative analysis of the cerebral frequencies (qEEG) of a clinical protocol consisting of 20 neurofeedback sessions on patients affected by aphasia divided in three groups: one experimental group who received real neurofeedback session, a placebo group and a natural history group.

Materials and methods. 30 patients have been randomly divided in three groups (N = 10): one experimental group who received real neurofeedback sessions (Neurofeedback Verum, NFV), a placebo group who observed registered videos instead of real neurofeedback recordings (Neurofeedback Placebo, NFP) and a natural history group who didn’t receive any kind treatment (Natural History, NH). The neurofeedback sessions, 20 minutes long and two times per week, were based on the increase of alpha (8-12 Hz) as well as beta (12-20 Hz) frequencies. All patients were tested with qEEG before the beginning of the therapy (TEST) and after the end of the therapy (RETEST).

Results. An increase of the frequencies beta 1 (12-20 Hz) in T5 and beta 2 (16-20 Hz) in T3 has been observed only in the group NFV while no change in the qEEG has been observed in the placebo (NFP) or natural history (NH) group.

Discussions. The increase in beta 1 and 2 frequencies in the left temporal lobe only in the experimental group NFV indicates a possible influence of the treatment on the damaged areas after the stroke in aphasic patients. Indeed, it has been shown how the beta rhythm, in particular beta 2, is linked to the cognitive-attentive cerebral level but also to the elaboration of language. Furthermore, this frequency band is a measure of the brain damage in aphasic patients where is less represented in the central and posterior areas of the left hemisphere (thus including the temporal electrodes).

Conclusions. Even though neurofeedback is used in the treatment of different neuropsychiatric disorders, there are still no systematic studies on this technique, in particular in aphasic patients. The present study represents the first step in standardizing a clinical neurofeedback protocol and collect objective data from qEEG in experimental as well as placebo groups.