Combined use of transcranial Direct Current Stimulation and psycho-sensory stimulation in a patient with severe disorder of consciousness

The main aim of this work was to evaluate the effectiveness of the transcranial Direct Current Stimulation (tDCS) on alertness improvement in a patient in a Minimally Conscious State (MCS) by means of DOCS scale combined with a structured psycho-sensory protocol and specific individualized checklists. A further purpose was to estimate the effects of tDCS on muscle hypertonus through the Ashworth scale. Transcranial Direct Current Stimulation (tDCS) (1.5 mA, 10-second ramp, 20 minutes a day, 3 days a week, for 3 months) was performed through a two-channel intra-cephalic stimulator. Two stimulating electrodes (anodes) were applied on the left Prefrontal Cortex (PFC) and the cerebellar cortex, respectively. The cathode was positioned on the right primary motor cortex (M1). This protocol aims at activating the fronto-parietal mesocircuit. After stimulation, the patient followed a cognitive behavioural psycho-sensory stimulation training associated with physiotherapy and speech therapy sessions. The results, obtained through the systematic observation of the patient during the treatment, showed an improvement in the level of alertness, as well as an increase in the quality of the rehabilitation intervention, highlighted both by a higher DOCS score and by ad hocscales set up specifically for the patient. Although these data refer to a single subject, they seem to demonstrate the usefulness of the non-invasive brain stimulation techniques combined with rehabilitation treatment. The importance of this combination was already proposed by other authors, who reported an improvement in the sensory abilities and in the level of onsciousness in a group of individuals with a diagnosis of Vegetative State (VS) or Wakefulness Unresponsive State (UWS) by stimulating the left primary sensorimotor cortex and inhibiting the right orbito-frontal one. Furthermore, this study highlights some fundamental aspects which could be useful for the implementation of an intervention protocol addressed to patients suffering from a disorder of consciousness, by building a personalized treatment, based on patient’ s specific clinical features and not only on standardized measures. In conclusion, the outcomes of this research highlight the key role of transcranial electrical stimulation in producing improvements in patients with disorders of consciousness, especially when applied in combination with individualized and ad hoc protocols built on patient’ s clinical features.