Rebalancing the brain with non-invasive brain stimulation during stroke recovery

Stroke is a leading cause of neurological impairments in motor functions,
attention, or language. In the Netherlands each year 40.000 people suffer a
stroke and approximately 0.8% of the general population in the Netherlands
lives with the consequences of stroke. Hemispatial neglect is a common
consequence of unilateral brain damage, occurring in approximately 30% of
stroke-affected individuals, with the prevalence increasing substantially if
the right hemisphere is affected (Corbetta, Kincade, Lewis, Snyder, & Sapir,
2005). Individuals with neglect syndrome demonstrate failure to attend or
respond to items in their contralateral side of space. Neglect has been
demonstrated as an important prognostic component for stroke recovery, with
cognitive impairment up to three times more common for individuals suffering
from severe neglect, suggesting a need for early rehabilitation of neglect
symptoms in stroke-affected individuals (Johansson, 2011). Current therapeutic
interventions try to reduce stroke-related symptoms by pharmacological,
physical, and occupational therapy. Over the last twenty years, cognitive
neuroscience has gained key insights into the workings of the brain.
Implementing this knowledge into stroke rehabilitation offers the potential to
enhance effectiveness of treatment and thus improves patients* quality of life
and reduces the burden on social health care systems.

Investigating the effectiveness of tCS on the recovery of neglect in sub-acute
ischemic stroke patients suffering from neglect to complement conventional
treatment

The current study will use tCS as a potential neglect rehabilitation treatment.
Every patient will first receive a baseline measurement to reliably assess
his/her performance level in a neuropsychological test battery. After that, the
experimental treatment will start. The treatment will exist of 2 sessions of
non-invasive neuromodulation for every patient: tCS treatment and placebo
treatment. At the beginning of each session, patients will perform a
neuropsychological task battery together with a computerized computerised
Visual Detection Task (CVDT). Then they will receive real or placebo tCS whilst
performing the CVDT. After the stimulation, there will be 3 post measurements
consisting of neuropsychological and computerized tasks, namely right after
stimulation, 20 minutes after stimulation and 40 minutes after stimulation. One
day later, they will do the second treatment session, where they again receive
either real of placebo tC stimulation. The order of the sessions will be
counterbalanced, where one half of the patients will start with the tCS
treatment and the other half with the placebo treatment. Patients will thus
have three sessions. In one session, the severity of their neglect is
determined with the help of a neuropsychological test battery. The first
session will last no longer than 1 hour. The other two sessions will both last
about 2 hours. The total time investment is thus 5 hours.

The participants may potentially have direct benefit from the project.
All patients will be offered the standard revalidation programme in the
rehabilitation centre.

The current study will use tCS as a potential neglect rehabilitation treatment.
Every patient will first receive a baseline measurement to reliably assess
his/her performance level in a neuropsychological test battery. After that, the
experimental treatment will start. The treatment will exist of 2 sessions of
non-invasive neuromodulation for every patient: tCS treatment and placebo
treatment. At the beginning of each session, patients will perform a
neuropsychological task battery together with a computerized computerised
Visual Detection Task (CVDT). Then they will receive real or placebo tCS whilst
performing the CVDT. After the stimulation, there will be 3 post measurements
consisting of neuropsychological and computerized tasks, namely right after
stimulation, 20 minutes after stimulation and 40 minutes after stimulation. One
day later, they will do the second treatment session, where they again receive
either real of placebo tC stimulation. The order of the sessions will be
counterbalanced, where one half of the patients will start with the tCS
treatment and the other half with the placebo treatment. Patients will thus
have three sessions. In one session, the severity of their neglect is
determined with the help of a neuropsychological test battery. The first
session will last no longer than 1 hour. The other two sessions will both last
about 2 hours. The total time investment is thus 5 hours.
The occurrence of any negative consequences of the tCS intervention on stroke
recovery has never been reported in any clinical tCS study so far.