Neural interfacing non-invasive brain stimulation with NIRS-EEG joint imaging for closed-loop control of neuroenergetics in ischemic stroke

Stroke can be defined as a sudden onset of neurological deficits caused by a focal injury to the central nervous system from a vascular cause. In ischemic stroke (∼87% of all strokes) and transient ischemic attack (TIA), the blood vessel carrying blood to the brain is blocked causing deficit in the glucose supply - the main energy source. Here, neurovascular coupling (NVC) mechanism links neural activity with the corresponding blood flow that supplies glucose and oxygen for neuronal energy. Brain accounts for about 25% of total glucose consumption while being 2% of the total body weight. Therefore, a deficit in glucose supply can quickly change brain's energy supply chain that can be transient (in TIA) or longer lasting (in stroke, vascular dementia). Here, implications of the failure of brain's energy supply chain can be dysfunctional brain networks in cerebrovascular diseases. Using near-infrared spectroscopy (NIRS) in conjunction with electroencephalography (EEG), a non-invasive, real-time and point of care method to monitor the neuroenergetic status of the cortical gray matter is proposed. Furthermore, we propose that NIRS-EEG joint-imaging can be used to dose non-invasive brain stimulation (NIBS) - transcranial direct current stimulation (tDCS) and photobiomodulation - which may be able to provide therapeutic options for patients with energetic insufficiency by modulating the cortical neural activity and hemodynamics.