Post-stroke Aphasia

The use of transcranial direct current stimulation (tDCS) for the management of deficits developed in stroke is a relatively new type of management option. Many of the studies performed using tDCS have focused on improvements noted in hemiplegia as compared to aphasia, which is an equally disabling outcome of strokes. The results of these studies have not been conclusive and concordant with each other. In aphasia management, the majority of the studies have focused on chronic strokes. Since the use of tDCS is relatively new, the studies have not focused on a particular type of deficit or stroke. Very few studies have focused on the impact of solely using tDCS. Very few studies have focused on acute to subacute strokes. The results of the studies have, nevertheless, been encouraging. Improvements in aspects of language tested after a single session of tDCS are short-lived. There is an unmet need to probe the utility of repetitive tDCS on aspects of language function in patients who are aphasic due to acute stroke. There is also a paucity of data in the Indian scenario regarding the same.

Neurological disorders encompass a wide variety of diseases, including congenital and neurodevelopmental disorders, cerebrovascular and neurodegenerative diseases, nervous system infections, neuroimmune diseases, neuromuscular or peripheral nervous system disorders, traumatic injuries, and tumor-related neurological conditions, with diverse symptomatic manifestations. The etiology, symptoms, and disease courses of these disorders vary significantly, severely impacting human health and social development, and have become a critical global public health issue. Some neurological disorders can lead to lifelong disability or high mortality rates, while others remain poorly understood, lacking effective treatments or cures. Post-stroke aphasia (PSA) is an acquired language impairment caused by ischemic or hemorrhagic injuries to the central nervous system. Its clinical manifestations are diverse, potentially affecting spontaneous speech, auditory comprehension, repetition, naming, reading, and writing abilities, among other aspects. Statistics indicate that over 16 million people worldwide suffer from stroke each year, with approximately 38% of survivors experiencing aphasia. The prognosis for this condition is concerning, as more than 40% of patients still exhibit significant language impairments one year after the stroke, with some even facing lifelong effects. The large patient population, significant communication barriers, and poor prognosis severely diminish patients' quality of life, significantly increasing their risk of emotional disorders such as depression and social isolation. This poses a substantial challenge to family caregiving and public health systems. Therefore, the development of non-invasive and effective novel therapeutic approaches holds substantial scientific and societal importance. Temporal interference stimulation (TI) technology represents a breakthrough in achieving non-invasive deep brain stimulation. This technology is based on the interference phenomenon, utilizing two pairs of surface electrodes to simultaneously apply sinusoidal wave stimuli at 2 kHz and 2.01 kHz. Two cortical regions are exposed to electric fields of 2 kHz or 2.01 kHz, and an interference electric field is generated in the brain region where these two fields overlap, with its envelope oscillating at 10 Hz. This technology has already been applied in the treatment of conditions such as depression, Parkinson's disease, and disorders of consciousness. The primary objective of this study is to explore the effects of TI intervention on deep brain regions, particularly on motor and non-motor related brain networks and functions in patients with neurological disorders, especially post-stroke aphasia. This research aims to provide a potential new approach for improving the clinical symptoms of these patients.

The aim of the trial is to determine whether 75Hz transcranial alternating current stimulation (tACS) synchronized with therapeutic linguistic tasks is an effective form of therapy for post-stroke aphasia.

The Effect of Low-Level Light Therapy on the Electrical Activity of the Brain in Stroke Patients