## 1 Introduction  
Stroke is a sudden life-threatening neurological emergency, characterized by impaired perfusion in the central nervous system, which leads to brain tissue injury. Based on etiology, there are two types of impaired perfusion in blood vessels: ischemic stroke, when there is occlusion in cerebral arteries, or cerebral venous and hemorrhagic, when there is a leakage of blood vessels and bleeding [1]. Regardless of the cause, stroke is the second most common cause of death worldwide and the third cause of disability and death combined [2]. In Australia, the US, and Europe, stroke is the leading cause of disability among adults [3, 4]. One of the main complications of stroke is motor impairment of varying degrees, from limitations to losses of muscle control, movement, or mobility. It is estimated that at the onset of stroke, approximately 80% of patients have a loss of muscle control [5]. Immediately after the acute phase of a stroke, two-thirds of survivors have mobility deficits, and 6 months after the stroke, more than 30% of patients still struggle with motor disability. Another complication occurring in about 25-30% of individuals with stroke, predominantly right-hemisphere stroke, is unilateral spatial neglect (USN) syndrome [6; 7]. Hemineglect syndrome, also known as spatial neglect syndrome or unilateral spatial neglect syndrome, is a neuropsychological disorder of spatial awareness, which is contralateral to brain lesions. Patients pay little or insufficient attention to stimuli presented on the side opposite to the injured cerebral hemisphere. They are unable to report, respond, or orient toward these stimuli [8]. Unilateral spatial neglect is a risk factor associated with poor outcomes in recovery. USN can affect a person's ability to perform everyday activities. They may omit food from the contralateral side of the plate and wash only the ipsilesional parts of the body. As a result, they become functionally dependent. Individuals also have an increased risk of falls and may require longer hospitalization [9; 10; 11]. One way to treat the above-mentioned complications after a stroke is rehabilitation. It aims to recover damaged neuronal connections. This results in the restoration of impaired functional abilities, which offers the possibility of improving the quality of life for those struggling with complications, which is why every stroke patient should have access to both early rehabilitation in neurological rehabilitation units and long-term rehabilitation on an outpatient or home basis. The demand for stroke rehabilitation services is still increasing because of the current trends; for example, forecasts for Europe from 2017 to 2047 predict a 17% decrease in stroke mortality but a 27% increase in stroke prevalence [4]. If there are no contraindications, guidelines assume the possibility of using virtual reality (VR) as an alternative method to traditional therapy [12]. Studies such as [13; 14; 15; 16; 17] present the use of virtual reality for patient rehabilitation. Initially, these applications were aimed at children and teenagers, as they encouraged the youngest to exercise. In particular, they were concerned with the rehabilitation of the musculoskeletal system and also with speech training or pain reduction [18]. Later, VR appeared in applications aimed at adults. VR applications have been used in the treatment/rehabilitation of orthopedic conditions (such as ankle sprains and shoulder pain and impingement) [19], neurological rehabilitation [20], the general rehabilitation of the upper body, particularly the upper extremities [21; 22], Parkinson's disease, Alzheimer's disease, and eating disorders [23]. Many studies show the effectiveness of VR in neurological rehabilitation [24; 25; 26; 27], including post-stroke rehabilitation [15; 28; 26]. The use of virtual reality in general rehabilitation has many advantages [29].