## 3 Practical Applications of VR in CR
### Individual Semi-Inmersive Systems  
Individual semi-immersive rehabilitation combines the immersion of virtual reality technology with physical interaction in the real world. By utilizing specific hardware devices such as VR helmets, handheld controllers, or motion capture systems, it provides a training environment that lies between complete virtuality and reality. The characteristic of this technology is its ability to simulate real-life activity scenarios while allowing patients to perform various movements and cognitive tasks in a safe environment, thus promoting the remodelling and recovery of neural systems and functions. Additionally, semi-immersive rehabilitation technology can adjust the difficulty and complexity according to the patient's progress and needs, achieving personalized rehabilitation training. Compared to individual immersive virtual reality rehabilitation therapy systems, individual semi-immersive virtual reality rehabilitation therapy systems provide a balance between immersion and real-world connection, which may cause less disorientation for some patients [26] and is easier for therapists to monitor and assist [27]. It is suitable for cognitive rehabilitation treatment of patients with stroke, Parkinson's disease, Alzheimer's disease, and multiple sclerosis, among others. [PERSON] et al. (2011) [28] conducted a controlled trial in a 2011 paper, with the virtual reality system in the experimental group being a semi-immersive virtual reality system--the IREX system. The experimental environment consisted of a television monitor, camera data gloves, and virtual objects. The system included five programs with different training items, which could evaluate and train patients' visual, auditory perception, attention, and memory functions. The experiment analyzed the performance of 28 patients with cognitive impairment after stroke in different rehabilitation treatments. The researchers concluded that compared to the control group that only received computer-based treatment, the VR group that received both virtual reality training and computer-based cognitive rehabilitation could achieve greater benefits. [PERSON] et al. (2015) [29] designed the BrightBrainer comprehensive cognitive therapy system in 2015, mainly for the cognitive function rehabilitation treatment of Alzheimer's disease patients. The system consists of a computer, a dual-hand game controller, a remote clinical server, and a custom-designed comprehensive cognitive simulation library. Participants can achieve virtual reality interaction through single-hand or dual-hand operation. BrightBrainer can also customize unique rehabilitation training games according to the patient's needs and adjust them at any time based on the patient's rehabilitation status. The system has multi-sensory perception functions and can train participants' memory and decision-making ability, and improve their depression. [PERSON] et al. (2017) [30] and [PERSON] et al. (2017) [31] designed a individual semi-immersive rehabilitation treatment system for multiple sclerosis patients in a 2017 paper. [PERSON] designed Robot-Assisted Gait Training (RAGT), a walking function rehabilitation system that combines Lokomat with VR, mainly used for postoperative walking function rehabilitation of multiple sclerosis and stroke patients. Lokomat consists of a treadmill and an exoskeleton with two powered orthoses, fixed to the patient's limbs with cuffs and belts. The hip and knee joints of Lokomat are driven by linear actuators and move the orthoses in the sagittal plane during the gait cycle. The real-time movement of the patient is projected on the screen through the augmented feedback module. Through the analysis of data from a randomized controlled trial involving 40 volunteers, the researchers found that RAGT combined with VR is more effective in treating walking disability in MS patients compared to RAGT without VR. [PERSON] et al. (2017) [31] built the Virtual Reality-Based Rehabilitation (VRBR) system using a layered architecture style.