Thanks to the exponential technological advancements we've seen in the past years, virtual reality in healthcare and telerehabilitation has become much more common in patients' daily lives that require long-term medical attention.
Currently, healthcare centers and hospitals can adopt both 2D and 3D rehabilitation technologies. The first one uses a two-dimensional environment and the second one a three-dimensional context in the physical and cognitive recovery process. In other words, the hardware and software used differ significantly in motor and cognitive-behavioral recovery.
In this article, you will find why 3D digital therapy is more efficient than 2D therapy in almost every aspect. We explain the differences, pros and cons, present practical cases conducted by researchers and provide even more information.
What is rehabilitation through 2D and 3D digital therapy?
Despite the challenge of homogenizing healthcare processes and making the system more accessible, the digital transformation in healthcare, innovation and research, and the focus on personalized services are topics of great interest to the medical and scientific communities.
Although there is a world of difference between 2D and 3D rehabilitation, both are digital therapies, meaning non-conventional. The first stands out for flat visualizations because they only have two dimensions (height and length), while the second also has the characteristic of depth (Z-axis), which gives it a greater degree of realism.
2D digital therapy
In general terms, 2D rehabilitation involves performing rehabilitation exercises in front of a monitor, often using a console like Xbox (with a Kinect sensor). It is characterized by:
Simplicity: 2D environments are simpler and less immersive than 3D environments. They can be appropriate for basic rehabilitation exercises and activities.
Accessibility: 2D rehabilitation solutions and programs are often more accessible and easier to utilize for people with limited technological expertise, but they are less effective
Limited range: 2D environments may have a more limited range in terms of simulating real-world situations and immersive experiences.
3D Digital Therapy
On the other hand, 3D rehabilitation, or immersive virtual reality, is mainly performed with virtual goggles and is characterized by:
Realism and immersion: 3D environments offer a more realistic and immersive experience, which can be more beneficial for complete rehabilitation.
Spatial interaction: The 3D environments can allow interaction with more degrees of freedom of movement and spatial recognition, crucial for motor and cognitive rehabilitation where spatial perception and/or motor exploration is relevant.
Variety of situations: 3D environments can simulate a wide range of situations and scenarios, making them beneficial for training skills in lifelike environments.
In addition to the features mentioned above, immersive virtual reality improves exercise performance and execution, enables intuitive and functional movements, expands ranges of motion, provides unique real-time hand and finger interaction, and promotes fine and gross motor recovery.
Scientific Evidence of Virtual Reality in Neurorehabilitation
Interest in virtual reality has grown exponentially in recent decades, with over 1500 articles published on the subject between 1995 and today, including more than 200 randomized controlled clinical trials, as indicated by the research titled “Virtual reality for neurorehabilitation: A bibliometric analysis of knowledge structure and theme trends.”
The annual number of publications has progressively increased over the last three decades, reaching a maximum peak of 276 publications in 2021, and its popularity is expected to continue rising in the upcoming future.
According to the article “Modulation of cortical activity in 2D versus 3D virtual reality environments: An EEG study”, immersive virtual reality generates greater attention and better perceptual-motor performance than 2D. The possible causes are:
Blocking of the exterior (physical isolation of the goggle)
Greater stereoscopic effect
Larger visual range
Mobile visual perspective
Increased sense of self-presence
Increased sense of environmental reality
Greater sense of interaction
In addition, in this same scientific study, at the neurophysiological level using electroencephalography, they demonstrate that virtual reality with 3D immersion versus semi or non-immersive VR produces:
Increased front-medial theta activation, associated with better performance in spatial route learning
Increased error monitoring
Greater success in perceptual-motor tasks
More efficient allocation of brain resources to cognitive, motor, and behavioral aspects of the brain
Generically, the improvement of balance and cognitive-behavioral functions using a VR-based protocol has been documented in several studies.
Specifically in “Improvement in balance using a virtual reality-based stepping exercise: a randomized controlled trial involving individuals with chronic stroke”, that reported on the effectiveness and usability of a VR-based intervention compared with conventional physical therapy in the recovery of balance in patients with chronic stroke.
The study by Cikajlo and Peterlin Potisk entitled “Advantages of using 3D virtual reality based training in persons with Parkinson's disease: a parallel study” clarifies that, regardless of the visual technology used in their study, participants improved upper extremity fine motor skills in terms of clinical tests and kinematic measures.
Some of the positive results were likely due to the increased motivation of the participants. Those who used the 3D visual equipment increased their motivation and interest scores, which resulted in faster and more efficient functional performance, apparently due to greater visual perception.
The latter was not possible with the 2D equipment and was presumably because they gradually lost interest and consequently put less effort into performing the task at hand.