Introduction
For human beings, knowing the objects’ location and the ability to navigate have always been crucial for survival and performing the majority of activities. The acquisition, storage, utilisation, organisation, and revision of individual knowledge about the environment are closely connected with spatial cognition, a complex and multidimensional process of the environment’s perception that comprises numerical, social, linguistic, and other domains. According to a consensus, vision has a crucial role in spatial cognition as it traditionally provides the most reliable and accurate information concerning the external world’s properties (Cappagli & Gori, 2019). At the same time, not all researchers share a common opinion related to the significance of vision for the environment’s accurate perception. Their claims are supported by the ability of blind and neglect people to receive experience and perform cognitive tasks with the use of non-vision modalities. That is why the purpose of the paper is to critically evaluate the role of visual experiences for spatial cognition in blind and neglect people.
Spatial Cognition
The idea and conceptualisation of space have always been a subject of philosophers’ continuous debates. Traditionally, they are determined by contrast between the definition of space derived from physics and mathematics and its personal understanding. Ernst Mach and Hermann von Helmholtzand were the first cognitive scientists who suggested that both objective (physical) and subjective (intuitive) space should be considered (Tommasi & Laeng, 2012). The investigation of space from the position of cognitive science and psychology has led to the existence of research dedicated to spatial cognition, defined as mental processes and representations evolved in living organisms in order to cope with the physical dimension of space.
As a matter of fact, encoding locations and computing relationships between them may be regarded as highly essential for any navigating species’ survival. As Lee (2017) supposes, spatial cognition is one of the oldest cognitive abilities of high-level organisms to have evolved. It is based on the properties of spatiality that include size, shape, location, direction, connectivity, dimensionality, hierarchy, overlap and many others (Montello & Raubal, 2013). As humans’ essential ability, spatial processing refers to the sensing of all spatial aspects and their integration in the environment. It comprises both mentally constructed inner mental representations and external multisensory information (Cona & Scarpazza, 2019). The study of spatial behaviour and cognitive processes began in the 1940s when Tolman’s experiments indicated animals’ ability to compute directions and locations irrespective of their previous movements to reach the goal (Lee, 2017). However, human spatial cognition is a more complex process in which more cognitive processes are involved.
For human beings, knowing the objects’ location and the ability to navigate are crucial for performing most activities. At the same time, “the nature of an organism’s plastic spatial relationship to the environment is also a defining quality of its identity” (Proulx et al., 2016, p. 2). For their social and physical survival, people rarely remain stable and travel to multiple locations in order to exercise, meet with friends and family members and perform daily tasks. Therefore, all movements require the environment’s accurate spatial representation for navigation with the use of a cognitive map (Epstein et al., 2017). Thus, a combination of cognitive skills, including object recognition, localisation and obstacle avoidance, is required for real-world navigation.
In addition, allocentrism and egocentrism refer to spatial reference frames to represent objects’ locations. Thus, an allocentric reference frame defines “the location of something else is in reference to yet another object, independent of oneself”, while in an egocentric frame, a person denotes something else’s location in reference to himself (Proulx et al., 2016, p. 5). At the same time, spatial cognition is essential not only for navigation and orientation in the environment but for the formation of the individual’s personality and self-perception as well (Vasilyeva & Lourenco, 2012). That is why the understanding of spatial cognition in patients with visual impairment and neglect is essential to develop the most appropriate strategies for their rehabilitation.
Role of Vision in Spatial Cognition
Visual experience has a crucial role in guiding the development of spatial competence. Vision takes advantages “respect to other senses in encoding spatial information because it ensures the simultaneous perception of multiple stimuli in the environment despite the apparent motion of the array on the retina during locomotion enabling us to extract more invariant spatial properties from the surrounding layout” (Cappagli & Gori, 2019, par. 3). The tendency of sighted people to organise space-related information in accordance with their visual frame of reference is supported by psychophysical data that indicate the occurrence of sensorial conflict when touch and audition are biased by visuospatial information presented simultaneously. The fundamental significance of the visual feedback for spatial learning and the construction of visuospatial and auditory cortical maps is confirmed by neurophysiological data as well. Thus, vision traditionally provides the most reliable and accurate information concerning the external world’s spatial properties – thus, it dominates spatial perception (Cappagli & Gori, 2019). Therefore, the spatial cognition of blind and neglect individuals is supposed to be substantially limited.
However, there is a controversial opinion that argues the importance of vision for spatial cognition. According to Hutmacher (2019), vision is more investigated in comparison with other modalities due to the convenience of its examination with the use of modern technologies. In addition, the dominance of vision is frequently determined culturally and socially, and the senses’ universal hierarchy does not exist. In this case, it is impossible to state that blind or neglect people have limited abilities in their perception of the environment with the help of other modalities.
Spatial Cognition in Blind and Neglect People
There are two main theories that explain spatial cognition in blind people and the related role of vision. The first one is the inefficiency or cumulative model that states that non-visual sensing is less accurate for spatial cognition in comparison with direct visual perception. Therefore, blind people, especially congenitally blind individuals, will always be limited in spatial abilities, and their cognitive experience will be continuously at a deficit without an opportunity for improvement (Giudice, 2018). This model is supported by the experiment of Maćesić-Petrović, Vučinić and Eškirović (2010), who aimed to evaluate the cognitive development of children with visual impairments. As both congenitally blind and children with low vision were involved, it was impossible to receive homogeneous results. In addition, according to Creem-Regehr et al. (2021), “people with visual impairment often rely on their residual vision when interacting with their spatial environments” (p. 1). This means that individuals who partially lose their vision during life still heavily rely on this modality.
The perception of space in the case when blindness emerges at birth cannot be regarded as unaffected by the inability to see. Pasqualotto and Proulx (2012) state that in the case of congenital blindness, non-visual modalities cannot fully compensate for the lack of visual experience. In addition, developmental visual experience is essential for the formation and appropriate development of multisensory neurons responsible for spatial tasks. At the same time, another theory, the difference, or convergent model, suggests that blind people are able to receive visual experience through non-visual modalities, and their disparity may decrease (Schinazi et al., 2016). Congenitally blind people outperform sighted in superior auditory and tactile modalities on the basis of which they reconstruct the environment using spatial memory. In addition, they substantially outperform blindfolded sighted people in their ability to estimate direction and distance, sketch mapping and reconstruct routes. Nevertheless, in the present day, it is impossible to estimate the potential of non-visual modalities to replace vision for spatial cognition in blind people due to the absence of technologies and accurate methods.
Role of Neglect Patients
Another issue that may impact a person’s ability to perceive space is visual neglect. Ting et al. (2011) define visual neglect as “a common, yet frequently overlooked, neurological disorder following stroke characterized by a deficit in attention and appreciation of stimuli on the contralesional side of the body” due to the outer world’s disrupted internalized representation (p. 114). There is no common test to assess neglect due to the existence of several types, including sensory and motor neglect, allocentric neglect and egocentric neglect (Lunven & Bartolomeo, 2017). Neglect patients traditionally have difficulties maintaining an internal map’s left side or obtaining other spatial knowledge related to the environments properties, such as objects, bodies, or reference frames. In the case of profound visual neglect, a person is unaware of other people and large object in peripersonal space. Neglect may affect personal space as well when a patient does not acknowledge his own contralesional body parts.
In other words, people with visual neglect cannot see a part of an image partially or totally depending on what side of their vision is affected. It goes without saying that the spatial cognition of neglect people is considerably limited by visual impairment. First of all, visual neglect leads to altered vestibular input substantially impacts a patient’s ability to navigate as navigation requires the assessment of three-dimensional space (Bigelow & Agrawal, 2015). Moreover, neglect patients lose their ability to orient as it is determined by the objects of space as the cognitive map’s landmarks. Parallel visual pathways segregate object and spatial information into distinct streams for temporal cortical regions before serving memory processes and localization in hippocampus (Kravitz et al., 2011). Visual neglect limits the integration of spatial and precise object information to encode the relationships between objects and self in space essential for memory processes and navigation. In addition, neglect cannot provide an accurate perception of three regions of space, including personal, peripersonal, and far space. In addition, neglect people demonstrate a considerable impairment of spatial memory connected with vision modalities and spatial location.
Thus, similar to people with visual impairment, neglect patients are forced to switch to non-visual modalities to perceive the environment. However, in this case, this switch is more challenging as the use of other senses cannot be perfectly developed in people who become visually neglected after the stroke. According to difference model, blind people demonstrate superior tactile and auditory modalities that contribute to the development of their spatial cognition. In addition, they may estimate directions and reconstruct routes without relying on visual modalities (Schinazi et al., 2016). However, their use for spatial cognition is possible in the case of congenitally blind people whose blindness were emerged at birth. While sighted and late-blind people code space in environmental-centered external coordinates, congenitally-blind people use observer-centered internal coordinates (Dolk et al., 2013). Neglect patients who face visual impairment accidentally cannot adapt to a new perception of space easily. Thus, for neglect patients, visual experience is immeasurably essential.
Rehabilitation of Neglect Patients with the Use of Virtual Reality and Video Games
In recent decades, video games and virtual reality have become highly accessible and effective tools in the rehabilitation of neglect patients after experiencing a stroke. In general, affected modalities may be developed on the basis of neuroplasticity that may be defined as the human brain’s ability to strengthen neural connections through constantly repeating tasks. This claim is supported by Borghese et al. (2013) who state that although the underlying mechanisms of brain rehabilitation remain unclear, the process of rehabilitation with the use of virtual reality and video games is based on multisensory integration along with spatial remapping.
Used as an additional therapy in combination with traditional ones, virtual reality provides patients with sensory stimulation, real-time feedback during task performing and an immersive environment (Pedroli et al., 2015). In addition, it allows patients to interact with a recreated environment within medical facilities in a controlled and completely safe way that cannot be guaranteed by the outer world. In virtual reality, patients may interact with nearby environmental properties in three dimensions. For instance, Cipresso, et al. (2014) address the development of virtual reality that includes a two-stored house with several rooms and a garden to facilitate patients’ orientation in the outer world. In addition, neglect patients cope with everyday tasks more efficiently if they regularly practice them through virtual reality. For instance, as orienting and navigation are closely connected with spatial memory, this memory may be developed in the safe environment before applying it into the reality.
The efficiency of the use of virtual reality and games is supported by the research of Tobler-Ammann et al. (2017). Scientists examined the influence of exergames based on therapeutic principles on patients with visual neglect. According to the study’s results, the rehabilitation of neglect patients using video games and virtual reality may be characterized by the absence of adverse effects and high adherence. In addition, findings indicate that exergames have the potential to cause substantial improvement in patients’ spatial exploration and cognitive skills.
At the same time, the use of virtual reality may help specialists to understand the processes of spatial cognition. According to recent research, including the study of Hougaard et al. (2021), eye tracking and virtual reality may be used to assess spatial neglect’s particular sub-types as patients after stroke are not readily available for conventional assessments. This method will not only help develop more sensitive diagnostics of neglect but assess special cognition of blind individuals for its comparison with the cognition of sighted people for future research. Nevertheless, it is clear that the connection between vision and non-visual modalities helps patients in its rehabilitation as it stimulates mental processes. For instance, in video games and virtual reality, eye-to-hand coordination is necessary, especially when tasks require attention or present everyday reality.
In turn, video games have already been used as a common tool for the rehabilitation of patients with visual neglect due to their potential to engage and motivate users. One of the major benefits of this therapy is the accessibility of video games that may be played both in the hospital and at home. These opportunities are particularly beneficial in the current pandemic-related conditions. During video gaming, “the patient is guided to explore his neglected hemispace by a set of specifically designed games that ask him to reach targets, with an increasing level of difficulties” (Mainetti et al., 2013, p. 97). Auditory and visual cues, targets and distractors, scenarios’ controlled randomization, background music and a reward system contribute to making the process of rehabilitation more attractive and ensuring prolonged intensive treatment (Borghese et al., 2013). Although the mechanisms of brain reorganization during rehabilitation that involved video games remain unclear, they may ground on multisensory integration and near/far spatial remapping. In any case, the use of virtual reality and video games are designated to restore patients’ visual abilities as its significance for their special cognition cannot be replaced with non-visual modalities to the fullest extent.
Conclusion
In general, due to the absence of reliable technologies and accurate methods, in the present day, it is impossible to estimate the potential of non-visual modalities to replace vision for spatial cognition in blind people. In other words, although tactile and auditory modalities help congenitally blind people to perceive the environment and navigate, their spatial cognition and the cognition of sighted people cannot be accurately compared. At the same time, according to multiple research, vision remains to be a highly essential source of cognitive experience. The tendency of sighted people to organise space-related information in accordance with their visual frame of reference is supported by psychophysical data. Vision provides the most reliable information about the outer world and contributes to the formation and appropriate development of multisensory neurons responsible for spatial tasks.
According to multiple scientific evidence, the absence of visual experience limits the cognitive capacities of blind people even if their non-vision modalities are highly developing for spatial memory, distance assessment and navigation. However, although congenitally blind individuals who have blindness emerged at birth develop other non-vision modalities for spatial cognition, partly blind people still rely on residual vision as the most significant source of information and experience. The visual experience is highly important for patients with visual neglect due to stroke. Its importance is justified by the use of virtual reality and video games during rehabilitation as it participates in the stimulation of neglected hemispace to provide appropriate health outcomes. In general, video games and virtual reality may be regarded as highly efficient tools for rehabilitation and the development of efficient treatment techniques in the future.
References
Bigelow, R. T., & Agrawal, Y. (2015). Vestibular involvement in cognition: Visuospatial ability, attention, executive function, and memory. Journal of Vestibular Research, 25(2), 73-89.
Borghese, N. A., Bottini, G., & Sedda, A. (2013). Videogame based neglect rehabilitation: A role for spatial remapping and multisensory integration? Frontiers in Human Neuroscience, 7(116), 1-3. Web.
Cappagli, G., & Gori, M. (2019). The role of vision on spatial competence. IntechOpen. Web.
Cipresso, P., Serino, S., Pedroli, E., Gaggioli, A., & Riva, G. (2014). A virtual reality platform for assessment and rehabilitation of neglect using a Kinect. Studies in Health Technology and Informatics, 66, 8. Web.
Cona, G., & Scarpazza, C. (2019). Where is the “where” in the brain? A meta-analysis of neuroimaging studies on spatial cognition. Human Brain Mapping, 40, 1867-1886. Web.
Creem-Regehr, S. H., Barhorst-Cates, E. M., Tarampi, M. R., Rand, K. M., & Legge, G. E. (2021). How can basic research on spatial cognition enhance the visual accessibility of architecture for people with low vision? Cognitive Research, 6(3), 1-18. Web.
Dolk, T., Liepelt, R., Prinz, W., & Fiehler, K. (2013). Visual experience determines the use of external reference frames in joint action control. PLoS One, 8(3), 1-8. Web.
Epstein, R. A., Patai, E. Z., Julian, J. B., & Spiers, H. J. (2017). The cognitive map in humans: Spatial navigation and beyond. Nature Neuroscience, 20(11), 1504-1513. Web.
Giudice, N. A. (2018). Navigating without vision: Principles of blind spatial cognition. In D. R. Montello (Ed.) Handbook of behavioral and cognitive geography (pp. 260–288). Edward Elgar Publishing.
Hougaard, B. I., Knoche, H., Jensen, J., & Evald, L. (2021). Spatial neglect midline diagnostics from virtual reality and eye tracking in a free-viewing environment. Frontiers in Psychology, 12(742445), 1-13. Web.
Hutmacher, F. (2019). Why is there so much more research on vision than on any other sensory modality? Frontiers in Psychology, 10(2246), 1-12. Web.
Kravitz, D. J., Saleem, K. S., Baker, C. I., & Mishkin, M. (2011). A new neural framework for visuospatial processing. Nature Reviews Neuroscience, 12(4), 217-230. Web.
Lee, S. A. (2017). The boundary-based view of spatial cognition: A synthesis. Current Opinion in Behavioral Sciences, 16, 58-65.
Lunven, M., & Bartolomeo, P. (2017). Attention and spatial cognition: Neural and anatomical substrates of visual neglect. Annals of Physical and Rehabilitation Medicine, 60(3), 124-129. Web.
Maćesić-Petrović, D., Vučinić, V., & Eškirović, B. (2010). Cognitive development of the children with visual impairment and special educational treatment. Procedia Social and Behavioral Sciences, 5, 157-162.
Mainetti, R., Sedda, A., Ronchetti, M., Bottini, G., & Borghese, N. A. (2013). Duckneglect: Video-games based neglect rehabilitation. Technology and Health Care, 21(2), 97-111. Web.
Montello, D. R., & Raubal, M. (2013). Functions and applications of spatial cognition. In D. Waller & L. Nadel (Eds.) Handbook of spatial cognition (pp. 249-264). Washington, DC: American Psychological Association.
Pasqualotto, A., & Proulx, M. J. (2012). The role of visual experience for the neural basis of spatial cognition. Neuroscience & Biobehavioral Reviews, 36(4), 1179-1187. Web.
Pedroli, E., Serino, S., Cipresso, P., Pallavicini, F., & Riva, G. (2015). Assessment and rehabilitation of neglect using virtual reality: A systematic review. Frontiers in Behavioral Neuroscience, 9(226), 1-15. Web.
Proulx, M. J., Todorov, O. S., Aiken, A. T., & de Sousa, A. A. (2016). Where am I? Who am I? The relation between spatial cognition, social cognition and individual differences in the built environment. Frontiers in Psychology, 7(64), 1-23. Web.
Schinazi, V. R., Thrash, T., & Chebat, D-. R. (2016). Spatial navigation by congenitally blind individuals. Wiley Interdisciplinary Reviews: Cognitive Science, 7(1), 37-58. Web.
Ting, D. S., Pollock, A., Dutton, G. N., Doubal, F. N., Ting, D. S., Thompson, M., & Dhillon, B. (2011). Visual neglect following stroke: Current concepts and future focus. Survey of Ophthalmology, 56(2), 114-134. Web.
Tobler-Ammann, B. C., Surer, E., de Bruin, E. D., Rabuffetti, M., Borghese, N. A., Mainetti, R., Pirovano, M., Wittwer, L., & Knols, R. H. (2017). Exergames encouraging exploration of hemineglected space in stroke patients with visuospatial neglect: A feasibility study. JMIR Serious Games, 5(3), 1-18. Web.
Tommasi, L., & Laeng, B. (2012). Psychology of spatial cognition. Wiley Interdisciplinary Reviews: Cognitive Science, 3, 565-580. Web.
Vasilyeva, M., & Lourenco, S. F. (2012). Development of spatial cognition. Wiley Interdisciplinary Reviews: Cognitive Science, 3, 349-362. Web.