Name: Video: Performing a Virtual Spatial Navigation Task to Assess Spatial Learning and Memory
Uploaded: 2024-01-26T12:40:00
Duration: 3 min 39 s
Description: 259 Views. Performing a Virtual Spatial Navigation Task to Assess Spatial Learning and Memory

performing a virtual spatial navigation task to assess spatial learning and memory

Game-Based Exploration: Unlocking Human Spatial Navigation Abilities

Moving the body through time and space is critical for learning and remembering information about the environment. This ability is known as spatial navigation, and evolutionarily speaking, it is an essential survival tool for locating food, water, social counterparts, and other rewards in the environment1,2. Spatial navigation is dependent upon the hippocampus, a c-shaped limbic system structure in the medial temporal lobe. The hippocampus consists of the CA1, CA2, CA3, and dentate gyrus subregions. The hippocampus supports the encoding, consolidation, and retrieval of memories that help define the conscious experience. Specifically, spatial navigation supports episodic memory, a form of explicit memory that refers to the memory of personal experience, including aspects of time, place, and relevant details associated with the experience (e.g., sights, sounds, smells, emotions). As we spatially navigate through distinct environments, neurons known as place cells systematically fire, enabling us to understand where we are in both time and space. In fact, direct optical stimulation of these neurons has been shown to bias the behavior of rodents towards their physical location (i.e., place fields)3.
Assessing spatial navigation in rodents has traditionally been studied through such behavioral paradigms as the Morris Water Maze, Y maze, T maze, and radial arm maze4,5. Importantly, these behavioral tasks allow for the in vivo investigation of the neural correlates of spatial navigation using techniques such as electrophysiological depth recordings. However, assessing spatial navigation in humans has proven scientifically challenging because most scientific investigations happen in laboratories and not out in the real world. Previous studies in humans have assessed spatial abilities with traditional paper-based tasks such as bi-directional map learning tasks, mental rotation tasks, or spatial memory tasks6,7. Others have utilized computer-based tasks such as the Virtual Morris Water Task or other virtual maze tasks, which have been shown to be correlated with more traditional psychometric measures of spatial ability8,9. Additionally, with the accessibility of publicly available and free video game software packages, researchers have begun to develop 3-dimensional virtual environments that can either be presented on a computer screen or in virtual reality10,11,12,13,14,15. Scientific advances in mobile brain-body imaging (MoBI) have also allowed researchers to begin to explore spatial navigation in real-world settings16,17,18.
Importantly, spatial learning and memory is a cognitive ability that deteriorates with age, with elderly individuals being more likely to lose track of where they are or become lost when they try to return home. This deficit is most likely due to neurodegeneration that occurs at the level of the hippocampus - a highly plastic brain area that is one of the first to deteriorate with age19. Therefore, developing real-world methods to assess spatial navigational and episodic memory abilities is an important avenue of research. At the clinical level, these types of tasks may help determine the progression of memory decline or diagnose mild cognitive impairment, Alzheimer&#39;s disease, or other forms of dementia. Conversely, physical activity has been identified as one of the best mechanisms to improve spatial navigational abilities. Studies in rodents have shown that exercise enhances learning and memory on various spatial tasks, including the Morris Water Maze, Y maze, T maze, and radial arm maze20. Exercise-induced improvements in spatial abilities have also been demonstrated in humans, with this effect being significantly related to an increase in hippocampal volume7. However, this behavioral effect was demonstrated using a spatial memory task where participants were asked to remember the locations of dots on a screen - a task that may not hold much ecological validity to real-world spatial navigation. Little research has investigated the impact of exercise in humans on spatial navigational tasks presented in virtual environments.
Therefore, a cognitive task was designed to assess spatial learning and memory along with episodic memory using a virtual environment. Importantly, the task was designed using modern-day video game software to enable up-to-date graphic designs and realistic features (e.g., moving clouds in the sky). This task was tested in a group of healthy adults before and after they experienced long-term aerobic exercise practice. Results indicate that participants can encode and remember both spatial information as well as episodic memories regarding their virtual experience. Additionally, findings indicate that performance on this task is plastic, being affected by exercise.
Specifically, a virtual environment was developed through a cross-platform game engine21 that evaluated spatial navigation and episodic memory ability, unique cognitive skills supported by the hippocampus. The map used for this environment was derived from Miller et al. (2013)22. The game engine that was utilized allows developers to download assets to add unique features for the purposes of building virtual environments. An asset23 was utilized that allowed us to build a realistic city environment with roads and buildings through which participants could navigate. Additionally, an asset24 was used that allowed tracking of participants&#39; x, y, and z coordinates and rotation while they traveled through the virtual environment. The aforementioned asset allowed the recording of these features on a millisecond timescale (~33 ms). The virtual environment was then compiled and administered as a spatial navigation task that participants could complete at home on a laptop or desktop computer. The below protocol details how to administer and engage with this spatial navigation task.

Author Spotlight: Investigating the Effects of Mind-Body-Movement Practices on Brain Function

Assessing Human Spatial Navigation in a Virtual Space and its Sensitivity to Exercise

Performing a Virtual Spatial Navigation Task to Assess Spatial Learning and Memory

performing-virtual-spatial-navigation-task-to-assess-spatial-learning

Research

JoVE Journal

Behavior

259 Views. Performing a Virtual Spatial Navigation Task to Assess Spatial Learning and Memory

Video: Performing a Virtual Spatial Navigation Task to Assess Spatial Learning and Memory

Spatial navigation (SN) is the ability to locomote through the environment, which requires an understanding of where one is located in time and space. This capacity is known to rely on the sequential firing of place cells within the hippocampus. SN is an important behavior to investigate as this process deteriorates with age, especially in neurodegenerative disorders. However, the investigation of SN is limited by the lack of sophisticated behavioral techniques to assess this hippocampal-dependent task. Therefore, the goal of this protocol was to develop a novel, real-world approach to studying SN in humans. Specifically, an active virtual SN task was developed using a cross-platform game engine. During the encoding phase, participants navigated their way through a virtual city to locate landmarks. During the remembering phase, participants remembered where these reward locations were and delivered items to these locations. Time to find each location was captured and episodic memory was assessed by a free recall phase, including aspects of place, order, item, and association. Movement behavior (x, y, and z coordinates) was assessed through an asset available in the game engine. Importantly, results from this task demonstrate that it accurately captures both spatial learning and memory abilities as well as episodic memory. Further, findings indicate that this task is sensitive to exercise, which improves hippocampal functioning. Overall, the findings suggest a novel way to track human hippocampal functioning over the course of time, with this behavior being sensitive to physical activity training paradigms.

Here, we present a novel, brief, and active spatial navigation task that assesses both spatial navigation and episodic memory ability. Importantly, spatial navigation and episodic memory were associated with one another, and this task demonstrated sensitivity to exercise.

Spatial navigation (SN) is the ability to locomote through the environment, which requires an understanding of where one is located in time and space. ...