Landmark

Initially, several specific locations on a virtual table are presented to the subject, where various shapes are displayed in these positions to allow the subject to memorize the association between each shape and its spatial location. Once the stimuli are removed, depending on the task phase, the subject is asked questions such as: “Where was this shape?”, “What was here?”, “What has changed?”, or “What was between these two shapes?”, requiring the subject to retrieve the stored information. As the levels progress, the delay between encoding and recall increases, the number of objects and locations grows, and factors such as sequential presentation, table rotation, visual distractors, and time limits are introduced. These elements progressively increase the demand on visual-spatial memory, working memory, and visual attention.

The therapeutic objective of this exercise is to strengthen visual-spatial memory, enhance object-location learning, and improve the ability to retrieve spatial information. (Functionally dependent on the hippocampus. A distinguishing feature of this task is the dissociation between allocentric memory—independent of the individual’s viewpoint—and egocentric memory—dependent on the individual’s current position. This distinction in spatial memory assessment is specifically linked to hippocampal function.) The subject must be able to memorize object positions within the environment, maintain spatial relationships between them, and accurately retrieve stored information even after changes in conditions or viewpoint. By engaging working memory, visual attention, and change detection, this exercise can be integrated into cognitive rehabilitation programs to preserve or enhance memory functions.

Target Population:

1. Individuals with Mild Cognitive Impairment (MCI).
2. Individuals in the early stages of Alzheimer’s disease.
3. Elderly individuals with age-related complaints or deficits in memory and visual-spatial memory.
4. Individuals experiencing memory or cognitive deficits following a stroke.
5. Individuals with impairments in visual-spatial memory and object-location association learning.
6. Note: This task is specifically designed to differentiate hippocampal-dependent memory deficits from other types of amnesia.

Clinical Applications:

1. The Landmark task is suitable for use in settings such as hospitals, cognitive rehabilitation centers, neurology clinics, occupational therapy centers, geriatric rehabilitation facilities, and post-stroke recovery centers.

Place the VR headset correctly on the subject’s head and prepare the training environment.

Start the exercise from a simpler level; the difficulty will increase progressively based on the subject’s performance.

1. Fine error separation: knew the object but not its place? fooled by a look-alike?
2. The drop caused by island rotation (viewpoint-independent memory)
3. How long a delay between viewing and recall is tolerated