In cognitive psychology and neuroscience, spatial memory is a form of memory responsible for the recording and recovery of information needed to plan a course to a location and to recall the location of an object or the occurrence of an event. Spatial memory is necessary for orientation in space.
Spatial memory has representations within working, short-term memory and long-term memory. Research indicates that there are specific areas of the brain associated with spatial memory. Many methods are used for measuring spatial memory in children, adults, and animals.
One influential theory of WM is the Alan Baddeley and Hitch multi-component model of working memory. The most recent version of this model suggests that there are four subcomponents to WM: phonological loop, the visuo-spatial sketchpad, the central executive, and the episodic buffer. One component of this model, the visuo-spatial sketchpad, is likely responsible for the temporary storage, maintenance, and manipulation of both visual and spatial information.
In contrast to the multi-component model, some researchers believe that STM should be viewed as a unitary construct. In this respect, visual, spatial, and verbal information are thought to be organized by levels of representation rather than the type of store to which they belong. Within the literature, it is suggested that further research into the fractionation of STM and WM be explored. However, much of the research into the visuo-spatial memory construct have been conducted in accordance to the paradigm advanced by Baddeley and Hitch.
Additionally, during a spatial visualisation task (which is related to executive functioning and not STM or WM) concurrent executive suppression impaired performance indicating that the effects were due to common demands on the central executive and not short-term storage. The researchers concluded with the explanation that the central executive employs Cognitive style enabling participants to both encode and maintain mental representations during short-term memory tasks.
Although studies suggest that the central executive is intimately involved in a number of spatial tasks, the exact way in which they are connected remains to be seen.
A cognitive map is "a mental model of objects' spatial configuration that permits navigation along optimal path between arbitrary pairs of points." This mental map is built upon two fundamental bedrocks: layout, also known as route knowledge, and landmark orientation. Layout is potentially the first method of navigation that people learn to utilize; its workings reflect our most basic understandings of the world.
Hermer and Spelke (1994) determined that when toddlers begin to walk, around eighteen months, they navigate by their sense of the world's layout. McNamara, Hardy and Hirtle identified region membership as a major building block of anyone's cognitive map (1989). Specifically, region membership is defined by any kind of boundary, whether physical, perceptual or subjective (McNamara et al., 1989). Boundaries are among the most basic and endemic qualities in the world around us. These boundaries are nothing more than axial lines which are a feature that people are biased towards when relating to space; for example, one axial line determinant is gravity (McNamara & Shelton, 2001; Kim & Penn, 2004). Axial lines aid everyone in apportioning our perceptions into regions. This parceled world idea is further supported by the finding that items that get recalled together are more likely than not to also be clustered within the same region of one's larger cognitive map. Clustering shows that people tend to chunk information together according to smaller layouts within a larger cognitive map.
Boundaries are not the only determinants of layout. Clustering also demonstrates another important property of relation to spatial conceptions, which is that spatial recall is a hierarchical process. When someone recalls an environment or navigates terrain, that person implicitly recalls the overall layout at first. Then, due to the concept's "rich correlational structure", a series of associations become activated. Eventually, the resulting cascade of activations will awaken the particular details that correspond with the region being recalled. This is how people encode many entities from varying ontological levels, such as the location of a stapler; in a desk; which is in the office.
One can recall from only one region at a time (a bottleneck). A bottleneck in a person's cognitive navigational system could be an issue. For instance, if there were a need for a sudden detour on a long road trip. Lack of experience in a locale, or simply sheer size, can disorient one's mental layout, especially in a large and unfamiliar place with many overwhelming stimuli. In these environments, people are still able to orient themselves, and find their way around using landmarks. This ability to "prioritize objects and regions in complex scenes for selection (and) recognition" was labeled by Chun and Jiang in 1998. Landmarks give people guidance by activating "learned associations between the global context and target locations." Mallot and Gillner (2000) showed that subjects learned an association between a specific landmark and the direction of a turn, thereby furthering the relationship between associations and landmarks. Shelton and McNamara (2001) succinctly summed up why landmarks, as markers, are so helpful: "location...cannot be described without making reference to the orientation of the observer."
People use both the layout of a particular space and the presence of orienting landmarks in order to navigate. Psychologists have yet to explain whether layout affects landmarks or if landmarks determine the boundaries of a layout. Because of this, the concept suffers from a chicken and the egg paradox. McNamara has found that subjects use "clusters of landmarks as intrinsic frames of reference," which only confuses the issue further.
People perceive objects in their environment relative to other objects in that same environment. Landmarks and layout are complementary systems for spatial recall, but it is unknown how these two systems interact when both types of information are available. As a result, people have to make certain assumptions about the interaction between the two systems. For example, cognitive maps are not "absolute" but rather, as anyone can attest, are "used to provide a default...(which) modulated according to...task demands." Psychologists also think that cognitive maps are instance based, which accounts for "discriminative matching to past experience."
This field has traditionally been hampered by confounding variables, such as cost and the potential for previous exposure to an experimental environment. Technological advancements, including those in virtual reality technology, have made findings more accessible. Virtual reality affords experimenters the luxury of extreme control over their test environment. Any variable can be manipulated, including things that would not be possible in reality.
A study conducted at the University of Maryland compared the effect of different levels of immersion on spatial memory recall. In the study, 40 participants used both a traditional desktop and a head-mounted display to view two environments, a medieval town, and an ornate palace, where they memorized two sets of 21 faces presented as 3D portraits. After viewing these 21 faces for 5 minutes, followed by a brief rest period, the faces in the virtual environments were replaced with numbers, and participants recalled which face was at each location. The study found on average, those who used the head-mounted display recalled the faces 8.8% more accurately, and with a greater confidence. The participants state that leveraging their innate vestibular and proprioceptive senses with the head-mounted display and mapping aspects of the environment relative to their body, elements that are absent with the desktop, was key to their success.
An interesting study investigating Taxicab drivers' memory for streets in Helsinki, Finland, examined the role of prelearned spatial knowledge. This study compared experts to a control group to determine how this prelearned knowledge in their skill domain allows them to overcome the capacity limitations of STM and WM. The study used four levels of spatial randomness:
The results of this study indicate that the taxi drivers' (experts') recall of streets was higher in both the route order condition and the map order condition than in the two random conditions. This indicates that the experts were able to use their prelearned spatial knowledge to organize the information in such a way that they surpassed STM and WM capacity limitations. The organization strategy that the drivers employed is known as chunking. Additionally, the comments made by the experts during the procedure point towards their use of route knowledge in completing the task. To ensure that it was in fact spatial information that they were encoding, the researchers also presented lists in alphabetical order and Semantics categories. However, the researchers found that it was in fact spatial information that the experts were chunking, allowing them to surpass the limitations of both visuo-spatial STM and WM.
The evidence for the spatial memory of some species of animals, such as rats, indicates that they do use spatial memory to locate and retrieve hidden food stores.
A study using GPS tracking to see where domestic cats go when their owners let them outside reported that cats have substantial spatial memory. Some of the cats in the study demonstrated exceptional long term spatial memory. One of them, usually traveling no further than to from its home, unexpectedly traveled some from its home. Researchers initially thought this to be a GPS malfunction, but soon discovered that the cat's owners went out of town that weekend, and that the house the cat went to was the owner's old house. The owners and the cat had not lived in that house for well over a year.
Visual memory is responsible for retaining visual shapes and colors (i.e., what), whereas spatial memory is responsible for information about locations and movement (i.e., where). This distinction is not always straightforward since part of visual memory involves spatial information and vice versa. For example, memory for object shapes usually involves maintaining information about the spatial arrangement of the features which define the object in question.
In practice, the two systems work together in some capacity but different tasks have been developed to highlight the unique abilities involved in either visual or spatial memory. For example, the visual patterns test (VPT) measures visual span whereas the Corsi Blocks Task measures spatial span. Correlational studies of the two measures suggest a separation between visual and spatial abilities, due to a lack of correlation found between them in both healthy and brain damaged patients.
Support for the division of visual and spatial memory components is found through experiments using the dual-task paradigm. A number of studies have shown that the retention of visual shapes or colors (i.e., visual information) is disrupted by the presentation of irrelevant pictures or dynamic visual noise. Conversely, the retention of location (i.e., spatial information) is disrupted only by spatial tracking tasks, spatial tapping tasks, and eye movements. For example, participants completed both the VPT and the Corsi Blocks Task in a selective interference experiment. During the retention interval of the VPT, the subject viewed irrelevant pictures (e.g., avant-garde paintings). The spatial interference task required participants to follow, by touching the stimuli, an arrangement of small wooden pegs which were concealed behind a screen. Both the visual and spatial spans were shortened by their respective interference tasks, confirming that the Corsi Blocks Task relates primarily to spatial working memory.
The test was created by Canadians Neuropsychology Phillip Corsi, who modeled it after Hebb's Memory span task by replacing the numerical test items with spatial ones. On average, most participants achieve a span of five items on the Corsi span test and seven on the digit span task.
In most cases, the rat is placed in the center of the maze and needs to explore each arm individually to retrieve food while simultaneously remembering which arms it has already pursued. The maze is set up so the rat is forced to return to the center of the maze before pursuing another arm. Measures are usually taken to prevent the rat from using its Olfaction senses to Navigation such as placing extra food throughout the bottom of the maze.
Typically, rats swim around the edge of the pool first before venturing out into the center in a meandering pattern before stumbling upon the hidden platform. However, as time spent in the pool increases experience, the amount of time needed to locate the platform decreases, with veteran rats swimming directly to the platform almost immediately after being placed in the water. Due to the nature of task involving rats to swim, most researchers believe that habituation is required to decrease the stress levels of the animal. The stress of the animal may impair cognitive testing results.
Blocking Neuroplasticity in this region results in problems in goal-directed navigation and impairs the ability to remember precise locations. Amnesic patients with damage to the hippocampus cannot learn or remember spatial layouts, and patients having undergone hippocampal removal are severely impaired in spatial navigation.
Monkeys with lesions to this area cannot learn object-place associations and rats also display spatial deficits by not reacting to spatial change. In addition, rats with hippocampal lesions were shown to have temporally ungraded (time-independent) retrograde amnesia that is resistant to recognition of a learned platform task only when the entire hippocampus is lesioned, but not when it is partially lesioned. Deficits in spatial memory are also found in spatial discrimination tasks.
Large differences in spatial impairment are found among the dorsal and ventral hippocampus. Lesions to the ventral hippocampus have no effect on spatial memory, while the dorsal hippocampus is required for retrieval, processing short-term memory and transferring memory from the short term to longer delay periods. Infusion of amphetamine into the dorsal hippocampus has also been shown to enhance memory for spatial locations learned previously. These findings indicate that there is a functional dissociation between the dorsal and ventral hippocampus.
Hemispheric differences within the hippocampus are also observed. A study on London taxi drivers, asked drivers to recall complex routes around the city as well as famous for which the drivers had no knowledge of their spatial location. This resulted in an activation of the right hippocampus solely during recall of the complex routes which indicates that the right hippocampus is used for navigation in large scale spatial environments.
The hippocampus is known to contain two separate memory circuits. One circuit is used for recollection-based place recognition memory and includes the entorhinal-CA1 system, while the other system, consisting of the hippocampus trisynaptic loop (entohinal-dentate-CA3-CA1) is used for place recall memory and facilitation of plasticity at the entorhinal-dentate synapse in mice is sufficient to enhance place recall.
are also found in the hippocampus.
Rats with lesions to the anterior region of the posterior parietal cortex reexplore displaced objects, while rats with lesions to the posterior region of the posterior parietal cortex displayed no reaction to spatial change.
Parietal cortex lesions are also known to produce temporally ungraded retrograde amnesia.
The entorhinal cortex contributes to the processing and integration of geometric properties and information in the environment. Lesions to this region impair the use of distal but not proximal landmarks during navigation and produces a delay-dependent deficit in spatial memory that is proportional to the length of the delay. Lesions to this region are also known to create retention deficits for tasks learned up to 4 weeks but not 6 weeks prior to the lesions.
Memory consolidation in the entorhinal cortex is achieved through extracellular signal-regulated kinase activity.
Hemisphere specialization is found in this brain region. The left prefrontal cortex preferentially processes categorical spatial memory including source memory (reference to spatial relationships between a place or event), while the right prefrontal cortex preferentially processes coordinate spatial memory including item memory (reference to spatial relationships between features of an item).
Lesions to the medial prefrontal cortex impair the performance of rats on a previously trained radial arm maze, but rats can gradually improve to the level of the controls as a function of experience. Lesions to this area also cause deficits on delayed nonmatching-to-positions tasks and impairments in the acquisition of spatial memory tasks during training trials.
Lesions to the retrosplenial cortex consistently impair tests of allocentric memory, while sparing egocentric memory. Animals with lesions to the caudal retrosplenial cortex show impaired performance on a radial arm maze only when the maze is rotated to remove their reliance on intramaze cues.
In humans, damage to the retrosplenial cortex results in topographical disorientation. Most cases involve damage to the right retrosplenial cortex and include Brodmann area 30. Patients are often impaired at learning new routes and at navigating through familiar environments. However, most patients usually recover within 8 weeks.
The retrosplenial cortex preferentially processes spatial information in the right hemisphere.
Lesions in the perirhinal cortex account for deficits in reference memory and working memory, and increase the rate of forgetting of information during training trials of the Morris water maze. This accounts for the impairment in the initial acquisition of the task. Lesions also cause impairment on an object location task and reduce habituation to a novel environment.
Spatial learning requires both NMDA receptor and AMPA receptor receptors, consolidation requires NMDA receptors, and the retrieval of spatial memories requires AMPA receptors. In rodents, spatial memory has been shown to covary with the size of a part of the hippocampal mossy fiber projection.
The function of NMDA receptors varies according to the subregion of the hippocampus. NMDA receptors are required in the CA3 of the hippocampus when spatial information needs to be reorganized, while NMDA receptors in the CA1 are required in the acquisition and retrieval of memory after a delay, as well as in the formation of CA1 place fields. Blockade of the NMDA receptors prevents induction of long-term potentiation and impairs spatial learning.
The CA3 of the hippocampus plays an especially important role in the encoding and retrieval of spatial memories. The CA3 is innervated by two afferent paths known as the perforant path (PPCA3) and the dentate gyrus (DG)-mediated mossy fibers (MFs). The first path is regarded as the retrieval index path while the second is concerned with encoding.
Developmental topographical disorientation (DTD) is diagnosed when patients have shown an inability to Navigation even familiar surroundings since birth and show no apparent neurological causes for this deficiency such as lesioning or brain damage. DTD is a relatively new disorder and can occur in varying degrees of severity.
A study was done to see if topographical disorientation had an effect on individuals who had mild cognitive impairment (MCI). The study was done by recruiting forty-one patients diagnosed with MCI and 24 healthy control individuals. The standards that were set for this experiment were:
Rats are commonly used as models of schizophrenia patients. Experimenters create lesions in the ventral hippocampal area shortly after birth, a procedure known as neonatal ventral hippocampal lesioning (NVHL). Adult rats with NVHL show typical indicators of schizophrenia, such as hypersensitivity to Stimulant, reduced social interactions and impaired prepulse inhibition, working memory and set-shifting. Similar to schizophrenia, impaired rats fail to use environmental context in spatial learning tasks such as showing difficulty completing the radial arm maze and the Moris water maze.Winocur, G. & Mills, J. A. (1970). Transfer between related and unrelated problems following hippocampal lesions in rats. Journal of Comparative and Physiological Psychology
However, this loss in confidence in one's own skills is counteracted by the knowledge that getting lost is no longer a problem, thanks to the GPS on our phones, which in turn restores our confidence in our wayfinding ability. Some beneficial outcomes attributed to GPS assistance are more efficient and accurate navigation, coupled with a significant reduction in the cognitive load required for navigation. When people use GPS devices, they do not have to worry about remembering the route, paying attention to landmarks, or constantly checking maps. This can free up cognitive resources for other tasks, leading to better performance on such tasks and higher levels of concentration and focus. This allows to free up cognitive resources to facilitate information processing and learning.
To compensate for the issues that arise from GPS use, there has been substantial research that proposes alternative forms of GPS navigation or additions to the existing ones that have been shown to enhance spatial learning. A study from 2021 implemented a 3D spatial audio system similar to an auditory compass, where users are directed towards their destination without explicit directions. Rather than being led passively through verbal directions, users are encouraged to take an active role in their own spatial navigation. This led to more accurate cognitive maps of space, an improvement which was demonstrated when the participants of the study drew precise maps after performing a scavenger hunt task. Another study suggested highlighting local features like landmarks, along the route and at decision points; or highlighting structural features that provide global orientation (not the details concerning the route taken by the study's participants, but landmarks of the larger area surrounding it). The study showed that accentuating local features in wayfinding maps (GPS) supports the acquisition of route knowledge, which was measured with a pointing and a global feature recall task.
Also, in Blindness and visually impaired people the use of GPS provide advantages in spatial learning and memory. Blind and visually impaired people often need to obtain information about locations ahead of time and practice along a specific route with the help of a relative, friend or specialized instructor before traveling the route to said destination independently. GPS comes in by offering helpful information therefore allowing them to become more independent and confident with their travel to a specific destination.
Another research paper claims that a GPS can be used for patients suffering from dementia.
In a study done in 2014, drivers with mild to very mild Alzheimer's disease (AD) were administered 3 driving trials with different GPS settings (normal, visual-only and audio-only). The participants were required to perform a variety of driving tasks on a driving simulator following the GPS instructions. This study has found that using single, simple auditory instructions with the absence of the visual output of the GPS could potentially help people with mild AD to improve their driving ability and reach their destination, therefore confirming that GPS use does reduce cognitive loads.
Since GPS use would help the patients with wayfinding, it would allow them to stay safe in public, reclaim their sense of self-sufficiency, and discourage "wandering". Overall, evidence is strongest about the use of GPS technologies for averting harm and promoting wellbeing.
The impact of GPS use on spatial learning and memory is not yet fully understood, and further research is needed to explore the long-term effects of GPS use on these cognitive processes. However, it is clear that GPS technology has both benefits and drawbacks, and users should be aware of the potential impact of their reliance on GPS.
In conclusion, GPS technology has revolutionized the way we navigate and explore our environment, but its impact on our spatial learning and memory is still a subject of debate. While GPS use can help people navigate more efficiently, confidently, and aid populations who would otherwise be significantly hindered; its use may lead to a decline in spatial cognitive skills over time. Therefore, it is essential for users to balance the benefits and drawbacks of GPS use and to be aware of its potential impact on their cognitive abilities.
Arithmetic word problems involve written text containing a set of data followed by one or more questions and require the use of the four basic arithmetic operations (addition, subtraction, multiplication, or division). Researchers suggest that successful completion of arithmetic word problems involves spatial working memory (involved in building schematic representations) which facilitates the creation of spatial relationships between objects. Creating spatial relationships between objects is an important part of solving word problems because mental operations and transformations are required.
Researchers investigated the role of spatial memory and visual memory in the ability to complete arithmetic word problems. Children in the study completed the Corsi block task (forward and backward series) and a spatial matrix task, as well as a visual memory task called the house recognition test. Poor Problem solving were impaired on the Corsi block tasks and the spatial matrix task, but performed normally on the house recognition test when compared to normally achieving children. The experiment demonstrated that poor problem solving is related specifically to deficient processing of spatial information.
Further, it has been illustrated that early and late nocturnal sleep have different effects on spatial memory. N3 of the NREM sleep, also referred to as Slow-wave sleep (SWS), is supposed to have a salient role for the sleep-dependent creation of spatial memory in humans. Particularly in the study conducted by Plihal and Born (1999), the performance on mental rotation tasks was higher among participants who had early sleep intervals (23.00–02.00 am) after learning the task compared to the ones who had late sleep intervals (03.00–06.00 am). These results suggest that early sleep, which is rich in SWS, has certain benefits for the formation of spatial memory. When researchers examined whether early sleep would have such an impact on word stem priming task (verbal task), the results were the opposite. This was not surprising for researchers as priming tasks mostly rely on procedural memory, and thus, it benefits more late retention sleep (dominated by REM sleep) rather than early.
Sleep deprivation and sleep has also been a researched association. Sleep deprivation hinders memory performance improvement due to an active disruption of spatial memory consolidation. As a result, spatial memory is enhanced by a period of sleep. Similar results were confirmed by another study examining the impact of total sleep deprivation (TSD) on rats' spatial memory (Guan et al., 2004). In the first experiment conducted, the rats were trained in Morris water maze for 12 trials in 6 hours to find a hidden platform (transparent and not visible in the water) by using spatial cues in the environment. In each trial, they started from a different point and were allowed to swim for a maximum of 120 s to reach the platform. After the learning phase, they gave a probe trial to test spatial memory (after 24 h). In this trial, the hidden platform was removed from the maze and the time animals spent in the target area (which was occupied by hidden platform before) was a measure of spatial memory persistence. The control rats, who had spontaneous sleep, spent significantly more time in the target quadrant compared to ones who had total sleep deprivation. In terms of spatial learning, which is indicated by the latency to find the hidden platform, there were no differences. For both control and sleep deprived rats, the time required to find a platform was decreasing with every new trial.
In the second experiment, the rats were trained to swim to a visible platform whose location was changed in each trial. For every new trial, the rats started from the opposite side of the platform. After the training in a single trial, their memory was tested after 24 h. Platform was still in the maze. The distance and the time they needed to swim to the visible platform were considered as non-spatial memory measures. No significant difference has been found between sleep deprived rats and control rats. Similarly, in terms of spatial learning, which is indicated by latency to reach the visible platform, there were no significant differences. TSD does not affect non-spatial learning and non-spatial memory.
In reference to the effects of sleep deprivation on humans, Dominique Piber (2021) featured in his literature review the clinical observations which shows that people with severe frequently have abnormalities in spatial memory. As visible in the studies of both, insomnia patients who suffer from a sleep disorder which features interrupted, non-restorative sleep and deficits in cognitive performance during the day, are documented to have a negative performance in a spatial task, in comparison with the healthy participants (Li et al., 2016; Chen et al., 2016; Khassawneh et al., 2018; He et al., 2021).
Likewise, dreaming has an important role in spatial memory. A study conducted by Wamsley and Stickgold (2019) proved that participants, who incorporate a recent learning experience into their overnight dream content, show an increased overnight performance improvement. Thus, supporting the hypothesis that dreaming reflects memory processing in the sleeping brain. Moreover, according to the authors, one of the explanations is that maze‐related dreams are indicators that performance‐relevant components of task memory are being reactivated in the sleeping brain. Additionally, the study supports the idea that dream reports can include an experimental learning task during all stages of sleep, including REM and NREM.
Virtual reality (VR) has also been used to study the connection between dreams and spatial memory. Ribeiro, Gounden, and Quaglino (2021) proposed spatialized elements in a VR context and found that after a full night of sleep in a home setting, when the material studied was incorporated into the dream content, the recall performance of these elements was better than the performance obtained after a comparable wake period.
Posterior parietal cortex
Entorhinal cortex
Prefrontal cortex
Retrosplenial cortex
Perirhinal cortex
Neuroplasticity
Disorders/deficits
Topographical disorientation
TD was assessed clinically in all participants. Neurological and neuropsychological evaluations were determined by a magnetic imaging scan which was performed on each participant. Voxel-based morphometry was used to compare patterns of gray-matter atrophy between patients with and without TD, and a group of normal controls. The outcome of the experiment was that they found TD in 17 out of the 41 MCI patients (41.4%). The functional abilities were significantly impaired in MCI patients with TD compared to in MCI patients without TD and that the presence of TD in MCI patients is associated with loss of gray matter in the medial temporal regions, including the hippocampus.
Hippocampal damage and schizophrenia
NEIL1
GPS use and Spatial Cognition
Learning difficulties
Sleep
See also
External links
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