No abstract

Spatial orientation is an important function in daily life because it allows us to reach a target place when moving through our environment, using self-centered (egocentric) or environmental information (allocentric). Compared to other cognitive functions, spatial orientation has been studied less in preschool ages. Some brain areas, such as the hippocampus and the temporal as well as the parietal and frontal cortices, are involved in spatial orientation. Therefore, when these brain regions are altered in neurological conditions or in atypical development in children, we would expect impairment of spatial abilities. The aim of this study is to review studies, published in recent years, that use egocentric and allocentric spatial orientation tasks for assessing spatial memory in preschool children, with the final goal of finding out which tests could be included in a clinical neuropsychological evaluation. We observed that although egocentric spatial orientation emerges first during development, allocentric spatial orientation tasks are employed at very early ages. Most of these tasks are performed in real environments, allowing children's self-movements and using environmental modifications, but technologies such as virtual or augmented reality are increasingly used. Other aspects are discussed, such as the lack of consensus in the nomenclature, the difficulty of tracing the course of development of spatial orientation, or the ecological validity of the tests used. We finally observed that there is greater interest in studying the allocentric framework than the egocentric one, which makes it difficult to compare the use of the two frames of reference during a neuropsychological evaluation in preschool-aged children.

Although normal aging has been related to several cognitive difficulties, other processes have been studied less, such as spatial memory. Our aim was to compare egocentric and allocentric memory in an elderly population using ecological tasks. Twentyeight cognitively unimpaired participants performed Egocentric and Allocentric Spatial Memory Tasks, as well as Spatial Span from CANTAB, Benton's Judge of Line Orientation test (JoLO), and Montreal Cognitive Assessment test (MoCA). The results revealed that younger participants showed better performance than older participants on both the Egocentric and Allocentric Spatial Memory Tasks, although only the Egocentric test was able to discriminate between younger, middle, and older elderly participants. Learning effect was found in Allocentric Spatial Memory Task in younger and older groups, but not in the middle group. Allocentric and egocentric performance was not related to other visuospatial neuropsychological scores and gender did not influence performance in any task. Egocentric and Allocentric Spatial Memory Tasks may be useful tools in early screening for cognitive decline, as they are able to detect age differences in the cognitive unimpaired elderly population.

Background: Visuospatial skills are impaired in Parkinson’s disease (PD). Other related skills exist, such as spatial orientation have been poorly studied. The egocentric (based on internal cues) and allocentric frameworks (based on external cues) are used in daily spatial orientation. Depending on PD onset, the allocentric framework may have a higher level of impairment in tremor-dominant and the egocentric one in akinetic-rigid. Objective: To evaluate spatial orientation and visuospatial functions in PD patients and controls, and to assess whether their performance is related to disease duration and the PD subtype (tremor-dominant and akinetic-rigid). Methods: We evaluated egocentric and allocentric spatial orientation (Egocentric and Allocentric Spatial Memory Tasks) and visuospatial abilities, span and working memory in 59 PD patients and 51 healthy controls. Results: Visuospatial skills, visuospatial span, and egocentric and allocentric orientation are affected in PD. Visuospatial skills and allocentric orientation undergo deterioration during the first 5 years of the disease progression, while egocentric orientation and visuospatial span do so at later stages (9–11 years). The akinetic-rigid subtype presents worse results in all the spatial abilities that were measured when compared to controls, and worse scores in visuospatial working memory, visuospatial abilities and allocentric orientation when compared to the tremor-dominant group. The tremor-dominant group performed worse than controls in egocentric and allocentric orientation. Conclusion: PD patients show deficits in their visuospatial abilities and in their egocentric and allocentric spatial orientation compared to controls, specifically in akinetic-rigid PD. Only spatial orientation are affected in tremor-dominant PD patients. Allocentric orientation is affected earlier in the progression of the disease.

Background: Controversy between short-term neonatal growth of very low birth-weight preterm (VLBW) and neurodevelopment may be affected by criteria changes of extrauterine growth restriction (EUGR). Objective: to determine if new EUGR criteria imply modifications in the relationship between old criteria and results of neuropsychological tests in preterm children. Patients and methods: 87 VLBW at 5–7 years of age were studied. Neuropsychological assessment included RIST test (Reynolds Intellectual Sctreening Test) and NEPSY-II (NE neuro, PSY psycolgy assessment) tests. The relationships between these tests and the different growth parameters were analyzed. Results: RIST index was correlated with z-score Fenton’s weight (p = 0.004) and length (p = 0.003) and with z-score IGW-21’s (INTERGRWTH-21 Project) weight (p = 0.004) and length (p = 0.003) at neonatal discharge, but not with z-score difference between birth and neonatal discharge in weight, length, and HC for both. We did not find a statistically significant correlation between Fenton or IGW-21 z-scores and scalar data of NEPSY-II subtasks. Conclusion: In our series, neonatal growth influence on neuropsychological tests at the beginning of primary school does not seem robust, except for RIST test. New EUGR criteria do not improve the predictive ability of the old ones.