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Spatial Tasks (spatial + task)
Selected AbstractsDissociating hippocampal subregions: A double dissociation between dentate gyrus and CA1HIPPOCAMPUS, Issue 6 2001Paul E. Gilbert Abstract This study presents a double dissociation between the dentate gyrus (DG) and CA1. Rats with either DG or CA1 lesions were tested on tasks requiring either spatial or spatial temporal order pattern separation. To assess spatial pattern separation, rats were trained to displace an object which covered a baited food-well. The rats were then allowed to choose between two identical objects: one covered the same well as the sample phase object (correct choice), and a second object covered a different unbaited well (incorrect choice). Spatial separations of 15,105 cm were used to separate the correct object from the incorrect object. To assess spatial temporal order pattern separation, rats were allowed to visit each arm of a radial eight-arm maze once in a randomly determined sequence. The rats were then presented with two arms and were required to choose the arm which occurred earliest in the sequence. The choice arms varied according to temporal separation (0, 2, 4, or 6) or the number of arms that occurred between the two choice arms in the sample phase sequence. On each task, once a preoperative criterion was reached, each rat was given either a DG, CA1, or control lesion and then retested. The results demonstrated that DG lesions resulted in a deficit on the spatial task but not the temporal task. In contrast, CA1 lesions resulted in a deficit on the temporal task but not the spatial task. Results suggest that the DG supports spatial pattern separation, whereas CA1 supports temporal pattern separation. Hippocampus 2001;11:626,636. © 2001 Wiley-Liss, Inc. [source] Brain Electrical Activity Associated With Cognitive Processing During a Looking Version of the A-Not-B TaskINFANCY, Issue 3 2001Martha Ann Bell This work was designed to investigate individual differences in brain electrical activity during a looking version of the A-not-B task. It was proposed that this spatial task required the cognitive skills of working memory and inhibitory control, each associated with frontal lobe function. Electroencephalograms (EEGs) were recorded from 54 8-month-old infants during baseline and task. Only high performers on the looking task exhibited increases in 6- to 9-Hz EEG power from baseline to task. These task-related changes were evident at frontal and posterior scalp locations. High performers on the looking task exhibited lower EEG coherence values at right hemisphere frontal locations relative to the low performers. These lower coherence values were evident during baseline and task. All infants showed increased frontal-parietal coherence during the spatial working memory task relative to baseline values. These data confirm previous cognitive neuroscience work associating frontal lobe function with cognitive performance levels during infancy. [source] Working memory for ballet moves and spatial locations in professional ballet dancersAPPLIED COGNITIVE PSYCHOLOGY, Issue 2 2010Antonio Cortese The aim of the present study was to investigate working memory for ballet moves in expert dancers. Experiment 1 showed that a concurrent spatial task did not interfere with the recall of a sequence of ballet moves when these were encoded alone without being associated with spatial locations. Experiment 2 showed that a concurrent motor task selectively interfered with the recall of ballet moves while neither a concurrent motor task nor a spatial task affected recall of the specific locations where each ballet move had to be performed. Experiment 3 showed that spatial interference affected recall of sequences of locations when these were encoded alone. Finally, in Experiment 4, a similarity effect for patterned ballet movements was shown. Taken together results show that spatial interference does not affect short-term memory for ballet moves thus suggesting that working memory might contain a system for motor configurations. Copyright © 2009 John Wiley & Sons, Ltd. [source] Complete maternal deprivation affects social, but not spatial, learning in adult ratsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2003F. Lévy Abstract The effects of maternal deprivation on learning of social and spatial tasks were investigated in female adult rats. Pups were reared artificially and received "lickinglike" tactile stimulation (AR animals) or were reared with their mothers (MR animals). In adulthood, subjects were tested on paradigms of spatial learning and on paradigms involving learning of social cues. Results showed that maternal deprivation did not affect performance on spatial learning, but it did impair performance on the three social learning tasks. The AR animals made no distinction between a new and a previously presented juvenile conspecific. AR animals also responded less rapidly than MR animals at test for maternal behavior 2 weeks after a postpartum experience with pups. Finally, AR animals did not develop a preference for a food previously eaten by a familiar conspecific whereas MR animals did. This study indicates that animals reared without mother and siblings show no deficits in spatial tasks while showing consistent deficits in learning involving social interactions. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 43: 177,191, 2003. [source] Developmental profiles for multiple object tracking and spatial memory: typically developing preschoolers and people with Williams syndromeDEVELOPMENTAL SCIENCE, Issue 3 2010Kirsten O'Hearn The ability to track moving objects, a crucial skill for mature performance on everyday spatial tasks, has been hypothesized to require a specialized mechanism that may be available in infancy (i.e. indexes). Consistent with the idea of specialization, our previous work showed that object tracking was more impaired than a matched spatial memory task in individuals with Williams syndrome (WS), a genetic disorder characterized by severe visuo-spatial impairment. We now ask whether this unusual pattern of performance is a reflection of general immaturity or of true abnormality, possibly reflecting the atypical brain development in WS. To examine these two possibilities, we tested typically developing 3- and 4-year-olds and people with WS on multiple object tracking (MOT) and memory for static spatial location. The maximum number of objects that could be correctly tracked or remembered (estimated from the k -statistic) showed similar developmental profiles in typically developing 3- and 4-year-old children, but the WS profile differed from either age group. People with WS could track more objects than 3-year-olds, and the same number as 4-year-olds, but they could remember the locations of more static objects than both 3- and 4-year-olds. Combining these data with those from our previous studies, we found that typically developing children show increases in the number of objects they can track or remember between the ages of 3 and 6, and these increases grow in parallel across the two tasks. In contrast, object tracking in older children and adults with WS remains at the level of 4-year-olds, whereas the ability to remember multiple locations of static objects develops further. As a whole, the evidence suggests that MOT and memory for static location develop in tandem typically, but not in WS. Atypical development of the parietal lobe in people with WS could play a causal role in the abnormal, uneven pattern of performance in WS. This interpretation is consistent with the idea that multiple object tracking engages different mechanisms from those involved in memory for static object location, and that the former can be particularly disrupted by atypical development. [source] Genetic ablation of the mammillary bodies in the Foxb1 mutant mouse leads to selective deficit of spatial working memoryEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2005Konstantin Radyushkin Abstract Mammillary bodies and the mammillothalamic tract are parts of a classic neural circuitry that has been implicated in severe memory disturbances accompanying Korsakoff's syndrome. However, the specific role of mammillary bodies in memory functions remains controversial, often being considered as just an extension of the hippocampal memory system. To study this issue we used mutant mice with a targeted mutation in the transcription factor gene Foxb1. These mice suffer perinatal degeneration of the medial and most of the lateral mammillary nuclei, as well as of the mammillothalamic bundle. Foxb1 mutant mice showed no deficits in such hippocampal-dependent tasks as contextual fear conditioning and social transmission of food preference. They were also not impaired in the spatial reference memory test in the radial arm maze. However, Foxb1 mutants showed deficits in the task for spatial navigation within the Barnes maze. Furthermore, they showed impairments in spatial working memory tasks such as the spontaneous alternation and the working memory test in the radial arm maze. Thus, our behavioural analysis of Foxb1 mutants suggests that the medial mammillary nuclei and mammillothalamic tract play a role in a specific subset of spatial tasks, which require combined use of both spatial and working memory functions. Therefore, the mammillary bodies and the mammillothalamic tract may form an important route through which the working memory circuitry receives spatial information from the hippocampus. [source] Excitotoxic lesions of the pre- and parasubiculum disrupt the place fields of hippocampal pyramidal cellsHIPPOCAMPUS, Issue 1 2004Ping Liu Abstract To determine what influence the pre- and parasubiculum regions of the hippocampal formation have on neural representations within the dorsal hippocampus, single-unit recordings were made as rats with bilateral ibotenic acid lesions centered on the former regions (n = 4) or control surgeries (n = 3) foraged freely. Spatial firing specificity was measured using an information content procedure. Cells from lesioned animals (n = 57) provided significantly less spatial information than cells from control animals (n = 44). Whereas some degree of location-related activity (place fields) was observed in 98% of neurons recorded from control animals, it was observed in only 65% of the neurons from lesioned animals. The spatial resolution of the intact place fields appeared to be compromised in lesioned animals as a result of their having a higher firing rate outside the place field. These findings indicate that the pre- and parasubiculum regions have a major role in maintaining the specificity of the place field firing of hippocampal pyramidal cells. Since previous data indicate that these lesioned animals displayed delay-dependent deficits in spatial tasks, these findings also suggest that a disruption in place field activity may be a causal factor in this spatial memory deficit. © 2003 Wiley-Liss, Inc. [source] Neuropsychological components of intellectual disability: the contributions of immediate, working, and associative memoryJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 5 2010Jamie O. Edgin Abstract Background Efficient memory functions are important to the development of cognitive and functional skills, allowing individuals to manipulate and store information. Theories of memory have suggested the presence of domain-specific (i.e. verbal and spatial) and general processing mechanisms across memory domains, including memory functions dependent on the prefrontal cortex (PFC) and the hippocampus. Comparison of individuals who have syndromes associated with striking contrasts in skills on verbal and spatial tasks [e.g. Down syndrome (DS) and Williams syndrome (WS)] allows us to test whether or not these dissociations may extend across cognitive domains, including PFC and hippocampal memory processes. Methods The profile of memory function, including immediate memory (IM), working memory (WM) and associative memory (AM), was examined in a sample of adolescents and young adults with DS (n = 27) or WS (n = 28), from which closely CA- and IQ-matched samples of individuals with DS (n = 18) or WS (n = 18) were generated. Relations between memory functions and IQ and adaptive behaviour were also assessed in the larger sample. Results Comparisons of the two matched groups indicated significant differences in verbal IM (DS < WS), spatial IM (DS > WS) and spatial and verbal AM (DS > WS), but no between-syndrome differences in WM. For individuals with DS, verbal IM was the most related to variation in IQ, and spatial AM related to adaptive behaviour. The pattern was clearly different for individuals with WS. Verbal and spatial AM were the most related to variation in IQ, and verbal WM related to adaptive behaviour. Conclusions These results suggest that individuals with these two syndromes have very different patterns of relative strengths and weaknesses on memory measures, which do not fully mirror verbal and spatial dissociations. Furthermore, different patterns of memory dysfunction relate to outcome in individuals with each syndrome. [source] The evolution of intelligence: adaptive specializations versus general processBIOLOGICAL REVIEWS, Issue 3 2001EUAN M. MAGPHAIL ABSTRACT Darwin argued that between-species differences in intelligence were differences of degree, not of kind. The contemporary ecological approach to animal cognition argues that animals have evolved species-specific and problem-specific processes to solve problems associated with their particular ecological niches: thus different species use different processes, and within a species, different processes are used to tackle problems involving different inputs. This approach contrasts both with Darwin's view and with the general process view, according to which the same central processes of learning and memory are used across an extensive range of problems involving very different inputs. We review evidence relevant to the claim that the learning and memory performance of non-human animals varies according to the nature of the stimuli involved. We first discuss the resource distribution hypothesis, olfactory learning-set formation, and the ,biological constraints' literature, but find no convincing support from these topics for the ecological account of cognition. We then discuss the claim that the performance of birds in spatial tasks of learning and memory is superior in species that depend heavily upon stored food compared to species that either show less dependence upon stored food or do not store food. If it could be shown that storing species enjoy a superiority specifically in spatial (and not non-spatial) tasks, this would argue that spatial tasks are indeed solved using different processes from those used in non-spatial tasks. Our review of this literature does not find a consistent superiority of storing over non-storing birds in spatial tasks, and, in particular, no evidence of enhanced superiority of storing species when the task demands are increased, by, for example, increasing the number of items to be recalled or the duration of the retention period. We discuss also the observation that the hippocampus of storing birds is larger than that of non-storing birds, and find evidence contrary to the view that hippocampal enlargement is associated with enhanced spatial memory; we are, however, unable to suggest a convincing alternative explanation for hippocampal enlargement. The failure to find solid support for the ecological view supports the view that there are no qualitative differences in cognition between animal species in the processes of learning and memory. We also argue that our review supports our contention that speculation about the phylogenetic development and function of behavioural processes does not provide a solid basis for gaining insight into the nature of those processes. We end by confessing to a belief in one major qualitative difference in cognition in animals: we believe that humans alone are capable of acquiring language, and that it is this capacity that divides our intelligence so sharply from non-human intelligence. [source] Strategy Generalization Across Orientation Tasks: Testing a Computational Cognitive ModelCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 5 2008Glenn Gunzelmann Abstract Humans use their spatial information processing abilities flexibly to facilitate problem solving and decision making in a variety of tasks. This article explores the question of whether a general strategy can be adapted for performing two different spatial orientation tasks by testing the predictions of a computational cognitive model. Human performance was measured on an orientation task requiring participants to identify the location of a target either on a map (find-on-map) or within an egocentric view of a space (find-in-scene). A general strategy instantiated in a computational cognitive model of the find-on-map task, based on the results from Gunzelmann and Anderson (2006), was adapted to perform both tasks and used to generate performance predictions for a new study. The qualitative fit of the model to the human data supports the view that participants were able to tailor a general strategy to the requirements of particular spatial tasks. The quantitative differences between the predictions of the model and the performance of human participants in the new experiment expose individual differences in sample populations. The model provides a means of accounting for those differences and a framework for understanding how human spatial abilities are applied to naturalistic spatial tasks that involve reasoning with maps. [source] | ||||||||||||||||