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PubMed2024

Integration of Imaging-based and Sequencing-based Spatial Omics Mapping on the Same Tissue Section via DBiTplus.

Spatially mapping the transcriptome and proteome in the same tissue section can significantly advance our understanding of heterogeneous cellular processes and connect cell type to function. Here, we present Deterministic Barcoding in Tissue sequencing plus (DBiTplus), an integrative multi-modality spatial omics approach that combines sequencing-based spatial transcriptomics and image-based spatial protein profiling on the same tissue section to enable both single-cell resolution cell typing and genome-scale interrogation of biological pathways. DBiTplus begins with in situ reverse transcription for cDNA synthesis, microfluidic delivery of DNA oligos for spatial barcoding, retrieval of barcoded cDNA using RNaseH, an enzyme that selectively degrades RNA in an RNA-DNA hybrid, preserving the intact tissue section for high-plex protein imaging with CODEX. We developed computational pipelines to register data from two distinct modalities. Performing both DBiT-seq and CODEX on the same tissue slide enables accurate cell typing in each spatial transcriptome spot and subsequently image-guided decomposition to generate single-cell resolved spatial transcriptome atlases. DBiTplus was applied to mouse embryos with limited protein markers but still demonstrated excellent integration for single-cell transcriptome decomposition, to normal human lymph nodes with high-plex protein profiling to yield a single-cell spatial transcriptome map, and to human lymphoma FFPE tissue to explore the mechanisms of lymphomagenesis and progression. DBiTplusCODEX is a unified workflow including integrative experimental procedure and computational innovation for spatially resolved single-cell atlasing and exploration of biological pathways cell-by-cell at genome-scale.

Journal Article↗
PubMed1994

Interference in immediate spatial memory.

It has been suggested that maintenance in visuospatial immediate memory involves implicit motor processes that are analogous to the articulatory loop in verbal memory. An alternative account, which is explored here, is that maintenance is based on shifts of spatial attention. In four experiments, subjects recalled spatial memory span items after an interval, and in a fifth experiment, digit span was recalled after an interval. The tasks carried out during the interval included touching visual targets, repeating heard words, listening to tones from spatially separated locations, pointing to these tones, pointing to visual targets, and categorizing spatial targets as being from the left or right. Spatial span recall was impaired if subjects saw visual targets or heard tones, and this impairment was increased if either a motor response or a categorical response was made. Repeating words heard in different spatial locations did not impair recall, but reading visually presented words did interfere. For digit span only, the tasks involving a verbal response impaired recall. The results are interpreted within a framework in which active spatial attention is involved in maintaining spatial items in order in memory, and is interfered with by any task (visual, auditory, perceptual, motor) that also makes demands on spatial attention.

Acoustic Stimulation↗
PubMed2000

[Spatial frequency tuning characteristics of cat primary visual cortex at different topological locations by optical imaging].

Using optical imaging based on intrinsic signals, we studied spatial frequency tuning characteristics of cat primary visual cortex at different visual topological locations. We found that the areas representing the peripheral visual field had null or very weak responses to high spatial frequency grating stimuli, whereas the areas representing the central visual field responded to the stimuli of a wide range of spatial frequencies with greater responses to high spatial frequencies. The more centered the corresponding visual field of the cortical area, the higher the cutoff spatial frequency. The spatial frequency tuning curves also tended to have a smooth shift along the cortical surface. The results above demonstrate that spatial frequency tuning characteristics of the primary visual cortex change according to different visual topological locations of the cortical areas, in addition to the existence of spatial frequency columns. It is suggested that the distribution of spatial frequency columns may be related to visual topology.

Animals↗
PubMed2002

[Spatial heterogeneity and forest regeneration].

The research on spatial heterogeneity is meaningful for forest regeneration dynamics, which is a critical part in the forest ecosystem dynamics. Traditionally, forestry scientists are mainly concentrated their attention to the studies on the process of regeneration. However forests are spatiotemporal heterogeneous. In regeneration, there exists an ecological dynamic process at temporal scale, but also a heterogeneous pattern at spatial scale. Almost of the factors influencing forest regeneration, including both botic and abotic environment, both natural and human disturbances, and both characteristics of tree species and response of tree species to different disturbance agents, are spatially heterogeneous. Discussion on spatial heterogeneity and its effect on regeneration is indispensable for the understanding of the pattern, process and mechanism of forest regeneration. Main research contents and viewpoints of spatial heterogeneity in forest regeneration were summarised on the basis of available literature, and sources of spatial heterogeneity in the process of regeneration were analysed. The response of species to spatial heterogeneity, small-scale spatial heterogeneity and regeneration dynamics, spatial heterogeneity of lights in stand and regeneration pattern, and correlative relationships between the scales of soil heterogeneity and regeneration heterogeneity were reviewed.

Trees↗
PubMed2003

GABA is involved in spatial unmasking in the frog auditory midbrain.

Real-world listening situations comprise multiple auditory objects. Sounds originating from different objects are summated at the eardrum. The auditory system therefore must segregate the streams of sounds associated with the different objects. One listening strategy in complex environments is to attend to signals originating from one spatial location. In doing so, signal detection is compromised when a masker is present at close proximity, and detection is improved if the masker is spatially separated from the signal. A recent study has shown that, in frogs, spatial unmasking is more robust at the midbrain than at the periphery, indicating the importance of central mechanisms for this process. In this study, we investigated spatial unmasking patterns of single neurons in the frog inferior colliculus (IC) before and during iontophoretic application of bicuculline, a GABA(A) receptor antagonist. We found that drug application markedly decreased the strength of spatial unmasking such that even large angular separation of signal and masker sources produced only a weak masking release. Under the drug, the strength of spatial unmasking of midbrain neurons approximated that of auditory nerve fibers. These data show that GABAergic interactions in the auditory midbrain play an important role in spatial unmasking. Analysis of the effect of the drug on the direction sensitivity of the units shows that for the majority of IC units, bicuculline degrades binaural processing involved in directional coding, thereby compromising spatial unmasking. For other IC units, however, the decline in the strength of spatial unmasking is attributable to the effects of bicuculline on different central auditory processes.

Acoustic Stimulation↗
PubMed2004

[Statistical models for spatial analysis in parasitology].

The simplest way to study the spatial pattern of a disease is the geographical representation of its cases (or some indicators of them) over a map. Maps based on raw data are generally "wrong" since they do not take into consideration for sampling errors. Indeed, the observed differences between areas (or points in the map) are not directly interpretable, as they derive from the composition of true, structural differences and of the noise deriving from the sampling process. This problem is well known in human epidemiology, and several solutions have been proposed to filter the signal from the noise. These statistical methods are usually referred to as Disease Mapping. In geographical analysis a first goal is to evaluate the statistical significance of the heterogeneity between areas (or points). If the test indicates rejection of the hypothesis of homogeneity the following task is to study the spatial pattern of the disease. The spatial variability of risk is usually decomposed into two terms: a spatially structured (clustering) and a non spatially structured (heterogeneity) one. The heterogeneity term reflects spatial variability due to intrinsic characteristics of the sampling units (e.g. igienic conditions of farms), while the clustering term models the association due to proximity between sampling units, that usually depends on ecological conditions that vary over the study area and that affect in similar way breedings that are close to each other. Hierarchical bayesian models are the main tool to make inference over the clustering and heterogeneity components. The results are based on the marginal posterior distributions of the parameters of the model, that are approximated by Monte Carlo Markov Chain methods. Different models can be defined depending on the terms that are considered, namely a model with only the clustering term, a model with only the heterogeneity term and a model where both are included. Model selection criteria based on a compromise between degree of complexity and goodness of fit are then needed to discriminate among them, because each specification has a different biological meaning. Our aim is to demonstrate that these techniques can be used to study the geographical distribution of a parasite infection. Our analyses are based on data collected in 142 farms of the province of Latina. In each breeding a fixed number of sheeps has been sampled (20) and checked for the presence of C. daubneyi. We have specified a Binomial model for the proportion of infected animals in each breeding. The heterogeneity component is modelled in a standard way, while we have used different prior specifications for the clustering term to show how they affect the results. When we use the usual specification also for clustering, the two models show a completely different spatial pattern of infection, probably because the intrinsic spatial structure of the clustering term tend to bias our inferences. The selection criterion indicates in this case the heterogeneity model as the "best" one. However, if we modify the prior so that a lower degree of spatial interaction is assumed, the clustering model is less complex and its goodness of fit better and it should be preferred.

Animal Husbandry↗
PubMed2004

[Spatial structure of populations Myzus persicae and its predatory natural enemy Erigonidium graminicola].

In this paper, the spatial construction models of populations M. persicae and its predatory natural enemy E. graminicola during different periods were simulated by geostatistics, and their spatial relationships were analyzed. The spatial structure of M. persicae population was described by spherical model, showing an aggregated spatial arrangement. Its spatial dependence was 2.0252-4.1495 m, heterogeneity degree was 10,281.36-300,216.30, and sample variance was 12,176.81-303,433.70. The spatial structure of E . graminicola population was also simulated by spherical model, showing an aggregated spatial arrangement. Its spatial dependence was 3.7328-4.8983 m, heterogeneity degree was 1.4482-4.4134, and sample variance was 1.6941-5.8167. The results and methods could be applied to monitor the temporal and spatial dynamics of target insect pest population in tobacco field, and provide scientific basis for ecological control.

Animals↗
PubMed2006

[Spatial variability of farmland heavy metals contents in Qianan City].

By the methods of geostatistics and GIS, this paper studied the spatial variability of Cu, Zn, Ni, Cr As, Hg, Cd and Pb contents in the farmland topsoil (0 -20 cm) of Qianan City, Hebei Province. The results showed that the average contents of test metals were under the secondary standard of environmental quality standard for soil (GB 15618-1995), and belonged to moderate variability. The theoretical models of semi-variance of Cu, Zn, Ni, Cr and As contents fitted exponential models, and their spatial correlations were strongly spatial dependence; while the theoretical models of Hg and Cd contents fitted spherical models, and their spatial correlations were moderately spatial dependence. The Pb content had pure nugget effect, and was weakly spatial dependence. In whole research scale, Pb content had lasting variability, while the other seven heavy metals contents had the spatial variability mainly caused by their spatial correlation parts. The ranges of heavy metals spatial correlations were about 11 km to 20 km. The Kriging' s interpolation of Cu, Zn, Ni, Cr, Hg, As and Cd contents showed that their contents were higher in northern mountainous area, but lower in mid basin.

China↗
PubMed1990

Influence of monaural plugging on postnatal development of auditory spatial sensitivity of inferior collicular neurons of the big brown bat, Eptesicus fuscus.

Postnatal development of auditory sensitivity in the big brown bat, Eptesicus fuscus, was studied by determining the auditory spatial sensitivity of inferior collicular (IC) neurons of juvenile bats which were raised under normal (control) or monaurally plugged conditions. The auditory spatial sensitivity of each IC neuron was determined by measuring its variation in number of impulses and minimum threshold to a best frequency sound delivered from different azimuthal angles under free field stimulation conditions. Monaural plugging was performed on different juvenile bats at 7, 14, and 35 days of age. Auditory spatial sensitivity was then determined for IC neurons of monaurally plugged bats at 58-69 days after birth. Monaural plugging did not alter the discharge pattern, distribution of best frequency and latency of IC neurons, but it raised the minimum threshold of IC neurons of plugged juvenile bats by an average of 21-24 dB. Monaural plugging also appeared to modify postnatal development of auditory spatial sensitivity. The auditory spatial sensitivity of IC neurons was sharper when the earplug was intact than when the earplug was removed. Thus, the distribution of response center and the spatial sensitivity of IC neurons of the monaurally plugged bats was more comparable to IC neurons of the control bats before the earplug was removed. These findings suggest that the neural circuits underlying auditory spatial sensitivity of IC neurons of the monaurally plugged juvenile bats have undergone modifications to compensate for the unnatural binaural disparity during postnatal development. The auditory spatial sensitivity was also determined for two control juvenile bats at 49 and 60 days of age and for an adult bat (more than 1 year). Our data show that auditory spatial sensitivity of IC neurons sharpens with postnatal age. Furthermore, the sharpening process appears to be still in progress even at 60 days after birth.

Acoustic Stimulation↗
PubMed1988

Differential spatial displacement discrimination thresholds for Gabor patches.

Differential spatial displacement discrimination thresholds were determined for a configuration of three identical Gaussian modulated patches of sinusoidal grating presented with equal orientation and at threshold luminance contrast. The patches were arranged one above the other at equal spatial intervals. The orientation of the bars of the sinusoidal grid constituting the patches was orthogonal to the axis joining the centres of the outer two patches. Thresholds were determined for displacements of the middle patch both orthogonal to and along the axis joining the outer two patches. Thresholds for both tasks were obtained as a function of both the spatial frequency of the sinusoidal grating and the spatial scale parameter of the Gaussian envelope of the patches. We found that the differential spatial displacement discrimination thresholds for both tasks are a constant fraction of the spatial scale parameter of the Gaussian envelope of the sinusoidal grating patches and are independent of the spatial frequency of the modulated grating. We conclude that the human visual system is capable of assigning a single location tag to an entire Gaussian modulated patch of sinusoidal grating. The accuracy with which the relative position of such a Gabor patch can be determined in a constant fraction of its spatial extent (spread of the Gaussian spatial envelope).

Adult↗
PubMed1987

Spatial and temporal selectivity in the suprasylvian visual cortex of the cat.

We recorded from single units in the medial and lateral banks of the posterolateral suprasylvian visual cortex (PMLS/PLLS) of the cat. The responses to drifting high-contrast gratings of optimum orientation and direction of motion, but varying in spatial and temporal frequency, were examined quantitatively for a sample of cells, whose receptive fields covered a wide range of eccentricities. The optimum spatial frequencies (average about 0.2 cycles/deg) were low compared to the values reported for striate cortex but similar to those for area 18. The mean spatial bandwidth (about 2 octaves) was slightly broader than that of cells in other cortical visual areas. The cut-off spatial frequencies ("acuities") covered a wide range, from 0.05 to 2.1 cycles/deg, similar to those of cells in area 18. Responses to drifting sinusoidal gratings were usually dominated by an unmodulated elevation of discharge, although some modulation occurred at the temporal frequency of drift, especially at low spatial frequencies. Modulated responses were relatively stronger in PMLS than in PLLS. For those cells that responded to flashed stimuli, stationary, contrast-modulated gratings presented at different spatial positions typically evoked small responses at the fundamental frequency (dependent on spatial phase) and a larger component at the second harmonic of temporal frequency, with no overall "null-position." The optimum spatial frequency was usually higher than would be predicted by simple summation within the dimensions of the receptive field. Thus, neurons in PMLS and PLLS, like complex cells in areas 17 and 18, behave nonlinearly and their spatial selectivity is determined by "subunits" smaller than their receptive fields. The range of preferred temporal frequencies ranged from less than 2.5 Hz to more than 10 Hz. In their temporal selectivity neurons in PMLS resembled cells in area 17, with little attenuation at low temporal frequencies, whereas there was a tendency for cells in PLLS to prefer higher temporal frequencies, as is common in area 18.

Animals↗
PubMed1994

Inhibition of nitric oxide synthase does not impair spatial learning.

Nitric oxide (NO), a putative intercellular messenger in the CNS, may be involved in certain forms of synaptic plasticity and learning. This article reports a series of experiments investigating the effects of N omega-nitro-L-arginine methyl ester (L-NAME) upon various forms of learning and memory in the watermaze. L-NAME (75 mg/kg, i.p., sufficient to bring about > 90% inhibition of NO synthesis in brain) produced an apparent impairment in spatial learning when given to naive rats during acquisition (3 d, six training trials per day). This impairment was dose related, stereoselective, and attenuated by coadministration of L-arginine. A second study showed that L-NAME did not affect the retention of a previously learned spatial task. In addition, in a visual discrimination task, the rate at which criterion levels of performance were reached was unaffected by L-NAME. Thus, inhibition of NO synthase may cause a selective impairment of spatial learning without effect upon retention. However, analysis of the early training trials of the visual discrimination task revealed significantly elevated escape latencies in the L-NAME-treated rats, suggesting that inhibition of NO synthase may have more general effects. As normal rats learn the spatial task very rapidly, the possibility arises that the apparent deficit in learning is due to a disruption of some process other than learning per se. A further series of experiments investigated this possibility. L-NAME was found not to impair the learning of a new platform position in the same spatial environment. Surprisingly, L-NAME also had no effect on spatial learning in a second watermaze located in a novel spatial environment by rats well practiced with all aspects of watermaze training. Finally, L-NAME had no effect on spatial learning in naive rats trained with just one trial per day. Thus, systemic injection of an NO synthase inhibitor impairs behavioral performance in two tasks during their initial acquisition, but the basis of this functional disruption is unlikely to be due to any direct effect upon the mechanisms of spatial learning.

Amino Acid Oxidoreductases↗
PubMed1998

Where and when to pay attention: the neural systems for directing attention to spatial locations and to time intervals as revealed by both PET and fMRI.

Although attention is distributed across time as well as space, the temporal allocation of attention has been less well researched than its spatial counterpart. A temporal analog of the covert spatial orientation task [Posner MI, Snyder CRR, Davidson BJ (1980) Attention and the detection of signals. J Exp Psychol Gen 109:160-174] was developed to compare the neural systems involved in directing attention to spatial locations versus time intervals. We asked whether there exists a general system for allocating attentional resources, independent of stimulus dimension, or whether functionally specialized brain regions are recruited for directing attention toward spatial versus temporal aspects of the environment. We measured brain activity in seven healthy volunteers by using positron emission tomography (PET) and in eight healthy volunteers by using functional magnetic resonance imaging (fMRI). The task manipulated cued attention to spatial locations (S) and temporal intervals (T) in a factorial design. Symbolic central cues oriented subjects toward S only (left or right), toward T only (300 msec or 1500 msec), toward both S and T simultaneously, or provided no information regarding S or T. Subjects also were scanned during a resting baseline condition. Behavioral data showed benefits and costs for performance during temporal attention similar to those established for spatial attention. Brain-imaging data revealed a partial overlap between neural systems involved in the performance of spatial versus temporal orientation of attention tasks. Additionally, hemispheric asymmetries revealed preferential right and left parietal activation for spatial and temporal attention, respectively. Parietal cortex was activated bilaterally by attending to both dimensions simultaneously. This is the first direct comparison of the neural correlates of attending to spatial versus temporal cues.

Adult↗
PubMed2026

Accurately Deciphering Tissue Heterogeneity From Spatial Multi-Modal and Multi-Omics With STransformer.

Advances in spatially resolved technologies enable the simultaneous acquisition of diverse data modalities within a tissue slice while preserving critical spatial context, which presents unprecedented opportunities to decipher intricate tissue heterogeneity. However, existing computational approaches lack the intrinsic flexibility to universally process both spatial multi-modal and multi-omics data. Here, we introduce STransformer, a unified deep learning framework designed to seamlessly accommodate a comprehensive landscape of spatial data. By simultaneously capturing short-range cellular interactions and tissue-wide semantic patterns, it extracts robust representations to accurately dissect complex tissue heterogeneity. Systematic evaluations across diverse species, tissue types, and data modalities highlight its profound versatility. For spatial multi-modal data, STransformer delineates intricate anatomical structures in the human cortex, uncovers pathological mechanisms in Alzheimer's disease, and characterizes dynamic spatiotemporal developmental trajectories during chicken cardiogenesis. Scaling to spatial multi-omics data, STransformer synergizes spatial transcriptomic and proteomic profiles to decipher intricate immune microenvironments within the human tonsil, and jointly analyzes spatial epigenomic and transcriptomic data to infer regulatory mechanisms in the mouse embryonic brain. Consequently, STransformer serves as a highly versatile and robust analytical framework for advancing our understanding of tissue heterogeneity and disease pathogenesis.

Multiomics↗
PubMed1994

Sexually dimorphic spatial learning varies seasonally in two populations of deer mice.

Spatial learning in photoperiodically induced breeding (reproductive) and non-breeding (non-reproductive) adult male and female deer mice (Peromyscus maniculatus) was examined in a Morris water-maze task. Sexually mature, adult male and female deer mice that were derived from either a mainland population (P. m. artemisiae) or an island population (P. m. angustus) were required to learn the spatial position of a hidden, submerged platform in a water maze. Deer mice were tested either during the breeding season (summer; long day photoperiod) or during the non-breeding season (winter; short day photoperiod) with a total of six blocks of four trials conducted in a single day. Retention was tested with two probe trials which occurred one and three days after acquisition. During the breeding season male spatial task acquisition was superior to female spatial task acquisition for both populations. In contrast, during the non-breeding season there were no significant sex differences in spatial acquisition for either population. This change in sexually dimorphic spatial learning was due to female spatial-performance decreasing from non-breeding season to the breeding season and male spatial-performance increasing over the same period. Both populations displayed similar seasonal variations in sexually dimorphic water-maze task performance. There were, however, overall population differences in water-maze task performance that were related to the ecology of the mice, with the insular mice displaying shorter latencies to reach the hidden platform than did the mainland deer mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Heterosis and resistance to DFP effects on spatial learning in C57BL X DBA hybrids.

The inbred mouse strains C57BL/6Ibg and DBA/2Ibg differ in their ability to exhibit spatial learning in the Morris water task. C57BL mice learn the task well and show impairment of spatial learning following disruption of cholinergic function. DBA mice show rudimentary spatial learning ability, and are not further impaired when cholinergic function is decreased. These mice may carry genes regulating a noncholinergic spatial learning system. To test this hypothesis, first generation (F1) hybrids between DBA and C57BL mice were tested for spatial learning in the Morris water task. The hybrids performed better than either parental strain, suggesting that both parents contributed genes for spatial learning ability. Chronic treatment with diisopropylfluorophosphate (DFP), which abolished spatial learning ability in C57BL mice, produced only minor impairments in the hybrids. The behavioral resistance to DFP occurred despite significant reductions in hippocampal and cortical muscarinic binding. The results suggest either that the hybrids inherited a noncholinergic neurochemical system influencing spatial learning from their DBA parents or that the DFP treatment did not disrupt cholinergic function to a sufficient degree to impair the superior learning abilities of the F1 hybrids.

Acetylcholinesterase↗
PubMed2005

Metabotropic glutamate receptor 1 blockade impairs acquisition and retention in a spatial Water maze task.

Metabotropic glutamate receptors, including the mGlu1 receptor, have received considerable attention as potential targets for anxiolytic, antidepressant, antipsychotic and antinociceptive drugs. mGlu1 receptors have also been suggested to play a role in the modulation of cognitive processes, but knowledge is still very limited. In the present study the effects of the selective mGlu1 receptor antagonist 3,4-dihydro-2H-pyrano[2,3]beta-quinolin-7-yl)(cis-4-methoxycyclohexyl)methanone (JNJ16259685, 0.63-10 mg/kg s.c.) on more or less spatially demanding learning and spatial memory (retention and re-acquisition) were investigated in mice performing in a water maze. Selective mGlu1 receptor blockade with JNJ16259685 impaired spatial acquisition processes, irrespective of spatial load, as well as spatial re-acquisition, already at the lowest dose tested (0.63 mg/kg). In contrast, effects on spatial retention performance were relatively mild in mice that had learned to locate the position of the escape platform prior to treatment. Thigmotaxic behaviour and locomotor activity appeared to be unaffected by JNJ16259685. These data suggest that blockade of the mGlu1 receptor primarily affects learning of new information, but leaves retention of spatial information relatively unaffected. Blockade of the mGlu5 receptor with MPEP also impaired spatial learning, although only at the highest dose tested (10 mg/kg). An ex vivo receptor occupancy study in rats revealed that MPEP occupied central mGlu5 receptors with an ED(50) of 2.0 mg/kg one hour after subcutaneous administration. This is 50-150 times higher than the ED(50) reported for JNJ16259685 at central mGlu1 receptors and suggests that one reason why the two compounds cause cognitive effects at different doses might be due to differences in central mGlu receptor occupancy, rather than fundamentally different roles of mGlu1 and mGlu5 receptors in the modulation of cognitive function.

Animals↗
PubMed2003

Detailed behavioral analysis reveals both task strategies and spatial memory impairments in rats given bilateral middle cerebral artery stroke.

Middle cerebral artery occlusion (MCAO) impairs performance in the water maze task by rats. The purpose was to evaluate the effect of bilateral MCAO in naive and strategies-pretrained rats using a detailed behavioral analysis to further develop a water maze model of stroke. Rats were trained in either a simple swim-to-visible platform task or in a conventional spatial version with a hidden platform in the pool. In the visible platform task naive stroked rats were impaired because of a marked tendency to swim thigmotaxically on most trials. For the spatial learning experiment, some rats received Morris' water maze strategies pretraining prior to MCAO and subsequent spatial training to familiarize them with the general behavioral strategies required in the task. In the spatial learning task naive stroked rats had both strategies and spatial learning impairments but pretrained stroked rats were indistinguishable from sham controls on all behavioral measures. All stroked rats had comparable bilateral brain damage measured using a computerized volumetric measuring technique. These results indicate that in naive rats bilateral MCAO causes behavioral strategies impairments in the visible and hidden platform versions of the water maze as well as specific spatial learning impairments in the hidden platform version. The results also indicate that behavioral strategies pretraining allows stroked rats to acquire and remember sufficient strategies skills and spatial information to perform as well as sham controls during subsequent spatial training. These techniques appear to be capable of quantifying the effects of potentially protective treatments for stroke.

Adaptation, Psychological↗