Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Spatial Behavior”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,513 records · Page 84Linked to original sources
PubMed1989

Language, modality and the brain.

Studies of the signed languages of deaf people have shown that fully expressive languages can arise, outside of the mainstream of spoken languages, that exhibit the complexities of linguistic organization found in all spoken languages. Thus, the human capacity for language is not linked to some privileged cognitive-auditory connection. However, the formal properties of languages (spoken or signed) appear to be highly conditioned by the modalities involved in their perception and production. Multi-layering of linguistic elements and the use of space in the service of syntax appear to be modality-determined aspects of signed languages. Analyses of patterns of breakdown of signed languages provide new perspectives on the nature of cerebral organization for language. The studies reviewed in this article show that the left cerebral hemisphere in man is specialized for signed as well as spoken languages, and thus may have an innate predisposition for language, independent of language modality.

Adult↗
PubMed1981

Cognitive mapping in rats: the role of the hippocampal and frontal system in retention and reversal.

These experiments determined the extent to which the hippocampal system and the medial frontal cortex are selectively involved in cognitive mapping in spatial environments. Rats were trained to discriminate between two 3-dimensional objects based on either the location of the objects in the test environment, or on the stimulus characteristics of the objects themselves. Following the acquisition of one of these discrimination tasks, each rat was given a series of transfer tests to determine the extent to which a cognitive mapping strategy had been used to solve the task. Each rat was then given a lesion in the fimbria-fornix or the medial frontal cortex, or a control operation. In the location discrimination, rats with fimbria-fornix lesions, as compared to control rats: (a) performed poorly at the beginning of retention testing; (b) relearned the task to criterion performance; (c) performed normally during the transfer tests indicating that they used a cognitive mapping strategy, and (d) performed poorly in the discrimination reversals. In the object discrimination, these rats performed as well as controls during retention and transfer tests, but had a slight impairment during discrimination reversals. The performance of rats with lesions in the medial frontal cortex was worse than that of the controls during the retention of both discriminations, and during the reversal of the location, but not the object discrimination. These results are related to predictions of current theories implicating the hippocampus and medial frontal cortex in spatially organized behaviors, particularly those behaviors requiring cognitive mapping.

Animals↗
PubMed1982

Selective effects of hippocampal and frontal cortex lesions on a spatial learning problem in two inbred strains of mice.

The effects of dorsal hippocampal and medial frontal lesions of the cortex on a spatial learning problem were studied in two inbred strains of mice (C57BL/6 and DBA/2) which present both neuroanatomical differences of such structures and various patterns of spontaneous exploration. The results showed that hippocampal lesions produced impairments of the learning performance in each strain of mouse, but the temporal distribution of the errors over the experiment was found to be strain dependent. On the other hand, medial frontal cortex lesions selectively affected the learning performances since the acquisition process of only the C57BL/6 lesioned mice differed significantly from the other groups. The effects of these lesions are discussed in terms of genetically associated differences of brain structures and functions. It is suggested that investigations of such differences can provide an experimental model for the study of functional and structural recovery.

Animals↗
PubMed1983

Hippocampectomy selectively disrupts discrimination reversal conditioning of the rabbit nictitating membrane response.

The effects of hippocampal lesions were tested on two-tone discrimination reversal conditioning of the rabbit nictitating membrane response. Results showed that hippocampectomized animals learned the initial two-tone discrimination at rates equivalent to operated control animals and animals with neocortical lesions. During reversal conditioning, however, animals with hippocampal lesions were severely impaired relative to both other groups. Neocortical lesions were without effect on reversal learning. An additional study revealed that the hippocampectomized animals' failure at reversal could not be attributed to a lesion-induced increased resistance to extinction. Results are discussed with respect to several theories of hippocampal function, and with respect to changes in the activity of hippocampal pyramidal neurons which occur during classical conditioning of the nictitating membrane response.

Animals↗
PubMed1983

A behavioural analysis of spatial localization following electrolytic, kainate- or colchicine-induced damage to the hippocampal formation in the rat.

This experiment examines the notion that in the rat the hippocampal formation is an essential structure in the neurological representation of spatial abilities. Spatial localization by rats with different types of hippocampal damage, including bilateral electrolytic lesions, unilateral and bilateral kainic acid-induced CA3-CA4 lesions, and unilateral and bilateral colchicine-induced dentate gyrus lesions, was compared with vehicle-injected and normal control groups in the Morris water task. The task required the rats to escape from cold water by finding a submerged and hidden platform located at a fixed place within the room. The start point was varied randomly from trial to trial and there were no local cues available to indicate the position of the hidden platform. After training, the platform was moved. Escape latencies and the initial swimming headings revealed that all lesion groups, except the unilateral CA3-damaged group, were impaired at finding the platform: the dentate-damaged rats exhibited the greatest deficit. When the platform was moved the control rats swam mainly in the part of the pool that had previously contained the platform and, on finding it in the new location, they showed a marked dishabituation of rearing. None of the bilateral lesion groups showed these effects.

Animals↗
PubMed1985

Spatial learning and memory, maze running strategies and cholinergic mechanisms in two inbred strains of mice.

The acquisition process of the radial maze task was studied in two inbred strains of mice, C57BL/6 and DBA/2. A quantitative and qualitative evaluation of performance was performed and the pretest level of activity was measured. The results showed a significant correlation between activity and performance since the highly active C57BL/6 mice exhibited better performance of the radial maze task than the less active DBA/2 mice. Moreover, for correct trials, strain-dependent maze-running strategies were observed: while both strains displayed about the same percentage of clockwise and spatial strategies, it was observed that among the spatial strategies C57BL/6 used a larger number of different correct solutions. Subsequently, the effect of scopolamine administration on working memory processes was assessed in sequential and discrete trials. A different reactivity of each strain to anti-cholinergic treatment was found in discrete trials since only DBA/2 mice were impaired. The effect of scopolamine is discussed in relation to the different models of information processing involved in learning and memorizing the experimental rule.

Animals↗
PubMed1986

Interocular transfer of learning in the pigeon: visuo-motor integration and separation of discriminanda and manipulanda.

Interocular transfer (IOT) of visual information in pigeons has been shown to vary according to the training paradigm. In the present experiment 6 groups of pigeons were trained on a color discrimination using 6 different training paradigms. It was found that a successive discrimination with a single key and a simultaneous discrimination with either two keys arranged horizontally or with two keys arranged vertically, all produced successful interocular transfer of learning. On the other hand, the other 3 training paradigms, in which the discriminative stimulus was presented on 'stimulus key' and the pecking response was made by a separate 'response key', all failed to show IOT. The geometric relationship between the stimulus key and the response key (upper, lower or side) does not appear to be crucial. Thus, the spatial separation of the response key and the stimulus key produced the failure of interocular transfer. These results support the idea that visuo-motor integration has the most important role in descrepancy of results of the pigeon's IOT experiments.

Animals↗
PubMed1986

Interactions between response stereotypy and memory strategies on the eight-arm radial maze.

Three groups of water-deprived rats collected water from the ends of the 8-arm radial maze. Sighted subjects, and subjects blinded either with or without pre-enucleation experience on the radial maze, all retrieved the water efficiently. Most of the subjects exhibited the same response stereotypy, regularly choosing 8 adjacent arms of the maze, then stopping in the center of the maze. The strategies underlying this performance were analysed by interrupting trials and rotating the maze 180 degrees after the subject had made 3 choices. Sighted subjects depended on extramaze stimuli, naive-blind subjects depended on intramaze stimuli and experienced-blind subjects ignored their initial 3 choices after the trial was interrupted. Choice accuracy was equally good whether the subject was returned to the position from which it had been removed, or returned to the opposite side of the central platform. All 3 groups of subjects maintained their stereotyped adjacent-arm responding only as long as such responding was consistent with high choice accuracy. Response stereotypy was prevalent on the radial maze, but response strategies were secondary to memory strategies.

Animals↗
PubMed1987

Chlordiazepoxide, an anxiolytic benzodiazepine, impairs place navigation in rats.

There are separate proposals that the hippocampus is involved in 'spatial memory' and in the control of 'anxiety'. Despite a larger number of common effects of anxiolytic drugs and hippocampal lesions, no effect of anxiolytic drugs has yet been reported in those spatial tasks which are particularly sensitive to the effects of hippocampal lesions. The present study addresses this issue. Separate groups of rats were treated, i.p., with 5 mg/kg chlordiazepoxide (an anxiolytic benzodiazepine), 1 mg/kg scopolamine (a muscarinic antagonist which has previously been shown to impair spatial learning) and a saline placebo. They were then trained to find a platform which was hidden in a constant location just under the surface of opaque water in a swimming pool. Separate groups of rats were trained with 4 trials per day and with 1 trial per day. Number of trials per day did not significantly influence the effects of the drugs. Chlordiazepoxide and scopolamine produced similar degrees of impairment in spatial learning to each other--but less impairment than has previously been reported with hippocampal lesions. The effectiveness of the anxiolytic drug chlordiazepoxide in the swimming pool, a specifically spatial task, suggests that the opposing concepts of 'spatial memory' and 'anxiety' which have been used previously to describe hippocampal function may represent different aspects of a unitary concept.

Animals↗
PubMed1987

Hippocampal, granule cell and CA3-4 lesions impair formation of a place learning-set in the rat and induce reflex epilepsy.

Rats were pretrained on a place learning-set task, in which a platform, submerged in a swimming pool filled with opaque water, was moved to a new location each day. Then they received either: suction removal of the dorsal hippocampus, intrahippocampal microinjections of colchicine to remove dentate gyrus granule cells, kainic acid to remove CA3-4 cells of the hippocampus proper, suction removal of parietal cortex overlying the hippocampus, or no surgery. Performance was then evaluated for 48 days. All lesion groups were chronically impaired with respect to the control group, but the rats with parietal cortex lesions retained the ability to solve the task, whereas rats with hippocampal damage did not. Training frequently induced task-related behavioural seizures in the rats with granule cell or CA3-4 lesions. The results show that the hippocampus, including granule cell and CA3-4 cell populations, is essential for the rapid acquisition of place responses in the swimming pool task. The finding that training on the task induced reflex epilepsy in granule cell and CA3-4-damaged rats, but not those with aspirative removals, suggests that residual portions of the hippocampus are activated by training and are involved in production of the epileptic attacks.

Animals↗
PubMed1988

Right-left asymmetry in position learning of male chicks.

Two-week-old chicks were trained to discriminate between two identical boxes on the basis of their position. The positive box was placed against the wall facing the entrance of the test cage, whereas the negative box was placed either on the right or on the left wall. Results showed that male chicks learned the task faster when the negative box was placed on the right than when it was placed on the left, whereas no right-left asymmetry appeared in females.

Animals↗
PubMed1995

8-OH-DPAT impairs spatial but not visual learning in a water maze by stimulating 5-HT1A receptors in the hippocampus.

The effect of 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), a 5-HT1A receptor agonist, on spatial and non-spatial learning in a water maze was studied using two tasks of equal difficulty, with the same motor, motivational and reinforcement demands. Rats were examined for choice accuracy in a two-platform spatial discrimination task. Rats treated subcutaneously with 100 micrograms/kg 8-OH-DPAT were impaired in choice accuracy with no effect on latency. Treated rats made more errors of omission than controls only on days 1 and 2 of training. Infusion of 1 microgram/microliter spiroxatrine (SPX) or 5 micrograms/microliters of (+)WAY100135, two potent 5-HT1A receptor antagonists, in the CA1 region of the dorsal hippocampus antagonized the impairment in choice accuracy caused by 8-OH-DPAT. The effect on errors of omission on days 1 and 2 of training were not significantly modified by spiroxatrine or (+)WAY100135. Rats treated with 8-OH-DPAT were not impaired in their ability to learn a visual discrimination in a water maze. The results suggest that stimulation of 5-HT1A receptors in the CA1 region of the dorsal hippocampus impairs spatial but not visual discrimination in rats.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1995

Relational object association learning in rats with hippocampal lesions.

The contribution of the hippocampus to relational association learning was examined using a paired associate task in the rat. Using a go/no-go paradigm, rats were trained to respond quickly on positive pair presentations, and to withhold responding on negative pair presentations. Using four constant three-dimensional objects (A, B, C and D), pairing of either AB or CD was assigned as positive pairs, whereas the other possible object combinations (AC, DB, AD, and CB) were never associated with reinforcement. A further type of negative pair trial was also studied which involved object-pairs composed of one of the four constant objects and another object, which varied from trial, and which was selected from a set of 120 junk objects. Electrolytic lesions of the hippocampus were performed on the rats which had previously acquired the paired associate task. Results indicated that hippocampal lesions did not significantly impair the ability of the animals to solve the paired associate task. To study further the exact nature of the learned associations, a transfer test which involved a reversal of the spatial position within each of the six positive as well as negative pair-types was conducted. Results of the transfer test demonstrated that hippocampal-lesioned as well as control rats performed normally by distinguishing the positive from negative pairs regardless of the relative location of stimuli within the object pairs. These data suggest that the hippocampus might not be critical for relational object associations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

EEG activity during cognitive processing: influence of attentional factors.

The research draws upon two separate areas of inquiry: that of lateralized electrocorical processing of cognitive material; and that of psychophysiological information processing studies related to foci of attentional demands. Eighteen subjects on each of three separate days were presented with tasks considered to be 'right hemispheric' or 'left hemispheric'. These tasks were paired in a 2 X 2 design with an attentional factor requiring attention to the environment or to internal processing. All subjects received all types of tasks. Bilateral EEG measures were taken from the frontal and parietal areas referenced to linked ears. Major frequency bands were determined by a Fast Fourier Transform (FFT) and appropriate ANOVAs performed. The results suggest that task factors (left vs right hemisphere tasks) and attentional demands (internal vs external) are differentially represented in terms of EEG functioning. In general the higher beta frequencies were more sensitive to the hemispheric tasks demands and the middle frequencies (alpha and low beta) more sensitive to the attentional demands especially in the parietal areas.

Alpha Rhythm↗
PubMed1996

Influence of the initial projection of the centre of gravity on posturo-kinetic coordination in humans. Application from a horizontal quadrupedal stance during voluntary limb raising.

The purpose of the study is to investigate the influence of initial projection of the centre of gravity (CG) on the spatial and temporal organization of the dynamic phenomena accompanying a voluntary movement in humans. From a horizontal quadrupedal stance, ten normal subjects were instructed to raise the right forelimb towards a support target in self paced velocity conditions. Three experimental conditions were tested for which the initial CG projection was either within (C1), at the limits of (C2) or outside the supporting triangle (C3). The results showed that vertical force variations on the four supports always preceded the first vertical displacement of the right wrist (onset of the movement). From C1 to C3, the duration of these anticipatory dynamic phenomena increased enabling an adjustment of the CG position such that equilibrium constraints were fulfilled. For all conditions, the acceleration peak of the CG occurred prior to the onset of movement and from C1 to C3, its magnitude increased in a single direction of the horizontal plane. For each condition, the load transfer was directed to the left forelimb and the right hindlimb (diagonal strategy) and reached a maximal value at the time of lift-off. With respect to this moment, the onset of the movement occurred increasingly early from C1 to C3. These results suggest that contribution of peripheral cues to postural control is more important, when the requirements of horizontal CG displacement increase.

Adult↗
PubMedDate not supplied

The ACTH/MSH (4-9) analog Org2766 improves retrieval of information after a fimbria fornix transection.

The fimbria fornix of male Wistar rats was transected unilaterally after they had been successfully trained in the Morris maze and the passive avoidance task. Sham-operated and lesioned animals were treated either with Org2766 or saline for two weeks. Subsequently, the performance of all groups was tested again starting two days after the last treatment. The lesioned animals showed a deficit in performance in both tasks, indicating interference of the lesion with retrieval of information. Org2766 improved the poor performance of the lesioned animals in the Morris maze, but not in the passive avoidance task.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Vasoactive intestinal peptide (VIP): an amnestic neuropeptide.

Vasoactive intestinal peptide (VIP) is a neuropeptide present in high concentrations in the hippocampus. The studies reported here demonstrate that VIP administered into the third ventricle of the brain caused amnesia in mice trained on a left-right footshock avoidance task in a T-maze. VIP resulted in amnesia when administered directly into the rostral portion of the hippocampus at a 10-fold lower dose than was needed to produce amnesia when VIP was administered intracerebroventricularly. When VIP was administered 24 hr after training, it failed to impair retention measured a week later. VIP receptor antagonist ([4-Cl-D-Phe6,Leu17]VIP) enhanced retention when administered into the rostral portion of the hippocampus, suggesting that VIP plays a physiological role in memory modulation. VIP receptor antagonist administered 24 hr after training did not facilitate retention. To gain some insight as to how VIP may be affecting memory processing, we determined if some memory-improving compounds showed a selective ability to block amnesia induced by VIP. The amnestic effect of VIP was blocked by peripheral administration of the memory-enhancing agents, arecoline, naloxone and ST 587 (a noradrenergic receptor agonist) but not by cholecystokinin octapeptide. Central administration of arecoline, but not neuropeptide Y, blocked the amnestic effect of VIP. It is concluded that VIP is a potent amnestic peptide.

Amnesia↗