objective(s): there is controversial evidence about the effect of methamphetamine (meth) on spatial memory. we tested the time- dependent effects of meth on spatial short-term (working) and long-term (reference) memory in meth –sensitized and withdrawn rats in the morris water maze. materials and methods: rats were sensitized to meth (2 mg/kg, daily/5 days, sc). rats were trained in water maze ...

The activation of cAMP-responsive element-binding protein (CREB)-dependent gene expression is thought to be critical for the formation of different types of long-term memory. To explore the consequences of chronic enhancement of CREB function on spatial memory in mammals, we examined spatial navigation in bitransgenic mice that express in a regulated and restricted manner a constitutively activ...

Damage to the medial temporal lobes produces profound amnesia, greatly impairing the ability of patients to learn about new associations and events. While studies in rodents suggest a strong link between damage to the hippocampus and the ability to navigate using distal landmarks in a spatial environment, the connection between navigation and memory in humans remains less clear. Past studies on...

For years, the debate has been: "Is the hippocampus the cognitive map?" or "Is the hippocampus the core of memory?" These two hypotheses derived their original power from two key experiments--the cognitive map theory from the remarkable spatial correlates seen in recordings of hippocampal pyramidal cells and the memory theory from the profound amnesias seen in the patient H.M. Both of these key...

Environments that are divided into regions lead to hierarchical encoding of space. Such memory structures are known to systematically distort estimates of distance and direction and affect spatial priming and memory recall. Here we present two navigation experiments in virtual environments that reveal an influence of environmental regions on human route planning and navigation behaviour. Follow...

The brain-derived neurotrophic factor (BDNF) was shown to be involved in spatial memory and spatial strategy preference. A naturally occurring single nucleotide polymorphism of the BDNF gene (Val66Met) affects activity-dependent secretion of BDNF. The current event-related fMRI study on preselected groups of 'Met' carriers and homozygotes of the 'Val' allele investigated the role of this polymo...

Thalamic neurons that signal an animal's direction of heading are crucial for spatial navigation. Both directional coding and flexible use of spatial memory are upended, however, when a rat has to find its way while upside down.

Ketamine, a non-competitive N-methyl-d-aspartate receptor antagonist, is rising in popularity as a drug of abuse. Preliminary evidence suggests that chronic, heavy ketamine use may have profound effects on spatial memory but the mechanism of these deficits is as yet unclear. This study aimed to examine the neural mechanism by which heavy ketamine use impairs spatial memory processing. In a samp...

OBJECTIVES Cognitive deficit is considered to be a characteristic feature of schizophrenia disorder. A similar cognitive dysfunction was demonstrated in animal models of schizophrenia. However, the poor comparability of methods used to assess cognition in animals and humans could be responsible for low predictive validity of current animal models. In order to assess spatial abilities in schizop...

SPATIAL MEMORY IS MAINLY STUDIED THROUGH THE VISUAL SENSORY MODALITY: navigation tasks in humans rarely integrate dynamic and spatial auditory information. In order to study how a spatial scene can be memorized on the basis of auditory and idiothetic cues only, we constructed an auditory equivalent of the Morris water maze, a task widely used to assess spatial learning and memory in rodents. Pa...