Hippocampal place cells fire selectively when a rat occupies a particular location. Under certain conditions, the cells briefly represent trajectories along locations away from the rat's current location. New results lend important insight into this phenomenon and demonstrate spatiotemporally coherent, cognitive representations that are independent of current sensory input.

ABSTRACTIntroduction: Previous investigations have shown that protein malnutrition can alters the structure and function of some areas of hippocampal formation. We investigated the effect of protein malnutrition on amygdaloid projections to the CA1 hippocampal area. In this study we investigated level and pattern of distribution of efferent projections from amygdala to hippocampus in the rat by...

The activity of hippocampal pyramidal cells reflects both the current position of the animal and information related to its current behavior. Here we investigated whether single hippocampal neurons can encode several independent features defining trials during a memory task. We also tested whether task-related information is represented by partial remapping of the place cell population or, inst...

Integrins are a diverse family of heterodimeric (alphabeta) adhesion receptors recently shown to be concentrated within synapses and involved in the consolidation of long-term potentiation. Whether neuronal types or anatomical systems in the adult rat brain are coded by integrin type was studied in the present experiments by mapping the relative densities of mRNAs for nine alpha and four beta s...

introduction: repetitive cortical spreading depression (csd) can lead to cell death in immature brain tissue. caspases are involved in neuronal cell death in several csd-related neurological disorders. yet, whether repetitive csd itself can induce caspase activation in adult or juvenile tissue remains unknown. inducing repetitive csd in somatosensory cortices of juvenile and adult rats in vivo,...

During periods of stress, cells depend on a transient, highly conserved, and regulated response to maintain homeostasis. This "heat shock response" is mediated transcriptionally by a multigene family of heat shock factors (HSF). The presence of multiple HSF suggests that activation of a given HSF is stress-specific. Using Western blot analysis, we have demonstrated the inability of primary cult...

Adult hippocampal neurogenesis, the constitutive generation of new granule cells in the dentate gyrus of the mature brain, is a robust model of neural development and its dysregulation has been implicated in the pathogenesis of psychiatric and neurological disorders. Previous studies in mice have shown that altered expression of Disrupted-In-Schizophrenia 1 (Disc1), the mouse homolog of a risk ...

A model of the hippocampus as a central element in rat navigation is presented. Simulations show both the behaviour of single cells and the resultant navigation of the rat. These are compared with single unit recordings and behavioural data. The firing of CAl place cells is simulated as the (artificial) rat moves in an environment. This is the input for a neuronal network whose output, at each ...