Eletrical recordings will be made from single neurons from different parts of the hippocampal formation (Ammon's horn, dentate gyrus, subiculum, presubiculum, postsubiculum, parasubiculum, medial and lateral entorhinal cortex and perirhinal cortex) in freely moving rats quantitatively analyzed with a TV-computer based system. In the tasks whichl will be used, neurons from some of these regions are known to fire when the rat is at a specific location or when the rat's head is pointing a specific direction, or some combination of location and direction, i.e., to signal information necessary for some kinds of navigation. From what is known already, the flow and transformation of navigational information can be partially sketched out. By recording from more regions, this flow and transformation should become much clearer. A new task will be introduced in which rats will move between two different environments. This task is designed to especially test the control of head directional firing across environments. Almost nothing is known about the neuronal mechanisms of navigation. The ability to navigate is often lost in dementia, and is an especially serious deficit because the people get lost. Navigation is complex non verbal cognition, and the problem of cellular analysis of flow and transformation of representations in this cognitive process seems solvable.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
2R01NS014497-13
Application #
3395570
Study Section
Biopsychology Study Section (BPO)
Project Start
1978-04-01
Project End
1995-02-28
Budget Start
1991-03-01
Budget End
1992-02-29
Support Year
13
Fiscal Year
1991
Total Cost
Indirect Cost
Name
Suny Downstate Medical Center
Department
Type
Schools of Medicine
DUNS #
068552207
City
Brooklyn
State
NY
Country
United States
Zip Code
11203
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Muller, R U; Ranck Jr, J B; Taube, J S (1996) Head direction cells: properties and functional significance. Curr Opin Neurobiol 6:196-206
Muller, R U; Bostock, E; Taube, J S et al. (1994) On the directional firing properties of hippocampal place cells. J Neurosci 14:7235-51
Quirk, G J; Muller, R U; Kubie, J L et al. (1992) The positional firing properties of medial entorhinal neurons: description and comparison with hippocampal place cells. J Neurosci 12:1945-63
Quirk, G J; Muller, R U; Kubie, J L (1990) The firing of hippocampal place cells in the dark depends on the rat's recent experience. J Neurosci 10:2008-17
Taube, J S; Muller, R U; Ranck Jr, J B (1990) Head-direction cells recorded from the postsubiculum in freely moving rats. I. Description and quantitative analysis. J Neurosci 10:420-35
Taube, J S; Muller, R U; Ranck Jr, J B (1990) Head-direction cells recorded from the postsubiculum in freely moving rats. II. Effects of environmental manipulations. J Neurosci 10:436-47
Muller, R U; Kubie, J L; Ranck Jr, J B (1987) Spatial firing patterns of hippocampal complex-spike cells in a fixed environment. J Neurosci 7:1935-50
Fox, S E; Wolfson, S; Ranck Jr, J B (1986) Hippocampal theta rhythm and the firing of neurons in walking and urethane anesthetized rats. Exp Brain Res 62:495-508