We investigated how humans encode large-scale spatial environments using a virtual taxi game. We hypothesized that if 2 connected neighborhoods are explored jointly, people will form a single integrated spatial representation of the town. However, if the neighborhoods are first learned separately and later observed to be connected, people will form separate spatial representations; this should ...

It has been hypothesized that one of the functions of the hippocampus is to enable the learning of relationships between different stimuli experienced in the environment. These relationships might be spatial ("the bathroom is about 5m down the hall from the bedroom") or temporal ("the coffee is ready about 3 min after the button was pressed"). Critically, these spatial and temporal relationship...

A model of place-cell firing is presented that makes quantitative predictions about specific place cells' spatial receptive fields following changes to the rat's environment. A place cell's firing rate is modeled as a function of the rat's location by the thresholded sum of the firing rates of a number of putative cortical inputs. These inputs are tuned to respond whenever an environmental boun...

Given a rectangular m × n matrix stored as a two-dimensional array, we want to transpose it in place andmeasure the cost by the number of memory writes and the number of auxiliary cells used. We propose a transposition algorithm with optimal complexity O(mn) using only min(m, n) auxiliary memory cells. © 2009 Elsevier Inc. All rights reserved.

In this paper, we consider the problem of designing in-place algorithms for computing the maximum area empty rectangle of arbitrary orientation among a set of points in 2D, and the maximum volume empty axisparallel cuboid among a set of points in 3D. If n points are given in an array of size n, the worst case time complexity of our proposed algorithms for both the problems is O(n); both the alg...

An in-place algorithm is one in which the output is given in the same location as the input and only a small amount of additional memory is used by the algorithm. In this paper we describe three in-place algorithms for computing the convex hull of a planar point set. All three algorithms are optimal, some more so than others. . .

We propose a computational model of the CA3 region of the rat hippocampus that is able to reproduce the available experimental data concerning the dependence of directional selectivity of the place cell discharge on the environment and on the spatial task. The main feature of our model is a continuous, unsupervised Hebbian learning dynamics of recurrent connections, which is driven by the neuro...

Tolman proposed that complex animal behavior is mediated by the cognitive map, an integrative learning system that allows animals to reconfigure previous experience in order to compute predictions about the future. The discovery of place cells in the rodent hippocampus immediately suggested a plausible neural mechanism to fulfill the 'map' component of Tolman's theory. Recent work examining hip...

The activity of ensembles of hippocampal place cells represents a hallmark of an animal's spatial experience. The neuronal mechanisms that enable the rapid expression of novel place cell sequences are not entirely understood. Here we report that during sleep or rest, distinct sets of hippocampal temporal sequences in the rat preplay multiple corresponding novel spatial experiences with high spe...