Beyond the Cognitive Map: From Place Cells to Episodic Memory
MIT Press, 1999 - Medical - 420 pages
There are currently two major theories about the role of the hippocampus, a distinctive structure in the back of the temporal lobe. One says that it stores a cognitive map, the other that it is a key locus for the temporary storage of episodic memories. A. David Redish takes the approach that understanding the role of the hippocampus in space will make it possible to address its role in less easily quantifiable areas such as memory. Basing his investigation on the study of rodent navigation--one of the primary domains for understanding information processing in the brain--he places the hippocampus in its anatomical context as part of a greater functional system.
Redish draws on the extensive experimental and theoretical work of the last 100 years to paint a coherent picture of rodent navigation. His presentation encompasses multiple levels of analysis, from single-unit recording results to behavioral tasks to computational modeling. From this foundation, he proposes a novel understanding of the role of the hippocampus in rodents that can shed light on the role of the hippocampus in primates, explaining data from primate studies and human neurology. The book will be of interest not only to neuroscientists and psychologists, but also to researchers in computer science, robotics, artificial intelligence, and artificial life.
Results 1-5 of 5
Muller and Kubie (1987) found that when a barrier was added to a cylinder, the
firing rates of 9 out of 10 cells whose fields intersected the barrier diminished.
The remaining cell increased its firing rate. Substituting a transparent barrier did
Cells with firing rates reflecting head direction have been discovered in a number
of structures in the rodent brain: post- subiculum (NS; Ranck, 1984; Taube, Muller
, and Ranck, 1990a, 1990b), the anterior thalamic nuclei (ATN; Blair and Sharp ...
Another way to view the coherency of a population is to plot the sum of the place
fields of each cell, weighted by their current firing rates. A coherent
representation of position will show up clearly as a single pocket of activity. The
Neither of these studies measured spatial parameters of the neurons, measuring,
instead cell firing correlations to pictures and syllables (Halgren, Babb, and
Crandall, 1978) or to faces (Fried, MacDonald, and Wilson, 1997). Typical firing
Both of these techniques measure blood flow changes not neuronal firing rates.
Most researchers believe that increased blood flow signifies increased neuronal
firing (Fox and Raichle, 1986; Ogawa et alv 1992), but debate about its meaning