Space and Time of Cortical Activity
- Moshe Abeles (Bar Ilan University, Ramat-Gan, Israel)
Abstract
We wish to evaluate what are the scales in space and time needed for understanding how the cortex works.
Anatomical and microscopical studies have parceled the cortex on different scales: Cytoarchitectonic Areas, Hyper-Columns, Mini-Column, Single Neuron, Individual Synapses, a Single Channel. I shall provide evidence that surface maps are much too coarse. The individual neurons seem to be the largest unit that can be used to understand the cortical mechanisms for processing information.
Activity may be measured by fMRI (or PET) on a time scale of seconds, by EEG (or MEG) on a Time scale of a small fraction of a second and by microelectrodes on a time scale of milliseconds or less. I shall provide experimental evidence that the firing time of cortical neurons may fire at a precision better then 1 ms.
Some theoretical implications of these findings will be discussed.
Supported in part by Grants from ISF, DIP, and the Rich Center.