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Moshe Abeles

Gonda Multidisciplinary Brain Research Center
Bar Ilan University
Ramat Gan, Israel

Space and Time of Cortical Activity

To understand how the cortex works, we need to define accurate scales in space and time. Anatomical and microscopic studies have parceled the cortex into different scales such as cytoarchitectonic areas, hyper-columns, mini-columns, single neurons, individual synapses, single channels, etc.. Because neighbouring neurons can have very different properties, individual neurons appear to be the largest unit that can be used to understand cortical information processing mechanisms.

Activity can 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. A single neuron can be part of different processes at different times. It remains unclear how fast a neuron can switch its functional properties. If such switching can be made on a ms time scale, fast and efficient computations can be made. We show that the temporal precision of cortical neurons can be better than 1 ms.