Section 7.3.3 Size and duration of representations

See the update to Chapter 3 (section 3.5.5) for more on the estimated numbers of cells firing when an object is represented in the human brain. Note however these studies do not discuss whether there is a threshold (either for consciousness or for being a functioning representation), nor whether the size of the representation varies with stimulus intensity or salience. Levy et al. (2004) mention that attention to a stimulus, which some have taken as an index of consciousness (section 8.3), enhances neuronal firing rates by only 20%.

Side-box 7.2 The anatomy of the thalamus

A massive, two-volume reference work on thalamic anatomy and function has been authored by Jones (2006).

References

Jones, E.G. (2006) The Thalamus, 2nd edition. Cambridge University Press, Cambridge.

Levy, I., Hasson, U. and Malach, R. (2004) One picture is worth at least a million neurons. Current Biology 14, 996-1001.