The Workings of the Brain: Development, Memory, and Perception
Rodolfo R. Llinas (ed), 1990

Excellent Early Scientific American Reprints
This book includes 10 papers on the brain originally published as articles in Scientific American from 1976 through 1987. Unlike much later SA material (in my opinion), the papers here have depth, detail, and make the reader feel more like a participating scientist than like an uninformed bystander off the street.

Traces of a Midbrain Visual System
Recent evidence from blindsight patients (
Damasio , Dennett , , ) suggests that some of the old midbrain visual system may still be working. In cases where lesions exist in certain parts of the visual cortex, but the eyes are intact as are the midbrain and thalamic systems, through which the optic nerve passes on the way to the cortex, the patient can frequently report correctly on stimuli presented in the "blind" area, even though the person reports seeing nothing. One explanation for this condition holds that the midbrain or thalamic visual systems are reporting their findings, independent of any cortical activity.

Retinal Firing Patterns
The final attachment of optic nerve axons to their destination areas in the tectum are said to depend upon firing patterns which result from illumination of neighboring areas of the retina. This hypothesis forces the conclusion that the eye is not capable of clear vision at the time of birth. My question is whether the vision would be good enough to explain the ability of many large quadripeds, especially the ungulates, to get up and run around (and avoid predators) within a few moments after birth. As soon as the leg muscles are steady enough, the calf stands and then starts to run around mom. Perhaps it only needs to be able to see well enough to find mom, but I think this issue needs to be explored.

Of course, it's also true that this paper was published in 1982. The situation is probably well understood by now (in 2001).


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