The concept that the nervous system, ie the brain and spinal cord, is an input- output box that can be divided and subdivided into smaller and smaller input- output units, of which the neuron is the smallest autonomous input-output element, increases my comfort, by a small degree, with the idea that the brain is behavior. The fact that there are so many neurons, and even a greater number of possible connections and pathways between these neurons, makes it a bit easier to account for the many many different types of behaviors that have been observed. On the other hand, the concept of the neuron being the smallest input-output box also makes the idea that the brain is behavior, harder to swallow. If you take a look at how neurons work, the mechanism is very cellular. A neuron is activated if it is depolarized beyond its threshold. If this is the case then an action potential, that travels from one end of the neuron to the other, is propogated within the neuron. The action potential is propogated from one neuron to another, through the opening and closing of ion channels on the post-synaptic cell, which is in turn a result of the binding of neurotransmitters from the pre-synaptic cell to receptors on the postsynap- tic cell. When you examine this whole process, it is difficult to see how such a fundamental process can account for complex behaviors such as, say mating songs and dances.

Fair enough. Indeed, better than that. Question for us, at this point, is precisely to understand those "cellular" events, and see if, by combining a number of cells, we can get something that looks like behavior. New properties, from cellular underpinnings? We'll see. PG