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     Ever since Thursday’s lecture I’ve been thinking about the example of the poor decapitated frog twitching his hind leg after being tickled; the capabilities of the spinal cord alone continues to amaze me. I understand how this mechanism works using the concept of topographic organization of the spinal cord, but it appears that all of these output movements (of the examples we were given) are reflex and defensive responses. They are actions that would commonly be called involuntary. In the example of quadriplegia, Christopher Reeves withdrew his foot when touched, but was not able to reproduce the motion when asked. So in an isolated spinal cord it would seem that in order to get a fixed response the right sensory stimulus must be applied.         

         The mechanisms of the spinal cord and corresponding extremities are enough to sustain life (with a supply of nutrients and oxygen) however; they seem to be lacking the experience aspect of living. In the above example of the frog, one could consider the reflex as being an experience, but it is limited in the sense that if you tickle the frog in the same way it will most likely produce the same twitching behavior. It would seem logical to me to assume that if the same stimulus was applied under the same conditions to produce an identical behavior then the same neural pathway must have been used. This descriptions seems comparable to a machine, and machines are not usually thought of as experiencing. If the spinal cord alone is not capable of experiencing (in the sense of perceiving and relating) then it must be the brain working in concurrence with the spinal cord to create this sensation of experience.

         When the body encounters some external stimulus it will elicit a response in the nervous system; if your hand is stocked sensory neurons send the ‘signal’ to the upper part of your spinal cord, which then returns a signal to the motor neurons in your arm, most likely causing you to retract it. I would like to propose that after the signal goes to the spinal cord, a signal is not only sent to the motor neurons, but also to the brain. It is in the brain where the electrochemical information is ‘interpreted’ so that you are able to make a connection between the shock and the pain in your hand, and possibly produce a behavior in addition to the reflex (verbally expressing that pain for example).

         It is still unclear to me what the actually process of experiencing is; this is merely an interpretation of information. I am also unclear on how information is stored in the form of memory. In general people learn from experience, but in what form is this experience stored? And are there other forms of learning behaviors? Babies seem to be able to learn behaviors through imitation, is there specific neurons responsible for this type of learning as opposed to experiential learning? So many questions so little time.