URGENT: NutraSweet/MENTHANOL/TRUTH

[Mark R. Opp, Ph.D.]

The hypothesis that sleep serves to concern engery is an old one, dating 
back to the late 60s early 70s.  The question of sleep function, whether 
energetic, or for cooling the brain, or for memory consolidation,etc is 
complicated by the fact that sleep is evolutionary an old behavior that 
may have evolved at least twice.  The benefits of sleep differ from one 
species to the next, and differ within species depending on current 
ecological conditions, etc.  This makes the development of unitary 
hypotheses for sleep function very difficult, to say the least.  One of 
the newer theories for sleep function is couched within the context of 
the neuronal group selection hypothesis.  This hypothesis 
(based largely on work of Edelman) emphasizes that neuronal groups 
compete for neurons via use-dependent synaptic formation and atrophy.  
Sleep serves to stabilize these competitive processes by providing a 
pattern of stimulation that serves to maintain a synaptic infrastructure 
upon which wakefulness-driven sunaptic changes are superimposed.  As 
such, sleep is "quantal" in that it is a statistical property of a 
population of neuronal groups in different states.  This theory is 
proposed by Krueger and Obal, and the initial formulation appears in the 
Journal of Sleep Research 2:63-69, 1993.