STUART, D. G. 
(Chatonnet, 1961; Hammel et al., 1960;Kundtetal., 1957), shivering 
has been evoked by thermal stimulation, but this technique does not 
permit a precise localization of the effective region. Others have 
demonstrated the production of shivering during application of an 
electrical stimulus to the forebrain's septum in anesthetized cats 
(Akert and Kesselring, 1951) and unanesthetized goats (Andersson, 
1957) and to the midbrain and pons in anesthetized cats (Birzis and 
Hemingway, 1957). In the studies using cats, production of shivering 
by stimulation of the hypothalamus was mentioned. In each case 
only one hypothalamic locus was stimulated. In all three reports 
the investigators' efforts were devoted mainly to regions more 
rostral or more caudal than the hypothalamus. Since decorticate 
preparations with the septum destroyed can shiver (Aring, 1935; 
Bard, 1961; Dusser de Barenne, 1920; Pinkston et al., 1934), it 
would seem that the most rostral prosencephalic region whose 
stimulation consistently produces shivering is one whose ablation 
does not affect shivering. Anatomically the septal region of the 
forebrain, which is but a vestige in man (septum pellucidum), has 
been shown to have intimate connections with neocortical and 
rhinencephalic pathways to and from the thalamus, hypothalamus 
and midbrain (Fox, 1920; Pribram and Kruger, 1954). Thus, it 
mig^t well be, but is not proved, that the septum is involved in 
alterations in temperature regulation evoked by classical Pavlovian 
conditioning (Bykow, 1957), the production of shivering by hypnotic 
suggestion (Gessler and Hansen, 1927) and "psychological aspects" 
to cold tolerance mentioned in recent reports of human adaptation 
to cold stress (Adams and Covina, 1958; Scholander et al., 1958; 
and Wyndham and Morrison, 1958). 
However, if the septum is involved in the production of shiv- 
ering, its activity should be but secondary to hypothalamic activity 
in that it can be ablated without affecting shivering, and all known 
caudally projecting septal effe rents synapse in the hypothalamus 
to make direct connections with the midbrain (Nauta, 1958; Sprague, 
1950). Neither these fibers nor those septal projections to the 
thalamus could produce shivering, since the thalamus and also the 
hippocampus, from which the fornical fibers arise, can be ablated 
without affecting the production of shivering. 
Anterior hypothalamic stimulation either thermally (Eliasson 
and Strom, 1950; Freeman and Davis, 19 59; Hemingway et al., 1940; 
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