STUART, D. G. 
posterior hypothalamus augmented shivering. Similar results were 
obtained by stimulating contralateral loci. 
The ratio of septal locus stimulus intensity for the suppression 
of shivering to anterior hypothalamic intensity was 5.0 in Cat No. 
ST 33 and 2.0 in Cat No. ST 34. A similar intensity ratio for 
ventrolateral posterior hypothalamus to anterior hypothalamus was 
1.7 in Cat No. ST 36, 1.0 in Cat No. ST 37 for right side stimulation 
and 1.5 for left side stimulation. In all experiments in which shiv- 
ering was suppressed by ventrolateral posterior hypothalamic 
stimulation, it could be evoked by dorsomedial posterior hypothal- 
amic stimulation. 
As with the production of shivering, bilateral suppression of 
shivering was evoked by ipsilateral stimulation. Variability existed 
as to the extent to which right and left fore and hindlimb shivering 
was suppressed either strongly or mildly. No consistent pattern 
emerged from these experiments. Similarly, some variability 
existed as to the extent of forelimb vs. hindlimb shivering suppres- 
sion, but no consistent pattern was evident. 
In the above expdriments the inhibition of shivering was general- 
ly accompanied by a slowing of respiration and heart rate. Alter- 
ations in fronto-occipital EEG wave patterns were not obvious 
during such stimulation, but none of these parameters was system- 
atically studied in the course of these investigations. 
Comments. It was previously shown that a higjier intensity of 
stimulation is needed to evoke shivering during septal stimulation 
than during posterior hypothalamic stimulation. The results on 
shivering suppression are similar, a higher intensity of stimulus 
being used to suppress shivering during septal stimulation than 
during anteriorhypothalam ic stimulation. Such results are additional 
physiogical confirmation of the known anatomy of caudal septal 
projections. 
The experiments on Cats No. ST 27, 29, and 31, with fornices 
cut and efferent projections denervated, would suggest that the 
shivering suppression produced by medial septal stimulation was 
not due to stimulating fornical fibers passing througji the septum 
to either the hypothalamus or midbrain. However, it is known from 
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