Functional differentiation within hypothalamic behavioral systems in the cat

Abstract

A stimulation analysis was completed, by the use of roving stimulation electrodes, -of an area in the cat hypothalamus where biting attack and threat behavior can be elicited. Results indicated that, while attack and threat have partially overlapping anatomical representations, there is considerable anatomical dissociation between these behaviors, even within overlap areas. Further, we found that a composite stimulation map, based on anatomical data pooled across animals, substantially overestimated the size of response areas and the degree of anatomical overlap between responses for a given animal. The results support the view that the hypothalamus contains partly overlapping, but functionally specific, mechanisms for different behaviors.

A comparison of hypothalamically induced biting attack with natural predatory behavior in the cat.

“…The electrode loci that were formally tested are designated by cat number, which relates these loci to behaviors detailed in Table 1. Consistent with previous reports, attack points were located primarily in the lateral hypothalamus (Berntson & Beattie, 1975;Roberts & Kiess, 1964;Wasman & Flynn, 1962).…”

“…Again, these responses were not invariable accompaniments of attack, and in two of the strongest and most complete cases of elicited attack no escape or threat responses were seen. Indeed, threat, attack, and escape appear to be distinct behavior patterns mediated by separate neural systems (Bergquist, 1970;Berntson, 1972;Berntson & Beattie, 1975;Chi & Flynn, 1971;Hunsperger, 1956;Wasman & Flynn, 1962), suggesting that cases of attack accompanied by threat or escape may have resulted from current spread between response systems.…”

Brain imaging and cognitive neuroscience: Toward strong inference in attributing function to structure.

“…Similarly, the existence of functionally distinct but overlapping circuits could lead to an underestimate of the degree of functional localization, as the overlapping area would be activated during multiple cognitive or behavioral contexts. The latter appears to account at least in part for the historical controversy, discussed above, over the motivational specificity of hypothalamic and limbic circuits (Berntson & Beattie, 1975; Roberts, 1969).…”

Motivated behaviors elicited from hypothalamus, midbrain, and pons of the guinea pig (Cavia porcellus).

“…Thus, one quarter to one half of the negative points probably resulted from true individual differences, most likely in the anatomical repre-sentation of eating in the hypothalamus. Since appreciable individual differences have been reported in cortical localization (Asanuma & Sakata, 1967;Merzenich, Knight, & Roth, 1975) and hypothalamic localization (Berntson & Beattie, 1975), variations in the precise location of subcortical response zones in different guinea pigs would not be surprising and could account for the existence of such negative sites. Composite diagrams based on data pooled from animals manifesting such variations would be expected to overestimate the size of response zones in individual guinea pigs and to exaggerate the degree of overlap of zones for different responses.…”