Distinct "Feeding" and "Hunger Motivating" Systems in the Lateral Hypothalamus of the Rat

Abstract

Electrodes were implanted in the middle hypothalamus of rats to determine the neural organization of the "feeding" centers. Stimulations of the farand midlateral hypothalamic area produced feeding responses in sated animals, but only the former caused sated animals to cross an electrified grill to press a lever for food. After lesions had been made in the medial forebrain bundle, however, stimulations in the far-lateral hypothalamic area resulted in feeding in sated animals but failure to cross the electrical barrier to press a lever for food. Simultaneous far-lateral and "satiety" center stimulations produced feeding in sated animals but failed to "motivate" grill-crossing behavior.

Hypothalamic control of energy balance and the reproductive cycle in the rat

“…The role of this part of the hypothalamus in motivated behaviour has received much attention recently (Miller, Bailey & Stevenson, 1950;Stellar, 1954;Morgane, 1961;Hoebel & Teitelbaum, 1962) and it is probable that the so-called satiety mechanism of the ventromedial nuclei and the closely associated feeding and drinking 'centres' in the lateral hypothalamus are intimately concerned in a variety of drives. All the details of this association are not yet clear, but to regard the ventromedial nucleus simply as a satiety centre reflects merely the preoccupation of individual experimenters.…”

“…Some further subdivision into an anterior part controlling ovulation and a posterior part controlling follicle development may be justified (Gorski & Barraclough, 1962) and the most posterior part we found to be particularly concerned with mating behaviour. Also, this posterior segment overlaps the region governing energy balance, which as Anand & Brobeck (1951) first showed extends laterally towards the medial forebrain bundle and forms part of an extensive 'motivational system' (Morgane, 1961).…”

The limbic brain: Continuing resolution

“…Nauta also noted that there are two descending medial forebrain-midbrain systems, one to the medial midbrain tegmentum and one to the lateral midbrain tegmentum. These appear to represent the continuation of the mid-and far lateral hypothalamus described by Morgane (1961Morgane ( , 1980a. These findings were followed in several, more recent studies providing details of these limbic sub-circuits and networks (Nauta, 1986).…”

Insulin injections and stimulation-bound feeding in the rat

“…1969). Stimulated rats are highly rnotivated to perform instrumental responses which were previously rewarded by food (Morgane, 1961). Since "induced feed ing" also depends on the palatibility of the food (Tenen & Miller, 1964) and satiation (Devor, Wise, Milgram, & Hoebel, 1970), and is decreased by amphetamine and other anorexigenic drugs (Stark & Totty, 1967), one might believe that "induced hunger" is very similar to "natural hunger."…”