Lack of tolerance to contrast-reducing actions of chlordiazepoxide with repeated reward reductions

Anxiolytic-like effect of ejaculation upon frustration

“…Moreover, the absence of stress during the first episode of reward downshift is consistent with data showing that the plasma levels of the stress hormone corticosterone remain unaltered (Flaherty, Becker, & Pohorecky, 1985;Flaherty, Greenwood, Martin, & Leszczuk, 1998) and that chlordiazepoxide, diazepam, midazolam, flurazepam, and ethanol are ineffective in reducing behavioral contrast in a first postshift session (Becker, 1986;Becker & Flaherty, 1982;Flaherty, Grigson, & Lind, 1990;Flaherty, Clarke, & Coppotelli, 1996). On the other hand, elevated corticosterone levels after a second postshift day (Mitchell & Flaherty, 1998) and a partially reversed suppression of consummatory behavior by antianxiety agents have been found in the second negative contrast session (Becker & Flaherty, 1982;Flaherty et al, 1996). Collectively, these studies suggest that involvement of emotional processes during the first incident of a surprising reward downshift is scarce (if not absent).…”

“…The idea of a search for the missing solution has been supported by experiments in which an increase of exploratory behavior (i.e., nose-down locomotion, noseup posture, and open rearing) has been measured when an animal has suffered an incentive downshift from 32% to 4% sucrose solutions in a radial maze (Pecoraro, Timberlake, & Tinsley, 1999) and, less directly, by experiments in which it has been found that there is increased locomotion after a 32%-to-4% shift (Flaherty, Blitzer, & Collier, 1978;Pellegrini & Mustaca, 2000). Moreover, the absence of stress during the first episode of reward downshift is consistent with data showing that the plasma levels of the stress hormone corticosterone remain unaltered (Flaherty, Becker, & Pohorecky, 1985;Flaherty, Greenwood, Martin, & Leszczuk, 1998) and that chlordiazepoxide, diazepam, midazolam, flurazepam, and ethanol are ineffective in reducing behavioral contrast in a first postshift session (Becker, 1986;Becker & Flaherty, 1982;Flaherty, Grigson, & Lind, 1990;Flaherty, Clarke, & Coppotelli, 1996). On the other hand, elevated corticosterone levels after a second postshift day (Mitchell & Flaherty, 1998) and a partially reversed suppression of consummatory behavior by antianxiety agents have been found in the second negative contrast session (Becker & Flaherty, 1982;Flaherty et al, 1996).…”

“…Flaherty et al (1985;Flaherty et al, 1998) found increased corticosterone levels after the second postshift trial of a cSNC procedure, but not after the animals first detected the shift. They also observed that anxiolytic agents (e.g., chlordiazepoxide) reduced the behavioral contrast effect on the second trial after the reinforcement downshift, but not on the first contrast trial (Becker & Flaherty, 1982;Flaherty, Grigson, & Lind, 1990;Flaherty et al, 1996). On that basis, different authors have elaborated theories about frustration phenomena in which two distinct behavioral/physiological sequential processes taking place in the animals that face a reward downshift are considered (Amsel, 1992;Flaherty, 1996).…”

“…It has been reported that anxiolytic agents facilitate recovery from consummatory contrast, as measured during the second postshift trial (Becker & Flaherty, 1982;Flaherty et al, 1996). Besides, Flaherty, Grigson, and Rowan (1986) and have shown that the administration of chlordiazepoxide and midazolam, respectively, prior to to the second postshift session in a cSNC, has an acute consummatory recovery effect only during that session, given that the animals presented a behavioral contrast again in the third and fourth postshift sessions.…”

“…More specifically, if an anxiolytic-like effect of ejaculation (Fernández-Guasti et al, 1989; Rodríguez-Manzo et al, 1999) is expected, ejaculators will be predicted to behave like those subjects treated with anxiolytic drugs in cSNC situations in previous studies (Becker & Flaherty, 1982;Flaherty, Grigson, & Lind, 1990;Flaherty et al, 1996). Therefore, we expected to find that ejaculations before the second postshift trial would increase the consummatory recovery and decrease the subjects' ambulation and rearing behavior in a 32%-to-4% downshift situation.…”