The renin-angiotensin system and thirst: a reevaluation. II. Drinking elicited in rats by caval ligation or isoproterenol

Ligation of the inferior vena cava and administration of isoproterenol have been shown to stimulate renin secretion and to augment water intake in rats. However, the present experiments suggested that the plasma renin activities produced by these treatments do not account for more than 20% of the observed drinking behavior. Direct measurements of arterial blood pressure further indicated that nephrectomized rats go into hypotensive shock after caval ligation or isoproterenol treatment. Drinking was elicited in these hypotensive animals by systemic injection of hypertonic NaCl solution, renin, or Pitressin, or by intracranial injection of angiotensin, but in each case a rapid increase in blood pressure also was observed. Thus, it appears that nephrectomy reduces water intake in these animals by undermining their general capacity to behave rather than by removing a specific dipsogenic stimulus. These and other results suggested that drinking elicited in rats by caval ligation or isoproterenol is not mediated by the renin-angiotensin system.     

Measuring Social Status with Occupational Information: A Simple Method1

A measure of social status was devised: a multiple-choice question that obtains occupational information and is scalable with both the Duncan Socioeconomic Index and the Siegel Prestige Scale. The correlations of this device with other measures of social status and with tests of general ability were assessed in a study of white and black Navy recruits. The correlations were similar to those obtained with a conventional measure that relies on judges scaling occupational information elicited by an openended question. The present device may be a good prototype for a standardized, multiple-choice measure of social status.     

Water and NaCl intake after furosemide treatment in sheep (Ovis aires)

Intravenous infusion of the natriuretic drug furosemide in sheep led to the excretion of large quantitites of hypotonic urine. The sheep consumed more water than was needed simply to restore osmotic equilibrium. The stimulus for the additional intake was presumably hypovolemia resulting from the loss of sodium in urine. Despite the natriuresis, in only 2 of 15 experiments did sheep drink significant amounts of .5 M NaCl solution during the first 10 hr after the onset of furosemide treatment, and hemoconcentration and arterial hypotension were evident during this time. By 24 hr, however, the saline consumption in all but three experiments had increased and compensated adequately (together with the water intakes) for the furosemide-induced loss of sodium-rich fluid in urine. These results provide evidence that following acute hypovolemia in sheep, as in rats, the onset of sodium appetite is delayed relative to the appearance of thirst.     

Test Difficulty and Stereotype Threat on the GRE General Test1

This study investigated (a) the ability to minimize or eliminate stereotype threat by reducing the difficulty of items administered via a computer‐adaptive version of the Graduate Record Examinations General Test; and (b) the generalizability of these findings for Black students as well as women, and for verbal as well as quantitative sections of the test. Standard and easier versions of the test, and measures of stereotype threat and possible symptoms or sequelae of stereotype threat were administered to students bound for graduate school or already there. Reducing test difficulty did not have any differential effects on test performance or on explicit indexes of stereotype threat for White and Black students, and for men and women, that were statistically and practically significant. However, such effects did occur for some symptoms or sequelae, mainly for White students and women.     

Portrayals of Intimate Partner Violence in Music Videos: Effects on Perceptions of IPV Warning Signs

The present research examined the effects of viewing music videos containing intimate partner violence (IPV) on minimization of warning signs of IPV, that is, perceiving that psychologically controlling and demeaning behaviors are not abusive. One video portrayed overt IPV in a narrative form and the other contained overt IPV but no identifiable narrative. Lyrics for both included violent content, but the music was distinctly different—one song was rap interspersed with somber singing and the other had an upbeat pop sound. The video and audio channels were combined in a 2-×-2 factorial design with an external control group so that all combinations of narrative and non-narrative video with the rap and pop music were presented to college student participants (153 participants, 53% female) in a between-subjects design. Participants showed greater minimization, that is, they were less likely to perceive the psychologically controlling and demeaning behaviors as abusive to the extent that they were transported into the video and enjoyed it. Minimizing perceptions of abuse as a function of viewing music videos that portray IPV is discussed as a negative consequence of such videos.     

Changing Gender Norms for Alcohol Consumption: Social Drinking and Lowered Inhibitions at Bachelorette Parties

In this research, we examined the role of alcohol as both substance and symbol at bachelorette parties. The bachelorette party is characterized by ritualized embarrassment of the bride and by sexualized games, both of which are made easier by heavy alcohol consumption. As there are few occasions when it is considered socially acceptable for women to drink, the bachelorette party provides a unique opportunity to explore womens social drinking and public drunkenness. Based on interviews with 51 women we found that drinking seemed to add to the fun of bachelorette parties and that group alcohol consumption appeared to increase social solidarity as women at bachelorette parties bonded over their shared experience. Finally, women relied on alcohol to lower inhibitions so that they were able to feel justified in engaging in deviant behavior. Womens use of alcohol in this ritual challenges existing gender norms and conceptions of masculinity and femininity.     

RESPONDING MAINTAINED BY INTERMITTENT REINFORCEMENT: IMPLICATIONS FOR THE USE OF EXTINCTION WITH PROBLEM BEHAVIOR IN CLINICAL SETTINGS

Results of basic research have demonstrated that behavior maintained on an intermittent schedule of reinforcement (INT) will be extinguished more slowly than behavior maintained on a continuous schedule (CRF). Although these findings suggest that problem behaviors may be difficult to treat with extinction if they have been maintained on INT rather than on CRF schedules, few applied studies have examined this phenomenon with human behavior in clinical settings. The purpose of this study was to determine whether problem behavior maintained on CRF schedules would be extinguished more rapidly than behavior maintained on INT schedules. Three individuals diagnosed with profound mental retardation participated after results of pretreatment functional analyses had identified the sources of reinforcement that were maintaining their self-injury, aggression, or disruption. Subjects were exposed to extinction following baseline conditions with CRF or INT schedules alternated within reversal or multielement designs. Results suggested that problem behaviors may not be more difficult to treat with extinction if they have been maintained on INT rather than CRF schedules. However, switching from an INT to a CRF schedule prior to extinction may lower the baseline response rate as well as the total number of responses exhibited during extinction.     

EFFECTS OF SUBJECT- VERSUS EXPERIMENTER-SELECTED REINFORCERS ON THE BEHAVIOR OF INDIVIDUALS WITH PROFOUND DEVELOPMENTAL DISABILITIES

Results from a number of studies have shown that individuals with profound developmental disabilities often show differential approach behavior to stimuli presented in a variety of formats, and that such behavior is a reasonably good predictor of reinforcement effects when these “preferred” stimuli are used subsequently in a contingent arrangement. Recent data suggest that reinforcement effects may be enhanced further by allowing individuals to select, just prior to training sessions, which (of several) preferred stimuli would be used as reinforcers, but whether this method is superior to one based on selection by a teacher or therapist has not been adequately addressed. We compared the effects of these two methods of reinforcer selection on rates of responding on a free-operant task, using stimuli previously identified as potential reinforcers. Results obtained with 4 subjects indicated little or no difference in reinforcement effects when stimuli were selected by subjects rather than experimenters. Implications of these results with respect to choice and its relation to reinforcement are discussed.