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Selected AbstractsThe microstructure of ethanol drinking: genetic and behavioral factors in the control of drinking patternsADDICTION, Issue 8s2 2000Herman H. Samson The concept of craving can be examined in many different ways, depending upon the individual definition of the term. Using the concepts and procedures of regulatory behavior analysis, this review explores behavioral studies in rats that have some relationships to some of the possible processes that underlie the concept of craving in humans. Data are reviewed from studies employing both limited and continuous access to ethanol, examining the role of access availability, ethanol initiation, response cost, time since last access, composition of the ethanol containing solution and genetic selection. From this review, it is clear that rat models can implicate important variables involved in the control of human alcohol consumption. [source] Motivation for Alcohol Becomes Resistant to Quinine Adulteration After 3 to 4 Months of Intermittent Alcohol Self-AdministrationALCOHOLISM, Issue 9 2010Frederic W. Hopf Background:, Continued consumption of alcohol despite deleterious consequences is a hallmark of alcoholism and represents a critical challenge to therapeutic intervention. Previous rat studies showed that enduring alcohol self-administration despite pairing alcohol with normally aversive stimuli was only observed after very long-term intake (>8 months). Aversion-resistant alcohol intake has been previously interpreted to indicate pathological or compulsive motivation to consume alcohol. However, given the time required to model compulsive alcohol seeking in previous studies, there is considerable interest in developing more efficient and quantitative rodent models of aversion-resistant alcohol self-administration. Methods:, Outbred Wistar rats underwent 3 to 4 months or approximately 1.5 months of intermittent, home-cage, two-bottle access (IAA) to 20% alcohol (v/v) or water. Then, after brief operant training, the effect of the bitter-tasting quinine (0.1 g/l) on the motivation to seek alcohol was quantified via progressive ratio (PR). Motivation for quinine-adulterated 2% sucrose under PR was assayed in a separate cohort of 3 to 4 months IAA rats. The effects of quinine on home-cage alcohol consumption in IAA rats and rats with continuous access to alcohol were also examined. Finally, a dose,response for quinine taste preference in IAA and continuous-access animals was determined. Results:, Motivation for alcohol after 3 to 4 months IAA, measured using an operant PR procedure, was not altered by adulteration of alcohol with 0.1 g/l quinine. In contrast, after 3 to 4 months of IAA, motivation for sucrose under PR was significantly reduced by adulteration of sucrose with 0.1 g/l quinine. In addition, motivation for alcohol after only approximately 1.5 months IAA was significantly reduced by adulteration of alcohol with 0.1 g/l quinine. Furthermore, home-cage alcohol intake by IAA rats was insensitive to quinine at concentrations (0.01, 0.03 g/l) that significantly reduced alcohol drinking in animals with continuous access to alcohol. Finally, no changes in quinine taste preference after 3 to 4 months IAA or continuous access to alcohol were observed. Conclusions:, We have developed a novel and technically simple hybrid operant/IAA model in which quinine-resistant motivation for alcohol is evident after an experimentally tractable period of time (3 to 4 months vs. 8 months). Quinine dramatically reduced sucrose and water intake by IAA rats, indicating that continued responding for alcohol in IAA rats despite adulteration with the normally aversive quinine might reflect maladaptive or compulsive motivation for alcohol. This model could facilitate identification of novel therapeutic interventions for pathological alcohol seeking in humans. [source] Early Social Isolation in Male Long-Evans Rats Alters Both Appetitive and Consummatory Behaviors Expressed During Operant Ethanol Self-AdministrationALCOHOLISM, Issue 2 2009Brian A. McCool Background:, Postweaning social isolation in rats produces profound and long-lasting cognitive and behavioral deficits in adult animals. Importantly, this housing manipulation alters sensitivity to a number of drugs of abuse including ethanol. However, most studies with ethanol have utilized continuous or limited home-cage access to examine interactions between juvenile social experience and drinking. More recently, social isolation was shown to increased ethanol responding in a "dipper" model of self-administration (Deehan et al., 2007). In the current study, we utilize a "sipper" operant self-administration model to distinguish the effects of isolation rearing on ethanol seeking- and drinking-related behaviors. Methods:, Postweaning juvenile male Long-Evans rats were placed into 2 housing groups for 6 weeks: one group consisted of individually housed animals; the second group was housed 4 animals per cage. Following the isolation period, anxiety-like behavior was assessed to confirm the efficacy of the isolation procedure. In some animals, ethanol drinking in the home cage was assessed using a continuous access, 2-bottle choice paradigm. All animals were then individually housed and trained to lever-press for a sipper tube containing either an ethanol solution or a sucrose solution. Results:, Postweaning social isolation increased the expression of anxiety-like behavior in the elevated plus maze but not the light-dark box. Ethanol consumption was also increased during continuous home-cage access with the 2-bottle choice paradigm. During operant self-administration, isolation housing increased the response rate and increased ethanol consumption but did not alter responding for or consumption of sucrose. The housing manipulation did not change the total number of lever responses during extinction sessions. Paired-pulse inhibition deficits that are characteristic of juvenile isolation remained intact after prolonged experience with sucrose self-administration. Discussion:, The effects of postweaning social isolation on ethanol drinking in the home cage are also manifest during operant self-administration. Importantly, these alterations in adult operant self-administration are ethanol-specific. [source] Time Course of Elevated Ethanol Intake in Adolescent Relative to Adult Rats Under Continuous, Voluntary-Access ConditionsALCOHOLISM, Issue 7 2007Courtney S. Vetter Background: Adolescence is a period of elevated alcohol consumption in humans as well as in animal models. Previous studies in our laboratory have shown that adolescent Sprague,Dawley rats consume approximately 2 times more ethanol on a gram per kilogram basis than adult animals in a 2-bottle choice free-access situation. The purpose of the present study was to examine the time course and pattern of elevated ethanol intake during adolescence and the adolescent-to-adult transition, contrast this intake with ontogenetic patterns of food and water intake, and determine whether adolescent access to ethanol elevates voluntary consumption of ethanol in adulthood. Methods: Adolescent [postnatal day (P)27,28] and adult (P69,70) male Sprague,Dawley rats were singly housed with continuous access to both water and 1 of 3 experimental solutions in ball-bearing,containing sipper tubes: unsweetened ethanol (10% v/v), sweetened ethanol (10% v/v+0.1% w/v saccharin), and saccharin alone (0.1% w/v). Results: Ethanol consumption plateaued at approximately 7.5 g/kg/d during the first 2 weeks of measurement (i.e., P28,39) in early adolescence, before declining sharply at approximately P40 to levels that were only modestly elevated compared with adult-typical consumption patterns that were reached by approximately P70. In contrast, intake of food and total calories showed a more gradual decline into adulthood with no distinguishable plateaus in early adolescence. When adolescent-initiated and adult-initiated animals were tested at the same chronological age in adulthood, animals drank similar amounts regardless of the age at which they were first given voluntary access to ethanol. Conclusions: Taken together, these data suggest that the elevated ethanol intake characteristic of early-to-mid adolescence is not simply a function of adolescent-typical hyperphagia or hyperdipsia, but instead may reflect age-related differences in neural substrates contributing to the rewarding or aversive effects of ethanol, as well as possible modulatory influences of ontogenetic differences in sensitivity to novelty or in ethanol pharmacokinetics. Voluntary home cage consumption of ethanol during adolescence, however, was not found to subsequently elevate ethanol drinking in adulthood. [source] Helplessness in the Tail Suspension Test Is Associated with an Increase in Ethanol Intake and Its Rewarding Effect in Female MiceALCOHOLISM, Issue 3 2005Yann Pelloux Background: Depression is frequently observed in drug abusers. However, depression may be a primary factor of predisposition to drug abuse or a consequence of drug abuse. The aim of this study was to analyze the influence of a preexisting depressive-like state/helplessness on subsequent alcohol responsiveness in mice. Methods: Male and female CD1 mice were selected according to their immobility time in the tail suspension test, and only mice with "high immobility" and "low immobility" time were retained. Using a two-bottle free-choice paradigm, these mice were given continuous access to tap water or solutions of ethanol (3,20% v/v), quinine (12.5,50 mg/liter), or sucrose (1,4% w/v). In female mice, rewarding and aversive effects of ethanol (1.5 and 3 g/kg, intraperitoneally) were also investigated using the conditioned place preference and the conditioned taste aversion paradigms. Results: Female mice were more immobile and drank more ethanol than male mice. No striking sex difference was observed in quinine consumption. Sucrose intake was higher in female than in male mice, whatever the solution concentration. At the 4% concentrated solution, a sucrose-induced increase in daily fluid intake was observed only in female mice. Female mice with high immobility time (HI) consumed more ethanol at the highest concentration than female mice with low immobility time (LI), whereas no difference was observed between HI and LI male mice. Moreover, whereas LI female mice failed to express place conditioning induced by the 3-g/kg dose of ethanol, HI female mice were strongly responsive to the rewarding effect of this high ethanol dose. Ethanol dose-dependently induced a conditioned taste aversion with a similar magnitude in both LI and HI female mice. Conclusions: The findings indicate that female CD1 mice tend to drink greater amounts of ethanol or sucrose solutions than male CD1 mice, suggesting that female mice may be a better model of excessive alcohol intake. Furthermore, no relationship was found between immobility scores and ethanol consumption in male mice. On the contrary, within female mice, HI mice consumed higher amounts of ethanol than LI mice probably because they experienced greater rewarding effects of ethanol. The present results support the hypothesis that depressive-like responses may predispose to ethanol abuse in female mice. [source] Effects of Long-Term Episodic Access to Ethanol on the Expression of an Alcohol Deprivation Effect in Low Alcohol,Consuming RatsALCOHOLISM, Issue 12 2004Richard L. Bell Background: The alcohol-preferring (P) and -nonpreferring (NP) and high alcohol,drinking (HAD) and low alcohol,drinking (LAD) rats have been selectively bred for divergent preference for ethanol over water. In addition, both P and HAD rats display an alcohol deprivation effect (ADE). This study was undertaken to test whether the NP, LAD-1, and LAD-2 lines of rats could display an ADE as well. Method: Adult female NP, LAD-1, and LAD-2 rats were given concurrent access to multiple concentrations of ethanol [5, 10, 15% (v/v)] and water in an ADE paradigm involving an initial 6 weeks of 24-hr access to ethanol, followed by four cycles of 2 weeks of deprivation from and 2 weeks of re-exposure to ethanol (5, 10, and 15%). A control group had continuous access to the ethanol concentrations (5, 10, and 15%) and water through the end of the fourth re-exposure period. Results: For NP rats, a preference for the highest ethanol concentration (15%) was evident by the end of the fifth week of access (,60% of total ethanol fluid intake). Contrarily, LAD rats did not display a marked preference for any one concentration of ethanol. All three lines displayed an ADE after repeated cycles of re-exposure to ethanol, with the general ranking of intake being LAD-1 > NP > LAD-2 (e.g., for the first day of reinstatement of the third re-exposure cycle, intakes were 6.5, 2.9, and 2.4 g/kg/day compared with baseline values of 3.1, 2.0, and 1.3 g/kg/day for each line, respectively). By the 13th week, rats from all three lines, with a ranking of LAD-1 > NP > LAD-2, were drinking more ethanol (3.3, 2.2, and 2.0 g/kg/day, respectively) compared with their consumption during the first week of access (,1.1 g/kg/day for all three lines). Conclusion: These data indicate that access to multiple concentrations of ethanol and exposure to multiple deprivation cycles can partially overcome a genetic predisposition of NP, LAD-1, and LAD-2 rats for low alcohol consumption. In addition, the findings suggest that genetic control of low alcohol consumption in rats is not associated with the inability to display an ADE. [source] Detection of access to terror-related Web sites using an Advanced Terror Detection System (ATDS)JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 2 2010Yuval Elovici Terrorist groups use the Web as their infrastructure for various purposes. One example is the forming of new local cells that may later become active and perform acts of terror. The Advanced Terrorist Detection System (ATDS), is aimed at tracking down online access to abnormal content, which may include terrorist-generated sites, by analyzing the content of information accessed by the Web users. ATDS operates in two modes: the training mode and the detection mode. In the training mode, ATDS determines the typical interests of a prespecified group of users by processing the Web pages accessed by these users over time. In the detection mode, ATDS performs real-time monitoring of the Web traffic generated by the monitored group, analyzes the content of the accessed Web pages, and issues an alarm if the accessed information is not within the typical interests of that group and similar to the terrorist interests. An experimental version of ATDS was implemented and evaluated in a local network environment. The results suggest that when optimally tuned the system can reach high detection rates of up to 100% in case of continuous access to a series of terrorist Web pages. [source] Understanding Disparities in Transplantation: Do Social Networks Provide the Missing Clue?AMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2010K. Ladin Although the National Organ Transplant Act calls for equity in access to transplantation, scarcity and racial disparities persist. To date, even the most comprehensive models have been unable to adequately explain these racial disparities, leaving policymakers unsure how best to intervene. Previous individual-level analyses, which have implicated risk factors such as race, financial status, cultural beliefs, unemployment, lack of commitment to surgery and lack of continuous access to care, overlook contextual and social network exposures. Social networks present a compelling way to examine cumulative risk clustered across individuals. Social networks have been shown to influence health outcomes and health behaviors through various pathways, including shared social capital, engaging in similar or group risky behaviors, diffusion of information and adopting or propagating social norms. Precursors to chronic kidney disease, including obesity, have been shown to spread through social networks. Social network analysis can reveal shared risks between potential donors and recipients in a given network, clarifying the likelihood of finding an appropriate match through either direct donation or paired exchanges. This paper presents a novel application of social network analysis to transplantation, illustrating implications for disparities and future clinical interventions. [source] Isolating the evocative and abative effects of an establishing operation on challenging behaviorBEHAVIORAL INTERVENTIONS, Issue 3 2006Mark F. O'Reilly Establishing operations (EO) influence operant responding by altering the reinforcing effectiveness of consequences (reinforcer establishing or abolishing effect) and changing the frequency of behavior that has been reinforced by those consequences in the past (evocative or abative effect) (Michael, 1982, 1993). In this study we attempted to isolate the evocative and abative effects of an EO for positively reinforced challenging behavior with a person with autism and developmental disabilities. The study consisted of three phases. First, an analogue functional analysis identified attention as maintaining challenging behavior. Second, access to attention was systematically controlled (continuous access versus no access) immediately prior to functional analysis sessions in which the participant received attention on an FR1 schedule. Results of this phase indicated that challenging behavior occurred at higher levels during the functional analysis sessions when access to attention was restricted immediately prior to sessions (i.e., no access appeared to function as an EO). In the third phase, prior access to attention was again controlled as in the second phase of the study, however the participant was then placed on extinction. The results of this final phase seem to indicate that no access to the reinforcer prior to extinction had an evocative effect (produced high levels of responding) whereas access to the reinforcer had an abative effect (produced lower levels of responding) during extinction sessions. Copyright © 2006 John Wiley & Sons, Ltd. [source] The efficacy of noncontingent reinforcement as treatment for automatically reinforced stereotypyBEHAVIORAL INTERVENTIONS, Issue 2 2002Lisa N. Britton Noncontingent reinforcement (NCR), in the form of continuous access to preferred leisure items, has recently been reported as a successful treatment for automatically reinforced aberrant behavior. However, previous research has shown that the outcome of such procedures can be compromised under certain circumstances, such as when the response effort required to access leisure items is increased. The purpose of the current study was to assess the efficacy of two variations of NCR as treatment for automatically reinforced stereotypy. In the first phase of the study, functional analyses revealed that the stereotypy of three individuals with developmental disabilities was maintained independent of social consequences. A sensory class assessment was then conducted to identify the specific sensory products that appeared to maintain the behaviors. Finally, we evaluated the effects of NCR (using stimuli identified in the previous assessments) under two conditions. In the first condition, the leisure item was made freely available, by placing it on the table in front of the participant. In the other condition, an experimenter prompted the participant to interact with the leisure item at the beginning of the session. The results indicated that NCR successfully competed with stereotypy only when participants were prompted to interact with the leisure item. These findings are discussed in the context of developing NCR interventions for automatically reinforced aberrant behavior. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||