Lack of depression-like effects of saccharin deprivation in rats: Forced swim test, differential reinforcement of low rates and intracranial self-stimulation procedures.

In humans and laboratory animals, drug withdrawal often is associated with depression-like behaviors. In the present study, rats had unlimited free-choice access to water and a saccharin-containing solution before being subjected to repeated episodes of saccharin deprivation. Saccharin deprivation (1) reduced immobility time in the forced swim test, (2) increased reinforcement rate in rats trained to lever-press under the differential reinforcement of a low-rate (72-sec) schedule of food reinforcement, and (3) lowered intracranial self-stimulation thresholds in a discrete-trial current titration procedure. Taken together, these findings suggest that deprivation from a nondrug reinforcer, saccharin, is not associated with depression-like behaviors. In contrast, saccharin-deprived rats demonstrated improved performance in the behavioral paradigms used here. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-administration of ethanol and saccharin in newborn rats: Effects on suckling plasticity.

Responsiveness to a surrogate nipple providing water, saccharin, 5% ethanol, or 10% ethanol was tested in newborn rats naive to suckling (3–5 hr old) on Postnatal Day (P) 0 and in older neonates with regular suckling experience on P1 or P2. At all ages, pups demonstrated greater nipple attachment for saccharin or 5% ethanol than for water. Intake of saccharin and 5% ethanol was high in newborns, far exceeding that of water. At P1 and P2, pups exhibited a preference for saccharin, but not for 5% ethanol. Preexposure to a nipple providing ethanol or saccharin (but not a nipple alone or fluids alone) increased subsequent responsiveness toward an empty surrogate nipple (no fluid), both 1 hr and 24 hr after preexposure. Although, during preexposure, pups responded most positively to the nipple providing saccharin, the longest time spent on an empty nipple was observed in pups preexposed to 10% ethanol. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Using Behavioral Theories of Choice to Predict Drinking Outcomes Following a Brief Intervention.

Behavioral theories of choice predict that substance use is partly a function of the relative value of drugs in relation to other available reinforcers. This study evaluated this hypothesis in the context of predicting drinking outcomes following an alcohol abuse intervention. Participants (N=54, 69% female, 31% male) were college student heavy drinkers who completed a single-session motivational intervention. Students completed a baseline measure of substance-related and substance-free activity participation and enjoyment. Only women showed a significant reduction in drinking at the 6-month follow-up, and the ratio of substance-related to substance-free reinforcement accounted for unique variance in their drinking outcomes. Women who at baseline derived a smaller proportion of their total reinforcement from substance use showed lower levels of follow-up drinking, even after the authors controlled for baseline drinking level. Male and female participants who reduced their drinking showed increased proportional reinforcement from substance-free activities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A physiological effect of cognitive dissonance under stress and deprivation.

An experiment and a partial replication were conducted to relate the change of motivation due to dissonance reduction and commitment to physiological changes. The experimental technique was based on food deprivation studies by Brehm which showed that already deprived individuals who committed themselves to further fasting under conditions of low reward decreased their self-estimates of hunger, while the reverse was true for those given high rewards. The data suggest that a person who has convinced himself that he is not so hungry tends to respond physiologically as if he were not hungry. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of gestational ethanol exposure on voluntary ethanol intake in early postnatal and adult rats.

Clinical and epidemiological studies provide strong data for a relationship between prenatal ethanol exposure and the risk for abuse in adolescent and young adult humans. However, drug-acceptance results in response to fetal exposure have differed by study, age at evaluation, and experimental animal. In the present study, the authors tested whether voluntary ethanol intake was enhanced in both the infantile and adult rat (15 and 90 days of age, respectively), as a consequence of chronic fetal drug experience. Experimental rats were exposed in utero by administering ethanol to a pregnant dam in a liquid diet during gestational Days 6-20. Compared with those for isocaloric pair-fed and ad lib chow control animals, the results for experimental animals demonstrated that fetal exposure significantly increased infantile affinity for ethanol ingestion without affecting intake patterns of an alternative fluid (water). Heightened affinity for ethanol was absent in adulthood. Moreover, the results argue against malnutrition as a principal factor underlying the infantile phenomenon. These data add to a growing literature indicative of heightened early postnatal acceptance patterns resulting from maternal use or abuse of ethanol during pregnancy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Relative Effectiveness of Instructions, Agreements, and Reinforcement in Behavioral Contracts with Alcoholics": Erratum.

Reports an error in the article "Relative Effectiveness of Instructions, Agreements, and Reinforcement in Behavioral Contracts with Alcoholics" by Peter M. Miller, Michel Hersen, and Richard M. Eisler in the October 1974 issue. The affiliation for Michel Hersen should be changed to read: Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.(The following abstract of this article originally appeared in record 1975-03756-001). Evaluated the effects of the components of behavioral contracting on drinking in 40 chronic alcoholics. Ss were divided into 4 groups matched on age, education, length of problem drinking, and initial operant drinking responses. They were then exposed to 1 of the following conditions: (a) verbal instructions to limit alcohol consumption, (b) signed written agreement to limit consumption, (c) verbal instructions plus reinforcement for compliance, and (d) signed agreement plus reinforcement. Pre- and postoperant analog drinking sessions, in which leverpressing was reinforced with alcohol on a fixed ratio reinforcement schedule, served to assess effects of the experimental conditions. Results indicate that while instructions and signed agreements had limited influence on drinking, both groups receiving reinforcement for compliance significantly decreased their operant drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maternal Experience Produces Long-Lasting Behavioral Modifications in the Rat.

From 5 to 22 months of age, cognitive and emotional responses of nulliparous, primiparous, and multiparous rats were assessed using a dry land maze (DLM) and an elevated plus-maze (EPM) at 4-month intervals. Parous rats exhibited improved spatial memory in the probe and competitive versions of the DLM, and more exploration in the EPM and a novel stimulus test relative to nulliparous females. The nulliparous females, however, outperformed parous rats during the DLM visual cue test at 17 months of age. At 23 months, no differences in stressed corticosterone levels or Golgi-stained hippocampal neurons were observed. Thus, cognitive and emotional modifications were observed in parous rats; the neurobiological mechanisms for these enduring effects, however, remain to be identified. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Haloperidol attenuates rewarding and aversively conditioned suppression of saccharin solution intake: Reevaluation of the anhedonia hypothesis of dopamine blocking.

The dopamine (DA) antagonist, haloperidol, affected the conditioned suppression of a saccharin solution intake (the conditioned stimulus, CS) induced by amphetamine (AMPH) and lithium chloride (LiCl) unconditioned stimuli (USs). Four experiments showed that (a) haloperidol by itself did not reduce saccharin solution intake. (b) When haloperidol was injected between the CS and the US, the conditioned suppression was attenuated; however, (c) this did not occur when haloperidol was injected after the US, indicating that haloperidol affected the perception of the US. (d) This attenuation was found with both rewarding AMPH and aversive LiCl treatments, indicating that the valence of the US was unimportant. Thus, the so-called "anhedonia response" might be due to weakening of US impact. A general salient-stimulus hypothesis was proposed, with the anhedonia hypothesis of DA blocking as its subset. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Choline supplementation following third-trimester-equivalent alcohol exposure attenuates behavioral alterations in rats.

Despite the known adverse consequences of prenatal alcohol exposure, some pregnant women continue to drink alcohol, making it imperative to identify treatments for children with fetal alcohol spectrum disorders. The authors recently reported that perinatal choline supplementation can reduce some fetal alcohol effects (J. D. Thomas, M. Garrison, & T. M. O'Neill, 2004), and the present study examined whether choline supplementation is effective when administered after third-trimester-equivalent ethanol treatment. Rat pups were exposed to 6.0 g/kg/day ethanol during the neonatal brain growth spurt (Postnatal Days [PD] 4-9) and treated with choline chloride (0, 10, 50, or 100 mg/kg) from PD 10-30. Behavioral testing occurred after choline treatment had ceased. Female subjects exposed to ethanol were overactive and exhibited spatial learning deficits, effects that were attenuated with all doses of choline supplementation. These data indicate that choline supplementation can alter brain development following a developmental insult. Moreover, the data suggest that early dietary interventions may reduce the severity of some fetal alcohol effects, even when administered after birth. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of caloric, protein, and sodium deprivation on the affiliative behavior of Norway rats (Rattus norvegicus).

The tendency of food-deprived, protein-deprived, and sodium-deprived Norway rats (Rattus norvegicus) and their respective controls to affiliate with conspecifics deprived of either food, protein, or sodium was examined. We found that (a) independent of internal state, focal rats offered a forced choice between protein-deprived and protein-replete target rats spent more time near replete than deprived target rats; and (b) both food-deprived and sodium-deprived focal rats offered a forced choice between food-deprived and replete target rats spent less time near fasted rats than did well-fed and sodium-replete focal rats. The data indicate that (a) rats can distinguish both food-deprived and protein deprived rats from replete rats and (b) the deprivation states of rats can affect their willingness to affiliate with deprived conspecifics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of acute and prolonged opiate abstinence on extinction behaviour in rats.

We examined the role of withdrawal in relapse to drug-seeking and drug-taking by testing the effects of opiate abstinence on extinction behaviour in rats trained to self-administer heroin. Male Long-Evans rats responded for IV heroin under a heterogeneous chain (VI 120 s; FR 1) schedule in which "seeking" responses preceded a "taking" response which produced a drug infusion. Responding was then measured in extinction during acute (6, 12, and 24 hr) and prolonged (3, 6, 12, and 25 day) abstinence. Sucrose consumption and somatic withdrawal were assessed at each testing period. During acute abstinence, responses on the "drug-seeking" manipulandum increased at 24 hr, whereas responses on the "drug-taking" manipulandum increased at 6 hr. Both responses were elevated during the 12-day abstinence test. Sucrose consumption was reduced and somatic withdrawal scores were increased in opiate-experienced rats at each test period. Results suggest that heroin abstinence has different effects on drug-seeking and drug-taking and that these effects do not temporally coincide with somatic measures of opioid withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral philosophy in the late 1980’s.

Division 25 (Experimental Analysis of Behavior) is composed of about 1500 behaviorally-oriented psychologists, both applied and basic. It is one of the few divisions defined not by a specific sub-content area of psychology, but by an approach to the whole of psychology. In this sense, Division 25 is probably one of the most philosophically-oriented of all the divisions in APA: the majority of its members are more or less comfortable with behavioral philosophy. Of course, some of our members are not at all philosophically oriented, and are members because of their attraction to behavioral techniques, methodology, or to specific behavioral theories. Further, due to the history of behavioral analysis, there are fundamental disagreements about the nature of behaviorism among behaviorists. Thus, the remainder of what I will say in this paper should be thought of merely as my personal opinion—not as a statement on behalf of the Division. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Multiple Factors in Short-Term Behavioral Control of Protein Intake in Rats.

The availability and concentration of dietary protein was varied in an examination of the nature of the day-to-day intake of protein solutions by 60-day-old male rats. It was found that the rats consumed a remarkably constant absolute amount of protein each day, adjusting overall caloric intake to maintain protein at a roughly constant proportion of total calories. Factors such as the time of access to a protein source or the extent of prior experience with a protein source were seen to influence the overall constancy of protein intake, whereas daily shifts in preference between two available concentrations of protein did not interfere with such short-term control. The mechanism for this behavioral control is likely to be different from mechanisms mediating the conditioned response to dietary protein, as in the response to dietary amino acid imbalance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral characterization of amygdala involvement in mediating intra-accumbens opioid-driven feeding behavior.

The present experiments were conducted to provide a more detailed behavioral analysis of the dissociable roles of the basolateral (BLA) and central nucleus (CeA) of the amygdala in mediating intra-accumbens (Acb) opioid-induced feeding of a high-fat diet. Confirming previous findings, temporary inactivation of the CeA with the GABAA agonist muscimol reduced DAMGO (D-Ala2-NMe-Phe4-Glyol5-enkephalin)-induced and baseline food intake, whereas intra-BLA muscimol selectively blocked only DAMGO-induced food intake, leaving baseline feeding intact. However, although inactivation of the BLA reduced DAMGO-induced food intake to control levels, this treatment led to exaggerated number and duration of food hopper entries after food intake had ended. A subsequent experiment under conditions of limited access to the diet found the identical pattern of behavior following intra-Acb administration of DAMGO, regardless of whether the BLA was inactivated. Last, BLA inactivation was shown to have no influence on feeding driven by a state of negative-energy balance (24-hr food deprivation), demonstrating a specific influence of the BLA on opioid-driven feeding. These findings suggest that BLA mediates palatability-driven feeding and that this influence is particular to the consummatory act of ingestion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

One night of total sleep deprivation impairs implicit learning in the serial reaction task, but not the behavioral expression of knowledge.

Implicit sequence learning in the serial reaction task suffers from total sleep deprivation. The authors compared implicit-learning scores in a sleep-deprivation (SD) group (n = 12) and a control group (n = 6). Both groups were tested immediately after learning a 1st sequence; a delayed test was conducted on the next day (after a night without sleep in the SD group). Immediately after the delayed test a 2nd sequence was learned, followed by an immediate test and a delayed test toward the end of the experiment. In the SD group implicit-learning scores were reduced in both tests of the 2nd sequence, but in neither test of the 1st sequence. Thus, 1 night of total sleep deprivation impairs the acquisition of implicit sequence knowledge, but not its behavioral expression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Yoked delivery of cocaine is aversive and protects against the motivation for drug in rats.

In Experiment 1, water-deprived rats had 5-min access to saccharin followed by active or yoked intravenous delivery of saline or cocaine (0.33 mg/infusion). Both cocaine groups avoided intake of the saccharin cue following saccharin–cocaine pairings; however, the rats in the yoked condition exhibited greater avoidance of the taste cue than did the actively administering rats. Experiment 2 evaluated subsequent self-administration behavior on fixed- and progressive-ratio schedules of reinforcement. The results showed that prior yoked exposure to cocaine reduced subsequent drug-taking behavior on a progressive-ratio but not on a fixed-ratio schedule. Finally, Experiment 3 used a choice test to determine the impact of yoked drug delivery on the relative preference for cocaine versus water. The results showed that rats with a history of self-administering cocaine preferred to perform operant behaviors on the side of the chamber previously paired with cocaine, whereas the rats with a history of yoked delivery of cocaine avoided this side. These data show that, in most rats, the unpredictable, uncontrollable delivery of cocaine protects against the subsequent motivation for cocaine through an aversive mechanism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conditioned Inhibition of Cocaine Seeking in Rats.

Despite its potential relevance to the treatment of drug abuse, conditioned inhibition of drug seeking has not been systematically investigated before. In this study, rats could self-administer cocaine by lever pressing whenever a click or tone was present. Responding was not reinforced when a light was present. The light was presented simultaneously with the click (i.e., in an excitatory context) in 1 group, but the light was always presented alone in another group. When it was later presented in compound with the tone, the light was a highly effective conditioned inhibitor, suppressing cocaine seeking by 92% in the former group and by 74% in the latter. These results suggest ways to improve cue-oriented behavioral treatments for drug abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Buffering effect of religiosity for adolescent substance use.

This research examined the hypothesis that religiosity buffers the impact of life stress on adolescent substance use. Data were from a sample of 1,182 participants surveyed on 4 occasions between 7th grade (mean age = 12.4 years) and 10th grade. Religiosity was indexed by Jessor's Value on Religion Scale (R. Jessor & S. L. Jessor, 1977). Zero-order correlations showed religiosity inversely related to alcohol, tobacco, and marijuana use. Significant Life Events×Religiosity buffer interactions were found in cross-sectional analyses for tobacco, alcohol, and marijuana use. A latent growth analysis showed that religiosity reduced the impact of life stress on initial level of substance use and on rate of growth in substance use over time. Implications for further research on religiosity and substance use are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral effects of intracerebroventricular microinfusion of agmatine in adult rats.

The present study investigated the behavioral effects of intracerebroventricular microinfusion of agmatine. Rats with low dose (10 μg), but not high dose (100 μg), of agmatine spent significantly less time in the enclosed arm and more time in the open arm in the elevated plus maze. In the water maze task, the high dose group displayed a transient impairment in searching for a hidden platform, whereas the low dose group had reduced latency in the first probe test. In the object recognition task, all groups could detect the novel object, but the low dose group spent significantly more time exploring displaced objects. Furthermore, the low dose group made significantly fewer errors in the working, but not the reference, memory version of the radial arm maze task. These results suggest that the behavioral effects of agmatine are task- and dose-dependent, and agmatine may be an anxiolytic and memory modulator. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ethanol Palatability and Consumption by High Ethanol-Drinking Rats: Manipulation of the Opioid System With Naltrexone.

Three experiments examined the effect of acute naltrexone treatment on both taste reactivity and consumption of ethanol in high ethanol-preferring rat lines: Alko Alcohol-Accepting (AA) rats (Experiments 1 and 2) and Alcohol-Preferring (P) rats (Experiment 3). A 3.0 mg/kg naltrexone dose was ineffective at altering ethanol palatability for either line, whereas 7.5 mg/kg was effective at reducing palatability of 10% ethanol for AA, but not P, rats, as reflected by both a decrease in ingestive responding and an increase in aversive responding. The effects of naltrexone on ethanol consumption were quite consistent: At both dosages, acute naltrexone treatment significantly decreased consumption of 10% ethanol. Termination of naltrexone resulted in an immediate increase in ethanol consumption to control levels. Results show that ethanol palatability and consumption can be dissociated in the rat and that the organization of opioidergic mechanisms that mediate ethanol responses may vary between rat lines. (PsycINFO Database Record (c) 2010 APA, all rights reserved)