PubMed Health⌕ Search

Biomedical subjects

R N Ehrman

Publications and source records attributed to R N Ehrman.

18 recordsLinked to original sources
PubMed1998

Cocaine use is associated with increased craving in outpatient cocaine abusers.

Sixty-one cocaine abuse patients provided self-reports of craving and urine samples 3 times a week. Within-subject analyses revealed several relationships between the measures. First, peak craving levels were higher for 2-3-day intervals during which cocaine use had occurred than for preceding or following abstinent intervals. Second, average craving ratings during cocaine use intervals were double the ratings given during abstinent intervals. Third, cocaine use was 4 times more likely to occur during a period of elevated craving than during comparison intervals. Finally, participants who provided at least 1 positive urine sample reported more craving increases over 4 weeks than did abstinent individuals. These results demonstrate a strong association between craving increases and naturally occurring cocaine use but do not allow a determination of whether craving caused cocaine use or cocaine use caused craving.

Adult↗
PubMed1997

Comparing self-reported cocaine use with repeated urine tests in outpatient cocaine abusers.

Sixty-one participants in outpatient therapy for cocaine dependence provided urine samples and self-reports of cocaine use 3 times a week for 4 weeks. Participants later gave a retrospective self-report of cocaine use for the month on the addiction Severity Index (ASI). Comparisons with urine test values revealed substantial underreporting of cocaine use on both measures, and results from the 2 forms of self-report were only imperfectly correlated. More participants admitted to at least 1 cocaine use episode on the ASI than on the repeated self-reports, but the repeated reports provided a more accurate index of the relative frequency of cocaine use during the month. Self-reports can enhance cocaine use detection when urines are infrequently collected and can help determine whether consecutive positive urine samples represent elevated metabolite levels from a single drug use episode. However, self-reports cannot substitute for regular urine sampling.

Adult↗
PubMed1996

Failure of ritanserin to block cocaine cue reactivity in humans.

As part of a double-blind placebo-controlled study of the effects of ritanserin on cocaine use and craving, reactivity to cocaine-related events was assessed both before and during medication. Twenty-two patients receiving ritanserin and 23 receiving placebo were exposed to cocaine cues while continuous measures of heart rate, skin temperature, and skin resistance were taken. Self-reports of high, withdrawal, and craving were also collected. The cues produced significant physiological responding as well as significant increases in high and craving during both sessions. Ritanserin reduced cue-elicited decreases in skin temperature, but had no effect on heart rate and skin resistance or on cue-induced high and craving. The results demonstrate that cue reactivity is a robust phenomenon across two assessment sessions but fail to support the use of ritanserin as a means of reducing cue-elicited drug states.

Arousal↗
PubMed1994

Reliability and validity of 6-month timeline reports of cocaine and heroin use in a methadone population.

Fifty-nine persons addicted to heroin and maintained by methadone reported on daily heroin and cocaine use during 2 timeline calendar interviews administered 6 weeks apart. Retrospective reports covering 6 months were compared with urine samples taken weekly during the interval. Test-retest correlations were high and timeline estimates of drug use frequency were significantly correlated with the frequency of drug-positive urine results. Thus, timeline reports of drug-use frequency appeared both reliable and valid. Individual participants either over- or under-reported by an average of about 15%, and they did not identify instances of drug use with greater than chance accuracy when particular episodes of drug use occurred. These results support the use of timeline reports to make group comparisons of long-term drug use, but suggest that timeline data should not be used to identify specific drug-use episodes. Work with other drug-use population is necessary to extend these conclusions.

Adult↗
PubMed1993

Cue reactivity and cue reactivity interventions in drug dependence.

Despite a venerable history dating back to Pavlov and countless testimonials from patients such as those in the opening paragraphs of this chapter, there is much that remains to be learned about drug signals and, particularly, about ways of reducing their adverse effects on human drug users. There is a substantial amount of data showing increased craving and signs of physiological arousal to drug-related versus neutral cues in drug users for both drug classes reviewed here. Additional controlled studies will be useful in refining which responses among those studied are, in fact, conditioned in origin and therefore can be subjected reasonably to learning-based interventions. Most attempts to modify cue responsivity for clinical benefit have met with only modest success, and there is ample room for creative, but controlled, treatment-outcome studies. In recent years, several other groups have joined in the effort to understand drug-related cue reactivity, extending the research area to alcohol and nicotine (Monti et al. 1987; Niaura et al. 1988, 1989; Cooney et al. 1984; Hodgson and Rankin 1982; Drummond 1990; Laberg 1990). The interested reader is referred to several additional reviews of cue reactivity and cue exposure research related to alcohol and nicotine (Niaura 1988; Drummond 1990; Laberg 1990), opiates (Powell 1990), opiates and cocaine (Childress et al. 1988b; O'Brien et al. 1990), and all the preceding areas (Rohsenow et al. 1991).

Behavior Therapy↗
PubMed1992

Conditioned responses to cocaine-related stimuli in cocaine abuse patients.

Subjects with a history of free-basing and smoking cocaine but no history of opiate injections were exposed to three sets of stimuli. They received cocaine-related stimuli in one session, opiate-related stimuli in a second session, and non-drug stimuli on a third occasion. Compared to the opiate and non-drug cues, the cocaine-related events caused reliable decreases in skin temperature and skin resistance, and reliable increases in heart rate, self-reported cocaine craving, and self-reported cocaine withdrawal. Furthermore, control subjects lacking a history of cocaine or opiate use failed to show such differential responding. These results suggest that cocaine-related stimuli evoke Pavlovian conditioned responses in cocaine abuse patients. Such findings encourage continuing efforts to develop drug treatment strategies based on conditioning principles.

Adult↗
PubMed1992

Designing studies of drug conditioning in humans.

There has been much recent interest in the possibility that signals for drug use in humans acquire the ability to evoke classically conditioned (learned) states which motivate drug taking. Much data now suggest that cues paired with drug use come to elicit physiological responses and subjective reports of drug-related feelings like craving and withdrawal. However, the designs employed do not permit the conclusion that the observed responding results from classical conditioning. Studies which look directly at conditioning in the laboratory by pairing neutral stimuli with drug administration have not provided appropriate controls for unlearned effects such as sensitization or pseudo-conditioning. Similarly, studies which assess responding to cues thought to signal drug use in the natural environment (e.g., the sight of someone injecting heroin) have not adequately assessed whether such cues have unconditioned (unlearned) effects. Determining whether responding to drug-related cues results from classical conditioning has important implications for the development of drug treatments. Consequently, the purpose of the present review is to outline a set of criteria for determining that responses to drug-related stimuli in humans are learned. Existing studies are reviewed in light of these criteria and paradigms for further work are suggested.

Conditioning, Classical↗
PubMed1986

Opiate receptors, neuropeptides in CNS and CSF of two Macaca species with different responsiveness to opiates.

Of two related Macaca species, the rhesus (M. mulatta), acquires opiate tolerance and dependence more readily than the cynomolgus (M. fascicularis). In the cynomolgus, mu-opiate receptors were significantly fewer in the caudate nucleus and globus pallidus; delta-sites were fewer in the thalamus. kappa-Sites showed no species difference. The levels of [Met5]enkephalin, substance P and dynorphin B in various brain areas were comparable. On the other hand, receptor-assayed endorphin activity was higher in CSF of cynomolgus than rhesus monkeys.

Animals↗
PubMed1985

Nondependent monkeys self-administer hydromorphone.

Four monkeys, 2 rhesus and 2 cynomolgus, were trained to perform a multiple fixed-ratio extinction (MULT/FR/EXT) schedule for banana pellets. Subsequently, all animals were given hydromorphone (HYM) self-administration training, which consisted of substitution of FR (fixed ratio) 2 cocaine for FR 80 banana pellets and substitution of FR 2 HYM for FR 2 cocaine. All of the animals acquired cocaine self-administration. They also acquired HYM self-administration when it was substituted for cocaine. Next, 50 HYM self-maintenance sessions were given. During these sessions, animals were allowed to self-administer a total cumulative dose of 1 mg/kg/day of HYM. The animals were observed for spontaneous withdrawal while they performed an operant for food 24 and 48 hr after their last maintenance dose of HYM. Because none of the monkeys showed signs of spontaneous withdrawal or disruption of the appetitive baseline during the first postmaintenance appetitive session, a 0.4-mg dose of naloxone was administered noncontingently to test for precipitated withdrawal. Naloxone disrupted appetitive responding for banana pellets in the 2 rhesus monkeys. Naloxone had no effect on responding for food in the cynomolgus monkeys. Because none of the monkeys showed signs of spontaneous withdrawal or disruption of their appetitive baseline during the second postmaintenance session, a HYM challenge dose of 1 mg/kg was given noncontingently to assess whether tolerance to the daily maintenance dose had been acquired. The bolus dose of HYM suppressed lever pressing for food in both species, a result indicating a lack of tolerance. These results suggest that the positive reinforcing properties of HYM are sufficient to maintain opioid self-administration and that tolerance and physical dependence are not necessary.

Animals↗
PubMed1984

Use of naltrexone to extinguish opioid-conditioned responses.

Opioid use generates many conditioned responses associated with the sights, sounds, smells, and rituals experienced during addiction. Environmental stimuli alone can provoke withdrawal symptoms and contribute to relapses in treated patients. The use of naltrexone in a program designed to progressively extinguish conditioned drug responses is described. Since naltrexone effectively blocks opiate effects at the receptor level, heroin injections produce no euphoria. Unreinforced self-injections diminish the responses learned during the period of drug abuse and protect the patient from rapid readdiction. Patients are confronted with a hierarchical set of drug-related stimuli and taught a muscular relaxation procedure to relieve arousal and discomfort. The continued administration of naltrexone, the self-induced relaxation response, and the repeated presentation of drug-related stimuli result in the eventual diminution or extinction of the arousal properties of the imagery and environmental stimuli associated with addiction.

Adult↗
PubMed1984

Salt hunger in the rhesus monkey.

Five rhesus monkeys (Macaca mulatta) were placed on a low-sodium diet and given injections of furosemide in order to promote sodium loss. The results indicated that these methods elicit a substantial and specific salt hunger. Issues surrounding salt hunger are discussed.

Animals↗
PubMedDate not supplied

Using cue reactivity to screen medications for cocaine abuse: a test of amantadine hydrochloride.

The use of responding to drug-related stimuli as a dependent measure for studies of anticraving medications was assessed. Cocaine-dependent subjects receiving either amantadine hydrochloride, a putative anticraving agent, or placebo were exposed to drug-related cues prior to and 7 days after the initiation of the medication. Measurements of heart rate, skin resistance, skin temperature, and self-reported craving were taken during each stimulus session. Amantadine increased physiological reactivity to the drug-related cues compared to the placebo while having no effect on craving. Although the results discourage the use of amantadine as an anticraving medication, they do suggest that responses elicited by drug-related stimuli provide a valuable set of dependent measures for use in future medication trials of anticraving agents.

Adult↗
PubMedDate not supplied

Effect of smoking cues and cigarette availability on craving and smoking behavior.

This study examined whether smokers respond differently to smoking cues than to affectively neutral or unpleasant cues without smoking content, and whether reactivity is affected by expectations regarding the opportunity to smoke. Expectancy was manipulated by telling subjects in group SMOKE that they could smoke, and subjects in group NO SMOKE that they could not smoke following each cue-reactivity session. The dependent variables were subjective ratings of "desire to smoke", "high", "withdrawal", and mood, as well as latency to initiate smoking measured in group SMOKE. Statistical analyses demonstrated that only group SMOKE (a) reported greater "desire to smoke" and "withdrawal" to the smoking cues compared to the baseline, (b) reported greater "desire to smoke" to the smoking cues than to the unpleasant or to the neutral cues, and (c) smoked faster after the smoking cues than after the neutral cues. Both groups rated the unpleasant cues as affectively more negative than the neutral cues. The data suggest that the impact of drug-cues on craving and subsequent drug-use is due to their drug-related content, and not to negative affect. Furthermore, the impact of drug-related cues appears to be influenced by perceived drug-availability.

Adolescent↗
PubMedDate not supplied

Relationships among physiological and self-report responses produced by cocaine-related cues.

In response to cocaine cues, 150 subjects with a history of cocaine abuse showed decreases in skin temperature and skin resistance and increases in heart rate and reported craving, high, and withdrawal responses. These responses were consistent across four years of data collection. Craving reports were not consistently associated with either high or withdrawal responses, and many subjects endorsed increases in both high and withdrawal states. Correlations revealed no pattern of association among physiological variables and responding did not differ between subjects who did and those who did not report increases in each of the drug states. Finally, physiological variables did not predict reported drug states in discriminant analyses. Cocaine cue reactivity cannot be easily related to a unitary state of high, withdrawal, or craving. It is suggested that future studies focus more on the prediction and measurement of treatment outcome than on the form of cue responses.

Adult↗