Psychophysiological effects of alcohol-related stimuli.
Explore the source record for details and available documents.
Adult↗
Biomedical subjects
M L Stitzer
Publications and source records attributed to M L Stitzer.
Altered dose incentive procedures: effects on polydrug use among methadone maintenance patients.
Explore the source record for details and available documents.
Adult↗
Human cigarette smoking: effects of puff and inhalation parameters on smoke exposure.
This study determined effects of three smoking behavior components: puff volume, inhalation volume and lung exposure duration on biological measures of smoke exposure. A microcomputer-based auditory feedback system allowed subjects (N = 9 or 10 per experiment) to control puff and inhalation parameters as they smoked usual brand cigarettes. In each of four experiments, one smoking parameter was manipulated across sessions while two other parameters were held constant. Biological samples were obtained before and after each 8-puff smoking session conducted under a given set of behavioral parameters for analysis of plasma nicotine and expired air carbon monoxide (CO) levels. In Experiment I, both nicotine and CO levels were influenced systematically as puff volume was varied from 15 to 60 ml (inhalation volume = 50% of vital capacity, lung exposure time = about 9 sec). Nicotine boost (post- minus presession levels) increased 4-fold and CO boost increased 9-fold over this range of puff volume values. In Experiment II, nicotine levels were unaffected when average lung exposure times varied from 5 to 21 sec (puff volume = 50 ml, inhalation volume = 50% of vital capacity), suggesting that all the nicotine available may be absorbed during a normal smoking inhalation cycle with no breathholding. CO levels increased systematically with longer breathholds. In Experiments III and IV, inhalation volumes from 10% and 20% to 60% of vital capacity had no effect on either nicotine or CO levels, and this was true whether lung exposure time was about 8 sec (Experiment III) or about 4 sec (Experiment IV). This series of studies has shown that puff volume is an important determinant of tobacco smoke exposure, but that inhalation components of smoking behavior, at least within the range of parameters tested, have no effect on nicotine exposure levels.
Adult↗
Acute marijuana effects on social conversation.
The present study assessed the acute effects of smoked marijuana on social conversation. Speech quantity was recorded continuously in seven moderate marijuana users during separate 1 h experimental sessions following the paced smoking of 0, 1.01, 1.84, and 2.84% THC marijuana cigarettes. Subjects engaged in conversation with undrugged partners who smoked placebo marijuana cigarettes. The active marijuana produced significant decreases in speech quantity, increases in heart rate, and increases in self-reports of "high" and sedation. Partners showed no effects in speech quantity or self-reports of drug effects that were systematically related to the doses administered to the subject pair members. The effects on speech quantity observed in the present study after acute dosing are similar to the effects on social conversation reported previously during chronic marijuana dosing. Marijuana appears to be an exception to the general rule that drugs of abuse increase verbal interaction.
Adult↗
Cigarette filter vent blocking: effects on smoking topography and carbon monoxide exposure.
Two studies were conducted using smokers of unventilated cigarettes to determine the effects of filter vent blocking on smoke exposure (Experiment 1) and smoking topography (Experiment 2). In both studies, subjects were exposed to ultra low yield cigarettes that had 0%, 50%, and 100% of their filter vents blocked with tape. In Experiment 1, carbon monoxide (CO) exposure from eight 60 ml puffs increased in an orderly fashion as a function of filter vent blocking. By blocking filter vents, smoke was no longer diluted with air as it passed through the filter, and hence, exposure to smoke constituents was increased. In Experiment 2, when puff and inhalation parameters were allowed to vary, subjects took significantly more puffs, and larger puffs from unblocked cigarettes than from completely blocked cigarettes, but CO exposure from the completely blocked cigarette was double that from the unblocked cigarette (8.96 ppm vs. 4.32 ppm). The increased number and volume of puffs taken from ultra low yield cigarettes with unblocked filter vents may be due to changes in physical characteristics of the cigarette, and not to smokers actively compensating for reduced smoke constituent yields.
Adult↗
Effect of puff size instructions on puff volume.
In two experiments, the flexibility of puff volume was assessed using instructions and feedback to manipulate volume. Also, the effects of altered puff volume on puff duration, puff peak flow, and carbon monoxide (CO) boost were examined. In the first experiment, subjects were told to take small, medium, and large puffs. Subjects were able to accurately follow the puff size instructions; they took different-size puffs by altering their puff durations. In the second experiment, when puff duration was controlled, subjects were able to follow the puff size instructions by altering the intensity of their puffs. These two experiments demonstrated that a wide range of puff volumes can be generated by instructional control and that volume changes can result either from alterations of puff duration or of puff intensity.
Adult↗
Choice of blind methadone dose increases by methadone maintenance patients.
In the present study, a choice procedure was used in an outpatient methadone maintenance clinic to examine preferences for different double-blind methadone dose increases in 5 male patients. Subjects chose between 50 mg vs. 50 mg, 60 mg, 75 mg and 100 mg of methadone. In the 50 mg vs. 50 mg condition, each alternative was selected equally often. Percent selection of the higher doses (60, 75 and 100 mg) over the 50 mg dose of methadone increased in a dose-related fashion. Subject self-reports were consistent with methadone's opiate-like properties with dose-related trends being noted in most scales (e.g. opiate effects, drug liking). Overall, the results show that a choice procedure can be used successfully to assess the reinforcing properties of drugs in methadone maintenance patients and that methadone dose increases can function as a reinforcer in this population even under blind dosing conditions.
Adult↗
Contingent methadone delivery: effects on illicit-opiate use.
This study examined the effects of contingent vs. non-contingent delivery of a methadone dose supplement on relapse to illicit opiate use in the context of a methadone outpatient detoxification program. Following a 3-week methadone stabilization period on 30 mg, patients (N = 39) were randomly assigned to a contingent, a non-contingent, or a control treatment group. All patients received identical gradual reductions in their assigned methadone dose. During the dose reduction period (weeks 4-11), members of the contingent (N = 13) and non-contingent groups (N = 13) could obtain daily methadone-dose supplements up to 20 mg, but contingent group members could obtain supplements only if their most recent urinalysis results were opiate negative. Control subjects (N = 13) did not have dose increases available. The contingent group presented significantly lower opiate-positive urines during weeks 8-11 (14% positive) of the detox than the non-contingent (38% positive) or control (50% positive) groups. Additionally, the availability of extra methadone improved treatment retention and increased clinic attendance above levels observed in the control group. The potential for further use of methadone's reinforcing properties in the treatment of opiate dependence is discussed.
Adult↗
Effect of methadone dose contingencies on urinalysis test results of polydrug-abusing methadone-maintenance patients.
Drug abuse outcomes were examined during 2 contingency management procedures in which the size of the methadone dose was determined by recent urinalysis test results. Twenty polydrug-abusing methadone-maintenance patients were exposed to one of two specific altered dose consequences: a positive incentive procedure in which dose could only increase above baseline levels as a result of drug-free urines and a negative incentive procedure in which dose could only decrease below original baseline levels as a result of drug-positive urines. About 13% of urinalysis test results were drug-free during a 10-week pre-study baseline period while about 40-50% of urines were drug-free for both treatment groups during an 18-week intervention period. About half of the subjects in each study condition showed marked improvement during the intervention, while the other half failed to improve their urine test results. Treatment failures in the dose decrease as compared with the dose increase condition were more likely to drop out of the study. The study showed that size of the methadone dose can be effectively used as a consequence to influence illicit drug use during treatment. The study suggests that positive reinforcement as compared with aversive control procedures can produce an equivalent number of successful cases while avoiding dropout among patients who fail to respond to treatment.
Adult↗
Contingent payment procedures for smoking reduction and cessation.
We assessed the ability of a combined contingent reinforcement and intensive monitoring procedure to promote and sustain temporary smoking cessation among 34 hired research volunteers, and the ability of a smoking reduction test to predict the subsequent initiation of abstinence. During the 5-day cutdown test, subjects were paid from $0 to $6 per day depending on the extent of reduction from baseline CO levels. During the abstinence test, breath samples were obtained three times daily and subjects were paid $4 for each CO reading less than or equal to 11 ppm. Sixty-eight percent of subjects initiated abstinence. Of the breath samples collected during the abstinence test (91% of scheduled samples), 96.5% were less than or equal to 11 ppm and 80.5% were less than or equal to 8 ppm. Subjects who earned more money during the cutdown test were more likely to abstain (r = -0.51, p less than .001). Contingent reinforcement and intensive monitoring procedures appear to have usefulness for analog studies of smoking reduction and cessation.
Adult↗
Naloxone-precipitated withdrawal in humans after acute morphine administration.
Explore the source record for details and available documents.
Dose-Response Relationship, Drug↗
Smoking topography and carbon monoxide levels in smokers.
Factors which effect the expired air carbon monoxide (CO) levels of smokers were examined in matched subject pairs who smoked an equal number of daytime cigarettes but had different CO levels (mean difference = 15.4 ppm). Measures of puff number, duration, and spacing, as well as the amount of CO increase per cigarette (CO boost), were assessed while subjects smoked a single cigarette in daily laboratory sessions. Subjects with relatively high CO levels had larger increases in CO after smoking a single cigarette than did individuals with low CO levels (p. less than .005) but did not differ on any other smoking topography measure. These data suggest that simple topography measures of puff number and duration may not contribute to between subject differences in tobacco smoke exposure, and that greater attention should be given to more refined measures such as puff volume and depth of inhalation. These data also suggest that the measurement of CO boost per cigarette may provide useful information regarding tobacco smoke intake.
Carbon Monoxide↗
Contingent reinforcement for reduced breath carbon monoxide levels: target-specific effects on cigarette smoking.
This study determined the effects on smoking behavior of providing contingent reinforcement for nonsmoking versus reduced smoking afternoon breath carbon monoxide (CO) target levels. Twenty-eight hired chronic smoker volunteers were randomly assigned to one of three experimental conditions during a 10-day intervention: (a) 8 ppm target CO, $5 per day incentive (n = 11); (b) 16 ppm target CO, $4 per day incentive (n = 8); or (c) 8 ppm target CO, no incentive (n = 9). Both payment groups showed significantly lower CO levels and greater amounts of daytime smoking reduction than the no-pay group. A specific effect of CO target was also seen; 45% of subjects in the 8 ppm group compared with 0% of subjects in the 16 ppm target and no-pay groups produced average afternoon CO levels of 8.5 ppm or lower during the intervention. Average levels of CO and smoking reduction did not differ for the two paid groups, however, because some subjects in the 8 ppm group failed to reduce CO sufficiently to contact the reinforcer. Contingent reinforcement based on expired air CO levels can exercise powerful and precise (target-specific) control over smoking behavior, but there may be individual differences in ability to meet reinforcement contingencies if difficult targets are introduced abruptly.
Adult↗
Effects of smoke deprivation interval on puff topography.
Our purpose in this series of three studies was to determine the effects of deprivation interval on smoking topography. In experiment 1, subjects were allowed to smoke ad libitum for 1 hour after 3, 30, and 300 minutes of tobacco smoke deprivation. An increased latency to the first cigarette developed after 3 minutes deprivation and an increase in the number of cigarettes smoked occurred after 300 minutes of deprivation. In experiment 2, puff number and spacing were held constant to determine if smokers would compensate for long deprivation intervals by more intense smoking, i.e., increased puff volume. Puff volumes and carbon monoxide (CO) boosts did not differ across smoking bouts preceded by either 30, 100, or 300 minutes of tobacco smoke deprivation. In experiment 3, average puff volumes and CO boosts were examined during smoking periods with short (3, 10, and 30 minutes) deprivation intervals. Subjects smoked less intensely (lower puff volumes and CO boosts) when smoking was spaced by 3 than by 30 minutes. We conclude that smokers do not increase puff volume after long deprivation intervals up to 300 minutes, but they may decrease puff volumes after short (3 minutes) deprivation intervals when puff number and spacing cannot be used as compensatory mechanisms.
Adult↗
Pupillary response to methadone challenge in heroin users.
The relationship between self-reported illicit heroin use and pupillary response to a low-dose methadone challenge was examined in 28 men beginning methadone therapy for opiate dependence. Pupil diameter was assessed before and 60, 90, and 120 minutes after a 20 mg methadone dose on day 1 of treatment. Self-reports of opiate drug effects were also taken at these times. There was a significant negative correlation (r = -0.53) between pupillary constriction 120 minutes after drug dosing and the average dollar value of subjects' reported heroin use per week. In other words, those who showed the least pupillary constriction generally reported the highest amount of illicit heroin use. Total years since first opiate use was also a significant predictor of pupillary response (r = -0.46). Self-reported amount of heroin use and years since first opiate use together accounted for 60% of the total variance in pupillary response to the challenge (Mult r = 0.77). Pupillary response to a low-dose methadone challenge appears to be a clinically practical and objective method for determining opiate tolerance levels in applicants for methadone therapy.
Adult↗
Behavior therapy in drug abuse treatment: review and evaluation.
The goal of drug abuse treatment is to decrease the dominance of drug-related behaviors while enhancing the dominance of alternative socially acceptable behaviors. The behavioral techniques of extinction, satiation, and punishment can be used to suppress undesirable behaviors, and reinforcement can be used to enhance desirable behaviors. Methadone maintenance offers unique advantages for treatment of opiate abuse since methadone satiates the drug abuser, thereby reducing the reinforcing efficacy of illicit opiate drugs, while also serving as a reinforcer whose delivery in the treatment setting can be used in contingent arrangements. Short-term efficacy has been demonstrated in studies that used contingent treatment termination or contingent dose decreases as punishing events and contingent dose increases or contingent take-home privileges as reinforcing events to promote reductions in drug use and cooperation with clinic rules. Systematic use of dose adjustments and take-home privileges may be a useful adjunct to methadone maintenance treatment, having a positive impact both on client outcomes and clinic operation. Rehabilitation efforts might also benefit if delivery of reinforcers available at the clinic is contingent upon participation in skills training and therapy programs or community activities outside the drug abuse clinic.
Behavior Therapy↗
Hydromorphone effects on human conversational speech.
The present study provides an objective assessment of the increased talkativeness associated with acute opiate drug administration. Speech of five methadone-maintenance subjects was recorded continuously for 1 h following the injection of 0, 10, 14, or 18 mg hydromorphone. Dose-related increases in subjects' speech were observed, while no systematic changes were seen in speech of an undrugged partner. Dose-related increases were also obtained on an adjective checklist measuring characteristic opiate signs and symptoms. The relationship between behavioral, subjective, and reinforcing drug effects is discussed.
Adult↗
Verbal responding under a fixed-interval schedule: effects of D-amphetamine.
The purpose of this study was to characterize the effects of d-amphetamine (5-30 mg) on rate and distribution of verbal responding which was maintained under a fixed-interval (FI) schedule of reinforcement. Hired volunteer subjects simultaneously wrote and spoke narrative monologues; points were delivered under a multiple 5 min fixed-interval 1 min time out schedule for closure of a voice operated relay (VOR). Under placebo control conditions, most subjects paused for 2-4 minutes following the 1 min time out then spoke and wrote during later portions of the interval. d-Amphetamine increased both the number of words written and seconds of VOR closure in a dose-related manner. In subjects who showed typical FI response patterning, the drug generally decreased the length of early interval pausing and increased low control amounts of verbal responding which occurred early in the interval proportionately more than higher amounts of verbal responding seen during later portions of the interval. These drug effects on response patterning were generally similar to those seen in infrahuman species responding under fixed-interval schedules of reinforcement.
Adult↗