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M Vogel-Sprott

Publications and source records attributed to M Vogel-Sprott.

At least 19 recordsLinked to original sources
PubMed2005

Alcohol, intentional control, and inappropriate behavior: regulation by caffeine or an incentive.

This study shows that reduced intentional control under alcohol can be counteracted by caffeine or an environmental incentive. Four groups of social drinkers (n = 11) received 1 of the following: 0.62 g/kg alcohol (A), alcohol with 4.4 mg/kg caffeine (AC), alcohol with a rewarding monetary incentive (AR), or a placebo (P). They then performed a word stem completion task that provided separate measures of the influence of controlled and automatic processes governing responses. Controlled processes were depressed in Group A compared with Group P, whereas Groups AR and AC did not differ from Group P. Most inappropriate responses were displayed under alcohol alone, fewer with caffeine, and least with incentive. No treatment significantly affected automatic processes.

Adult↗
PubMed2004

The stage-specific effect of alcohol on human information processing.

RATIONALE: Research on the limits of information processing shows that when a dual task is performed in quick succession, performance on the second task is increasingly degraded as the temporal gap between task 1 and task 2 decreases. The carry-over effect on task 2 is assumed to occur because the central cognitive stage of processing must be completed before the processing of task 2 can begin. This creates a bottleneck when the tasks are performed in close succession, but with longer delays task 2 is no longer affected by task 1. OBJECTIVES: It was predicted that if alcohol disturbs (slows) the central stage of processing, shorter delays between task 1 and task 2 should reveal more intense disruption in the performance of task 2. METHODS: Two groups (n=16) of healthy male social drinkers performed a baseline test on a dual task. On each trial, task 1 was followed by task 2 at one of four delays (50, 200, 500, and 1100 ms). The groups then received either 0.65 g alcohol/kg or a placebo and performed the task again. RESULTS: The RT of the alcohol and placebo groups did not differ on the baseline test. In accord with the hypothesis, the alcohol group performed task 2 more slowly on the treatment test than did the placebo group at the three shortest delays (P<0.02). At the longest delay, the RT of the groups did not differ (P>0.15). CONCLUSIONS: This pattern of task 2 RTs indicates that a moderate dose of alcohol can significantly impair (slow) the central, cognitive stage of information processing.

Adult↗
PubMed2004

Fast, but error-prone, responses during acute alcohol intoxication: effects of stimulus-response mapping complexity.

BACKGROUND: Although moderate doses of alcohol can impair performance on tasks that require information processing, little is known about the locus of the alcohol effects within the processing stream. This study used a psychological refractory period paradigm to investigate the effect of alcohol on the central, cognitive stage of information processing when task complexity is manipulated by altering stimulus-response compatibility. METHODS: Thirty-four healthy male social drinkers were assigned to one of two groups (n = 17) that performed two tasks. Each trial consisted of a task 1 stimulus (tone) followed by a task 2 stimulus (letter) that was presented after one of four stimulus onset asynchronies (50, 200, 500, or 1100 msec). A baseline test of performance was obtained before the groups received a beverage containing either 0.0 g/kg (placebo) or 0.65 g/kg alcohol. Both groups were retested when blood alcohol concentration (BAC) was increasing and was decreasing. RESULTS: The alcohol group made significantly more errors in task 1 compared with their drug-free baseline measure during the ascending phase of the BAC curve, and error rates increased to a greater extent for the more complex arbitrary stimulus-response mapping condition. Moreover, this increase in errors continued unabated during the descending phase of the BAC curve. Increasing BACs also slowed performance (longer reaction time), but unlike errors, reaction time returned to drug-free baseline levels when BAC was decreasing. CONCLUSIONS: The results provide evidence that an acute dose of alcohol can impair one aspect of the central, cognitive stages of information processing. The possibility that errors in information processing remain during decreasing BACs even after processing speed has returned to drug-free levels has important practical implications relating to the detrimental consequences of acute alcohol intoxication.

Adult↗
PubMed2001

Alcohol and behavioral control: cognitive and neural mechanisms.

This article represents the proceedings of a symposium at the 2000 RSA Meeting in Denver, Colorado. The organizer/chair was Muriel Vogel-Sprott. The presentations were (1) Alcohol-induced impairment of inhibitory control: Some commonalities with attention deficit hyperactivity disorder, by Mark Fillmore; (2) Neural interactions that underlie response inhibition under alcohol: A functional magnetic resonance imaging investigation, by Craig Easdon; (3) Intentional control of behavior under alcohol, by Muriel Vogel-Sprott; and (4) Working memory and the disinhibiting effects of alcohol on passive avoidance learning, by Alicia Justius and Peter Finn.

Alcoholism↗
PubMed2001

Maintaining intentional control of behavior under alcohol.

BACKGROUND: This research used a process dissociation paradigm to measure the influence of controlled and automatic processes on a word-stem completion task when correct performance under alcohol was positively reinforced, or had no particular consequence. It was predicted that the impairing effect of alcohol on controlled processes that govern intentional control of behavior would be resisted when drinkers were reinforced for performing well. METHODS: Four groups of eight male drug-free social drinkers initially studied a list of words. Two of the groups then received 0.56 g/kg alcohol (A) and two received a placebo (P) before the stem-completion task was performed. During the task, the correct responses of one pair of A and P groups were reinforced (money and verbal approval) whereas no reinforcement was provided to the other pair. RESULTS: As predicted, under alcohol, the influence of controlled processes that govern intentional responses was greater when reinforcement was provided than when it was absent (p = 0.005). Without reinforcement, controlled processes in the A group were lower than the P control group (p = 0.01). In contrast, the A and P groups that received reinforcement did not differ (p = 0.142). Controlled processes in the P groups were not affected by reinforcement (p = 0.65). In addition, the influence of automatic processes was not affected by alcohol or by reinforcement (p > 0.781). CONCLUSIONS: Positive reinforcement for behavior under alcohol increases the influence of controlled processes. These results suggest that the degree to which intentional control is retained under alcohol depends on the consequence of behavior in the situation. It seems that controlled processes enable drinkers to intentionally display the behavior that is rewarded.

Adult↗
PubMed2000

Alcohol and behavioral control: impaired response inhibition and flexibility in social drinkers.

This study shows that a moderate dose of alcohol (0.62 g/kg) can impair cognitive processes controlling behavioral inhibition and flexibility (i.e., inhibiting one response and making a different one). Two groups of male social drinkers (n = 8) received alcohol or a placebo and performed two change tasks that required high or low information processing. Results showed that alcohol impaired inhibitory control and response flexibility following a failure to inhibit a first response, and the intensity of impairment did not differ under the two information processing conditions. Response reaction time and accuracy were not affected by alcohol. These findings indicate that alcohol can impair some cognitive aspects of behavioral control before basic motor processes are affected.

Adult↗
PubMed2000

Response inhibition under alcohol: effects of cognitive and motivational conflict.

OBJECTIVE: This experiment tested the effect of cognitive and motivational conflict on response inhibition under alcohol. METHOD: Fifty-six male social drinkers were randomly assigned to one of eight groups (n = 8). Four pairs of groups received 0.62 g/kg of alcohol, or a placebo, and each pair performed a go/stop choice reaction time task under one of four conflict conditions. One condition (C) produced cognitive conflict by presenting "go" and "stop" signals in the task. Another condition (IR) added motivational conflict by administering an equal monetary reward for inhibiting responses to stop-signals, and for responding to go-signals. The remaining two conditions resolved the motivational conflict by administering the monetary reward only for inhibitions (I), or only for responses (R). RESULTS: Compared with placebo, alcohol reduced inhibitions (i.e., impaired inhibitory control) under cognitive conflict (C; p = .041) and under motivational conflict (IR; p = .012). No significant effect of alcohol on inhibitions was observed in conditions where conflict was resolved (i.e., I and R). CONCLUSIONS: The study shows that alcohol can reduce the ability to inhibit a response. However, impaired inhibitory control is not an inevitable outcome of the drug action, because it can be counteracted by the consequences of behavior in the situation.

Adult↗
PubMed1999

An alcohol model of impaired inhibitory control and its treatment in humans.

This study developed a model of impaired inhibitory control in humans to test the efficacy of treatments for this deficit. Male social drinkers (N = 35) practiced a "go-stop" task that measured response inhibition. They then were assigned to 1 of 5 groups (n = 7) that performed the task under a different treatment. The model of impaired inhibitory control was provided by administering 0.62 g/kg alcohol to 1 group (A), whose response inhibition was compared with a placebo group (P). The other 3 groups received 0.62 g/kg alcohol plus a treatment designed to ameliorate alcohol impairment of inhibitory control: behavioral reinforcement (B), or 4.4 mg/kg caffeine (C), or a combination of both (B + C). Alcohol impaired inhibitory control, and all 3 treatments (B, C, and B + C) counteracted the impairment. The findings indicate that alcohol impairment of response inhibition may provide a useful human model to test conditions that may ameliorate or exacerbate deficits in behavioral control induced by drugs or other factors.

Adult↗
PubMed1999

Alcohol effects on intentional behavior: dissociating controlled and automatic influences.

This research examined the effect of alcohol on intentional behavior using a process dissociation procedure to separate the influences of conscious controlled processes from those of unconscious automatic processes. In 2 identical experiments, 24 male social drinkers studied a list of words before they received either 0.56 g/kg alcohol, an alcohol placebo, or soda. Participants then performed a word stem completion test that provided estimates of controlled influences and of automatic influences on their responses. The results of the 2 experiments were consistent. Comparisons among the treatments showed that alcohol reduced conscious controlled processes and left automatic processes unchanged. The findings contribute to understanding how the drug may reduce cognitive control of intentional behavior and raise important questions concerning personal and environmental factors that might mediate these effects.

Adult↗
PubMed1998

Alcohol, cognitive impairment and expectancies.

OBJECTIVE: This experiment tested the hypothesis that differences in subjects' expectations about the impairing effect of alcohol on cognitive performance predict their responses to alcohol and to a placebo. METHOD: Twenty-seven male social drinkers were randomly assigned to one of three treatment groups: alcohol (0.62 g/kg), placebo, or no treatment control. All groups practiced a Rapid Information Processing Task that measured cognitive performance by the speed of information processed. After practice, they rated the degree of impairment they expected alcohol to have on their performance, and then performed the task under their different treatments. RESULTS: Alcohol slowed (i.e., impaired) information processing compared with placebo and no treatment. In addition, those who expected more impairment performed more poorly under alcohol, and under the placebo when alcohol was expected. When no beverage was received, no expectancy-performance relationship was obtained. CONCLUSIONS: The findings call attention to expectancies as an important factor that may contribute to individual differences in cognitive functioning under alcohol and placebo.

Adult↗
PubMed1998

Behavioral impairment under alcohol: cognitive and pharmacokinetic factors.

This study tested the hypothesis that the intensity of behavioral impairment under alcohol is related to social drinkers' expectancies about impairment and their rates of rise in blood alcohol concentration (BAC). After subjects (n = 30) were trained on a psychomotor task, they rated the impairment they expected from alcohol and then performed the task under alcohol (0.56 g/kg) or a placebo. Alcohol impaired performance, compared with placebo. Drinkers' expectations about impairment and their rates of rise in BAC were independent, and each factor predicted a significant portion of the variance in alcohol impairment among drinkers. More intense impairment under alcohol was associated with expectations of greater impairment and with swifter rates of rise in BAC. BACs obtained by drinkers during task performance were not related to the intensity of impairment they displayed. The study shows that a pharmacological and nonpharmacological variable can each affect a drinker's behavioral impairment under alcohol, and this finding contributes to our understanding of conditions where BAC per se may be an unreliable indicator of impairment.

Adult↗
PubMed1997

Resistance to cognitive impairment under alcohol: the role of environmental consequences.

This study showed that cognitive impairment under alcohol is affected by environmental factors. Forty male social drinkers were randomly assigned to 4 groups. Participants practiced a task that measured their rate of information processing. Three groups then performed the task under a moderate dose of alcohol (0.62 g/kg) and received either an immediate, informative monetary consequence (MI); a delayed, uninformative monetary consequence (M); or no consequence (N) for maintaining their unimpaired processing rate. A control group (C) performed the task without alcohol or any consequence for performance. The processing rates of Groups M and N were slower (i.e., impaired) under alcohol than those of Group C. In contrast, Group MI displayed no significant reduction in processing rate under alcohol (i.e., no impairment). Resistance to the impairing effects of alcohol on information processing is enhanced by a rewarding consequence that conveys information about the adequacy of performance under the drug.

Adult↗
PubMed1997

Drunk or sober? Learned conformity to a behavioral standard.

OBJECTIVE: This research tested the hypothesis that behavioral standards in a drinking situation are learned. METHOD: Two groups of male social drinkers (N = 12) were reinforced with verbal feedback (FB) for matching either a "sober" (S) or an "intoxicated" (I) behavioral standard under repeated doses (0.62 g/kg) of alcohol. The criterion measure was time to perform a trial on a psychomotor tracking task. A fast, efficient time (115 seconds) defined the S standard. A slow, inefficient time (150 seconds) defined the I standard. The behavioral effect of standards was tested during a final FB training session under alcohol, and during retention under a placebo and under alcohol, with FB absent. RESULTS: S and I groups approximated their respective standards when reinforced, and these standards were retained when reinforcement was subsequently withheld. Under placebo, group S displayed sober performance comparable to their drug-free baseline, whereas Group I's performance was significantly impaired. These group differences remained significant under alcohol, and the drug effect impaired each group's performance to a similar degree. CONCLUSIONS: Prior reinforcement of a standard under alcohol can lead to the display of that standard when alcohol is expected or received. The consistent difference in the groups' performance under placebo and under alcohol suggests that learned standards may add an effect on behavior in a drinking situation that is distinct from the drug effect. Retention of group standards under alcohol in the absence of reinforcement confirms that these standards were learned and were not simply a response to situational demand.

Adult↗
PubMed1997

Alcohol and the ability to inhibit behavior in men and women.

OBJECTIVE: This experiment tested the impairing effect of alcohol on cognitive inhibitory control of behavior in the absence of any motivational consequences for exhibiting or inhibiting a response. METHOD: Men (n = 24) and women (n = 24) were trained on a computerized "go-stop" task that measured response reaction time (RT) to a go signal and inhibitory control by the number of inhibitions to a randomly occurring stop signal. Equal numbers of men (n = 8) and women (n = 8) were assigned to one of three groups (n = 16), and they performed the task alone in a room under either alcohol (A), placebo (P) or no-treatment control (C) conditions. Blood alcohol concentrations of men and women were matched in Group A by administering 0.62 and 0.54 g/kg of alcohol, respectively. RESULTS: Alcohol impaired inhibitory control and had no significant effect on response RT. Under P and C conditions, no changes in inhibitions or response RT were observed. In addition, no significant gender effects were found. CONCLUSIONS: The results showed that inhibitory control of behavior was impaired by a moderate dose of alcohol that did not affect response RT.

Adult↗
PubMed1997

Is behavioral tolerance learned?

Both scientific and anecdotal evidence indicates that social drinkers can develop resistance (i.e., behavioral tolerance) to alcohol's impairing effects over time. Although repeated exposure to alcohol is thought to explain tolerance development on a physiological level, the acquisition of behavioral tolerance appears to involve additional factors. In particular, learned associations between a drinker's behavior following alcohol consumption and the subsequent consequences may play an important role. When favorable consequences result from displaying unimpaired (i.e., tolerant) behavior after drinking, a drinker learns to develop behavioral strategies to compensate for alcohol's effects. In contrast, if a drinker does not receive a reward for unimpaired behavior--or finds that a more favorable outcome follows the display of intoxicated behavior--tolerance does not develop. Studies show that subjects also can develop behavioral tolerance to alcohol when they practice a task while impaired by factors other than alcohol or when they mentally rehearse task performance while under the influence of alcohol.

Alcohol Drinking↗
PubMed1996

Social drinking history, behavioral tolerance and the expectation of alcohol.

This research tested the hypothesis that a compensatory response to cues for alcohol contributes to the greater behavioral tolerance displayed by more experienced social drinkers. Sixty male social drinkers, ranging from 19 to 24 years of age, participated in the study. Thirty subjects had been drinking for 20 months or less (mean = 11.0 months), and were classified as novice (N) drinkers. The remaining 30 subjects had been drinking for 24 months or more (mean = 40.8 months), and were classified as experienced (E) drinkers. All subjects practiced a pursuit rotor task that measured psychomotor skill. Equal numbers of E and N subjects were then assigned to one of three groups (n = 10). Two groups were led to expect alcohol and performed the task after receiving either 0.56 g/kg alcohol, or a placebo. The third group received no beverage, E subjects displayed more behavioral tolerance to alcohol than did N drinkers. In accord with the hypothesis, E drinkers displayed a drug-opposite improvement in performance under a placebo, whereas N drinkers showed no appreciable change in performance. These observations support the hypothesis that the acquisition of a compensatory response to cues predicting the administration of alcohol contributes to the greater behavioral tolerance of more experienced drinkers.

Adult↗
PubMed1996

Drug-free behavioral history affects social drinkers' tolerance to a challenge dose of alcohol.

OBJECTIVE: This research tested the hypotheses that behavioral tolerance to a challenge dose of alcohol is enhanced by prior drug-free training under environmentally induced impairment and that the addition of verbal feedback about performance during training is ineffective. METHOD: A total of 44 male social drinkers participated in two studies that provided drug-free training of a psychomotor task (tracometer) under conditions of either moderate or intense environmental impairment. Impairment was produced and manipulated by the position of a screen that reduced the visibility of the task target display. Subjects were assigned to one of four groups in each study. Two experimental (E) groups received drug-free training under impairment, either with or without feedback, and two control (C) groups were trained either with or without feedback. After drug-free training, all subjects received a .62 g/kg dose of alcohol and performed the task. RESULTS: E groups displayed more resistance to the effect of alcohol than did C groups, and feedback had no significant effect. Training under moderate or intense environmental impairment diminished drug effects to such an extent that subjects' performance under alcohol did not differ from their drug-free baselines. CONCLUSIONS: Results show that a drug-free history of performance under environmental impairment can increase behavioral tolerance to a challenge dose of alcohol. The findings imply that an individual's drug-free behavioral history may contribute to differences in response to a challenge dose of alcohol.

Adult↗