Biomedical subjects

F G Moeller

Publications and source records attributed to F G Moeller.

At least 19 recordsLinked to original sources

PubMed2001

Fluoxetine treatment of cocaine-dependent patients with major depressive disorder.

Sixty-eight male and female individuals with both DSM-IV diagnoses of cocaine dependence and major depressive disorder were randomly assigned to one of two medication conditions (placebo vs. 40 mg per day) as part of a double-blind, placebo-controlled clinical efficacy trial of fluoxetine for the treatment of this dual diagnosis. During the 12-week outpatient treatment phase all participants also received individual cognitive-behavioral psychotherapy targeting both cocaine use and depression. Depressive symptoms remitted as a function of time in treatment, with no significant medication effects found. Fewer cocaine positive urines were found during the first 6 weeks of treatment in the placebo group compared with the 40-mg group. Cocaine use and depressive symptoms during treatment were significantly correlated. The findings fail to support the role of fluoxetine for treatment of cocaine use and depression in dually-diagnosed patients.

Adolescent↗

PubMed2001

Measurement of inter-episode impulsivity in bipolar disorder.

We carried out a preliminary investigation of impulsivity in patients with bipolar I disorder not meeting criteria for active episodes. Barratt Impulsiveness Scale (BIS-11) scores were significantly higher in bipolar disorder than in control subjects. Laboratory measurements of impulsivity correlated with a BIS-11 score or severity of manic symptoms. Impulsivity in bipolar disorder may have both stable and state-dependent aspects.

Adult↗

PubMed2001

Plasma GABA levels correlate with aggressiveness in relatives of patients with unipolar depressive disorder.

Plasma gamma-aminobutyric acid (GABA) levels are decreased in some patients with depression, mania and alcoholism. Medications which increase plasma GABA improve symptoms of mood disorders and can decrease aggression. We examined the relationship between plasma GABA and aggressiveness on the Buss-Durkee Hostility Inventory in 77 psychiatrically healthy adults. In subjects selected for having a first-degree relative with primary unipolar depressive disorder (FH+, n=33), plasma GABA was negatively correlated with aggressiveness (beta=-0.338, P=0.036), as was age (beta=-0.483, P=0.005). A relationship between plasma GABA levels and aggressiveness was not observed in subjects with no such family history (FH-, n=44). Moreover, FH+ subjects had significantly lower plasma GABA concentrations than FH- subjects. These data suggest that low GABA levels may correlate with some aspects of aggressiveness and may be genetically regulated.

Adult↗

PubMed2001

Endogenous plasma testosterone levels and commission errors in women: A preliminary report.

A correlation between elevated testosterone and aggressive behavior has been demonstrated in animals and to a lesser degree in humans, primarily in the context of dominance. Some aggression, namely non-premeditated aggression, is characterized by impaired impulse control. Real-world aggressive histories and self-reported impulsivity have correlated with commission errors (failures to withhold responses to nontarget stimuli) in versions of the continuous performance test (CPT). To begin exploring whether testosterone may play a role in aggression due more to a direct relationship with impaired impulse control, we related plasma total testosterone concentrations of 27 psychiatrically healthy women to commission errors in two variants of the CPT - with and without interstimulus distracters. Controlling for age and IQ, testosterone did not relate to rates of correct detections in either task, but correlated positively with commission errors in the distracter CPT variant. In light of the fact previous studies find commission errors on the CPT are associated with impulsivity, the results of this study support a positive relationship between testosterone and impulsivity.

Aggression↗

PubMed2001

The impact of impulsivity on cocaine use and retention in treatment.

To determine whether impulsivity was related to severity of drug use and treatment outcome, 50 cocaine dependent subjects underwent baseline measures of severity of current cocaine use and the Barratt Impulsiveness Scale (BIS-11). The hypothesis of the study was that there would be a significant correlation between impulsivity and cocaine use severity. As predicted, there was a significant correlation between BIS-11 total scores and self-reported average daily cocaine use as well as cocaine withdrawal symptoms. A subset of 35 patients underwent a 12-week double-blind placebo controlled trial of buspirone and group therapy. Subjects with high baseline impulsivity remained in the study a significantly shorter period than did subjects with lower baseline impulsivity. This study shows that impulsivity is a significant predictor of cocaine use and treatment retention, and suggests the need for targeting impulsivity in cocaine dependence treatment.

Adult↗

PubMed2001

Dextroamphetamine for cocaine-dependence treatment: a double-blind randomized clinical trial.

A properly implemented agonist treatment regimen should improve retention and reduce illicit drug use. Cocaine-dependent subjects (N = 128) were enrolled in a 12-week randomized, double-blind, placebo-controlled trial. In the multistage dosing design, subjects initially received placebo (PBO) or 15 to 30 mg of dextroamphetamine sulfate, sustained-release capsules. At week 5, the dose doubled to 30 mg or 60 mg for active groups. Subjects attended the clinic twice a week, provided urine samples, obtained medication, and had one behavioral therapy session a week. Retention was best for the 15- to 30-mg group, whereas the proportion of benzoylecgonine-positive urine screens was, from lowest to highest, 30 to 60 mg, 15 to 30 mg, and PBO at study end. Dosing must be refined. The results provide support for additional examination of the agonist model in psychostimulant-dependence treatment.

Adult↗

PubMed2001

Psychiatric aspects of impulsivity.

OBJECTIVE: The authors discuss the relationship of impulsivity to psychiatric disorders and present selected hypotheses regarding the reasons for these relationships. METHOD: Previous research has shown significantly higher levels of impulsivity among patients with conduct disorder, personality disorders, substance use disorders, and bipolar disorder, compared to other psychiatric patients or healthy comparison subjects. A literature review of the theoretical bases of the relationship between these disorders and impulsivity is presented. Measurements of impulsivity and treatment options are discussed in relation to the physiology of impulsivity and the disorders in which it is a prominent feature. RESULTS: Impulsivity, as defined on the basis of a biopsychosocial approach, is a key feature of several psychiatric disorders. Behavioral and pharmacological interventions that are effective for treating impulsivity should be incorporated into treatment plans for these disorders. CONCLUSIONS: The high comorbidity of impulsivity and selected psychiatric disorders, including personality disorders, substance use disorders, and bipolar disorder, is in a large part related to the association between impulsivity and the biological substrates of these disorders. Before treatment studies on impulsivity can move forward, measures of impulsivity that capture the core aspects of this behavior need to be refined and tested on the basis of an ideologically neutral model of impulsivity.

Antipsychotic Agents↗

PubMed2001

Antisocial personality disorder, alcohol, and aggression.

Epidemiologic studies and laboratory research consistently link alcohol use with aggression. Not all people, however, exhibit increased aggression under the influence of alcohol. Recent research suggests that people with antisocial personality disorder (ASPD) may be more prone to alcohol-related aggression than people without ASPD. As a group, people with ASPD have higher rates of alcohol dependence and more alcohol-related problems than people without ASPD. Likewise, in laboratory studies, people with ASPD show greater increases in aggressive behavior after consuming alcohol than people without ASPD. The association between ASPD and alcohol-related aggression may result from biological factors, such as ASPD-related impairments in the functions of certain brain chemicals (e.g., serotonin) or in the activities of higher reasoning, or "executive," brain regions. Alternatively, the association between ASPD and alcohol-related aggression may stem from some as yet undetermined factor(s) that increase the risk for aggression in general.

Aggression↗

PubMed2000

Low dose zolmitriptan as a 5-HT neuroendocrine challenge agent in humans.

The 5-HT1B/D agonist sumatriptan has been used in a number of studies as a neuroendocrine challenge agent. Whether its neuroendocrine effects are centrally mediated is unclear, however, since sumatriptan shows minimal penetration of the central nervous system. Zolmitriptan shows a greater penetration into the central nervous system than sumatriptan, and has recently been shown to be an effective challenge agent. In order to determine the neuroendocrine, temperature and side effects of a 2.5 mg oral dose of zolmitriptan, 17 healthy volunteers underwent a placebo controlled, repeated measures, double blind neuroendocrine challenge. Zolmitriptan or placebo were administered, and cortisol, growth hormone, prolactin, blood pressure and temperature, were measured over four hours after the dose of zolmitriptan. Zolmitriptan at this dose was well tolerated by all subjects, with minimal side effects and only minor effects on blood pressure. There was a significant increase in serum growth hormone after zolmitriptan compared to placebo, however there were no significant effects on cortisol, prolactin or oral temperature. The neuroendocrine effects of 2.5 mg of orally administered zolmitriptan are similar to previously reported effects of sumatriptan, with minimal side effects.

Adult↗

PubMed2000

Differential behavioral effects of plasma tryptophan depletion and loading in aggressive and nonaggressive men.

Preliminary findings indicate that men with high trait hostility may be prone to aggression increases following plasma tryptophan (Trp) depletion. We measured laboratory aggression in men selected for presence (n = 12) or absence (n = 12) of aggressive histories. Testing occurred before and after plasma Trp depletion, Trp loading, and under a food-restricted control condition. Subjects were provoked by subtractions of money, and aggression was measured as the responses the subject made to ostensibly subtract money from the instigator of the subtractions. When subjects were highly provoked, there was a significant Trp condition x aggression history interaction effect on aggressive responding. In particular, laboratory aggression in aggressive men was elevated under Trp-depleted conditions relative to Trp-loaded conditions, whereas the opposite occurred in nonaggressive men. Moreover, plasma total Trp levels after Trp loading were significantly higher in nonaggressive men, and plasma free (but not total) Trp levels after Trp loading correlated negatively with aggressive responses in the aggressive men. These data corroborate earlier findings that aggressive men may be more prone to aggression induced by reductions in plasma Trp.

Adolescent↗

PubMed2000

The Brief Psychiatric Rating Scale as an acute inpatient outcome measurement tool: a pilot study.

BACKGROUND: Recent guidelines for length of stay at psychiatric hospitals may have an unacceptable impact on patient outcome at discharge. A valid measurement tool is needed to evaluate significant patient change during brief hospitalization, typically 7 days, and to provide early prediction of unfavorable short-term outcome. This study examines the utility of the Brief Psychiatric Rating Scale (BPRS) as such a tool. METHOD: During a 2-month testing period, the BPRS was administered to 87 successive adults admitted to an acute general psychiatric inpatient unit at admission, 2 days, 7 days, and weekly thereafter until discharge. Total BPRS scores and 4 subscores were used in the data analysis, which included paired t tests and correlation analyses. RESULTS: Mean BPRS total scores demonstrate significant (p < .001) patient improvement at days 2, 7, and 14 of the hospital stay. Changes in subscores and their relationship to eventual outcome vary across diagnostic groups. CONCLUSION: The BPRS appears to be a useful inpatient outcome measure since it is capable of demonstrating significant change during brief stays of 1 week or less. Subscale scores may provide more specific prediction of change and may help clarify outcome in individual patients who show insignificant change by total score.

Adult↗

PubMed2000

Effects of moderate and high doses of alcohol on attention, impulsivity, discriminability, and response bias in immediate and delayed memory task performance.

BACKGROUND: Prior studies that examined the effects of alcohol on Continuous Performance Test (CPT) performance have resulted in inconsistent outcomes. Most studies that examined the effects of alcohol on concentrated attention tasks (like the CPT) found little effect of alcohol on performance measures, even when doses that exceeded 0.8 g/kg were used. One likely reason for these inconsistencies is the varying difficulty (and sensitivity) of the task used, and as a result, comparisons between studies are difficult. This study is one in a series that examines the effects of alcohol on attention by using a difficult version of the CPT (Immediate and Delayed Memory Task--IMT/DMT). Our purpose for these studies has been two-fold, examining the effects of alcohol (1) on concentrated attention (i.e., correct detections) and (2) on errors (i.e., commission errors) previously correlated with impulsive behaviors. The first is important because previous studies have shown little effect of alcohol on attention, and the second is important because commission errors have been related to impulsive behaviors. METHODS: In the IMT/DMT, participants respond to a briefly displayed number when it is identical to the one displayed before it. The procedure includes immediate and delayed conditions where successive stimuli to be matched are delayed by 0.5 sec or by 3.5 sec. The three stimulus types included target (identical match), catch (four of five digits match), and filler (no match) stimuli. Twenty subjects completed this task after consuming either a placebo drink or a drink that contained 0.5 g/kg or 1.0 g/kg of alcohol on different days. RESULTS: The main findings were that (1) alcohol decreased the percentage of correct identifications of target stimuli; (2) alcohol increased the percentage of commission errors in relation to the number of correct target responses; and (3) alcohol decreased discriminability whereas response bias became more conservative. CONCLUSIONS: These results clearly demonstrated a time-course effect of the 1.0 g/kg alcohol dose on attention, impulsivity, discrimination, and response criteria when a variety of dependent measures are used.

Adult↗

PubMed1999

Influence of trait hostility on tryptophan depletion-induced laboratory aggression.

Previous research has indicated that laboratory aggression in men increases after temporarily reducing the synthesis and neurotransmission of serotonin (5-HT) in the brain using the plasma L-tryptophan (Trp) depletion technique. Further research indicates that male subjects selected for high trait hostility are particularly prone to increased aggression following plasma Trp depletion. In a recent study of laboratory aggression in male control subjects, we demonstrated that laboratory aggression increased following ingestion of a Trp-depleting beverage, but not after ingestion of a Trp-containing beverage nor under food-restricted conditions. We report here that the increases in aggression under Trp-depleted conditions were specific to men who scored the highest on the Buss-Perry Aggression Questionnaire. These preliminary data support earlier findings that compared to non-hostile men, hostile men may be more prone to behavior change induced by the perturbation of the 5-HT neurotransmitter system.

Adolescent↗

PubMed1999

D-fenfluramine challenge in posttraumatic stress disorder.

BACKGROUND: Much progress has been made in understanding the role of catecholamines in the pathophysiology of posttraumatic stress disorder (PTSD). Recent research has broadened the scope of neuroregulation of PTSD to include serotonin. METHODS: We used the serotonin-releasing agent and reuptake inhibitor, d-fenfluramine, to assess the integrity of the serotonin-mediated prolactin release in 8 men with combat-induced PTSD and 8 healthy men. RESULTS: The veterans with PTSD had a significantly lower prolactin response to d-fenfluramine as compared to healthy control subjects. The prolactin response to d-fenfluramine was inversely correlated with the patient's level of PTSD symptomatology and measures of aggression. CONCLUSIONS: This study demonstrates a central serotonin dysfunction, as reflected in a lower prolactin response to d-fenfluramine, in patients with PTSD.

Analysis of Variance↗

PubMed1999

Laboratory measures of aggression and impulsivity in women with borderline personality disorder.

To characterize how severe negative affect in women is reflected in objective measures of aggression and impulsivity, the aggressive and impulsive behavior of 14 hospitalized women with borderline personality disorder (BPD) was compared with that of 17 controls. In an impulsivity task, subjects experienced two sets of 50 trials during which they could choose a smaller, immediate monetary reward or a larger but progressively delayed reward. In a separate task (PSAP), subjects earned monetary reinforcers with repeated button presses, and were provoked by the subtraction of money which was blamed on a fictitious other participant. Subjects could respond by ostensibly subtracting money from the fictitious subject (the aggressive response). While selection frequency of the short-delay responses was similar in patients and controls, BPD patients responded to avoid longer delay of reward across trials, and had higher Barratt Impulsiveness Scale total scores and attentional subscale scores. BPD patients responded to the money losses with roughly three times as many aggressive responses as controls and had higher Buss-Durkee Hostility Inventory (BDHI), Brown History of Violence, and Retrospective Overt Aggression Scale scores than controls. Aggressive responding rates correlated positively with BDHI scores. These results extend previous findings that negative affect in women is reflected in laboratory behavioral measures.

Adult↗

PubMed1999

Plasma L-tryptophan depletion and aggression.

There is a well-established relationship between aggression and lowered serotonin neuro-transmission. Recently developed methodologies for manipulating L-tryptophan levels (and brain serotonin) have been applied to human laboratory studies of aggression. Collectively, these studies provide further evidence for the serotonin-aggression relationship. Two important findings have been made recently: (1) subsets of individuals (e.g., persons self-rating high on aggressive or hostility scales) may differ in their susceptibility to aggression produced through plasma tryptophan depletion; and (2) alcohol in combination with L-tryptophan depletion has an additive effect on aggression. All previous studies have been conducted with men. Extending these studies to women appears to be the much-needed next step given that serotonergic levels appear to vary both as a function of the menstrual cycle phase and menstrual symptomatology.

Aggression↗

PubMed1999

The effects of tryptophan depletion and loading on laboratory aggression in men: time course and a food-restricted control.

Some studies have shown that sharp reduction of L-tryptophan (Trp) concentration in plasma results in increases in laboratory-measured aggression. Conversely, raising plasma Trp has blunted aggression. These effects are presumably due to impaired or enhanced serotonin synthesis and neurotransmission in the brain. In this study, the laboratory-measured aggressive behavior of eight men under both Trp depletion (T-) and Trp loading (T+) conditions was compared to their aggressive behavior under food-restricted control conditions (overnight fast without an amino acid beverage). Subjects were provoked by periodic subtraction of money which was attributed to a fictitious other participant, and aggression was defined as the number of retaliatory responses the subject made ostensibly to reduce the earnings of the (fictitious) other participant. Following ingestion of the T- beverage, aggressive responding was significantly elevated relative to the food-restricted control condition, and this increased aggressive behavior became more pronounced across behavioral testing sessions on a time-course which paralleled previously documented decreases in plasma Trp concentrations. In contrast, no changes were observed in aggressive responding under T+ conditions relative to food-restricted conditions. These within-subject behavioral changes under depleted plasma Trp conditions support earlier indications of a role of serotonin in regulating aggression.

Adult↗

PubMed1999

Prolactin response to buspirone was reduced in violent compared to nonviolent parolees.

A neuroendocrine challenge procedure was carried out in male and female parolees. The parolees were divided into violent and non-violent groups based upon their criminal history. Buspirone (0.4 mg/kg), a 5-HT1a agonist, was used as the challenge agent and plasma prolactin levels were determined. The violent parolees had a blunted prolactin response compared to the non-violent parolees. While reduced serotonergic activity may account for this difference, the pharmacology of buspirone and control of prolactin release suggest a role for dopamine. A reduced serotonergic response would be consistent with a large body of data linking reduced serotonin function and aggressive behavior. While the mechanism is not definite, these data clearly provide evidence for an altered and blunted biological response in parolees with a history of violence.

Adult↗