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Pilocytic astrocytoma: correlation between the initial imaging features and clinical aggressiveness.

OBJECTIVE: Astrocytomas are classified as either fibrillary or pilocytic on the basis of their histologic appearance. The imaging features of the fibrillary astrocytoma correlate closely with the tumor's clinical aggressiveness and are, therefore, useful in predicting prognosis. Correlation between the imaging features and the clinical aggressiveness of the pilocytic astrocytoma, however, is not well established. Accordingly, we compared the initial MR and CT appearances of the lesion with tumor aggressiveness as seen clinically to determine if a correlation exists. MATERIALS AND METHODS: We retrospectively evaluated the initial MR images or CT scans of 32 consecutive patients who had a histologic diagnosis of pilocytic astrocytoma. The lesions were evaluated with regard to location, size, calcification, morphology, and degree of contrast enhancement. These initial imaging features were correlated with the aggressiveness of the tumor as seen clinically. Tumors were classified as aggressive or nonaggressive on the basis of their clinical manifestations. Patients with clinically aggressive lesions had progressive symptoms and radiologic evidence of tumor progression or recurrence within an unusually short period. Patients with clinically nonaggressive lesions had a more indolent course, either improving or remaining stable, on both clinical and radiologic evaluations. In 12 patients, the tumor was classified as aggressive clinically, either progressing or recurring within a median time of 7.5 months (range, 2.5-118 months) from the initial diagnosis. The remaining 20 patients had a clinically nonaggressive course. RESULTS: In our series of patients, lesion size and location were not significantly different between the nonaggressive and aggressive tumors, as noted clinically. Furthermore, the aggressive and nonaggressive tumors were similar with regard to the presence or absence of calcium. Most tumors in both groups showed either moderate or marked enhancement and were multilobular. CONCLUSION: The initial CT and MR features of pilocytic astrocytoma are unreliable for predicting which lesions will behave in a more aggressive manner clinically and have a poor prognosis.

Adolescent↗

Cooperative interactions of laminin 5 gamma2 chain, matrix metalloproteinase-2, and membrane type-1-matrix/metalloproteinase are required for mimicry of embryonic vasculogenesis by aggressive melanoma.

Vasculogenic mimicry describes a process where aggressive tumor cells in three-dimensional matrices mimic embryonic vasculogenesis by forming extracellular matrix (ECM)-rich, patterned tubular networks. Microarray gene chip analyses revealed significant increases in the expression of laminin 5 (Ln-5, gamma2 chain) and matrix metalloproteinases (MMP)-1, -2, -9, and MT1-MMP (MMP-14) in aggressive compared with poorly aggressive melanoma cells. These components colocalized with developing patterned networks and antisense oligonucleotides to the Ln-5 gamma2 chain (but not sense oligonucleotides), and antibodies to MMP-2 or MT1-MMP (but not MMP-9) inhibited the formation of these networks. Cultures which did not receive antibodies to either MMPs-2 or -14 contained the Ln-5 gamma2 chain promigratory cleavage fragments. Poorly aggressive melanoma cells seeded on collagen I matrices preconditioned by the aggressive cells formed tubular networks along the Ln-5 gamma2 chain-enriched tracks deposited by the aggressive cells. These results suggest that increased expression of MMP-2 and MT1-MMP, along with matrix deposition of the Ln-5 gamma2 chain and/or its cleavage fragments, are required for vasculogenic mimicry by aggressive melanoma cells. Furthermore, the apparent recapitulation of laminin-rich, patterned networks observed in aggressive melanoma patients' tissue sections by aggressive melanoma tumor cells in three-dimensional culture may also serve as a model to help identify specific molecular targets which could function as templates for the coordinated migration of aggressive tumor cells and their proteolytic remodeling of the ECM and may have profound implications for the development of novel therapies directed at the ECM to alter tumor progression.

Cell Adhesion Molecules↗

Juvenile maladaptive aggression: a review of prevention, treatment, and service configuration and a proposed research agenda.

OBJECTIVE: To review prevention programs, psychosocial and psychopharmacologic treatments, and service delivery configurations for children and adolescents with maladaptive aggression. To propose a research agenda for disorders of aggression in child and adolescent psychiatry. DATA SOURCES: Recent empirical studies were reviewed using searches of MEDLINE and PsycINFO (text terms: aggression, antisocial, violence, conduct, oppositional, psychosocial treatment, psychopharmacology, and prevention), relevant books, review articles, and bibliographies. DATA EXTRACTION: Articles met the following criteria: published in an English-language, peer-reviewed journal between 1980 and 2005, included a focus on individuals < 18 years old, and included an outcome measure of relevant significance. STUDY SELECTION: Results of 154 randomized, controlled psychosocial treatment trials, 20 controlled psychopharmacology studies, 4 open-label medication studies, and 2 psychopharmacology meta-analyses were reviewed. RESULTS: Prevention programs show promise for reducing future aggression in at-risk populations. Empirical support is available for the effectiveness of multifocused psychosocial treatments in reducing aggression in children and adolescents. Atypical antipsychotics, lithium, divalproex sodium, and stimulants for conduct problems associated with attention-deficit/hyperactivity disorder have empirical support for reducing aggression in selected patient populations. CONCLUSIONS: Therapeutic nihilism in the treatment of aggressive children and adolescents with conduct problems is no longer warranted. Multifocused psychosocial interventions given early in life to at-risk children have the most support for effectiveness. However, treatments for children who routinely present to the child psychiatrist with already well-established disorders of aggression are neither robust nor well-established. Further research into maladaptive aggression in referred children and adolescents within and across psychiatric diagnoses is important for the field of child and adolescent psychiatry.

Adolescent↗

Impulsive aggression in personality disorder correlates with tritiated paroxetine binding in the platelet.

BACKGROUND: To examine the relationship between binding parameters of the platelet central serotonergic (5-HT) transporter and measures of aggression and impulsivity in adult human subjects. METHODS: Maximal number of platelet tritiated paroxetine binding sites (Bmax) and dissociation constant (Kd) values were measured in patients with personality disorder (n = 24) and healthy volunteers (n = 12). Measures of aggression and impulsivity included the total score and aggression subscale of the Life History of Aggression, the Motor Aggression factor and the assault subscale of the Buss-Durkee Hostility Inventory, and the total score and motor impulsivity subscale of the Barratt Impulsiveness Scale. RESULTS: The Bmax, but not Kd, values of platelet tritiated paroxetine binding was inversely correlated with the Life History of Aggression total score and aggression score and with the Buss-Durkee Hostility Inventory assault score in patients with personality disorder but not in healthy volunteer subjects. This relationship was independent of influences of factors related to depression, global function, or history of alcoholism or drug abuse. CONCLUSIONS: Reduced numbers of platelet 5-HT transporter sites may covary with life history of aggressive behavior in patients with personality disorder. This may represent another abnormality in 5-HT function in individuals with personality disorder and aggressive behavior.

Adult↗

A double-blind placebo-controlled study of lithium in hospitalized aggressive children and adolescents with conduct disorder.

BACKGROUND: A subgroup of children and adolescents with conduct disorder are characterized by severe and persistent aggression. Although there is no agreed on treatment for such aggression, lithium carbonate has shown promise in some studies involving children. Our study was designed to critically assess the efficacy of lithium in the treatment of aggression in children and adolescents using a measure specific for aggression. METHODS: Subjects were inpatients with conduct disorder hospitalized because of severe and chronic aggression. A parallel-groups design was used in this double-blind, placebo-controlled trial with randomization to lithium or placebo. Only those who met the aggression criterion during the 2-week placebo-baseline period were randomized to 4 weeks of treatment. Outcome measures included Clinical Global Impressions, the Global Clinical Judgements (Consensus) Scale, and the Overt Aggression Scale. RESULTS: Eighty-six inpatients enrolled in the study; 40 (33 male and 7 female; median age, 12.5 years) entered and completed the treatment phase. Lithium was statistically and clinically superior to placebo. Sixteen of 20 subjects in the lithium group were responders on the Consensus ratings vs 6 of 20 in the placebo group (P=.004). Ratings on the Overt Aggression Scale decreased significantly for the lithium group vs the placebo group (P=.04). More than half of the subjects in the lithium group experienced nausea, vomiting, and urinary frequency. CONCLUSIONS: Lithium is a safe and effective short-term treatment for aggression in inpatients with conduct disorder, although its use is associated with adverse effects.

Adolescent↗

Parental and early childhood predictors of persistent physical aggression in boys from kindergarten to high school.

BACKGROUND: In a prior study, we identified 4 groups following distinct developmental courses, or trajectories, of physical aggression in 1037 boys from 6 to 15 years of age in a high-risk population sample from Montréal, Québec. Two were trajectories of high aggression, a persistently high group and a high but declining group. The other 2 trajectories were a low group and a moderate declining group. This study identified early predictors of physical aggression trajectories from ages 6 to 15 years. METHODS: In this study, logistic regression analysis was used to identify parental and child characteristics that distinguished trajectory group membership. RESULTS: For boys displaying high hyperactivity and high opposition in kindergarten, the odds of membership in the 2 high aggression groups were increased by factors of 3.0 (95% confidence interval [CI], 2.0-4.3) and 2.7 (95% CI, 1.9-3.8), respectively, compared with boys without these risks. Counterpart odds ratios for the risk factors of mothers' teen-onset of parenthood and low educational attainment were 1.6 (95% CI, 1.1-2.2) and 1.8 (95% CI, 1.3-2.4), respectively. Only the maternal characteristics distinguished between the trajectory of persistently physical high aggression and the trajectory starting high but subsequently declining. For the 2 maternal risk factors combined, the odds ratio of persisting in high level physical aggression was 9.4 (95% CI, 2.9-30.4). CONCLUSIONS: Kindergarten boys displaying high levels of opposition and hyperactivity are at high risk of persistent physical aggression. However, among kindergarten boys who display high levels of physical aggression, only mothers' low educational level and teenage onset of childbearing distinguish those who persist in high levels of physical aggression.

Adolescent↗

Physical provocation potentiates aggression in male rats receiving anabolic androgenic steroids.

Anabolic androgenic steroids (AAS) have been linked to indiscriminant and unprovoked aggression and violence. We employed a brief tail pinch to examine the effects of different AAS on intermale aggression in gonadally intact male rats in response to a mild physical provocation. Animals received 5 mg/kg testosterone propionate (TP), nandrolone (ND), or stanozolol (ST) 5 days/week. Controls received vehicle injections. After 12 weeks, rats were tested for aggression while treatments continued. Animals were paired with either gonadally intact or castrated opponents and were tested in the subject rat's home cage, the opponents's home cage, and a neutral cage. Aggression was tested during tail pinch of the subject rat and during tail pinch of the opponent rat. In TP-treated males, tail pinch significantly enhanced aggression in all social and environmental conditions compared to intact controls. TP treatment also significantly enhanced aggression when the opponents were tail pinched. Tail pinch did not increase aggression in ND-treated males, and aggression was significantly lower than controls in ST-treated males. As expected, cell nuclear androgen receptor binding was significantly elevated by the high dose of TP. Our results show that while AAS alone does not induce the indiscriminate and unprovoked aggression characteristic of 'roid rage, TP heightens the animals sensitivity to

Aggression↗

Short days and exogenous melatonin increase aggression of male Syrian hamsters (Mesocricetus auratus).

Many nontropical rodent species rely on photoperiod as a primary cue to coordinate seasonally appropriate changes in physiology and behavior. Among these changes, some species of rodents demonstrate increased aggression in short, "winter-like" compared with long "summer-like" day lengths. The precise neuroendocrine mechanisms mediating changes in aggression, however, remain largely unknown. The goal of the present study was to examine the effects of photoperiod and exogenous melatonin on resident-intruder aggression in male Syrian hamsters (Mesocricetus auratus). In Experiment 1, male Syrian hamsters were housed in long (LD 14:10) or short (LD 10:14) days for 10 weeks. In Experiment 2, hamsters were housed in long days and half of the animals were given daily subcutaneous melatonin injections (15 microg/day in 0.1 ml saline) 2 h before lights out for 10 consecutive days to simulate a short-day pattern of melatonin secretion, while the remaining animals received injections of the vehicle alone. Animals in both experiments were then tested using a resident-intruder model of aggression and the number of attacks, duration of attacks, and latency to initial attack were recorded. In Experiment 1, short-day hamsters underwent gonadal regression and displayed increased aggression compared with long-day animals. In Experiment 2, melatonin treatment also increased aggression compared with control hamsters without affecting circulating testosterone. Collectively, the results of the present study demonstrate that exposure to short days or short day-like patterns of melatonin increase aggression in male Syrian hamsters. In addition, these results suggest that photoperiodic changes in aggression provide an important, ecologically relevant model with which to study the neuroendocrine mechanisms underlying aggression in rodents.

Aggression↗

Emerging themes in preclinical research on alcohol and aggression.

Animal research into the alcohol-aggression relationship is based on a need to understand this relationship in people, and its success depends on the degree to which animal models can provide appropriate parallels to relevant human phenomena. Comparisons of human and animal literature suggest that parallels may be found for the following: alcohol enhances aggression in some, but not all individuals; consumption increases the probability of victimization (being attacked by a conspecific); alcohol reduces anxiety, and socially stressed individuals show increased voluntary consumption; alcohol reduces avoidance of threatening situations or stimuli and may place individuals at greater risk of being attacked; both anxiety reduction and decreased avoidance of threat may increase the probability of involvement in violent situations. These findings suggest that a variety of mechanisms may be involved in alcohol enhancement of aggression. Differences in effects of alcohol on human, as opposed to animal, aggression may reflect specific human capabilities. Although high doses of alcohol consistently reduce aggression in laboratory animals, this may reflect motoric and sedative effects that are not relevant for human behavior, in which verbal aggression and aggression involving the use of weapons make motor capability less important. Human voluntary alcohol consumption may also reflect response to stressors that also simultaneously promote aggression, a situation not paralleled by animal studies in which the drug is administered rather than voluntarily consumed. Nonetheless, obtained parallels suggest that animal experimentation using ecologically relevant situations can provide highly generalizable analyses of the alcohol-aggression relationship.

Aggression↗

Role of N-methyl-D-aspartic acid and cholecystokinin receptors in apomorphine-induced aggressive behaviour in rats.

We studied the aggressive behaviour induced by repeated treatment with apomorphine, a dopamine agonist (0.5 mg/kg s.c. twice daily, 10 days), in rats. The first signs of defensive aggressiveness appeared on the third day of apomorphine treatment and were generally seen on the 7th day. Aggressiveness induced by a challenge dose of apomorphine (0.5 mg/kg s.c.) on the 11th day was antagonized by haloperidol (0.05 and 0.1 mg/kg i.p.) and clozapine (10 mg/kg i.p.). An antagonist of N-methyl-D-aspartate (NMDA)-gated channels, dizocilpine (MK-801), also blocked the aggressive behaviour at 0.25 and 0.5 mg/kg i.p. but caused ataxia. When dizocilpine (0.25 mg/kg i.p.) and apomorphine were coadministered for 10 days, aggressive behaviour did not develop. At 0.025 mg/kg i.p., dizocilpine even accelerated the appearance of apomorphine-induced aggressive behaviour, which manifested on the 3rd day in all rats. In a separate study, a 7-day treatment with dizocilpine (0.25-1 mg/kg i.p.) of rats, sensitized by a prior 10-day apomorphine treatment, did not reverse the established aggressive behaviour. The coadministration of apomorphine and cholecystokinin (CCK) -A or -B antagonists, devazepide or L-365,260 (0.01-2.5 mg/kg i.p.) respectively, neither affected development of apomorphine-induced aggressive behaviour nor intensity of aggressiveness in the sensitized rats. In binding studies neither density nor affinity of striatal dopamine D2 receptors was changed by acute or chronic apomorphine treatment. The number of [3H]pCCK-8 binding sites in the frontal cortex increased already after a single injection of apomorphine.(ABSTRACT TRUNCATED AT 250 WORDS)

Aggression↗

Overt and fantasized aggression toward parents by enuretic and nonenuretic children.

This study compared the amount and direction of overt and fantasized aggression of enuretic and nonenuretic children. Following the dynamic approach, it was hypothesized that enuretic children would differ from nonenuretics in having more difficulty in expressing overt aggression toward their mothers than toward a neutral figure. In fantasy, enuretic children were expected to express more aggression feelings toward their parents than control subjects. Twenty-eight enuretic subjects and a matched group of control subjects were induced to aggress toward their mothers and toward a neutral figure. The experimental situation was a variation of the Buss (1961) technique for eliciting and measuring aggression. Aggressive fantasies were assessed, using Bene and Anthony's Family Relation Test (1957). A significant interaction was obtained between enuresis/nonenuresis and target figures. Enuretic subjects expressed more aggression toward a neutral figure than toward the mother (p = .05) and differed from the control group in expressing less aggression toward the mother (p = .10). On the fantasy level, a significantly opposite trend to the predicted one emerged: Enuretic subjects showed less aggression toward both parents. The results were discussed with respect to the dynamic and the behavioristic approach to enuresis, and further research directions were suggested.

Aggression↗

Evaluative factors in social problem solving by aggressive boys.

Components of social problem solving (problem definition, generation and prioritization of solutions, and generation and evaluation of consequences) were assessed in high aggressive and low aggressive boys from grades 2-3 and 5-6. When compared with their low aggressive peers, high aggressive boys at both grade levels were more likely to (1) define social problems based on the perception that others were hostilely-motivated adversaries, (2) generate few consequences for exhibiting aggression, (3) choose a "second-best" solution that was rated as ineffective, and (4) evaluate their own affective reactions to self-generated consequences of aggression as "wouldn't care" or as not "unhappy." In addition, within the group of aggressive boys, problem definition was found to be significantly related to both number of solutions generated and effectiveness of solutions that subjects chose as best and second-best. These findings are discussed in terms of early patterns of cognitive mediation that differentiate high aggressive children from their low aggressive peers.

Affect↗

The course of aggression in first-grade children with and without comorbid anxious symptoms.

We studied the course of aggressive behavior in an epidemiologically defined sample of first graders with and without comorbid anxious symptoms. Our primary purpose in doing so was to understand whether the stability of aggression in young children was attenuated or strengthened in the presence of comorbid anxiety. Previous studies of older children and adolescents had produced equivocal findings in this regard. Data on anxious symptoms were obtained through an interview of the children, whereas aggressive behavior was assessed through the use of a teacher interview and peer nominations. Assessments were performed in the fall and spring of first grade. In contrast to children classified as aggressive alone in the fall of first grade, boys and girls classified as aggressive and anxious in the fall of first grade were significantly more likely to be classified as aggressive in the spring in terms of teacher ratings and/or peer nominations of aggression. Thus our findings suggest that the link between early and later aggression may be strengthened in the presence of comorbid anxious symptoms, rather than attenuated. Future studies are needed to identify the mechanisms by which the course of aggression is influenced by the presence of comorbid anxiety.

Aggression↗

The development of aggression in toddlers: a study of low-income families.

The effort by developmental psychopathologists to understand the etiology of antisocial behavior has resulted in several significant findings. First, aggressive behavior is highly stable from early childhood into adolescence and adulthood. Second, parental factors including rearing practices and parental psychopathology, are correlated with childhood behavior problems. It was the aim of the present study to examine the correlates and stability of aggressive behavior in a sample of toddlers from low income families. Eight-nine mother-child dyads (52 boys and 37 girls) were observed in laboratory assessments when the child was 18- and 24-months old. Frequency and pervasiveness of aggression were coded from videotapes. Familial criminality, maternal depressive symptomatology, child noncompliance, and difficult child temperament were examined as contributors to the prediction of aggression in toddlers. Stability of aggression was moderate, especially for aggression occurring in low-stress situations. While there were few sex differences in the frequency and stability of aggression, there were marked differences in the correlates and predictors of aggression. Gender-specific, interactional models of the development of aggression are proposed.

Aggression↗

Selective breeding for isolation-induced intermale aggression in mice: associated responses and environmental influences.

Aggressive (TA) and nonaggressive (TNA) lines of mice were established by selective breeding for isolation-induced intermale aggression. This paper summarizes and updates studies performed on the TA and TNA lines. The genetic analysis revealed that in these lines the genes for aggression are located on the autosomes and demonstrate a Mendelian segregation. The genes are expressed only in the presence of androgens which are normally present only in males. Behavioral and biological responses associated with high and low levels of aggression in TA and TNA mice are reviewed. Line differences have been found in olfactory communication and marking behavior, in maternal and predatory aggression in females, in locomotor activity, and in learning abilities. Also, correlated neurochemical and endocrinological responses to the selection have been detected. Maternal factors during the preweaning period do not significantly affect the development of aggression in TA and TNA males, while early postweaning exposure to aggression or sex enhanced later aggressive and sexual activity. Early experience and genetic disposition for aggression are correlated, with TA males showing the greatest increase in the behaviors studied.

Aggression↗

A neurophysiologic model for aggressive behavior in the cat.

A neurophysiologic model for aggressive behavior in the cat is proposed. Stimulus-bound and seizure-bound aggression was evaluated in relation to limbic and basal ganglia induced seizures (after-discharges). Electrically induced limbic and basal ganglia after-discharges were used because they are known to implicate septohypothalamic sites from which aggression can be elicited by direct stimulation. The occurrence of behavioral aggression is correlated with the discharge characteristics of a single discharging system and with two interacting discharging systems. Aggression is composed of autonomic and somato-motor components which poses relatively low and high thresholds, respectively, for their activation. Aggression occurring during a combined septum and amygdala discharge was more intense and prolonged than with a septum discharge alone. Participation of a slow frequency discharging basal ganglia system activated seizure-bound aggression in an otherwise nonaggressive limbic seizure. The limbic and basal ganglia stimulations and after-discharges lowered the excitability threshold of the aggression system and made it more vulnerable to being activated by external stimuli, such as visual and auditory stimuli. These observations are reminiscent of patients with aggressive behavior associated with psychomotor seizures.

Aggression↗

CSF 5-HIAA and aggression in female macaque monkeys: species and interindividual differences.

RATIONALE: While the relationship among CSF 5-HIAA, impulsivity, and aggression is well characterized in males, its investigation in females is limited, and no studies have assessed its generalizability across primates by making simultaneous comparisons between and within closely-related species. OBJECTIVES: We tested three hypotheses. First, that female rhesus macaques would have lower CSF 5-HIAA concentrations and be more aggressive than would female pigtailed macaques. Second, that females of both macaque species would exhibit an inverse relationship between interindividual differences in CSF 5-HIAA concentrations and rates of severe aggression. Third, that subjects with high CSF 5-HIAA concentrations would be higher in social dominance within their respective groups than would subjects with low CSF 5-HIAA concentrations. METHODS: We obtained CSF samples from 61 individually housed female primates of two closely related species: rhesus macaques (Macaca mulatta) and pigtailed macaques (Macaca nemestrina). We later placed subjects in unisex social groups, and correlated interindividual differences in CSF 5-HIAA with aggression, wounding, and acquisition of social dominance rank. RESULTS: Between-species analyses indicated higher CSF 5-HIAA concentrations in pigtailed macaques, and higher rates of high-intensity aggression, escalated aggression, and wounds requiring medical treatment in rhesus macaques. Within-species analyses indicated that interindividual differences in CSF 5-HIAA concentrations were inversely correlated with escalated aggression and positively correlated with social dominance rank. CONCLUSIONS: These findings show that agonistic and social differences between closely-related species are correlated with CNS serotonin activity, as species that show relatively high rates of severe aggression also tend to have low concentrations of CSF 5-HIAA. We conclude that serotonergic functioning plays an important role in controlling impulses that regulate severe aggression and social dominance relationships in both male and female primates, and that between-species differences in agonistic temperament can be predicted by species typical CNS serotonin functioning.

Aggression↗

Relationship of disinhibition and aggression to blunted prolactin response to meta-chlorophenylpiperazine in cocaine-dependent patients.

RATIONALE: Considerable evidence indicates that serotonergic (5-HT) mechanisms may mediate central effects of cocaine, and disinhibition and aggression. OBJECTIVE: We investigated whether prolactin (PRL) response to meta-chlorophenylpiperazine (m-CPP), a mixed 5-HT agonist/antagonist, differed between abstinent cocaine-dependent patients and controls and whether m-CPP challenge responses were related to measures of disinhibition and aggression. METHODS: Thirty-five cocaine-dependent African-American subjects who were abstinent for at least 2 weeks and 33 African-American controls underwent assessments of disinhibition and aggression and a challenge with 0.5 mg/kg of oral m-CPP. RESULTS: The PRL response to m-CPP was compared between cocaine patients and controls and between subgroups categorized high or low based on disinhibition and aggression measures. Hierarchical regressions were used to determine whether behavioral measures predicted deltaPRL (peak PRL-baseline PRL). The PRL response to m-CPP was significantly diminished in cocaine patients compared to controls. The blunting was more robust in cocaine patients with high disinhibition and aggression. Among cocaine patients, the high-disinhibition subgroup showed greater blunting than the low-disinhibition subgroup and there was a trend for the high-aggression subgroup to be more blunted than the low-aggression subgroup. The subgroups of controls did not differ from each other. A combination of disinhibition and aggression measures significantly predicted deltaPRL in cocaine patients. CONCLUSION: The results indicate that cocaine-dependent patients show disturbances in postsynaptic 5-HT function during early abstinence. It appears that the 5-HT disturbances are more pronounced in the subgroup of cocaine patients with high disinhibition and aggression.

Adult↗