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espanolEditorial del monografico Mindfulness y Psicoterapia 10 anos despues (2006-2016) EnglishFrom the Editor: Mindfulness and Psycotherapy 10 years later (2006-2016)

The aim of this randomized pilot study is to investigate the effects of a short training programme in loving-kindness and compassion meditation (LKM/CM) in patients with borderline personality disorder. Patients were allocated to LKM/CM or mindfulness continuation training (control group). Patients in the LKM/CM group showed greater changes in Acceptance compared with the control group. Remarkable changes in borderline symptomatology, self-criticism and self-kindness were also observed in the LKM/CM group. Mechanistic explanations and therapeutic implications of the findings are discussed. Highlights: Three weeks of loving-kindness and compassion meditations increased acceptance of the present-moment experience in patients with borderline personality disorder. Significant improvements in the severity of borderline symptoms, self-criticism, mindfulness, acceptance and self-kindness were observed after the LKM/CM intervention. LKM/CM is a promising complementary strategy for inclusion in mindfulness-based interventions and Dialectical Behavioural Therapy for treating core symptoms in borderline personality disorder. Copyright © 2016 John Wiley & Sons, Ltd.

En la actualidad asistimos a la introducción de las técnicas de mindfulness en la educación, la psicoterapia y en todo el ámbito científico en general. Una de las razones de este auge son los conocimientos proporcionados por las modernas técnicas de investigación neurobiológica. En este trabajo revisamos algunos de los efectos de mindfulness sobre los procesos perceptivos (apertura a la novedad), el estilo afectivo (afecto positivo y aproximación), la inmunidad (incremento) y la empatía (facilitación). Los hallazgos neurobiológicos sugieren que la práctica de mindfulness activa y fortalece diversas regiones cerebrales (especialmente la corteza prefrontal) encargadas de los procesos integradores más específicamente humanos, provocando cambios morfológicos duraderos de la corteza cerebral y en los hábitos mentales. Todos estos hallazgos enriquecen y confluyen en la Neurobiología Interpersonal que, al integrar conocimientos procedentes de campos muy diversos, se está revelando como una valiosa fuente de conocimientos para la práctica clínica de la psicoterapia.

The dopaminergic and opioid systems have effects on the conditioned avoidance response (CAR), although the possible interaction between these systems on this behaviour has not been studied. The effects of morphine (12.6 mg/kg), haloperidol (0.075 mg/kg), sulpiride (20 mg/kg) and risperidone (0.1 mg/kg) alone as well as morphine combined with these dopamine (DA) antagonists on the acquisition and performance of the CAR were explored in mice. Morphine increased avoidances but this seemed secondary to a rise in activity levels. All DA antagonists impaired CAR in the acquisition phase but only haloperidol disrupted performance. The combination of morphine plus neuroleptics impaired acquisition and performance of CAR. These results suggest that morphine disrupts the learning of CAR and that the classical neuroleptic haloperidol profoundly impairs acquisition and performance of CAR to a greater degree than atypical neuroleptics such as sulpiride and risperidone. Finally, it is concluded that morphine potentiates the impairing effects of DA antagonists on CAR.

The aim of this work was to test the antiaggressive effects of lorazepam and to determine whether these effects were mediated by benzodiazepine receptors. In a first experiment, male mice were injected with lorazepam in a range of low doses (0.05, 0.1, 0.2, and 0.6 mg/kg) or saline solution. In a second experiment, 1 mg/kg of Ro 15-1788, a benzodiazepine receptor antagonist, and a saline solution were injected before the behavioral test. Results showed that 0.6 mg/kg of lorazepam was the only dose that decreased the total duration of threat ( P < .01) and social investigation ( P < .05) and that 1 mg/kg of Ro 15-1788 had no effects. In the third experiment, animals received two injec- tions: 0.6 mg/kg of lorazepam plus 1 mg/kg of Ro 15-1788, 0.6 mg/kg of lorazepam plus saline solution, or saline solution plus saline solution. Those treated with lorazepam and saline solution spent less time digging (P < .001), threatening (P < .001), and attacking (P < .05) and more time avoiding the opponent (P < .01) or being immobile (P < .001) than the controls. Ro 15-1788 was successful in completely antagonizing the behavior modulated by lorazepam. Aggr. Behav. 28:248- 256, 2002. © 2002 Wiley-Liss, Inc.

Many reports have demonstrated that there is a development of tolerance to many effects produced by morphine. This study was conducted with the aim of determining whether the antiaggressive actions of morphine develop tolerance after chronic administration. Acute morphine administration produced antiaggressive effects which disappeared after chronic (7 days) treatment in isolated mice. An increase in non-social exploration was observed, representing morphine-induced hyperactivity, after acute treatment, which was not present after chronic administration. In conclusion, there is a development of tolerance to the antiaggressive and motor effects of morphine. Language: en

Distinguishing the specific effects of neuroleptics on one particular behaviour from its non-specific effects on motility is not easy. In this study, the effects of five neuroleptics on spontaneous motor activity were compared and the ED(50) values of these drugs to impair activity were calculated. Male and female mice were evaluated in an actimeter or in a shuttle-box used as an open field after the administration of chlorpromazine (0.4, 1.2, 3.6 mg/kg), haloperidol (0.1, 0.3, 0.9 mg/kg), raclopride (0.1, 0.3, 0.9 mg/kg), sulpiride (10, 30, 90 mg/kg) and clozapine (0.4, 1.2, 3.6 mg/kg), and two automatic and two observational activity measures were obtained. A very high correlation between automatic and observational measures, absence of sex differences, and a dose-dependent decrease of activity were observed with every compound. The results allow us to make accurate comparisons between these drugs in their potency in reducing spontaneous motor activity.

The role of hormones in human aggression is open to debate, but takes on a new urgency owing to the alarming abuse of androgenic anabolic steroids by some sports participants. In this study, video-taped behavior exhibited by 28 male competitors during a judo fight was assessed to analyze its relation to serum testosterone and cortisol levels measured before and after the bouts. A positive relation between testosterone and offensive behaviors was obtained in the sense that the greater the hormonal titer, the greater the number of threats, fights, and attacks. These findings coincide with the pattern of relationships found using observational scales. Conversely, cortisol also presented positive correlations with some of these behavioral categories but did not moderate the relationship between testosterone and competitive behavior. The present results corroborate and extend earlier findings on the role of these hormones in human behavior, giving support to the view that testosterone can be linked to the expression of competitive aggression.

Insufficient research has been carried out on the effects of repeated treatments with psychostimulants on agonistic behaviour. These effects were studied in mice using different schedules of administration and employing a low dose of amphetamine (1.5 mg/kg) which did not produce significant motor disruptions. After two injections, with a 5-day interval between them, antiaggressive effects (decreases in attack and increases in avoidance/flight behaviour) were found, which were similar to those observed after acute administration, in addition to an increase in defence. With a higher number of injections but with shorter intervals (daily treatment) the effects diminished and even disappeared. Tolerance to the antiaggressive as well as to motor effects (digging and non-social exploration) was found after 7 daily injections. The appearance of avoidance, defensive and flight behaviours in this model supports the inclusion of agonistic behaviour in rodent models of psychoses and highlights the importance of analysing the effects of different characteristics of the repeated treatment.

Gender differences in the effects of haloperidol (0.07S mg/kg per day for 5 days) on avoidance conditioning were evaluated. We also studied performance of the subjects free of the drug and the acute effects of haloperidol in animals trained without drug 48 h after the last haloperidol administration. Latencies of escape and avoidance responses, number of nonresponses, escapes, avoidances, crossings during the adaptation period, crossings during intertrial intervals, and total crossings per minute were analyzed. This dosage impaired conditioning of the male animals but did not attain the same effects on females. Haloperidol did not deteriorate performance of the task when it had been learned previously without drug. The results confirm the existence of gender differences in haloperidol effects on avoidance conditioning in mice and suggest that these differences are related to the learning process and not only to the impairment of motor behavior characteristic of neuroleptic drugs.

A. SALVADOR AND V. M. SIMON. Successful intermale aggression and conditioned place preference in mice. PHYSIOL BEHAV 58(2) 323-328, 1995.--This study assessed the reinforcing properties of successful intermale agonistic encounters between OFI male mice using the conditioned place preference paradigm. A three compartment apparatus was used and the procedure consisted of three phases: preconditioning (3 days), conditioning (8 days) and postconditioning (3 tests). Individually housed male mice were allocated to two groups. The aggression group confronted docile opponents in the preconditioning "less-preferred" compartment and were left alone in the "preferred" one. The control group was left alone in both compartments. Whereas no significant differences were found between both groups in the time spent in the less-preferred compartment, a separate analysis of animals in function of the color of the less-preferred compartment revealed a clear-cut difference. Mice developed a conditioned place preference for the aggression-paired compartment only if that experience took place in the black one. These findings suggest that the process of establishing a conditioned place preference with successful intermale aggression as reinforcer is extremely fragile and can be easily disrupted by changing the environmental cues involved.

Chronic exposure to mild unpredictable stressors (CMS) has previously been found to reduce the consumption of palatable, sweet solutions in rats. In the present study, the utility of this procedure was assessed in mice. Male AP mice subjected to CMS showed reduced consumption of a 2% or 4% sucrose solution. This effect was reversed by chronic (3 weeks) treatment with the tricyclic antidepressant imipramine (20 mg/kg per day). These results extend previous reports of a generalized decrease in sensitivity to reward (anhedonia) in rats caused by CMS and the efficacy of antidepressant treatment in this paradigm. Chronic unpredictable mild stress in mice appears to provide a realistic animal model of depression.

This study assessed whether two types of non-aggressive “standard opponents” (“intact” and “anosmic” group-housed males) produced similar behavioral changes in isolated OF1 male mice given several experiences of victory. Experimental groups confronted either intact or anosmic opponents every two days until they had completed four encounters. The behavioral changes were recorded using a detailed ethologically inspired analysis. These changes were clearly different depending on the opponent type. When intact opponents were used, experimental subjects increased the time spent in digging, non-social exploration, explore from a distance, and attack over encounters, but showed decreased time spent in threat and a decreased latency to the first attack. In encounters with anosmic opponents, only declines in the latencies to threat and attack were noted. Moreover, the experimental groups differed in their behaviors over encounters. Those confronting intact opponents spent less time in social investigation, more time in explore from a distance and threat, and showed a shorter latencies to threat and attack than counterparts confronting anosmics. These results suggest that, although both types of “standard opponents” are similar in their non-aggressiveness, they elicit rather different behavioral responses in their adversaries. These findings provide additional support for the view that the type of opponent used in studies on intermale aggression is of paramount importance. Indeed, the use of different types of “standardized non-aggressive opponents” appears to be an important source of variability between studies. © 1994 Wiley-Liss, Inc.

1. Although it is accepted that dopaminergic antagonists suppress aggressive behaviour, the drugs used have been relatively non-selective or specific to the D2 receptor. 2. The selective D1 antagonist, SCH 23390, makes it possible to evaluate the impact of this receptor on aggressive behaviour. 3. The effects of SCH 23390 and Spiperone (a D2 antagonist) on the aggressive behaviour of mice were assessed employing a “standard opponent” test. 4. Both drugs markedly decreased aggressive behaviour whilst increasing immobility. However, whilst SCH 23390 increased immobility to a small extent, Spiperone, produced a general decline in active behaviours. 5. It appears that the D1 receptor inhibition of aggression is the more specific.

The effects of a single injection of morphine hydrochloride (0.3, 0.6, or 1.25 mg/kg) or physiological saline (0.9% NaCI) on the agonistic behaviour elicited by isolation in male mice were examined. Individually housed mice were exposed to anosmic “standard opponents” 30 minutes after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. Morphine (at 0.6 and 1.25 mg/kg) significantly and dose-dependently decreased time spent in offensive (“threat” and “attack”) and “digging” behaviours but markedly increased “non-social exploration” without a significant increase of “immobility.” The lowest dose was completely ineffective in producing changes in any of the behaviours studied. It is concluded that these results present a specific ethopharmacological profile characterized by suppression of aggressive behaviour, increase in non-social explotation, and no evident impairment of motor activity. © 1993 Wiley-Liss, Inc.

Clinical studies have shown clozapine to be effective in the treatment of schizophrenia and associated with an extremely low incidence of extrapiramidal side effects. Diverse studies indicate that clozapine is an atypical neuroleptic with a preferential activity on the mesolimbic structures and a lower affinity for striatal D2 receptors than the classical antipsychotics. The purpose of this study was to assess the behavioral properties of clozapine, especially its effects on aggressive and motor behaviors. Individually housed male mice of the OF1 strain were exposed to anosmic “standard opponents” 30 minutes after the last drug administration. One category of animals received a single IP dose of the compound (0.2, 0.5, 1 or 1.5 mg/kg). Another category received daily doses (0.5, 1 or 1.5 mg/kg) for 21 days. Encounters were videotaped and behavior evaluated using an ethologically based analysis. Clozapine, in the acute treatment condition, produced a significant decrease in “attack” and “threat” behaviors without “immobility” being significantly increased. These results suggest a rather specific antiaggressive action of the compound with little motor impairment. In the chronic administration, no significant change in aggressive behavior was observed which may be attributed to the development of some degree of tolerance.

The atypical neuroleptic, sulpiride is a selective D2 antagonist, having a preferential action on mesolimbic regions. The effects of acute and chronic treatment with sulpiride on aggressive behaviour in male mice were studied using an ethologically based analysis. It was hypothesized that sulpiride would diminish "threat" and "attack" but would not produce marked "immobility", because of the mesolimbic effect referred to above. Isolated albino male mice (experimental animals) were confronted by "standard opponents". Acutely-treated experimental animals received an intraperitoneal injection of sulpiride (20, 50 or 100 mg/kg) 30 min before testing. Chronically-treated animals received sulpiride (10, 20 or 50 mg/kg) once a day for 7 or 14 consecutive days. Acute treatment with sulpiride had an obvious antiaggressive effect, with significantly decreased time devoted to "attack" and "threat" behaviour. Although time spent in "immobility" was modestly increased, the time devoted to other motor behaviour was also increased. Chronic treatment for 1 or 2 weeks did not change any behavioural category, except "immobility". The antiaggressive action of acutely administered sulpiride is interpreted as a relatively specific dopaminergic antagonist effect and not as merely a non-specific correlate of its disruptive action on motor behaviour. The possible anxiolytic action of sulpiride is also discussed.

The literature of the effects of dopamine antagonists on escape-avoidance, focusing on data obtained in our laboratory with male and female mice, is reviewed. The acute administration of haloperidol, raclopride, clozapine, and SCH 23390 impaired escape-avoidance behavior more in males than in females, and the subchronic administration of haloperidol had a similar effect. This appeared to be a reliable phenomenon, because it was observed in both kinds of administration, in two mouse strains, and with several drugs and doses. The observed results were dose dependent, although the dose–effect relationship was not the same in all drugs. The sex differences in escape avoidance did not seem related to sex differences in the well-known deteriorating effects of these drugs on motor activity. In addition, an analysis of all our studies showed that there were no sex differences in the variability of responses, reinforcing the idea that female subjects should be included in these types of studies.

In various species, competitive encounters influence hormonal responses in a different way depending on their outcome, victory or defeat. This study aimed to investigate the effects of sports competition and its outcome on hormonal response, comparing it with those displayed in situations involving non-effort and non-competitive effort. To this end, serum testosterone (T), cortisol (C) and prolactin (PRL) were measured in 26 judoists who participated in three sessions (control, judo fight and ergometry). The relationship between hormonal changes and psychological variables before and after the fight were also analysed. Our results showed a hormonal response to competition, which was especially characterized by an anticipatory rise of T and C. Depending on outcome, significant higher C levels were found in winners in comparison to losers through all the competition but not in T or PRL, both groups expending a similar physical effort. Furthermore, similar hormonal responses to the fight and to a non-competitive effort with the same caloric cost were found, other than with PRL. Winners showed a higher appraisal of their performance and satisfaction with the outcome, and perceived themselves as having more ability to win than losers, although there were no significant differences in motivation to win. Finally, the relationships found between T changes in competition and motivation to win, as well as between C response and self-efficacy suggest that in humans hormonal response to competition is not a direct consequence of winning and losing but rather is mediated by complex psychological processes.

Anabolic-androgenic steroid abusers have reported hyperactivity euphoria, and decreased fatigue, among other behavioral effects. It has been suggested that the effects of these substances on the central nervous system are similar to those of psychostimulants; however, the influence of steroids on general locomotor activity in laboratory animals is not well understood, especially how noncastrated male rodents are affected. In this study, spontaneous locomotor activity displayed by gonadally intact male mice submitted to several experimental conditions was analyzed. Different housing conditions (individual or cohabiting with a female), diverse steroids (testosterone propionate, nandrolone decanoate, and a mixture of both steroids) and single or repeated injections were employed. At 24 hours after the injection (after the three last injections in the case of chronic treatment) spontaneous locomotor activity was registered on an activity recorder for one 15-min. period. No effects due to the treatment were found in almost every experimental condition. These results contrast with the dramatic decreases in activity described for female mice after treatment with such steroids. It seems that in intact males the steroids' influence on spontaneous locomotor activity may be more subtle than expected. These effects seem very complex, depending on duration of treatment and specific situations (spontaneous or forced activity) as well as the interaction with endogenous androgen levels.

Effects of testosterone propionate, an anabolic-androgenic steroid (AAS), on aggression in gonadally intact male mice were examined. Animals were given weekly injections of 3.75, 7.5, 15, and 30 mg/kg of drug or sesame oil for 10 weeks. During the last 3 weeks, behavioral tests were conducted and at the end of the experiment, body, liver and testes weight and hormonal data were collected. The treatment had minimal behavioral and endocrine effects. It resulted in shorter latencies of 'threat' only in the last agonistic encounter, increases in testosterone levels and decreases in testes weight in a non-linear dose-dependant way. The action of treatment was different on threat and attack, the latter being unaffected. The behavioral effects in the total sample were only found in aggressive animals selected on the basis of their latency of attack in the first encounter.

In this study, the antiaggressive effects of risperidone and SCH 23390 have been explored. Using the paradigm of isolation-induced aggression, 150 albino male mice of the OF1 strain were allocated to control and experimental groups which received three doses of risperidone (0.01, 0.05 and 0.1 mg/kg) or two doses of SCH 23390 (0.05 and 0.1 mg/kg). Only the highest doses of risperidone decreased threat and attack behaviours but all doses significantly impaired motor behaviour. SCH 23390 decreased attack with the two doses used and also produced significant increases in immobility. Although both antipsychotics are antiaggressive, this action seems to be more specific in the case of risperidone. Finally, both drugs failed to affect animals with short attack latency, being antiaggressive only in subjects with long attack latency, which suggests that these two types of animals are different in their dopamine and serotonin neurotransmission.

The effects of morphine (6.3, 12.6, and 25.2 mg/kg) on active avoidance behavior of BALB/C mice are explored in three acquisition sessions and in two subsequent performance sessions. Morphine-treated animals showed an increase in avoidance acquisition with respect to control group without differences in performance. However, a dramatical, concomitant rise in the locomotor activity of the animals (increase in the number of crossings during the intertrial intervals) prompted us to transform the data employing a formula with which a measure of actual learning was obtained. Applying this formula, we have observed that morphine administration impairs, dose-dependently, acquisition and performance of avoidance. Thus, the impairing effects of morphine on avoidance could be masked by their stimulant effects on locomotor activity.

To further clarify the interaction between opioid and dopaminergic systems, the effects of simultaneous administration of morphine hydrochloride (1.25 or 2.5 mg/kg) and haloperidol (0.1 mg/kg) on aggressive behavior of male mice were explored. Isolated male mice (experimental animals) were confronted in a neutral area with anosmic, group-housed consepecifics (standard opponents) 30 min after injection of both compounds, and aggression was evaluated by estimation of times allocated to 11 different behavioral categories. In the first experiment (which functioned as a pilot study), the two doses of morphine were explored. In the second one, incorporating a more complete experimental design, only the lowest morphine dose was used and the animals were preselected by a previous aggression test. In attack behavior, morphine added to haloperidol counteracted, at least partially, the antiaggressive effect of the neuroleptic. In contrast, the impairing effects of haloperidol on motor activity were increased by the addition of morphine. These results show that the behavioral effects of dopaminergic antagonists are modulated by opioid influences and that opiates and dopaminergic agents interact in a different manner on motor and on aggressive behaviors.

The effects of three acute doses of D-amphetamine (0.25, 1.5 and 3 mg/kg) were studied in a model of isolation-induced aggression in male mice. An ethopharmacological analysis of the encounters was carried out, which studied the frequency, total and mean duration of different behavioral categories, including the temporal distribution of attacks and the duration of inter-attack intervals. The results show a reduction in the total and mean duration of the Attack category and an increase in motor activity manifested by longer durations, both total and mean, of Non Social Exploration and shorter Immobility. The temporal analysis of Attack revealed an increase in the number of very short (< 15 s) inter-attack intervals and a temporal redistribution of the attacks to later in the course of the social encounters. These results confirm for a complex behavior such as aggression, that D-amphetamine, even at low doses, favors a fragmentation and repetition of motor routines with a simultaneous reduction in the influence of environmental cues on the control of behavior.

The effects of scopolamine hydrobromide (0.5 and 2 mg/ kg) administered intraperitoneally to Balb/c male mice before or after training in active avoidance were explored in four training sessions and in a subsequent test session, free of drug. Animals given scopolamine prior to training performed better than controls, an effect that was reversed in the session free of drug. However, a deeper analysis of the data permits us to interpret this increment in the number of avoidance responses as a consequence of the increase in activity produced by the drug and not as learning. In the animals injected with scopolamine after sessions no effects were observed. In conclusion, the results of the present experiment confirm that scopolamine produces an impairment in the acquisition of an active avoidance task, but also show that this impairment can be easily masked by the facilitating effects of the drug on activity.

1. Repeated doses of the anabolic-androgenic steroid stanozolol were assessed for their effects on agonistic behavior, motor activity, and body weight in both young and adult male laboratory mice. 2. Stanozolol significantly increased weight gain in young, but not older subjects, especially at the highest doses. 3. There were, however, no significant differences in motor activity or in ethologically assessed social behavior (including aggression) in young or adult mice.

Raclopride is a substituted benzamide with high selectivity as an antagonist of central dopaminergic D 2 receptors and potential antipsychotic effects. In comparison with a classic DA receptor blocking agent like haloperidol, raclopride displays an atypical profile in preclinical tests for extrapyramidal side effects. Antiaggresive properties of raclopride on agonistic behavior have not yet been fully explored. In this work the effects of raclopride (0.1, 0.3, or 0.6 mg/kg) on aggressive and motor behaviors in male mice were studied. Aggression tests were performed 30 min after injections. Encounters were videotaped and behavior was evaluated, measuring the time spent in 11 broad categories of behavior. The results show a clear antiaggressive effect of raclopride, with very little motor impairment and some increase in exploratory behavior. This behavioral profile is very similar to the one observed with other atypical neuroleptics and differs somewhat from that found in the classic compounds.

The study of the temporal course of tolerance development was used as a means to separate different aspects of the action of haloperidol on social behavior. Agonistic behavior was studied in isolated male mice that confronted standard opponents (anosmic and grouped conspecifics) in a neutral area. The aggressive and motor behaviors of the experimental animals were evaluated 30 min or 24 h either after a single injection of haloperidol (0.4 mg/kg) or following the last of a series of 15 or 30 injections. When animals were evaluated 30 min after the haloperidol injection, no tolerance to the antiaggressive effects was evident. The action on immobility, on the contrary, showed a clear tolerance development with repeated drug administration, both with 15 and 30 injections. When evaluated 24 h after the last injection, tolerance to the antiaggressive effects developed with repeated injections. Increased immobility was never found in the tests carried out after 24 h, not even in the single injection group. The clear divergence found in the temporal courses of tolerance to haloperidol in its antiaggressive and motor effects that these actions are mediated through different neurophysiological mechanisms. A parallel with extrapyramidal and therapeutic effects is discussed.

Gender differences in the disruptive effects of haloperidol on some reinforced behaviors have been observed in different species. However, the inhibitory action of haloperidol on the acquisition and performance of escape-avoidance behavior has only been investigated in male subjects. The present experiment was designed to investigate possible gender differences in the effects of haloperidol on the initial phase of an escape-avoidance learning task. Male and female mice of the OF1 strain were given a single training session in a shuttle-box. Thirty minutes prior to the behavioral test, mice were injected IP with haloperidol (0.25 mg/kg) or physiological saline (10 ml/kg). Latencies of escape and avoidance responses and the number of nonresponses, escapes, avoidances, pseudoavoidances, crossings during the adaptation period, and crossings during intertrial intervals (ITIs) were evaluated. The disruptive action of haloperidol on the escape-avoidance behavior of the mice was greater in males than in females. The number of nonresponses were higher and the number of escapes lower in treated males than in their female counterparts. These gender differences were not found in control subjects. Activity measures of spontaneous motor behavior (crossings in the adaptation period and during ITIs) did not present gender differences either. Several possible mechanisms responsible for this greater susceptibility of males to the inhibitory effects of haloperidol on escape-avoidance learning are discussed, especially the modulating role of female hormones on dopaminergic activity.

The effects of a range of antiandrogens and antiestrogens on conflict behaviors in laboratory rats and mice are reassessed in the light of recent studies applying ethophamacological analyses (recording the full spectrum of behaviors) to such investigations. It is argued that any antihostility properties of the antiandrogen cyproterone acetate are largely a consequence of indirect actions on odor communication, whereas antiestrogens (e.g., tamoxifen and CI 680) seem to have more fundamental motivational effects in addition to communicatory actions. A detailed example of the approach is provided in which progesterone (which can be antiandrogenic) is given to rats paired in different ways. The type of pairing has a very substantial effect on the actions seen after treatment, and the ethopharmacological approach generates a better picture of antihormone effect than traditional psychopharmacological tests.

The possibility that antipsychotic drugs antagonize the behavioural effects of stress on agonistic behaviour has been explored. Male mice of the OF.1 strain were subjected to the following treatments: 1) Immobilization stress (ten or twenty minutes in duration), 2) haloperidol (three doses) and 3) immobilization stress (ten minutes) plus haloperidol. Individually housed experimental animals confronted standard opponents (anosmic animals) in ten-minute encounters in a neutral cage. Encounters were videotaped and behaviour evaluated, assigning times allocated by subjects to eleven broad behavioural categories. The data show that stress markedly decreases attack behaviour, but haloperidol does not protect against the disruptive action of immobilization. On the contrary, stress and haloperidol produced additive effects further decreasing attack and increasing immobility.

The effects of acutely administered benzodiazepines have largely been validated in male animals, in spite of the fact that the majority of anti-anxiety drugs are prescribed for female patients. A study was carried out assessing the potential of female mice in the testing of the anxiolytic properties of drugs. Three doses (0.5, 1.0 and 2.0mg/kg) of the benzodiazepines diazepam and nitrazepam were given to individually-housed female Swiss mice before dyadic encounters with anosmic, group-housed males. Videotape analysis of the encounters, using an ethopharmacological technique, revealed suppressive effects of diazepam (1.0 and 2.0mg/kg) and nitrazepam (all doses) on avoidance/flee, confirming the anxiolytic properties of these drugs. However, some doses of diazepam (2.0mg/kg) and nitrazepam (1.0mg/kg), greatly increased immobility with little effect on active behavioural elements. It is suggested that "immobility" does not simply measure sedation.

Departamento de Psicologia Fisiologica (A.S., V.S., F.S.) and Laboratorio de MedicinaNuclear e Isotopos (L.L.), Hospital Clinico Universitario, Universitat de Valencia, Valencia,SpainSerum testosterone and cortisol levels were measured by radioimmunoassay in 14young male judo competitors, in samples taken 10 minutes before and 45 minutes aftertwo different pr(Redures. The first involved physical exercise and the second competi-tive fighting. Both procedures were of 5 minutes duration and sessions took plate atthe same time (between 10:00 \.M. and 12:00 P.M. liR-al lime) but on different days.Comparing the two situations over all subjects revealed that testosterone increasedafter exercise and decreased slightly after competition. Between subject comparisonssuggested that contrary to previous claims, winning or losing did not significantlychange the testosterone and cortisol levels. Comparisons of subjects who were membersof the Regional Team with individuals who were not part of thai gronp confirmed thatmemhers increased their testosterone levels after competition, whereas the nonniem-bers showed a significant decrease. Moreover, success of the individuals, in theirsporting record, correlated positively and significantly with the changes of testosteroneohserved during the competition. These preliminary results suggest that previouspersonal experience of success can infiuence the pattern of the psychoend(KTine re-sponse to a contest situation.Key words: physical exercise, judo competition, victory, defeatINTRODUCTIONPhysiological responses to the experiences oi victory and defeat include the modi-fication of circulating levels of some hormones. Clinically, sporting competitions havebeen seen as suitable situations to study hormonal responses to winning and losing.Mazur and Lamb 11980] found that the pattern in changes of testosterone was differentin winners and losers of a tennis match. Winners generally showed increases andlosers decreases in titers of this steroid and significant differences were evident I to2 hours after the match. Hlias [1981] found that subjects winning a wrestling matchshowed significantly greater increases than losers when he compared percentagechanges between testosterone levels seen 10 minutes before and 10 minutes after thematch. Winners also showed significantly greater increases in cortisol than losers.

Recent studies suggest that motivations for certain forms of masculine behavior including social aggression are mediated by central estrogen receptors. Two studies using antiestrogens in rodent species were performed. Intact male LH rats were given Tamoxifen or vehicle for 4 or 8 days. The three possible pairings were videotaped for 60 min. Intact male OF1 mice were given CI-680 or vehicle over 25 days. Similar pairings were carried out but some CI-680 or vehicle animals were paired with anosmic opponents. Encounters were videotaped for 10 min. In both experiments evidence was obtained that the antiestrogen markedly reduced time allocated to offense. Any variations in defense were a consequence of the level of attack to which animals were subjected. Neither compound greatly influenced the androgen-dependent sex accessory glands. Antiestrogens consequently have potential as antihostility agents in some forms of attack.

An attempt was made in two experiments to reinvestigate the effects of the antiandrogen cyproterone acetate (CA) on mouse social behavior in a variety of ethologically-assessed paired encounters. The data confirm that CA reduces offense (threat and attack) in animals when both subjects receive the material but that CA has no such action in other pairings. This suggests that CA's major suppressive effect on "hostility" is expressed in mice via a reduction in "attack-promoting" pheromone production. Indeed, there was evidence in the more chronic study that CA, could augment (via a central mechanism?) offense in subjects paired with docile anosmic opponents. Changes in defense were largely responses to variations in the degree of attack to which animals were subjected. The antihormone also had actions on other aspects of behavior including sexual activity, social investigation and immobility in such tests. CA had a potent suppressive action on the weights of sex accessory glands. The data do not suggest that CA can be used as a specific antihostility agent.

An apparatus for the study of avoidance conditioning in fishes is described. The chamber is cylindrical in shape, with shocking electrodes placed above and below the animals, and response is defined as swimming a predetermined distance in either direction along a circumferential path. This apparatus has several advantages over the conventional shuttlebox: (1)There is little constraint on the direction of swimming; (2) the magnitude of response (swimming distance) required for avoidance can easily be varied over a wide range; and (3) variation in the effectiveness of shock with the position of the animal relative to the position of the electrodes is minimized. Some sample data obtained in a free-operant experiment with goldfish are presented.

The potential influence of the type of opponent used in intermale aggression encounters to assess the actions of drugs was examined. Two experiments were carried out, one with the antiandrogen Cyproterone Acetate and the other with the antioestrogen CI-680 (both administered every three days over 25 days). In both experiments the antihormone-treated subjects encountered different opponents, namely: a) an antihormone-treated male, b) a non aggressive anosmic male or c) a vehicle-treated male. Vehicle-treated subjects also confronted a vehicle-treated or an anosmic opponent. The behaviour displayed by antihormone-treated subjects varied according to the characteristics of the partner, suggesting that the effects of drugs might be interpreted differently depending on the type of animal employed as an adversary. In fact, some of the apparently contradictory results reported in the literature seem to be consequences of the utilisation of different kinds of opponents. It is concluded that the choice of the opponent is of paramount importance in the study of drug actions on intermale aggression tests and that using more than one type of opponent can provide more complete information about the actions of particular drugs.