Maintained aggressive behavior in gonadectomized male Siamese fighting fish (Betta splendens)

Adult male Betta splendens were gonadectomized and tested twice for aggressive behavior two weeks later. In a mutual viewing test environment, it was found that gonadectomized animals maintained their aggressive behavior on all six indices of aggression at a level equal to controls. Animals that showed some testis regeneration and sham operated fish were also equal to controls. The results are interpreted to mean that adult aggressive behavior in male B. splendens may not be under the control of gonadal hormones. Pituitary gonadotropins, interrenal gland, and critical period hypotheses are given as possible explanations of the maintained aggressiveness following castration.     

Interaction of cholecystokinin with vasoactive intestinal peptide in body shaking response to ice-water immersion in rats

Interaction of cholecystokinin (CCK) with vasoactive intestinal peptide (VIP) in body shaking response to ice-water immersion was observed in pentobarbital-anesthetized rats. Although CCK itself had no influence on the response, VIP suppressed it and this effect of VIP was antagonized by simultaneous administration of sulfated octapeptide of CCK, but not by non-sulfated CCK.     

Acute effect of phenobarbital on escape behavior

Rats were trained to run in a straight alley to escape shock. Subsequently, phenobarbital was administered and more trials given. Phenobarbital retards running at all doses tested in a curve that is positively accelerating as a function of dose on the first trial. The first trial is markedly slower than later trials with the greatest effect occurring at the higher dosages.     

Effects of Behavioral Control and Type A Behavior on Cardiovascular Responses

The purpose of this study was twofold: (a) to examine the relationship between degree of behavioral control and cardiovascular changes in 60 adult males performing an anagram solution task, and (b) to assess the interaction between behavioral control and type of subject (A vs. B). Three conditions were used, differing from each other in the percentage of solvable anagrams (100, 50, and 30%). Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured before, during, and after the anagram task. In all conditions, during-task SBP, DBP, and HR were significantly elevated above baseline. Blood pressure (BP) elevations appeared to be curvilinearly related to degree of behavioral control, i.e., more elevated in the 50% than in the 100% and 30% conditions. HR changes did not differ among conditions. Concerning the Type A behavior pattern, the results revealed significantly greater BP elevations for Type A than for Type B subjects, especially in the 50% condition, thereby confirming that the physiologic correlates of Type A behavior are predominantly evoked in challenging circumstances. Findings were discussed in the light of results of cardiovascular and endocrinological research. Consideration was given to the possible role of disengagement in the 30% condition and to differences in the pattern of responding between As and Bs.     

Effects of dietary nutrients and foraging costs on meal patterns of rats

Rats were fed either a cereal-based or a purified casein-based diet in a foraging paradigm in which the costs of procurement and consumption were varied. The group offered the cereal-based diet consumed about 10% more calories than the group offered the casein-based diet, but both groups grew at the same rate. The intake of a control group offered a choice between the two diets was approximately 80% from the casein diet, and the growth of this group did not differ from that of the experimental groups. Variations in the cost of procurement and the cost of consumption affected the patterning of meals differentially for the two diets: changes in meal patterns tended to control the time and/or energy spent feeding. These results show that (1) meal patterns in the foraging paradigm are sensitive to subtle differences in diets, and (2) the amount of diet consumed (acceptance) and the choice between diets (preference) are determined by the economics of feeding and the nutritive quality of the foods, as well as by their palatability.     

Exposure to extremely low-frequency electromagnetic fields improves social recognition in male rats

The effect of exposure to low-frequency electromagnetic fields (ELF EMFs) on social recognition was studied. The test was based upon a comparison between two encounters of an adult rat and a conspecific juvenile, separated by an interexposure interval (IEI). The exposure to ELF EMF of 1 mT intensity during 2 h for 9 days increased the duration of short-term memory of adult male Wistar rats up to 300 min. These data indicate, for the first time, that ELF EMF improves social recognition memory in rats.     

Adjustment in Childhood Brain Tumor Survival: Child, Mother, and Teacher Report

Examined the adjustment of 6- to 18-year-old children and adolescents(n = 38) 2 to 5 years postdiagnosis of brain tumor with respectto standardized measures of anxiety and depression; self-perceptions;and adaptive living skills. Child, mother, and teacher reportdata were used. Maternal adjustment (anxiety and depression,parenting stress) was also assessed. Children and adolescentssurviving brain tumors reported themselves to be generally withinthe normal range. However, maternal ratings of social problemswere higher than normative scores and significantly lower thannorms on social problems, scholastic competence, and communicationskills. Teacher ratings on the Teacher Rating Form were allwithin normal limits. Maternal adjustment measures were withinthe normal range, although the Parent-Child Dysfunctional Interactionsubscale of the Parenting Stress Index was elevated. No differencesin scores were found between children in regular and specialeducation, or between children who had received radiation andthose who did not. This sample of survivors of pediatric braintumors and their mothers had relatively mild problems in adjustment,supporting a competency-based view of the adaptation of pediatricpatients and their families.     

Alcohol Assessment in Psychiatric Patients

Alcohol use disorders in persons with co-occurring psychiatric disorders are associated with high rates of psy-chosocial instability and poorer treatment outcomes. Thus, assessment of alcohol use and abuse should become an integral part of psychiatric care. Because setf-report-based measures are frequently used, issues of reliability and validity in this population should be critically examined. The purpose of this article is to review and critique the existing empirical literature that has evaluated the psychometric integrity of self- report-based measures in psychiatric settings, and to outline a research agenda that promises to enhance the accuracy of alcohol assessment by persons receiving psychiatric treatment.     

Continuity and Change in Preschool ADHD Symptoms: Longitudinal Genetic Analysis with Contrast Effects

The genetic and environmental mediation of continuity and change in parent-reported ADHD symptoms were investigated in a cohort of over 6000 twin pairs at 2, 3 and 4 years of age. Genetic analyses of the cross-sectional data yielded heritability estimates of 0.78–0.81 at each age, with contrast effects. A common pathway model provided the best fit to the longitudinal data, indicating that genetic influences underlie 91% of the stable variance in ADHD symptomatology. In other words, what is stable for ADHD symptoms is largely genetic. Contrast effects acting in the same direction at different ages contributed to the observed continuity:longitudinal correlations were greater for dizygotic than monozygotic twins.The Twins Early Development Study is funded by the Medical Research Council.     

Behavioral treatment parameters with primary dysmenorrhea

Fourteen women with primary dysmenorrhea were administered four sessions of systematic desensitization (SD) by either a male or a female therapist. The following measures were taken during the flow periods before and after treatment and at a 6-month follow-up: menstrual symptom checklist, medication usage, invalid hours, and menstrual attitudes. At pretreatment, menstrually distressed women had significantly higher scores on all measures compared to a normative group and an explicitly nondistressed group. At posttreatment, treated women's scores on the dependent variables were significantly reduced. All indices were reduced to a nondistressed level at posttreatment and at 6-month follow-up. Type of dysmenorrhea (congestive vs. spasmodic), trait anxiety level, and therapist sex did not predict differential responsiveness to SD. SD did not affect frontalis EMG, peripheral blood flow, or pain threshold. A Retrospective Symptom Scale of menstrual distress was found to be highly reliable, valid, and sensitive.