Emotional correlates of selection for avoidance learning in rats.

The Roman high-avoidance (RHA) and low-avoidance (RLA) strains of rats were tested and compared with Maudsley reactive (MR) and non-reactive (MNR) strains to assess the relative contributions of emotionality and conditionability to differences between the two Roman strains. The RHA learned significantly faster in active avoidance, but slightly slower in passive avoidance, significantly faster in acquisition of an active approach task, but slighty slower in extinction of active approach tasks despite extensive adaptation and gentling. The RHA showed more 'rearing', more activity in the open field and more variety-seeking. Crossing with MNR showed the RHA less reactive in the open field. Results show RLA equivocal in conditionability, more emotional, and perhaps less active.

Positive short-term effects of activity on behaviour in chronic schizophrenic patients.

Forty schizophrenic patients were rated both by nurses (using the NOSIE) and by themselves on days soon after they had completed a period of activity. When compared with less active days, significant improvement was seen in most behaviours measured following activity, suggesting that activity is beneficial in the treatment of a population whose level of activity is restricted. Greatest improvement was found in less severely disturbed patients, more overweight individuals, females and those with lower levels of normal activity.

Eating disorders, perceived control, assertiveness and hostility.

There are anecdotal claims that eating disorder patients perceive themselves as highly controlled by the family and by society, but that they do not show assertive behaviour towards controllers. Anorexic and bulimic females were compared with female psychiatric patients, dieters and non-dieting controls on measures of eating disorder symptomatology, locus of control, assertiveness, inwardly directed hostility, family control and family encouragement of independence. Eating disorder patients reported significantly more external control, more inwardly directed hostility, less self-assertion and less family encouragement of independence than dieters and non-dieting controls, but they did not differ from psychiatric controls. Most of the characteristics seen in eating disorder subjects were also reported by psychiatric controls.

Cage design reduces emotionality in mice.

To see if a more natural cage design would alter the reactivity of laboratory mice, 192 mice were reared in cages with (1) no dividers, (2) five vertical dividers, (3) nine vertical dividers, or (4) nine vertical dividers and one horizontal platform. The mice preferred the most complex cages, and on almost all measures they were less emotional when reared in the more complex cages. Results suggest that a more natural housing environment would lead to healthier animals.

Transmission of B virus infection between monkeys especially in relation to breeding colonies.

Studies of B virus (Herpesvirus simiae) antibody in several species of macaque lead to the following generalizations. Newborn monkeys are not infected with B virus, even when born of seropositive mothers. Young monkeys remain uninfected until they become adults. The majority of adults develop B virus antibody unless their physical contact with seropositive adults is restricted. These observations are consistent with sexual transmission of B virus and classification of the disease in monkeys as venereal. However, infection at oral and dermal sites also occurs and may play a part in monkey-to-monkey transmission. Epizootics of B virus occurred during early attempts to start B virus-free breeding colonies. They appeared to originate from reactivated latent B virus in adult monkeys which had only low titres of antibody. The stress produced when groups of adult strangers were assembled to form breeding colonies was the most effective known inducer of latent B virus. Total exclusion of animals with any trace of antibody has enabled the establishment of new breeding colonies which are free from B virus.

Marathon runners' reaction to potassium iontophoretic experimental pain: pain tolerance, pain threshold, coping and self-efficacy.

There is equivocal evidence regarding pain responding in endurance athletes. When performing, their pain experience appears reduced but it is uncertain whether this persists when not competing or training. This study aimed to clarify how marathon runners perceive pain, and the influence of self-efficacy and coping strategy use on their pain threshold and tolerance when they are not affected by immediate exercise. Pain threshold and pain tolerance were assessed in 26 marathon runners and 26 age- and sex-matched non-runners using potassium iontophoresis as the experimental pain stimulus. Use of associative and dissociative coping strategies, and catastrophizing were assessed using the Cognitive Coping Strategies Inventory, and pain specific and general self-efficacy were measured. Elevated pain threshold, pain tolerance and self-efficacy in marathon runners were revealed. Pain specific self-efficacy accounted for 40% of the tolerance difference between the marathon and non-marathon groups. Coping and catastrophizing did not differ between the two groups but higher associative coping when accompanied by lower dissociative coping was related to higher pain tolerance. These results indicate that marathon runners have a reduced experience of pain compared with non-runners. This ability appears to be augmented by a high level of pain specific self-efficacy but is unaffected by the influence of general cognitive coping strategies, although higher associative coping and lower dissociative coping together were related to reduced pain tolerance independent of running involvement.

Therapy of isolate Rhesus: different partners and social behavior.

36 monkeys from 3 different rearing conditions were subdivided into 3 groups and then paired daily for 20 weeks either with others that were (a) socially sophisticated 9-month-old monkeys; (b) partial isolates, reared alone from birth for 9 months; or (c) socially naive 3-month-old infant monkeys. When 12 9-month-old partial isolates were thus split and tested, social play was greater in isolates paired with sophisticated therapists and least in isolates paired with isolate therapists. Fear showed the reverse pattern. Hostility was greatest in those infants, isolates, and sophisticates when paired with isolates and least in all groups when paired with infants. Of the nonisolate groups the infants were affected by their pairing the most, showing reduced social play when paired with the isolates, but increasing play when with sophisticates. Evidence is found against a learning or instrumental model of aggression production, and a novel theory is advanced suggesting that infants are genetically predisposed to acquire specific behavioral characteristics shown by the mother.

Dietary and metabolic effects on rhesus social behavior: protein and protein-calorie malnutrition.

Forty-seven monkeys were fed 1 of 8 diets between the ages of 1 and 7 months containing full-, half-, or quarter-strength protein or protein and calories using either casein or soy protein. While on the diet, malnourished infants were inactive both socially and nonsocially. When returned to a normal diet, previously malnourished subjects were more agonistic towards familiar peers but more friendly and less agonistic when later paired with unfamiliar monkeys. The data suggest that short periods of early severe malnutrition may protect the individual against adverse social conditions (e.g., isolation) and delay the development of normal social skills.

Dietary and metabolic effects on rhesus social behavior: phenylalanine-related dietary alterations.

Infant rhesus monkeys were (a) fed a diet high in phenylalanine or (b) fed a diet high in p-chlorophenylalanine for the 1st 12 months of life, (c) selected from mothers fed a diet high in phenylalanine during pregnancy, (d) fed a diet low in phenylalanine, (e) maintained as controls, or (f) maintained as pair-fed controls. Tested during the 1st year of life with familiar peers, during the 2nd year with unfamiliar stimulus animals and with a movie film, the 3 groups of phenylketonuric monkeys showed less play and other positive social behavior and more withdrawal and more aggressive behavior than did the 2 control groups. The results support learning data suggesting that phenylketonuric monkeys are more emotionally reactive.

Three social-preference measures in PKU monkeys.

Of twenty-four one-year-old rhesus, half were brain damaged from excessive phenylalanine (PKU) administered either pre- or post-natally. When compared on three measures of affiliation--(a) a simultaneous forced-choice proximity circus test, (b) a sequential free-operant Butler-box test, and (c) a social group in a playroom--the duration measure of the circus gave the best differentiation between stimulus animals, the Butler box the poorest. Both types of PKU monkeys were found to strongly prefer familiar PKU monkeys, and controls to refer unfamiliar followed by familiar controls. This extends preference research to induced brain damage and confirms behavioural abnormality in PKU macaques, an abnormality detectable by both humans and other monkeys.

Dietary effects on rhesus social behavior: altered amino acid diets.

Twenty-one monkeys continuously fed one of five diets high in tyrosine, histidine, alanine, glycine, or tryptophan between the ages of 1 and 12 months were compared with 20 controls. Social behavior either (a) while on the diet and tested in familiar groups of four or (b) while on a normal diet and paired with unfamiliar monkeys showed no effects of the high amino acid diets, confirming a previous analysis of learning ability.

Long-term learning deficits of mentally retarded monkeys.

During the first year of life, 12 rhesus monkeys were either subjected to diets high in phenylalanine or para-chlorophenylalanine either pre- or postpartum, leading to a condition similar to phenylketonuria (PKU); 12 other rhesus monkeys were controls. After removal from the PKU diets and return to normal diets for a period of 2 years, subjects were tested for learning ability on an extensive series of tasks. No support was found for suggestions that PKU monkeys (a) do worse if task difficulty is increased, (b) are less affected by negative reinforcement, (c) have an attentional or short-term memory storage deficit, and (d) do not attend to the relevant dimension. Support was found for the hypothesis that PKU subjects are more emotional, accounting for (a) disruption in performance following negative reinforcement and (b) difficulty in changing an initial or a learned response pattern.

Role of vision in social development in monkeys.

8 stump-tailed macaques were reared individually and either given all of their daily social experience in darkness (dark group) or given half their social experience in the dark and half in the light (controls). The dark group showed almost no aggressive behavior and less play than controls. Later, when all were tested in the light, the dark group were still less aggressive. Controls were less aggressive in the dark than in the light. There was no difference between the two groups in the form of the dominance hierarchy or the strength of preferences for social partners. This suggests that vision is especially important in the maintenance of assertive behaviors and in the instigation and the direction of aggressive behaviors, but relatively less important in other areas of social development.

Dietary and metabolic effects on rhesus social behaviour: neonatal thyroxine reductions.

Assessment was made of the behavioural development of 3 monkeys whose levels of thyroxine were reduced by being given 131I and another 3 monkeys given a thyroxine depressant (TCAP) during the first weeks of life and maintained with low thyroxine levels for 3 months. When subsequently tested at normal thyroxine levels, these experimental subjects showed less positive social behaviour when compared with controls. When confronted with unfamiliar monkeys, the two experimental groups were less fearful than controls and also showed a lack of differential responsiveness in varying social situations, suggesting a low level of emotion. A foetal athyreotic group is also described.