Effects of environmental enrichment on cognitive performance of pigs in a spatial holeboard discrimination task

This study investigated the effects of environmental enrichment on the cognitive performance of female conventional farm (growing) pigs in a spatial holeboard task. Ten pairs of littermates matched for weight were used. From each litter, one piglet was randomly assigned to a barren environment; the other was assigned to an enriched environment from 4 weeks of age. The enriched environment was double the size of the barren environment, had a floor covered with straw, a rooting area filled with peat, and one of the four different enrichment toys which were exchanged daily. Starting at 11 weeks of age, all pigs were tested in a spatial holeboard discrimination task in which 4 out of 16 holes were baited. Furthermore, basal salivary cortisol levels of all pigs were determined after the end of all testing. All pigs were able to acquire the pattern of baited holes (acquisition phase, 40 trials) and the diagonally mirrored pattern (reversal phase, 20 trials). During the acquisition phase, the reference memory performance of the enriched-housed pigs was better than that of their barren-housed littermates, i.e. they reduced visits to the unbaited set of holes. During the reversal phase, enriched-housed pigs had a better general working memory performance than the barren-housed pigs as indicated by reduced revisits to holes already visited during a trial, irrespective of whether they were of the baited or the unbaited set. The enriched-housed pigs also searched for the hidden bait faster during both phases. The environments did not affect basal salivary cortisol levels. In conclusion, environmental enrichment slightly improved the cognitive performance of pigs in a spatial learning task. We hypothesise that the long period of habituation to and testing in the holeboard acted as enrichment that partially reduced the effects of barren housing.     

Naturalistic treatment of an autistic child

The present research experimentally evaluated a "naturalistic" treatment program for an autistic child administered by the parents over a 2-yr period. Operant reinforcement techniques previously developed and tested in laboratory settings were initially assessed in a clinic and eventually in the family's home. Experimental manipulations were performed in both settings on rituals, crying and whining, compliance, non-verbal imitation, and verbal imitation. The results clearly indicated that parents can effectively treat autistic behaviors provided that they receive adequate training and supervision in operant reinforcement therapy, and provided that sufficiently potent reinforcers are available to maintain behavior.     

Speech acquisition in a nonverbal isolate child

The present study attempted to evaluate experimentally the relationship between two response classes: cooperative play and speech. One child was observed in a preschool free-play setting. Base rates of speech and play with peers indicated that the child never spoke to or played with peers during free-play periods. Base rates of teacher attention were observed to fluctuate directly with the child's isolate play. When differential attention and extinction operations were presented, removed and presented again, the frequency of cooperative play with peers increased, decreased and increased accordingly. Moderate fluctuations in verbal behavior also correlated with the presence and absence of the differential attention and extinction operations, even though the operations were applied only to cooperative play. The results suggest that some nonverbal isolate children may begin producing speech when play behaviors with peers are reinforced by teachers.     

A method for recording verbal behavior in free-play settings

The present study attempted to test the reliability of a new method of recording verbal behavior in a free-play preschool setting. Six children, three normal and three speech impaired, served as subjects. Videotaped records of verbal behavior were scored by two experimentally naive observers. The results suggest that the system provides a means of obtaining reliable records of both normal and impaired speech, even when the subjects exhibit nonverbal behaviors (such as hyperactivity) that interfere with direct observation techniques.     

Predicting Divorce among Newlyweds from the First Three Minutes of a Marital Conflict Discussion

This study tested the hypothesis that how a discussion of a marital conflict begins--in its first few minutes--is a predictor of divorce. The marital conflict discussion of 124 newlywed couples was coded using the Specific Affect Coding System, and the data were divided into positive, negative, and positive-minus-negative affect totals for five 3-minute intervals. It was possible to predict marital outcome over a 6-year period using just the first 3 minutes of data for both husbands and wives. For husbands this prediction improved as the groups diverged in the remaining 12 minutes; for wives the prediction remained equally powerful for the remaining 12 minutes as it had been in the first 3 minutes.     

Adult discipline as a factor in childhood imitation

The present study examined changes in two children's imitative behavior as a function of the model's use of timeout and differential attention. Subjects were two children, one classified by her parents, the other classified by his teacher, as highly oppositional to adult requests or commands. The former child was treated by the parents in the home setting; the latter child was treated by the teacher in a preschool setting. Results showed that the children's oppositional behavior varied predictably with the presence and absence of adult use of time-out and differential attention. As expected, imitative behavior of both children was greater during treatment periods than during baseline periods.This research was funded in part by a Faculty Research Grant from the Graduate School, University of Tennessee, Knoxville. We would like to extend our appreciation to Nancy Williams, Andrea Warming, Ursula Botbyl, Diane Childress, Tom Hunter, and Edward Fowler who served as observers, and to Ronda Warner who worked with Ernest in the University Nursery School.     

Judgement bias in pigs is independent of performance in a spatial holeboard task and conditional discrimination learning

Biases in judgement of ambiguous stimuli, as measured in a judgement bias task, have been proposed as a measure of the valence of affective states in animals. We recently suggested a list of criteria for behavioural tests of emotion, one of them stating that responses on the task used to assess emotionality should not be confounded by, among others, differences in learning capacity, i.e. must not simply reflect the cognitive capacity of an animal. We performed three independent studies in which pigs acquired a spatial holeboard task, a free choice maze which simultaneously assesses working memory and reference memory. Next, pigs learned a conditional discrimination between auditory stimuli predicting a large or small reward, a prerequisite for assessment of judgement bias. Once pigs had acquired the conditional discrimination task, optimistic responses to previously unheard ambiguous stimuli were measured in the judgement bias task as choices indicating expectation of the large reward. We found that optimism in the judgement bias task was independent of all three measures of learning and memory indicating that the performance is not dependent on the pig’s cognitive abilities. These results support the use of biases in judgement as proxy indicators of emotional valence in animals.     

Self‐Reported Family Socioeconomic Status,the 5‐HTTLPR Genotype,and Delinquent Behavior in a Community‐Based Adolescent Population

Twin and adoption studies have demonstrated a significant contribution of both genetic and environmental factors to antisocial and delinquent behavior. Associations have been reported between the serotonin transporter (5‐HTT) and aggression, and between socioeconomic status (SES), aggression, and serotonergic functions of the brain. We aimed to investigate associations between the 5‐HTTLPR genotype and family SES in relation to delinquent behavior among adolescents. A total of 1,467 17‐ to 18‐year‐old students in the county of Västmanland, Sweden, anonymously completed a questionnaire and gave a saliva sample. Family SES had a U‐shaped relation to delinquency, where adolescents with low and high family SES were the most delinquent. There were curvilinear interactions between the 5‐HTTLPR genotype and family SES in relation to delinquency. Among individuals having high family SES, boys with the LL (homozygous for the long allele) or LS (heterozygous) genotypes and girls with the SS (homozygous for the short allele) or LS (heterozygous) genotypes showed the highest delinquency scores. Among individuals having low family SES, boys with the LL (homozygous for the long allele) genotype and girls with the LS (heterozygous) genotype showed the highest delinquency scores. The present study suggests evidence for an interaction between family SES and the 5‐HTTLPR genotype in relation to juvenile delinquency. Aggr. Behav. 39:52‐63, 2013. © 2012 Wiley Periodicals, Inc.     

Visibility distances with halogen and conventional headlights

Abstract.— Using visibility distance as a criterion, halogen and conventional continental European high and low-beam headlights were compared in a series of field experiments. On high-beam without opposing light the halogen headlights offered about 25% longer visibility distances than the conventional headlights. With both opposing cars using low-beam there was a slight advantage (<5 m) in favour of halogen headlights. The optimal dipping distance was a function of high-beam system (intensity) rather than low-beam system. Small differences in aiming, atmosphere etc. caused larger differences in visibility distance than did the headlight system.     

The modification of a child's enuresis: some response-response relationships

The present study attempted to evaluate experimentally the relationship between two response classes, enuresis and oppositional behavior. One child who had a long history of bed-wetting was observed in his home setting. Parents' reports and initial observations confirmed that the child was oppositional much of the time. When a timeout operation and differential attention were presented, removed, and presented again, the frequency of oppositional behavior decreased, increased, and decreased accordingly. Fluctuations in enuretic activity also correlated with the presence and absence of the timeout and differential attention operations. The suppression of oppositional behavior and enuretic activity persisted over an 18-month treatment period. It was suggested that the parental operations performed on oppositional behavior may have led to an increase in the parents' social reward value. Cessation of enuretic activity was explained in terms of a shift in parental reinforcer effectiveness.