The effects of early handling on the partial reinforcement extinction effect and the partial punishment effect in male and female rats

Handled (Day 1-22) and non-handled infantile Wistar rats were tested in maturity for the partial reinforcement extinction effect (PREE) and the partial punishment effect (PPE). In Experiments 1 and 2, mature male and female rats were trained to run in an alley for food reward on a 1-trial/day schedule. In the PREE paradigm (Experiment 1), the partially reinforced group (PRF) received reinforcement on a quasi-random 50% schedule, while the continuously reinforced group (CRF) received reinforcement on every trial. In the test stage, both groups were given extinction training. In the PPE paradigm (Experiment 2), the partially punished (PP) group received, together with continuous reinforcement, shocks on a quasirandom 50% schedule, while the continuously reinforced group was reinforced on every trial. In test, all animals were given both reinforcement and shock on every trial. In Experiment 1, PREE—i.e. increased resistance to extinction in the PRF as compared to the CRF group—was more pronounced in the handled animals. More specifically, no PREE was obtained in the non-handled males, and in the non-handled females the PREE was reduced compared to the handled females. The results of Experiment 2 revealed no effect of handling or sex on PPE, that is, increased resistance to punishment in the PP group as compared to the CRF group was evident in all four conditions. In Experiment 3, handled and non-handled male rats were tested for the PREE using a multi-trial procedure in an operant chamber. PREE was obtained in the handled but not in the non-handled animals. The implications of these results for the differential effects of handling on male and female rats and the distinction between the PREE and PPE paradigms are discussed.     

Sex differences in reactions to outperforming same‐sex friends

The current studies were designed to examine whether female adolescents have more negative reactions than male adolescents to achieving more than their same‐sex friends. In Study 1, 51 females and 48 males from grades 8 and 10 were administered questions assessing their reactions to performing better than their closest same‐sex friends in four domains. Across domains, females reported more negative reactions than males. Further, compared with males, female participants believed that their same‐sex friends would have more negative reactions if they performed better than their friends. In Study 2, 48 females and 49 males age 18 years were asked how they felt about performing better than and equal to their closest same‐sex friends in the domains of romance and academics in both hypothetical and actual situations. Females reported feeling more positive when they received the same outcomes as opposed to better outcomes than their friends. Males did not differ in the valence of their responses to the two outcomes. The implications for sex differences in achievement and friendship are discussed.     

Reinforcement and punishment effects in concurrent schedules: A test of two models

The joint effects of punishment and reinforcement on the pigeon's key-peck response were examined in three choice experiments conducted to compare predictions of Farley and Fantino's (1978) subtractive model with those made by Deluty's (1976) and Deluty and Church's (1978) model of punishment. In Experiment 1, the addition of equal punishment schedules to both alternatives of a concurrent reinforcement schedule enhanced the preference exhibited for the more frequent reinforcement alternative. Experiment 2 demonstrated decreases in the absolute response rate for each member of a concurrent reinforcement schedule when increasing frequencies of punishment were added to each alternative. Experiment 3 found that preference for the denser of two reinforcement schedules diminished when the absolute frequencies of reinforcement were increased by a constant factor and conditions of punishment for both alternatives were held constant. Diminished preferences were obtained regardless of whether the frequency of punishment associated with the denser reinforcement schedule was greater or less than that associated with the lean reinforcement alternative. The results from all three experiments uniquely supported Farley and Fantino's (1978) subtractive model of punishment and reinforcement.     

The Ecological Veracity of the Self-Report

Sixty-five fourth- and fifth-grade boys were run in a two-choice discrimination learning task for punishment, high or low value reinforcement, or the combination of punishment with high or low value reinforcement. A significant main effect of reinforcement revealed that only Ss in the punishment group showed significant evidence of learning. The results were discussed as possibly being due to the distraction caused by tangible reinforcement; although, an alternative explanation was offered on the basis of previous findings that males perform better for punishment than for reward.     

Learning disability as related to infrequent punishment and limited participation in delay of reinforcement tasks

By comparing for learning disabled and control children parental frequency ratings of physical punishment and of completing household tasks, this experiment tested the hypothesis that parental indulgence is associated with learning disorders. Referral children with learning problems (N=18), matched on grade and sex with those in two control groups, were rated significantly lower on both measures than were either the students referred for other reasons or the nonreferred students. The infrequent punishment suggests that some children have learning problems because of a failure to acquire adequate response inhibition tendencies, which are necessary to control inappropriate behaviors resulting from the ineffective classroom positive reinforcement system. Furthermore, the lower responsibility index suggests some of their academic problems result from limited experiences functioning under delayed reinforcement.     

Male and female guppies differ in speed but not in accuracy in visual discrimination learning

In many species, males and females have different reproductive roles and/or differ in their ecological niche. Since in these cases the two sexes often face different cognitive challenges, selection may promote some degree of cognitive differentiation, an issue that has received relatively little attention so far. We investigated the existence of sex differences in visual discrimination learning in the guppy, Poecilia reticulata, a fish species in which females show complex mate choice based on male colour pattern. We tested males and females for their ability to learn a discrimination between two different shapes (experiment 1) and between two identical figures with a different orientation (experiment 2). In experiment 3, guppies were required to select an object of the odd colour in a group of five objects. Colours changed daily, and therefore, the solution for this task was facilitated by concept learning. We found males’ and females’ accuracy practically overlapped in the three experiments, suggesting that the two sexes have similar discrimination learning abilities. Yet, males showed faster decision time than females without any evident speed–accuracy trade-off. This result indicates the existence of consistent between-sex differences in decision speed perhaps due to impulsivity rather than speed in information processing. Our results align with previous literature, indicating that sex differences in cognitive abilities are the exception rather than the rule, while sex differences in cognitive style, i.e. the way in which an individual faces a cognitive task, are much more common.     

Interaction of reinforcement conditions and developmental level in a two-choice discrimination task with children

A total of 540 first, fourth, and eighth graders, equally divided by sex, were run on a two-choice discrimination task under one of three reinforcement conditions: reward (R) for correct responses, punishment (P) for incorrect responses, or reward and punishment (RP) for correct and incorrect responses. Half the Ss were tested by a male E; half, by a female E. Across all developmental levels, learning was superior in the P group. Complex interactions involving sex of S and E underline the importance of organismic variables in discrimination learning and in specifying parameters of reinforcer effectiveness.     

Immediate and delayed punishment of human behavior by loss of reinforcement

Young adult humans pressed a key to obtain money. When responding was punished by presentation of a stimulus signifying that money was lost, response frequencies decreased and response latencies increased. Since these changes did not increase relative earnings, the aversive properties of loss of reinforcement were manifested independently or reinforcement gain. When loss punishment was delayed for either 10, 20, or 40 sec the extent of suppression was found to vary inversely with the response-punishment interval. Subsequent manipulations indicated that the effectiveness of delayed punishment was increased when the response also produced immediate conditioned punishment, i.e., a stimulus paired with the delayed loss stimulus. Instructions about the response-punishment contingency had similar effects. The findings were consistent with animal studies of delayed shock punishment, insofar as a similar delay-of-punishment gradient was observed, and with studies of delayed positive reinforcement, insofar as mediation through conditioned punishment (or instructions) increased the effectiveness of delayed punishment.     

Sex differences in moral internalization and values.

The subjects were fifth- and seventh-grade white middle-class children and their parents. The major moral internalization indices pertain to internal moral judgment, guilt intensity, and fear of punishment. The findings support the prevalent view that consideration for others is more salient in females. They also suggest, with considerable consistency (especially in adults) that moral transgressions are more likely to be associated with guilt in females and fear in males. No sex differences in internal moral judgment were obtained. Evidence was presented suggesting that the differences in children may be due partly to different discipline and affection patterns. It was also suggested that the results for adults as well as children might be explained by differential sex-role socialization as well as by increasing pressures on males over the life cycle to achieve and succeed, which may often conflict with concerns about the welfare of others.     

Sex,race, and experiences of aggression

Most previous research on sex differences in experienced aggression has confounded the sex of the aggressor and of the target by considering married or dating couples. In the present study, black and white male and female college students were asked about specific acts of aggression which they had received from or directed toward a male or female. As predicted, males were likely to have both received and exhibited more forms of aggressive behavior, although females were somewhat more likely to have been honked at, to have been forced by a male to have sex, and to have slapped someone. Few racial differences were found, but it appeared that blacks might have been relatively more likely to exhibit physical aggression and whites to exhibit nonphysical aggression. Some differences were found in specific behaviors directed toward and received from males and females, but in general subjects said that they received more aggressive behaviors than they directed toward others. © 1992 Wiley-Liss, Inc.     

Sex differences in domain-specific depressogenic cognitive responses to negative and positive life events

Maladaptive cognitive responses to stressful life events represent well-replicated risk factors for depression. Research indicates that stressful life events that are dependent on the individual to occur or are interpersonal may generate more maladaptive cognitive responses than those that are independent and/or non-interpersonal. The current study examined the roles of sex and life event domains in eliciting depressogenic cognitive responses. Participants were 212 (71% female) undergraduate students who completed seven weekly questionnaires on participant-identified most negative and most positive life events over the previous 7 days. Additionally, participants reported levels of brooding and cognitive style in response to the most negative event and levels of positive rumination and dampening in response to the most positive event. Data were analyzed using mixed ANOVAs. Results indicated that females engaged in greater brooding regardless of event dependency. In addition, dependent and interpersonal life events generated greater brooding while dependent and non-interpersonal negative events generated greater negative cognitive style. An interaction between sex and domain was observed for dampening positive life events, such that males did not differ between interpersonal and non-interpersonal life events while females were more likely to dampen following interpersonal life events than non-interpersonal events.     

A TRANSACTIONAL ANALYSIS OF COMPLIANCE-GAINING BEHAVIOR

This study investigated how persuasive agents modify their compliance-gaining message strategy selection when they are confronted with noncompliant male and female persuasive targets in a variety of relational contexts. Based on instrumental learning theory, it was hypothesized that persuasive agents in noninterpersonal contexts would respond to noncompliant persuasive targets by increasing their preference for punishment-oriented message strategies and decreasing their preference for reward-oriented message strategies, whereas persuasive agents in interpersonal contexts would increase their preference for reward and punishment-oriented message strategies. Results confirmed the hypothesis. Moreover, males were expected to respond to noncompliant persuasive targets with more punishment-oriented strategies than females, and females were expected to use more rewarding strategies to secure compliance from noncompliant persuasive targets. However, results indicated that females responded to noncompliant persuasive targets with more punishment and reward-oriented strategies than males. Results also showed that the effects of persuasive agents' gender on message selection is mediated by the gender of persuasive targets and the duration of the relational consequences.     

Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior

Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior were examined in a large community sample of 6,383 adult male, female, and opposite-sex twins. Retrospective reports of childhood conduct disorder (prior to 18 years of age) were obtained when participants were approximately 30 years old, and lifetime reports of adult antisocial behavior (antisocial behavior after 17 years of age) were obtained 8 years later. Results revealed that either the genetic or the shared environmental factors influencing childhood conduct disorder differed for males and females (i.e., a qualitative sex difference), but by adulthood, these sex-specific influences on antisocial behavior were no longer apparent. Further, genetic and environmental influences accounted for proportionally the same amount of variance in antisocial behavior for males and females in childhood and adulthood (i.e., there were no quantitative sex differences). Additionally, the stability of antisocial behavior from childhood to adulthood was slightly greater for males than females. Though familial factors accounted for more of the stability of antisocial behavior for males than females, genetic factors accounted for the majority of the covariation between childhood conduct disorder and adult antisocial behavior for both sexes. The genetic influences on adult antisocial behavior overlapped completely with the genetic influences on childhood conduct disorder for both males and females. Implications for future twin and molecular genetic studies are discussed.     

Factors Affecting the Psychodiagnostic Significance of Color Perception

50 males, 17 and 18 years of age, and their natural parents were given the Blacky Defense Preference Inventory to determine if there are commonalities of defense preferences within families and within sex groups.

The results tended to support the hypothesis that male adolescents manifest defense preferences more similar to those of their father than to nonrelated adult males but failed to support a comparable hypothesis concerning the adolescent's similarity of defense preferences to his mother versus nonrelated adult females. The adolescent males did not reveal defense preferences more similar to those of their father than of their mother nor were sex differences in defense preferences observed. An additional finding suggested that the adult males are more heterogeneous in their defense preferences than are adult females.     

A comparison of adult women's and men's ascriptions of negative traits to the same and opposite sex

College students (N=135), ranging from 19 to 55 years of age, were studied to determine their sex stereotypes. Results from the present study indicated that adult males were significantly more negative than adult females in their evaluations of both sexes. One possible explanation that may be offered to account for these findings is that current emphasis of female rights may be causing negativistic reactions on the part of males toward both sex groups.     

Sex differences in the neural underpinnings of social and monetary incentive processing during adolescence

The brain’s reward system undergoes major changes during adolescence, and an increased reactivity to social and nonsocial incentives has been described as a typical feature during this transitional period. Little is known whether there are sex differences in the brain’s responsiveness to social or monetary incentives during adolescence. The aim of this event-related potential (ERP) study was to compare the neurophysiological underpinnings of monetary and social incentive processing in adolescent boys versus girls. During ERP recording, 38 adolescents (21 females, 17 males; 13–18 years) completed an incentive delay task comprising (a) a reward versus punishment condition and (b) social versus monetary incentives. The stimulus-preceding negativity (SPN) was recorded during anticipation of reward and punishment, and the feedback P3 (fP3) along with the feedback-related negativity (FRN) after reward/punishment delivery. During anticipation of social punishment, adolescent boys compared with girls exhibited a reduced SPN. After delivery, male adolescents exhibited higher fP3 amplitudes to monetary compared with social incentives, whereas fP3 amplitudes in girls were comparable across incentive types. Moreover, whereas in boys fP3 responses were higher in rewards than in punishment trials, no such difference was evident in girls. The results indicate that adolescent boys show a reduced neural responsivity in the prospect of social punishment. Moreover, the findings imply that, once the incentive is obtained, adolescent boys attribute a relatively enhanced motivational significance to monetary incentives and show a relative hyposensitivity to punishment. The findings might contribute to our understanding of sex-specific vulnerabilities to problem behaviors related to incentive processing during adolescence.     

Evaluation and reinforcement: What do males and females really want to hear?

This research was designed to note if males and females differ in their choices of the reinforcement and evaluation they assign to others. Thirty-one male and 31 female subjects viewed four videotapes of skilled and unskilled male and female speakers. Subjects assigned 10 of 40 statements varying in reinforcement value to each speaker and completed a five-item evaluation for each speech. Participants also completed a four-item measure to determine if they selected comments that they too would want to receive. Results indicated that males desire more positive reinforcement than females, although the two genders do not differ in their selection of evaluation. Also, subjects agreed that statements they selected were those they would find acceptable if applied to them.     

Enlargement of Neuronal Somata in the LMAN Coincides with the Onset of Sensorimotor Learning for Song

The lateral magnocellular nucleus of the anterior neostriatum (LMAN) in the zebra finch (Taeniopygia guttata) has been shown to play a developmentally restricted role that is essential during song-learning processes. Dendritic spine frequencies and synapse numbers in LMAN have been reported to decline in males during early vocal motor learning and thereafter, but not in females, who do not sing. Nissl staining has shown the LMAN volume to be very similar in both sexes, however. To gain more insight into the development of sex-specific differences in LMAN, the size of neuronal somata and cell nuclei were analyzed in 1-μm semithin sections. Cell somata and nuclei were similar in males and females during the initial phases of sensory memory formation for song, but during early vocal motor learning cell size increased in males and decreased in females. Sex differences in neuronal somata size were present at 50 days and remained throughout life. This sex difference may be indicative of a difference in protein biosynthesis in LMAN, arising as a consequence of vocal learning in males.     

Attitudes in four age groups toward sex role division in adult occupations and activities

Kindergarten, eighth grade, college, and adult subjects were presented with a list of 43 adult occupations. They indicated for each whether it should be performed by a male, female, or either. Liberality, defined in terms of the number of “either” responses, increased markedly from kindergarten to eighth grade through college and then showed a moderate decrease in the adult sample. In each age group except kindergarten there was a significant sex difference with females being more liberal. Analysis of individual roles showed that both sexes were willing to let women into prestige occupations but females were more willing than males to have household and child-caring tasks performed by both sexes.     

DEVELOPMENTAL SEX DIFFERENCES IN THE RELATION OF NEUROANATOMICAL CONNECTIVITY TO INTELLIGENCE

Recent neuroimaging research has shown sex-related differences in the relationship between brain structure and cognitive function. Anatomical studies have shown a greater reliance for cognitive function on white matter structure in adult females, and a greater reliance on gray matter structure in adult males. Functional neuroimaging studies have also shown a greater correlation between brain connectivity and cognitive function in females. However, this relationship is not present in young childhood (5 years old) but appears during the developmental period. Here sex differences in structure–function relationships and their developmental trajectory are investigated using diffusion tensor imaging (DTI) on a large cohort of over 100 normal children ages 5–18. Significant sex–X–IQ interactions on fractional anisotropy (FA), a marker for white matter organization, were seen in the left frontal lobe, in fronto-parietal areas bilaterally, and in the arcuate fasciculus bilaterally, with girls showing positive correlations of FA with IQ, and boys showing a negative correlation. Significant sex–X–IQ–X–age interactions on FA were also seen in the left frontal lobe and in fronto-parietal areas bilaterally, showing a developmental effect. These results strongly corroborate previous findings regarding sex differences in structure–function relationships regarding intelligence. Results also indicate that a naïve interpretation of “more is better” with respect to FA may not be accurate, especially in adult males.