Single leg landing movement differences between male and female badminton players after overhead stroke in the backhand-side court

Females showed higher anterior cruciate ligament (ACL) injuries rate on the opposite side of dominant hand compared with males during single leg landing in the backhand-side court after overhead stroke. The purpose of this study was to conduct biomechanics testing including kinematics and kinetics to provide some insights on the ACL injuries risks during single leg landing in the backhand-side court after overhead stroke between females and males. Twenty collegiate badminton players (10 females, 10 males) voluntarily participated in this study. Sagittal plane kinematic and kinetic data of the lower limb, and their ground reaction forces during the single leg landing in the backhand-side court after overhead stroke were collected. Results shown that, at the peak posterior ground reaction force (GRF) moment, the ankle dorsiflexion, knee and hip flexion angles of the female were lower than that of male. Meantime, the knee extension moment of the female was lower than that of males but the hip extension moment of the female was larger compared to males at the peak posterior GRF moment. The peak vertical and posterior GRF of female badminton players were larger than that of males. Decreased hip, knee, and ankle flexion angles at the peak posterior GRF moment and greater peak vertical and posterior GRF may expose female badminton players to the higher risk ACL injuries compared to males during single leg landing after overhead stroke in the backcourt-side. Preventative training programs designed to prevent the ACL injuries rate of female badminton players should take these factors into consideration.     

Electrodermal orienting responses to verbal and geometrical visual stimuli projected to the left or right retinal half-fields: sex differences

Using the visual half-field technique, verbal and geometrical slides were repeatedly projected to either the left or right visual field in an electrodermal orienting paradigm. Bilateral skin conductance response-magnitudes were recorded continuously over trials. Half the subjects (8 males and 8 females) had a verbal and a geometrical slide repeatedly presented to the right of a central fixation-point, (i.e. initial left hemisphere input) and the other half had the same kinds of stimuli presented to the left (i.e. initial right hemisphere input). There were 32 presentations of each stimulus, i.e. a total of 64 trials. The intertrial interval (ITI) varied between 25 to 40 sec. Results showed significantly larger response-magnitudes in the female group having the stimuli presented in the left visual field and especially to the geometrical slide. The same trend in data was also found for the male subgroup having the stimuli presented in the left visual field. No significant differences between the bilateral left and right hand recordings were foundin the main analysis. However, a closer inspection of the data indicated the left hand recording to be more sensitive than the right hand recording.     

Hypothalamo-pituitary-adrenocortical axis function and hedonic behavior in adult male and female rats prenatally stressed by maternal food restriction

Neuroendocrine activation during stress is affected by many factors contributing to the variability of the stress response. The present study was aimed at evaluating long-term changes in hypothalamo-pituitary-adrenocortical (HPA) axis function and in hedonic behavior in adult offspring prenatally stressed by maternal food restriction, with attention on possible gender differences. Adult offspring were blood sampled via a tail artery cannula. Prenatally stressed females had significantly higher adrenal weights compared to males. Plasma ACTH levels, which rose in response to acute stress induced by handling, were significantly higher in females compared to those in males. A similar pattern was found in plasma corticosterone. The rise in ACTH levels was more pronounced in prenatally stressed rats though the rise in corticosterone failed to be modified. Corticotropin releasing hormone (CRH) and proopiomelanocortin mRNA levels in the hypothalamic paraventricular nucleus and anterior pituitary, respectively, were found to be unchanged. The present experiments failed to reveal a decrease in hedonic behavior in prenatally stressed rats. In contrast, in male offspring a tendency to a higher sucrose preference was observed. These data together with observed changes in hormone and CRH mRNA levels indicate that the gestational stress used did not result in a depression-like state in adult offspring.     

Contribution of Callosal Connections to the Interhemispheric Integration of Visuomotor and Cognitive Processes

In recent years, cognitive neuroscience has been concerned with the role of the corpus callosum and interhemispheric communication for lower-level processes and higher-order cognitive functions. There is empirical evidence that not only callosal disconnection but also subtle degradation of the corpus callosum can influence the transfer of information and integration between the hemispheres. The reviewed studies on patients with callosal degradation with and without disconnection indicate a dissociation of callosal functions: while anterior callosal regions were associated with interhemispheric inhibition in situations of semantic (Stroop) and visuospatial (hierarchical letters) competition, posterior callosal areas were associated with interhemispheric facilitation from redundant information at visuomotor and cognitive levels. Together, the reviewed research on selective cognitive functions provides evidence that the corpus callosum contributes to the integration of perception and action within a subcortico-cortical network promoting a unified experience of the way we perceive the visual world and prepare our actions.     

Neutralization and delinquency: a comparison by sex and ethnicity

A path model illustrating the relationships between church attendance, delinquent peer association, tendency to neutralize delinquency, and self-reported delinquent behavior was compared between males and females and between Mexican-American and Anglo college students (N = 694). The structure of the relationships among these variables was found to be similar across all four subsamples, although there was some variation in the strength of the relationships. In all four subsamples, the strongest paths were between neutralization and delinquent behavior, especially among Anglos and among males, and the weakest paths were between church attendance and delinquent behavior. On the other hand, church attendance was more strongly related to having fewer delinquent peers among Anglos and females. The path models explained substantial amounts of variation in delinquent behavior: 38% among Anglos, 32% among females, 31% among males, and 30% among Mexican-Americans.     

Effects of selective breeding for high and low aggressiveness and of fighting experience on odor discrimination in mice

The present study was designed to determine whether male and female mice, selectively bred for high (TA) and low (TNA) aggressiveness, react in different ways when exposed to odors from males of the same strains. The effects of losing or winning fights on odor preferences in the TA males were also studied. The low aggressive TNA males were found to avoid areas soiled by the highly aggressive TA males. The TA males, on the other hand, were most interested in the areas soiled by other highly aggressive TA males. Along with decreasing aggressiveness, losing fights radically changed the odor preferences of the TA males, the soiled bedding from winner TA males now having a strong aversive effect. TNA females preferred the odors of TA males, while the TA females preferred the odors of TNA males. The genotype of the receiver of odor cues is important for the preference choices; this effect can, however, be changed through experience.     

Distinguishing Between Subgroups of Adolescents Who Self‐Harm

The differences in factors associated with subgroups of adolescents in the continuum of deliberate self‐harm (DSH) phenomena were investigated. In an anonymous self‐report survey of 6,020 adolescents aged 15 and 16 years, 3.2% of adolescents (5.3% females, 1.3% males) reported DSH with intent to die, 2.8% (4.3% females; 1.5% males) reported DSH without intent to die, and 15% (22.4% females; 8.5% males) reported thoughts of DSH without acts. Regression analysis indicated considerable overlap in vulnerability factors along the spectrum of DSH thoughts and acts. A uniquely distinct relationship was found between DSH of a friend and DSH without intent to die on one hand and DSH of a family member with DSH with intent to die on the other. Results indicate that familial and nonfamilial social influences on DSH behavior may be important in designing prevention programs and that educational programs for the promotion of psychological well‐being may be helpful for adolescents at any point along the spectrum of DSH that was examined.     

The effects of feedback on the gender differences in the performance in a chronometric mental-rotation test

ABSTRACT

Gender differences favouring males are often found in mental-rotation tests and are usually smaller in chronometric than in psychometric test. The individual feedback in the chronometric test could be an explanation for the comparable performance of males and females. To test this hypothesis, 102 undergraduate students (60 females, 42 males) participated in a chronometric mental-rotation study with or without feedback. A subsample of 41 participants was asked to report their confidence about their performance in the test. In reaction time, males outperformed females and participants in the feedback condition reacted faster than participants without feedback. A significant interaction of gender and condition was found. Only females had an advantage in the feedback condition in reaction time while there was no difference for males. Males reported higher scores of confidence. Feedback seemed to help females especially to react faster. Confidence levels are discussed as reasons for differences between conditions and genders.     

Sex role orientation and dimensions of self-esteem among middle adolescents

A questionnaire study of 229 high-school students examined the relationship between sex role orientation and various dimensions of self-esteem. The results provide strong support for the masculinity model self-esteem, especially for females. Multivariate analyses of variance revealed the following: (a) females perceived themselves to be significantly more socially competent than males; (b) males perceived themselves to be more physically competent than females; (c) adolescents high on masculinity perceived themselves to be significantly more socially competent, physically competent, and to have higher general self-esteem than those low on masculinity; (d) males and females high on masculinity perceived themselves to be significantly more physically competent and to have higher general self-esteem than females low on masculinity, although males low on masculinity did not differ significantly from any of the other interaction groups. Regression analyses by gender revealed the following: (a) the contribution of masculinity to social competence was much greater for females than for males, (b) the contribution of masculinity to physical competence was much greater for females than for males, and (c) the contribution of masculinity to general self-esteem was much greater for females than for males. In summary, for males, gender may override the impact of sex role orientation, while among females the impact of sex role orientation may be accentuated.     

Nature and facts about natural and artifactual categories: Sex differences in the semantic priming paradigm

There is abundant evidence from behavioral and neurophysiological experiments for the distinction of natural versus artifactual categories and a gender-specific difference: women’s performances in cognitive tasks increase when natural categories are used, whereas men’s performances increase with artifactual categories. Here, we used the semantic priming paradigm to study retrieval processes by presenting category labels as primes and exemplars as targets. Overall, in two experiments we found larger priming effects for natural than for artifactual categories. In addition, females showed positive priming effects for natural but negative effects for artifactual categories, whereas males showed positive priming effects for both categories. This pattern matches with that from other tasks and can be interpreted as evidence that the findings from these other tasks are, at least partially, indeed due to different representations or processing modes for males and females and not (exclusively) due to—for example—different familiarity with a category. In a further experiment, we showed that the found pattern for females can be manipulated by focusing on perceptual vs. functional features. The results can be interpreted as first evidence that there are (eventually in addition to different “crystallized” semantic structures) specific default processing modes that differ for males and females.     

Effect of target animacy on hand preference in Sichuan snub-nosed monkeys (<Emphasis Type="Italic">Rhinopithecus roxellana</Emphasis>)

Twenty-eight captive Sichuan snub-nosed monkeys (Rhinopithecus roxellana) were involved in the current study. Many individuals showed handedness, with a modest tendency toward left-hand use especially for animate targets, although no group-level handedness was found. There was no significant gender difference in the direction and strength of hand preference for both targets. Females showed a significantly higher overall rate of actions toward animate targets than inanimate targets for both hands, whereas males displayed almost the reversed pattern. There were no significant interactions between lateral hand use and target animacy for either males or females. Most individuals showed rightward or leftward laterality shift trends between inanimate and animate targets. These findings to some extent support the existence of a potential trend concerning a categorical neural distinction between targets demanding functional manipulation (inanimate objects) and those demanding social manipulation (animate objects), even though specialized hand preference based on target animacy has not been fully established in this arboreal Old World monkey species.     

Monaural recall and the right-ear advantage

Lists of eight nonsense syllables were monaurally presented to right-handed men and women for free recall, half to each ear on each trial. Results showed a right-ear advantage (REA) in the recall of recency items, but not primacy items and for males only. Among males only that subgroup without familial sinistrality demonstrated the REA. Results offer support for the following: (A) the language mechanisms involved in short-term “echoic” memory are particularly well-lateralized; (B) mechanisms underlying monaural REAs may be similar to those responsible for the asymmetries found in other paradigms; (C) processing demands and strategies inherent to the monaural technique may account in part for its limited reliability in yielding REA and for the present absence of REA among females.     

Position of the non-stance leg during the single leg squat affects females and males differently

BackgroundKinematic differences between females and males for the single leg squat (SLS) have been identified. However, kinetic differences between sexes and how variations of the non-stance leg position during the SLS may affect kinematics and kinetics differently in females and males have not been examined.ObjectivesExamine sex-specific kinematic and kinetic differences during the SLS task with 3 different non-stance leg positions.DesignControlled laboratory study, cross-sectional design.MethodsThirty-two healthy adults (16 females, 16 males) performed the 3 SLS tasks while data were collected using a motion capture system and force plates. At 60 degrees of knee flexion (60KF) and peak knee flexion (PKF), kinematics and joint moments were compared between sexes and SLS tasks using a linear regression analysis.ResultsFemales exhibited less ipsilateral trunk flexion (P < 0.001) and greater anterior pelvic tilt (P ≤ 0.021) and hip adduction (P < 0.001) than males across tasks at 60KF and PKF. Across tasks, females had a smaller knee flexion moment than males at PKF (P = 0.001). Females had a greater hip abduction moment during SLS-Front than SLS-Middle (P = 0.044) and SLS-Back (P = 0.003) at PKF, but males had similar hip abduction moments across tasks (P ≥ 0.299). At 60KF, males had a greater knee adduction moment during SLS-Front compared to the other tasks (P ≤ 0.019) while females had similar hip abduction moments across tasks (P ≥ 0.459).ConclusionAltering the non-stance leg position during the SLS affects the kinematics and kinetics of both females and males. The position of the non-stance leg can be modified for assessment and treatment purposes and should be reported in research.     

Sex differences in prenatally programmed anxiety behaviour in rats: differential corticotropin-releasing hormone receptor mRNA expression in the amygdaloid complex

We recently reported that male, but not female, offspring born to mothers exposed to social stress during late gestation show heightened anxiety-type behaviour in adulthood. The amygdala organises anxious behaviour, which involves actions of corticotropin-releasing hormone (CRH). CRH gene expression and/or its release are increased in the amygdala in prenatally stressed (PNS) rats. CRH type 1 receptor (CRH-R1) mediates actions of CRH and urocortin I to promote anxiety-like behaviour, whereas the CRH type 2 receptor (CRH-R2) may mediate anxiolytic actions, through actions of urocortins 2 and 3. Here, using quantitative in situ hybridisation, we investigated whether altered CRH receptor mRNA expression in the amygdaloid nuclei may explain the sex differences in anxiety behaviour in adult male and female PNS rats. CRH-R1 mRNA expression was significantly greater in the central amygdala and basolateral amygdala (BLA) in male PNS rats compared with controls, with no change in the basomedial amygdala (BMA) or medial amygdala (MeA). In PNS females, CRH-R1 mRNA expression was greater than controls only in the MeA. Conversely, CRH-R2 mRNA expression was significantly lower in the BMA of male PNS rats compared with controls, but greater in female PNS rats, with no change in the BLA or MeA in either sex. The ratio of CRH-R1:CRH-R2 mRNA in the amygdaloid nuclei was generally increased in PNS males, but not in the PNS females. In conclusion, sex differences in anxiety-type behaviour in PNS rats may be explained by differential mRNA expression for CRH-R1 (pro-anxiogenic) and CRH-R2 (pro-anxiolytic) in the amygdaloid complex.     

Size does matter: Women mentally rotate large objects faster than men

Performance in a computerized “mental rotation” task was measured in groups of males and females while they rotated Shepard‐Metzler‐like cube assemblies on either a standard laptop screen (size = 36 cm) or on a large display wall (584 cm) where the stimuli appeared at considerably larger sizes and within a much wider field of view than that typically used in most spatial tasks. Males and females did not differ significantly in performance in the standard size condition with regards to response time but females performed faster than males in the large display condition. Males were also found to be significantly more accurate than females, regardless of display. We found no sign of trading accuracy for speed for either of the sexes or screen size conditions. We surmise that such an effect may be due to differences in task‐solving strategies between the sexes, where a holistic strategy – which may be preferred by males is negatively affected by large object sizes, whereas a piecemeal approach, that may be preferred by females, is virtually unaffected by display size.     

Effects of neonatal treatment with 1-(2,5-dimethoxy-4-lodophenyl)-2 aminopropane HCI (DOI) and ritanserin on agonistic behavior in adult male and female rats

The role played by the neonatal 5-hydroxytryptamine (5HT) system in the organization and sexual differentiation of adult agonistic behavior was investigated in rats. Focus was on the 5HT2 receptor subtype, which has been demonstrated to be involved in agonism control in the adult. 5HT2 activity was experimentally manipulated by administration of a specific agonist [1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane HCl (DOI)] or antagonist (ritanserin) during the second week of life, when serotonin is known to concur to anatomical and behavioral sexual differentiation. Interactions between early 5HT2 activity, genetic sex, and neonatal circulating testosterone (T) were studied by administering the ligands to males, females, and androgenized females. At adulthood, the animals were tested for both aspects of agonism, i. e., aggression and defense, in a 20-min confrontation with an unfamiliar conspecific of the same sex, age, body weight, and social experience. Neonatal administration of the 5HT2 antagonist ritanserin increased aggression independently of sex; it also increased defense, but this effect was confined to males. The agonist DOI had no effect on aggression, but enhanced defense in males and androgenized females, with an effect which depended therefore more on neonatal T than genetic sex. Females appeared in general less sensitive to neonatal 5HT2 manipulation than both androgenized females and males; this suggests that neonatal T is crucial for experimental modifications of neonatal 5HT2 activity to have any consistent effect on adult agonistic behavior. On the other hand, effects observed in males and androgenized females were dependent on the behavior considered and the drug administered. This was especially evident for defense, enhanced by ritanserin in males only, and in both males and androgenized females by DOI. Neonatal 5HT2 activity seems therefore to play a role in the modulation of adult agonistic behaviors, which depends on the behavior considered and is under multiple control of genetic sex and hormonal neonatal substrate. © 1994 Wiley-Liss, Inc.     

On the relationship between coding and the ability to see what one is doing in a sensori-motor task

In order to examine the possible interaction between different display-control relationships and the ability to look at what one is doing an experiment was carried out under four conditions: half the subjects were trained with a colour code display, the other half with a positional code; within each of these groups half the subjects were allowed to look at their hand while performing, and the others were not. It was found that the effect of not being allowed to look was larger with the colour code in the initial phase of training, and larger with the positional code in the final phase of training.     

Development of unimanual versus bimanual task performance in an isometric task

Sixty-three children between 5 and 12 years of age and 15 adults performed a unimanual and a bimanual isometric force task. The performance of the preferred hand in the unimanual task was compared to the performance of the preferred hand in the bimanual task. It was hypothesized that in the bimanual task the absolute error will be higher, there will be more irregularity and the participants will need more time due to the additional effort from the central nervous system, especially with respect to the communication between the hemispheres. Furthermore, in younger children bimanual force variability was expected to be higher due to developmental aspects concerning callosal maturation and attention. It was found that with respect to force generation the preferred hand was not affected by bilateral isometric force generation, but with respect to force regulation it was. The coefficient of variation (CV) of the force was 34% larger in the bimanual task as compared to the unimanual task. For the time to target force, the increase was 28%. With repetition of the trials the CV decreased in the bimanual task, but only in the youngest age group. During development there was no change in absolute error, yet there was a major reduction in force variability in the bimanual task. It is suggested that improvement in interhemispheric communication and in the ability to focus attention plays a role in the decrease in variability with age.     

Sex differences in the generalization of attraction

The effects of intergroup evaluations on intragroup attraction were assessed in a situation involving two-person teams that were all of the same sex. Male (N=123) and female (N=118) group members separately reported their political views to another dyad and then received either unfavorable, favorable, or no feedback regarding their team as a whole on the basis of this information. The results indicated that females evidenced more anger in response to the out-group's unfavorable feedback than did males. These anger responses were related to attraction to ward a teammate for males but not for females. Moreover, males evidenced less attraction toward an in-group member after receiving unfavorable rather than favorable intergroup evaluations, whereas females did not. On the other hand, only for females was attraction to ward a teammate related to the perceived similarity of that individual within experimental conditions. Apparently, the greater cognitive orientation of females as compared to males to ward another ingroup member resulted in their being less susceptable to the influence of situationally induced affect.This research was performed as part of the author's doctoral dissertation submitted to the Department of Psychology, Purdue University. Portions of this paper were presented at the meeting of the Eastern Psychological Association held in Boston, 1977.It should be noted that the views expressed in this paper are those of the author and do not reflect those of the Army or any other government agency.     

A test of the Zucherman heterosexual scales

Summary: Female and male undergraduate students enrolled in the introductory psychology course were administered the Zuckerman heterosexual scale as part of a larger battery of tests. The ordering of items for males was very similar to Zuckerman's with two minor exceptions. Female subjects, on the other hand, reported more sexual experiences of all kinds than did Zuckerman's sample, and two major differences in ordering Were noted. The coefficients of reproducibility for males and females were .928 and .954 respectively which were almost identical to those of Zuckerman. The rank-order correlation between the ranking of the items in the male and female scales was .958.