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1.
Assume an X-linked gene in two alleles mediates performance on field dependent-independent tests such as the rod-and-frame test. Only the recessive gene with relative frequency q facilitates field independence. Other genotypes lead to field dependence. Under a simple genetic model, field dependence-independence may be viewed as outcomes of a discrete random variable B with field independent and dependent probabilities πiq and 1 ? πiq for men, and πiq2 and 1 ? πiq2 for women, respectively. The parameter πi is a maturational ageindexed parameter, 0 < πi ≤ 1, monotonically increasing with development until maturity when πk = 1. Observations of performance are made on a random variable W of the form W = B + N, where N is normal in distribution independent of B; N represents a composite of influences including error. The model implies testable age-related between- and within-sex predictions regarding E(W) and Var(W), predictions which appear to coincide with major empirical findings; it also generates novel predictions. For instance, W is a mixture of normals distribution. The model is briefly evaluates in two data sets.  相似文献   

2.
The pendular mechanism does not act as a primary mechanism in uphill walking due to the monotonic behavior of the mechanical energies of the center of mass. Nevertheless, recent evidence shows that there is an important minimization of energy expenditure by the pendular mechanism during walking on uphill gradients. In this study, we analyzed the optimum speed (OPT) of loaded human walking and the pendulum-like determining variables (Recovery R, Instantaneous pendular re-conversion Rint, and Congruity percentage %Cong). Ten young men walked on a treadmill at five different speeds and at three different treadmill incline gradients (0, +7 and +15%), with and without a load carried in their backpacks. We used indirect calorimetry and 3D motion analysis, and all of the data were analyzed by computational algorithms. Rint increased at higher speeds and decreased with increasing gradient. R and %Cong decreased with increasing gradient and increased with speed, independent of load. Thus, energy conversion by the pendular mechanism during walking on a 15% gradient is supported, and although this mechanism can explain the maintenance of OPT at low walking speeds, the pendular mechanism does not fully explain the energy minimization at higher speeds.  相似文献   

3.
The purpose of this study was to use polynomial regression analyses to examine the torque- and power-velocity relationships and calculate and compare the vertices of these nonlinear models, and how they relate to measurements of muscle size and maximal strength, between male and female children and adolescents during maximal isokinetic leg extension muscle actions. Sixteen children (n = 8 males, n = 8 females) and 22 adolescents (n = 11 males, n = 11 females) participated in this study. Measurements of growth included age, maturity offset, height, body mass, fat-free mass, and quadriceps femoris muscle cross-sectional area (CSA). Participants completed maximal voluntary isometric contractions (MVICs) of the leg extensors and maximal voluntary isokinetic leg extensions at 60, 120, 180, 240, and 300°·s−1. Variables calculated during all leg extension muscle actions included peak torque (PT, Nm) and mean power (MP, W). Polynomial regression analyses determined the model of best fit for the PT- and MP-velocity relationships. For each participant, the vertex from the PT- and MP-velocity quadratic models were quantified as the predicted maximum velocity of last measurable torque (VPT) and the predicted velocity of maximum mean power (VMP), respectively. Measurements of growth, PT and MP at all velocities, VPT, and VMP were greater in the adolescents than children. When normalized to CSA, VPT and VMP remained greater for adolescents than children, and exhibited low to very high relationships with measurements of growth. When normalized to MVIC strength, VPT and VMP were no longer different between children and adolescents and exhibited negligible to low relationships with measurements of growth. The results of the present study suggest that the ability to produce torque and power at high velocities may be more dependent on muscle strength than muscle size, which suggests that mechanisms other than muscular hypertrophy affect torque and power production at high velocities in young males and females.  相似文献   

4.
We investigated the effect of handedness and sex on: (i) sulcal contours defining PO and PTR and (ii) volume estimates of PO and PTR subfields in 40 left- and 42 right-handers. Results show an effect of handedness on discontinuity of the inferior frontal sulcus (IFS: < 0.01). Discontinuity of IFS was observed in: 43% left- and 62% right hemispheres in right-handers and in 65% left- and 48% right-hemispheres in left-handers. PO volume asymmetry was rightward in left-handed males (= 0.007) and females (= 0.02), showed a leftward trend in right-handed males (= 0.06), and was non-asymmetrical in right-handed females (= 0.96, i.e. left- and right-hemisphere PO volumes did not differ significantly). PO volume asymmetry in males differed significantly between handedness groups (= 0.001). Findings indicate a high degree of variability in the sulcal contours of PO and PTR and volume asymmetry of PO: the factors sex and handedness can explain some of this variability.  相似文献   

5.
6.
Escape and avoidance behaviors play a prominent role in the maintenance and possibly development of panic disorder, yet the literature regarding the etiology of these emotion-regulation strategies is relatively underdeveloped. The current study experimentally tests hypotheses that parental modeling of escape during a well-established panic-relevant biological challenge increases panic-relevant escape and avoidance among offspring. Fifty physically and psychologically healthy early adolescents (28 females; Mage = 11.58; 86% Caucasian), stratified by gender, were randomly assigned to observe one of their parents (39 females; Mage = 40.04): either (a) model completing a 3-min voluntary hyperventilation exercise (no escape modeling group) or (b) model premature termination of a similar procedure (escape modeling group). Offspring in the escape modeling group demonstrated a stronger escape response by discontinuing their own challenge sooner than those in the no-escape modeling group (r = .70). No group differences emerged in terms of avoidance responding, as indexed by nearly identical responding in terms of delay time before initiating the challenge, respiration rate, and self-reported willingness to engage in a second proposed challenge. Results suggest that parental behaviors may play an important role in the development of some forms of panic-relevant responding. These preliminary findings may have important implications for future prevention programs targeting parents and at-risk youth.  相似文献   

7.
In Experiment 1, rats were trained on a discrimination in which one occasion setter, A, signaled that one cue (conditioned stimulus, CS), x, would be followed by one outcome, p (unconditioned stimulus, US), and a second CS, y, by a different outcome, q (x → p and y → q); a second occasion setter, B signalled the reverse CS-outcome relations (x → q and y → p). In a subsequent stage, the animals were divided into two groups, and trained as before, except that both A and B were presented in compound with a novel occasion setter, C. For Group S (same) the CS-outcome relations following A and B were identical to those in the pretraining stage, whereas in Group D (different) they were reversed. In a subsequent test, stimulus C was shown to be a more effective occasion setter in Group D than in Group S. In Experiment 2, rats were trained on a negative occasion-setting discrimination in which CS x signaled outcome p, and y outcome q; when x and y were signaled by the occasion setter A then no outcome followed (x → p, y → q, A:x-, and A:y-). In a subsequent stage, A was now trained as a positive occasion setter, signaling reinforcement of x and y. In Group S, x and y signaled the same outcomes as in the prior training stage (x-, y-, A:x → p, and A:y → q), whereas in Group D they signaled the opposite outcomes (x, y, A:x → q, and A:y → p); more efficient test performance was seen in the latter group. These results suggest that the each occasion setter conveyed information about the specific combination of CS and US paired in its presence (i.e., x → p and y → q, or x → no p and y → no q). These results are consistent with the suggestion that occasion setters operate, at least in part, on a specific CS-US association.  相似文献   

8.
《Behavior Therapy》2022,53(3):469-480
Post-9/11 U.S. veterans are clinically complex with multiple co-occurring health conditions that lead to increased morbidity and mortality, risk for suicide, and decreased quality of life, but underutilization and resistance to treatment remain significant problems. Increased isolation and decreased community and social support due to coronavirus disease (COVID-19) have exacerbated mental health risk. This study evaluated the safety and feasibility of home-based telemental health group workshops to improve reintegration and social connection in post-9/11 U.S. military personnel. Seventy-four (61 males/13 females) post-9/11 U.S. military veterans were randomized to receive 12 sessions of STEP-Home cognitive-behavioral group workshop or present-centered group therapy. Treatment was delivered either in person (traditional medical center setting, treatment as usual [TAU]), or via home-based synchronous videoconferencing (VC). The change to VC occurred due to social distancing guidelines during COVID-19. Mean age was 41.0 years (SD = 11.5, range 24–65). Forty-five (36 males/9 females) participated in VC and 29 (25 males/4 females) in TAU. Demographics were similar across treatment milieu. There were no differences in therapist treatment adherence for TAU versus VC. Therapist satisfaction was higher for TAU groups (q value < .05). Veterans showed higher enrollment, attendance, group cohesion, and veteran-to-veteran support for VC compared to TAU (q values < .05). Safety procedures were successfully implemented via VC. Results demonstrate the safety, feasibility, and high satisfaction of group telemental health in U.S. veterans. Higher enrollment and treatment adherence for telemental health delivery resulted in a greater likelihood of receiving an effective treatment dose than TAU. Strong group cohesion and veteran-to-veteran support were achievable via telehealth. Telemental health offers convenient, efficient, and cost-effective care options for veterans and may be particularly helpful for patients with high psychiatric burden.  相似文献   

9.
Data from three experiments on serial perception of temporal intervals in the supra-second domain are reported. Sequences of short acoustic signals (“pips”) separated by periods of silence were presented to the observers. Two types of time series, geometric or alternating, were used, where the modulus 1 + δ of the inter-pip series and the base duration Tb (range from 1.1 to 6 s) were varied as independent parameters. The observers had to judge whether the series were accelerating, decelerating, or uniform (3 paradigm), or to distinguish regular from irregular sequences (2 paradigm). “Intervals of subjective uniformity” (isus) were obtained by fitting Gaussian psychometric functions to individual subjects' responses. Progression towards longer base durations (Tb = 4.4 or 6 s) shifts the isus towards negative δs, i.e., accelerating series. This finding is compatible with the phenomenon of “subjective shortening” of past temporal intervals, which is naturally accounted for by the lossy integration model of internal time representation. The opposite effect observed for short durations (Tb = 1.1 or 1.5 s) remains unexplained by the lossy integration model, and presents a challenge for further research.  相似文献   

10.
This study investigates body esteem factors (weight-esteem and appearance-esteem) as mediators of the relationship between ‘internalization of the ideal body figure’ and disordered eating behaviors (restrained, emotional and external eating) in a community sample of adolescent males (n = 810) and females (n = 1137) from the Ontario Research on Eating and Adolescent Lifestyles (REAL) study. Mediation models were examined using a bootstrapping approach to test indirect effects and indirect contrasts. In males, weight-esteem partially mediated the relationship between muscular ideal and restrained eating; appearance-esteem partially mediated effects in the emotional and external eating regressions. In females, both weight-esteem and appearance-esteem partially mediated the relationship between thin ideal and all three forms of disordered eating; weight-esteem was a stronger mediator for restrained eating, and appearance-esteem a stronger mediator for emotional and external eating. Body esteem is important to consider for prevention and treatment of disordered eating in both genders.  相似文献   

11.
We propose that spatial imagery is systematically linked to stereotypic beliefs, such that more agentic groups are envisaged to the left of less agentic groups. This spatial agency bias was tested in three studies. In Study 1, a content analysis of over 200 images of male-female pairs (including artwork, photographs, and cartoons) showed that males were over-proportionally presented to the left of females, but only for couples in which the male was perceived as more agentic. Study 2 (N = 40) showed that people tend to draw males to the left of females, but only if they hold stereotypic beliefs that associate males with greater agency. Study 3 (N = 61) investigated whether scanning habits due to writing direction are responsible for the spatial agency bias. We found a tendency for Italian-speakers to position agentic groups (men and young people) to the left of less agentic groups (females and old people), but a reversal in Arabic-speakers who tended to position the more agentic groups to the right. Together, our results suggest a subtle spatial bias in the representation of social groups that seems to be linked to culturally determined writing/reading habits.  相似文献   

12.
Age norms for impulsiveness,venturesomeness and empathy in adults   总被引:1,自引:0,他引:1  
A total of 1320 Ss (559 males and 761 females) completed the I6 Impulsiveness Questionnaire. Reliabilities, scale intercorrelations, means and standard deviations as well as age means are given after some item changes from the original I5 Questionnaire. The resulting I7 Impulsiveness Questionnaire is reproduced in the Appendix, together with the scoring key. A further 589 Ss (383 males and 206 females) completed the new I7, together with the EPQ and intercorrelations of the seven factors obtained are given (i.e. Psychoticism, Extraversion, Neuroticism, Lie score, impulsiveness Venturesomeness and Empathy). A table of means and standard deviations for this second sample of Ss is also given for the sake of completeness.  相似文献   

13.
We develop a simple model of switching between the initial links of a concurrent-chain procedure. Behavior is determined by four parameters μ1, μ2, q1, and q2. The first two are the basic rates of switching from Schedule 1 and Schedule 2, respectively. The second two are the probabilities of leaving Schedule 1 and Schedule 2 after the corresponding terminal link has been completed. We show that for fixed values of these four parameters, the relative allocation on the initial links may change as a result of changes in initial-link schedules. The effect can be quite large if the switching rates are low. An implication is that relative allocation is not necessarily a good measure of behavior.  相似文献   

14.
The general psychophysical differential equation, dy/dx = W2(y)/W1(x), with the solution y = f(x), where x and y are subjective variables and W1 and W2 their subjective Weber functions, is (a) compared with a corresponding functional equation, and (b) studied from a stochastic point of view by error calculus, Methods for evaluating and handling divergences are proposed and illustrated for a number of combinations of Weber functions. It is shown that either the differential: and the functional equations have the same solution or the difference between the solutions is negligible compared to empirical scatter. The error calculus gives the same result: either no error at all or a negligible one.  相似文献   

15.
The current study investigated relations between the perceived ability to deceive and the Dark Triad personality traits in two samples. In study 1, the sample consisted of 1074 participants (329 male, 745 female) aged 17–71 years (M = 22.96, SD = 6.92). Participants completed the perceived ability to deceive scale, in which they were asked to estimate the percentage of people who are worse at lying than they are in a number of situations. Participants also completed the Short-D3 – a measure of the Dark Triad personality traits. As expected, correlational analyses demonstrated that Machiavellianism was most highly correlated with the perceived ability to deceive (r = .41), followed by psychopathy (r = .35), and narcissism (r = .33). These findings were replicated in study 2, which consisted of 1448 undergraduate students (498 males, 947 females, 3 other), aged 18–43 (M = 18.35, SD = 1.77). Study 2 also investigated the association of the Dark Triad and perceived ability to deceive with dimensions of the Big Five model of personality. Implications are discussed.  相似文献   

16.
The importance of considering age and sex differences in the assessment of motor performance has been largely overlooked. This study examines the psychometric properties of the US developed McCarron Assessment of Neuromuscular Development (MAND) using data from a longitudinal sample of 986 Australian youth at 10, 14 and 17 years. A key finding was the sex and age interaction of the Neuromuscular Developmental Index (NDI) (F = 121.46, p < .001). Males had a significantly lower mean NDI score at 10 years and the females had a lower score at 17 years. The factor structure differed from the US samples ( McCarron, 1997) at each age and between males and females. The sex specific analyses showed that the underlying structure was more complex for younger females. Although the MAND remains a useful test of motor performance for Australian children, further consideration is warranted regarding sex differences, the relevance of the US based normative tables and factor structures.  相似文献   

17.
The current study tested the hypothesis that digit ratios would be associated with celebrity worship, especially among adolescents. Our sample consisted of 45 male and 61 female participants aged 12-14 years (M = 13.20, SD = 0.71). We measured the digit ratios on the participants’ right hands and used the 23 items of the revised Celebrity Attitude Scale (CAS) to explore the degree to which participants engaged in celebrity worship. The average digit ratio was 0.95 (SD = 0.04) among male participants and 0.97 (SD = 0.05) among female participants. The mean CAS scores were 50.06 (SD = 20.63) for male participants and 64.49 (SD = 18.04) for female participants. The digit ratios for the entire sample were positively correlated with CAS scores (r = 0.29, p < 0.005). However, the digit ratios were positively correlated with CAS scores among female (r = 0.51, p < 0.001) but not male (r = −0.13, p = .394) participants. Our research found evidence of a significant positive correlation between 2D:4D ratios and celebrity worship in females but not in males, which indicated that females with lower digit ratios were less likely to worship celebrities.  相似文献   

18.
The cerebral cortical correlates of the susceptibility to hypnosis in the ordinary states of consciousness have not been clarified. Aim of the study was to characterize the EEG dynamics of subjects with high (highs) and low hypnotisability (lows) through the non-linear method of Recurrence Quantification Analysis (RQA). The EEG of 16 males – 8 highs and 8 lows – was monitored for 1 min without instructions other than keeping the eyes closed, being silent and avoiding movements (short resting), and during 15 min of simple relaxation, that is with the instruction to relax at their best. Highs and lows were compared on the RQA measures of Determinism (DET) and Entropy (ENT), which are related to the signal determinism and complexity. In the short resting condition discriminant analysis could classify highs and lows on the basis of DET and ENT values at temporo-parietal sites. Many differences in DET and all differences in ENT disappeared during simple relaxation, although DET still separated the two groups in the earliest 6 min of relaxation at temporo-parietal sites. Our RQA based approach allows to develop computer-based methods of hypnotic assessment using short-lasting, single channel EEG recordings analyzed through standard mathematical methods.  相似文献   

19.
Two interpretations of the equations used by B. Inhelder and J. Piaget in The growth of logical thinking from childhood to adolescence (London: Routledge & Kegan Paul, 1958) are discussed, with implication as the central example. The expression (p ? q) (p implies q) is said to be equal to (p · q) V (p · q) V (p · q) (i.e.,p and q, or not p and q, or neither p nor q). According to one, (p ? q) asserts the existence of each case mentioned. According to the other, (p ? q) only asserts that current knowledge allows the possibility of each of the cases. Neither interpretation makes sense of all the relevant passages. Both can be combined in a consistent interpretation when attention is paid to the functional context of the subject's use of logical operations in this book: the “operations” describe the knowledge states which the subject can differentiate and relate, on his way to solving Inhelder's tasks. The logical notation used to represent these states is not a representational format attributed to the subject and manipulated by his cognitive processes, but part of a structuralist account of the subject's reasoning capacities.  相似文献   

20.
2D:4D, the length ratio of the second to the fourth digit, is a putative measure of prenatal testosterone, which may have effects on aggression and risk taking. Participants in a German online study (>1000 females, >1200 males) submitted their self-measured digit lengths and self-report measures on verbal and physical aggression and risk taking. For males, left-hand 2D:4D and verbal aggression correlated significantly (r = −.10, after correction for age and reduced reliability in self-measured 2D:4D), with other relationships being similar but non-significant. For females, no relationships between aggression and 2D:4D were found. Risk taking and right-hand 2D:4D correlated significantly in women (r = −.10, after correction for age and reduced reliability in self-measured 2D:4D); similar, but statistically non-significant, relationships were found in men. The result corroborates an emerging view that 2D:4D is negatively related to aggression in males and that 2D:4D is negatively related to risk taking. This tentatively points to effects of prenatal testosterone on these characteristics.  相似文献   

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