Sorting and convergence of primary olfactory axons are independent of the olfactory bulb

Primary olfactory axons expressing the same odorant receptor gene sort out and converge to fixed sites in the olfactory bulb. We examined the guidance of axons expressing the P2 odorant receptor when they were challenged with different cellular environments in vivo. In the mutant extratoes mouse, the olfactory bulb is lacking and is replaced by a fibrocellular mass. In these animals, primary olfactory axons form glomerular-like loci despite the absence of normal postsynaptic targets. P2 axons are able to sort out from other axons in this fibrocellular mass and converge to form loci of like axons. The sites of these loci along mediolateral and ventrodorsal axes were highly variable. Similar convergence was observed for larger subpopulations of axons expressing the same cell surface carbohydrates. The sorting out and convergence of like axons also occurred during regeneration following bulbectomy. Olfactory axon behaviour in these models demonstrates that sorting and convergence of axons are independent of the target, which instead provides distinct topographic cues for guidance. (C) 2003 Wiley-Liss, Inc.

Sport-specific practice and the development of expert decision-making in team ball sports

The role of sport-specific practice in the development of decision-making expertise in the sports of field hockey, netball, and basketball was examined. Fifteen expert decision-makers and 13 experienced non-expert athletes provided detailed information about the quantity and type of sport-specific and other related practice activities they had undertaken throughout their careers. Experts accumulated more hours of sport-specific practice from age 12 years onwards than did non-experts, spending on average some 13 years and 4,000 hours on concentrated sport-specific practice before reaching international standard. A significant negative correlation existed between the number of additional activities undertaken and the hours of sportspecific training required before attaining expertise, suggesting a functional role for activities other than sport-specific training in the development of expert decision-making.

Emergence of joint attention: Relationships between gaze following, social referencing, imitation, and naming in infancy

The authors investigated the extent to which the joint-attention behaviors of gaze following, social referencing, and object-directed imitation were related to each other and to infants vocabulary development in a sample of 60 infants between the ages of 8 and 14 months. Joint-attention skills and vocabulary development were assessed in a laboratory setting. Split-half reliability analyses on the joint-attention measures indicated that the tasks reliably assessed infants' capabilities. In the main analysis, no significant correlations were found among the joint-attention behaviors except for a significant relationship between gaze following and the number of names in infants' productive vocabularies. The overall pattern of results did not replicate results of previous studies (e.g., M. Carpenter, K. Nagell, & M. Tomasello, 1998) that found relationships between various emerging joint-attention behaviors.

Attitude-behaviour consistency: the role of group norms, attitude accessibility, and mode of behavioural decision-making

The interplay between two perspectives that have recently been applied in the attitude area-the social identity approach to attitude-behaviour relations (Terry & Hogg, 1996) and the MODE model (Fazio, 1990a)-was examined in the present research. Two experimental studies were conducted to examine the role of group norms, group identification, attitude accessibility, and mode of behavioural decision-making in the attitude-behaviour relationship. In Study I (N = 211), the effects of norms and identification on attitude-behaviour consistency as a function of attitude accessibility and mood were investigated. Study 2 (N = 354) replicated and extended the first experiment by using time pressure to manipulate mode of behavioural decision-making. As expected, the effects of norm congruency varied as a function of identification and mode of behavioural decision-making. Under conditions assumed to promote deliberative processing (neutral mood/low time pressure), high identifiers behaved in a manner consistent with the norm. No effects emerged under positive mood and high time pressure conditions. In Study 2, there was evidence that exposure to an attitude-incongruent norm resulted in attitude change only under low accessibility conditions. The results of these studies highlight the powerful role of group norms in directing individual behaviour and suggest limited support for the MODE model in this context. Copyright (C) 2003 John Wiley Sons, Ltd.

Linking superiority bias in the interpersonal and intergroup domains

The author conducted 2 studies to explore the link between superiority bias in the interpersonal and intergroup domains. Australian university students evaluated the extent to which various personality traits were more or less applicable to themselves than to other Australian university students in general. They then evaluated the extent to which the same traits were more or less applicable to Australians than to people from other countries in general. As expected, the more participants evaluated themselves as superior to other university students, the more they evaluated Australians as a whole as superior to people from other countries. This link between interpersonal and intergroup superiority biases explained 22.1% of variance in Study 1 and 33.6% of variance in Study 2. The author interprets the results of the 2 studies as support for fundamental principles of social identity theory: (a) that self-concept consists of not only one's personal self but also the social groups to which one belongs and (b) that people are motivated to view both levels of self in a relatively positive fashion.

Stem-completion priming for words studied in sentences: The context deletion effect under direct and indirect memory instructions

Two studies investigated the context deletion effect, the attenuation of priming in implicit memory tests of words when words have been studied in text rather than in isolation. In Experiment 1, stem completion for single words was primed to a greater extent by words studied alone than in sentence contexts, and a higher proportion of completions from studied words was produced under direct instructions (cued recall) than under indirect instructions (produce the first completion that comes to mind). The effect of a sentence context was eliminated when participants were instructed to attend to the target word during the imagery generation task used in the study phase. In Experiment 2, the effect of a sentence context at study was reduced when the target word was presented in distinctive format within the sentence, and the study task (grammatical judgment) was directed at a word other than the target. The results implicate conceptual and perceptual processes that distinguish a word from its context in priming in word stem completion.

Social approval and trait self-esteem

Interpersonal theories of self-esteem that tie self-esteem to perceptions of ones acceptability to other people suggest that self-evaluations should predict global self-esteem to the degree to which an individual believes that a particular attribute is important for social approval. In the present study, participants completed a measure of global self-esteem, rated themselves in five domains, and indicated how important those domains were for approval or disapproval. The results showed that, in four of five domains, the interaction between self-evaluations and the perceived approval-value of that domain aided in the prediction of global self-esteem. Generally, for participants who rated themselves positively in a domain, those who believed that the domain was important in affecting social approval or disapproval had higher self-esteem than those who did not believe it would influence acceptability.

Attachment insecurity, depression, and the transition to parenthood

In a longitudinal study of adult attachment and depression during the transition to parenthood, 76 couples completed questionnaires on three occasions: during the second trimester of pregnancy, and six weeks and six months postbirth. On the first and second occasions, the couples were also interviewed about their experiences of pregnancy and parenthood, respectively. Measures were also completed at similar time intervals by a comparison group of 74 childless couples. Attachment security was assessed in terms of the dimensions of discomfort with closeness and relationship anxiety. Relationship anxiety was less stable for transition wives than for other participants. Relationship anxiety also predicted increases in new mothers' depressive symptoms, after controlling for a broad range of other risk factors. However, the association between relationship anxiety and maternal depression was moderated by husbands' caregiving style. Maternal depression was linked to increases in husbands' and wives' attachment insecurity and marital dissatisfaction. Results are discussed in terms of the impact of depression and negative working models of attachment on couple interaction.

The role of gender in the construction and evaluation of feedback effectiveness

This study investigated factors that influence managers’ conceptions and subordinates’ perceptions of effective feedback. A social rules perspective was used to operationalize male and female managers’ conceptions of effective negative feedback. In the first study, 68 male and female managers identified their optimal strategies for providing feedback to subordinates. Male and female managers endorsed different goals and tactics for giving negative feedback, particularly in terms of levels of participation and directness. In the second study, 116 male and female subordinates evaluated the comparative effectiveness and difficulty of these and other standard approaches to feedback. The female manager strategy was evaluated by both men and women as generally more task and relationship effective but not more difficult to enact.

Early alterations in serum creatine kinase and total cholesterol following high intensity eccentric muscle actions

Aim. The purpose of this experiment was to assess the levels of muscle soreness, serum total cholesterol (TC) and creatine kinase (CK) in the first 48 hours following fatiguing eccentric exercise performed with the triceps brachii. Methods. Eleven untrained male college students performed a total of 50 eccentric elbow extensions in 8 sets (6x7 and 2x4) with a load equal to 85% of their maximal concentric elbow extension strength. Isometric elbow extension strength, muscle soreness and circumference, and serum CK and TC concentrations were measured before, immediately after, and 2, 24 and 48 hours after the exercise. Results. Statistically reliable changes in isometric strength, serum CK and TC, muscle soreness and upper arm circumference occurred within the first 48 hours following eccentric exercise. Serum TC concentrations exhibited a very rapid (within 2 hours) reduction from pre-exercise values after eccentric exercise to a relatively stable concentration of approximately 85% of baseline. Conclusion. These results suggest that serum TC concentration may follow the time-course of reductions in force generating capacity more closely than other biochemical markers of muscle damage.

Pretend play, mirror self-recognition and imitation: A longitudinal investigation through the second year

The aim in the current study was to investigate the emergence of pretend play, mirror self-recognition, synchronic imitation and deferred imitation in normally developing human infants. A longitudinal study was conducted with 98 infants seen at three-monthly intervals from 12 through to 24 months of age. At each session the infants were tested on a range of tasks assessing the four target skills. Deferred imitation was found to emerge prior to synchronic imitation, pretend play and mirror self-recognition. In contrast, the latter three skills emerged between 18 and 21 months and followed similar developmental trajectories. Deferred imitation was found to hold a prerequisite relation with these three skills. Synchronic imitation, pretend play and mirror self-recognition were not closely associated and no prerequisite relations were found between these skills. These findings are discussed in the context of current theories regarding the development of pretend play, mirror self-recognition, synchronic imitation and deferred imitation in the second year. (C) 2004 Elsevier Inc. All rights reserved.

Country of birth, country of residence, and menopausal transitions and symptoms: British birth cohort and Australian Longitudinal Study on Women's Health

Objective: To explore endocrine-related and general symptoms among three groups of middle-aged women defined by country of birth and country of residence, in the context of debates about biological, cultural and other factors in menopause. Methods: British-born women participating in a British birth cohort study (n=1,362) and age-matched Australian-born (n=1,724) and British-born (n=233) Australian women selected from the Australian Longitudinal Study on Women's Health (ALSWH) responded to two waves of surveys at ages 48 and 50. Results: Australian-Australian and British-Australian women report reaching menopause later than British-British women, even after accounting for smoking status and parity. Hormone replacement therapy (HRT) use was lower and hysterectomy was more common among both Australian groups, probably reflecting differences in health services between Britain and Australia. The Australian-Australian and British-Australian groups were more likely to report endocrine-related symptoms than the British-British group, even after adjusting for menopausal status. British-British women were more likely to report some general symptoms. Conclusions: Symptom reporting is high among Australian and British midlife women and varies by country of residence, country of birth and menopausal status. Implications: The data do not support either a simple cultural or a simple biological explanation for differences in menopause experience.

Appetitive motivation predicts the majority of personality and an ability measure: a comparison of BAS measures and a re-evaluation of the importance of RST

Our first study develops a measure of appetitive motivation and our second study compares several measures of Gray's (1987) behaviour activation system (BAS) in the prediction of the surface scales of personality. In particular, we were interested in determining the utility of the new appetitive motivation scale and Dickman's functional impulsivity scale. In comparison to other well-known measures, both scales were generally good predictors. We conclude that the appetitive motivation scale is a promising measure of BAS based upon construct validation. Contrary to previous studies which have suggested that BAS is a generally poor predictor of the surface scales of personality, we discovered appetitive motivation to be an important predictor of personality in general. Interestingly, the scale was also predictive of scores on the Baddeley reasoning test. (C) 2003 Elsevier Ltd. All rights reserved.

Cultural and gender influences on age identification

Age identification plays a significant role in young adults" mass, interpersonal, intergenerational, and intercultural communication. This research examines cultural and gender influences on young people's age identity by measuring the social age identity of male and female young adult members of five cultures varying in individualism/collectivism (Laos, Thailand, Spain, Australia, and the U.S.A.). We found cultural influences on age identity to be both unexpected in nature and modest in effect. American and Laotian respondents had similar and nominally higher levels of age identity than Australian, Thai, and Spanish respondents, with all having a markedly different age identities than those of Japanese respondents as reported by other researchers. No direct effect for gender on age identity emerged, though American females were more age identified than all other respondents. Across cultures, the social identity scale was found to be a reasonably adequate measure of age identity.

A parent-report measure of children's anxiety: psychometric properties and comparison with child-report in a clinic and normal sample

This study examined the psychometric properties of the parent version of the Spence Children's Anxiety Scale (SCAS-P); 484 parents of anxiety disordered children and 261 parents in a normal control group participated in the study. Results of confirmatory factor analysis provided support for six intercorrelated factors, that corresponded with the child self-report as well as with the classification of anxiety disorders by DSM-IV (namely separation anxiety, generalized anxiety, social phobia, panic/agoraphobia, obsessive-compulsive disorder, and fear of physical injuries). A post-hoc model in which generalized anxiety functioned as the higher order factor for the other five factors described the data equally well. The reliability of the subscales was satisfactory to excellent. Evidence was found for both convergent and divergent validity: the measure correlated well with the parent report for internalizing symptoms, and lower with externalizing symptoms. Parent-child agreement ranged from 0.41 to 0.66 in the anxiety-disordered group, and from 0.23 to 0.60 in the control group. The measure differentiated significantly between anxiety-disordered children versus controls, and also between the different anxiety disorders except GAD. The SCAS-P is recommended as a screening instrument for normal children and as a diagnostic instrument in clinical settings. (C) 2003 Elsevier Ltd. All rights reserved.