Salience from multiple feature contrast: Evidence from saccade trajectories

We used eye tracking to quantify the extent to which combinations of salient contrasts (orientation, luminance, and movement) influence a central salience map that guides eye movements. We found that luminance combined additively with orientation and movement, suggesting that the salience system processes luminance somewhat independently of the two other features. On the other hand, orientation and movement together influenced salience underadditively, suggesting that these two features are processed nonindependently. This pattern of results suggests that the visual system does not sum sources of salience linearly, but treats some sources of salience as redundant.

     

INTRA-PAIR SIMILARITIES IN THE SCHOOL ACHIEVEMENTS OF TWINS

The present investigation is part of a follow-up study of twins from grade 4 through 8 (age 11 through 15). Intra-pair similarities are studied, intra-class correlations being used as a criterion of similarity. Scores on achievement tests administered to practically all the twins in grade 4 in Sweden were collected and analyzed. The intra-class correlations obtained for an age group of twins in grade 6 are throughout higher than those obtained in grade 4. The findings refute the additive model of hereditary and environmental influences. Two alternative hypotheses are advanced to explain the results. Previous findings indicating an average superiority of single-borns over twins in cognitive tests are confirmed.     

DNA Testing for Family Reunification in Canada: Points to Consider

Countries have adopted different laws, policies, and practices that allow immigration officers to request in certain cases DNA tests to confirm biological relationships in the context of family reunification. In Canada, Citizenship and Immigration Canada has adopted a policy of suggesting DNA testing only as a last resort in cases where no documentary evidence has been submitted or where the evidence provided is deemed unsatisfactory. However, in practice, there have been concerns on the increasing use of DNA tests in family reunification processes of nationals from certain regions including Africa, Asia, and Latin America. Moreover, the Immigration and Refugee Protection Regulations (IRPR) presents a biological definition of family as a determinant of parenthood in the context of family reunification that is inconsistent with the psychosocial definition used in provincial family laws. Although there are cases that can justify the request for DNA tests, there are also significant social, legal, and ethical issues, including discrimination and unfair practices, raised by this increasing use of genetic information in immigration. This policy brief identifies points to consider for policymakers regarding the use of DNA testing in Canadian family reunification procedures. These include (1) the need to refine the policy of “using DNA testing as a last resort” and its implementation, (2) the need to modify the definition of “dependent child” under the IRPR to reflect the intrinsic reality of psychosocial family ties, and (3) the importance of conducting more research on the use of DNA testing in other immigration contexts.     

Soccer referees’ experience of threat and aggression: Effects of age,experience, and life orientation on outcome of coping strategy

The present study examined the circumstances pertaining to threat and aggression during soccer matches as experienced by 107 provincial Soccer Association referees. Three sources of aggression were identified—soccer players, coaches/trainers, and spectators—and the main measures included threat and physical and verbal aggression. Several outcomes, including prematch worry and effects on concentration, performance, and motivation, were affected by the incidence of threat and aggression, and these outcomes were found to be affected by the age, degree of experience, and life orientation of the referees. Younger referees were shown to be the most prone to threat and aggression. Referees with a generally pessimistic orientation experienced less motivation, worse performance, and greater problems coping with aggressive behavior from the spectators compared with referees with a generally optimistic orientation. Aggr. Behav. 28:317–327, 2002. © 2002 Wiley‐Liss, Inc.     

Speaking with a single cerebral hemisphere: fMRI language organization after hemispherectomy in childhood

Speech-related fMRI activation was examined in six hemispherectomy patients (three left LX, three right RX, four with congenital and two with late-acquired hemiplegia) operated in childhood for the relief of drug-resistant epilepsy. Although the temporal and sensorimotor pattern of activation was similar to that found in neurologically intact control participants, activation in Broca's area and its right homolog varied greatly. Involvement of pars triangularis and orbitalis was found in the three cases with best outcome (two RX, one LX), whereas pars opercularis alone was activated in the two remaining LX patients. The results suggest that distinct subregions of Broca's area and their right homologs can subserve speech and language, and that this variability may determine functional outcome.     

A validation and short form of the Basic Character Inventory

The Basic Character Inventory (BCI) contains 136 items, 17 lower-order personality factors and three higher-order personality factors derived from psychoanalytic theory: Oral, Obsessive Compulsion, and Hysteria. Previous research that investigated the BCI's psychometric properties examined small, special populations and did not use modern statistical methods to validate the BCI. The present study validates the BCI via confirmatory factor analyses using a large sample of 6,285 Norwegian nursing and teaching students. Reliability, convergent validity, and divergent validity of the BCI were also assessed. Results indicated general support for the original BCI factor structure in a reduced form of the BCI that possesses strong reliability and validity, and is suitable for use in time-limited measurement settings.     

The neural effect of stimulus-response modality compatibility on dual-task performance: an fMRI study

Recent fMRI studies suggest that the inferior frontal sulcus (IFS) is involved in the coordination of interfering processes in dual-task situations. The present study aims to further specify this assumption by investigating whether the compatibility between stimulus and response modalities modulates dual-task-related activity along the IFS. It has been shown behaviorally that the degree of interference, as measured by dual-task costs, increases in modality-incompatible conditions (e.g. visual–vocal tasks combined with auditory–manual tasks) as compared to modality-compatible conditions (e.g. visual–manual tasks combined with auditory–vocal tasks). Using fMRI, we measured IFS activity when participants performed modality-compatible and modality-incompatible single and dual tasks. Behaviorally, we replicated the finding of higher dual-task costs for modality-incompatible tasks compared to modality-compatible tasks. The fMRI data revealed higher activity along the IFS in modality-incompatible dual tasks compared with modality-compatible dual tasks when inter-individual variability in functional brain organization is taken into account. We argue that in addition to temporal order coordination (Szameitat et al., 2002), the IFS is involved in the coordination of cognitive processes associated with the concurrent mapping of sensory information onto corresponding motor responses in dual-task situations.     

Predicting performance in ski and swim championships: effectiveness of mood, perceived exertion, and dispositional optimism

Two studies were performed with young athletes to investigate the utility of three psychological tests regarding the prediction of sport performance: the Profile of Mood States. Ratings of Perceived Exertion, and Dispositional Optimism. In Study 1, young male and female cross-country skiers and ski-marksmen in final preparation for the Junior National Swedish Championships were tested. Measured 5 wk. before both competitions, the higher the optimism (LOT), the better performance. In Study 2, which tested young swimmers in preparation for the Senior National Swedish Championships, competitors who had the highest scores on optimism performed less well during the competitions. The results are interpreted to indicate that optimism presents an important factor for predicting achievement in sports.     

Femininity and fertility in sisters with twin brothers: prenatal androgenization? Cross-sex socialization?

Are sisters of twin brothers behaviorally or physiologically masculinized? Prenatal exposure to their brothers' androgens and postnatal socialization experiences unique to girls growing up with twin brothers might influence their attitudes, pubertal development, and reproductive histories. To investigate, we studied age- and cohort-matched samples of Finnish sisters from same-sex and opposite-sex twin pairs. Using data from two ongoing longitudinal studies of consecutive birth cohorts of Finnish twins, we assessed pubertal development at ages 11 and 14 and endorsement of attitudes associated with femininity at age 16. We also studied fertility in Finnish women from same- and opposite-sex twin pairs born from 1958 through 1971, obtaining information on their child-bearing histories when they were ages 15 to 28. Results of each comparison were unambiguously negative: There was no evidence of differences between sisters from same- and opposite-sex twin pairs, and thus, no evidence of either androgenization or cross-sex socialization.