The roles of location specificity and masking mechanisms in the attentional blink.

In a series of four experiments using rapid serial visual presentations of two target letters embedded in numeral distractors, with different numbers of display positions and with or without masking, we show that (1) the nonmonotonic, U-shaped attentional blink (AB) function, which occurs when all items are presented at the same display location, is eliminated in favor of a monotonic function when targets and distractors are presented randomly dispersed over four or nine adjacent positions; (2) the AB monotonicity is maintained with the spatially distributed presentation even when backward masks are used in all possible stimulus positions and when the location of the next item in sequence is predictable; and (3) the U-shaped AB is not due to position-specific forward or backward masking effects occurring at early levels of visual processing. We tentatively conclude that the U-shaped AB is primarily a function of the interruption of late visual processing produced when the item following the first target occurs at the same location. In order for the AB to severely disrupt performance, the item following the first target must be presented at the same location as the target so that it can serve both as a distractor and as a mask interrupting of interfering with subsequent visual processing.     

A longitudinal study of bilingual and cognitive development(1)

This paper presents the findings of a longitudinal study of IQ data collected over a 5-year period (Grades K-4) on pupils enrolled in a French immersion program (anglophone pupils receiving all instruction in French except English language arts) and pupils in the regular English program. Although year-by-year results may fail to show IQ differences between the two groups, repeated measures analysis indicates that the immersion group has a higher IQ measure over the 5-year period. However, considering Grades 1–3 only, which involved the administration of the same test, the two groups do not score differentially with respect to either overall IQ measure or specific subtest scores (classification/categorization, analogies, following of verbal directions) when scores are adjusted for initial IQ (and age) differences, thus failing initially to support studies which show positive relationships between bilingualism and cognitive functioning. However, supportive of those studies is a further analysis on the data of immersion pupils classified as “high” French achievers vs. “low” French achievers. The high French achievers obtain significantly higher IQ measures and subtest scores (analogies and following of verbal directions) than the low French achievers, even when scores are adjusted for initial IQ and age differences. These findings are interpreted in the context of Cummins' (1976) “threshold” hypothesis relating to level of competence in the second language.     

Food and intracranial stimulation responding suppressed with regular-interval shock.

Attenuation of conditioned suppression during intracranial stimulation was compared with that during food reinforcement. Response rates controlled by food and by brain stimulation were equalized on a multiple schedule by adjusting the stimulating current. When foot shock was delivered during timeout periods separating response components, responding for food was significantly more suppressed than responding for brain stimulation. When components were shortened from 10 to 2 minutes, responding maintained by either food or brain stimulation showed a similar temporal pattern of suppression preceding each shock, but responding in the component involving food remained significantly more suppressed. Explanations for the attenuated suppression during brain stimulation based on neural disruption, stimulus blocking, and analgesic properties were questioned. The increased responding during brain stimulation seemed to reflect greater response strength relative to food reinforced responding.     

Cognitive and Personality Characteristics of Masculinity and Femininity Predict Wayfinding Competence and Strategies of Men and Women

Bem (1974) reconceptualized masculinity and femininity as independent and orthogonal constructs that both men and women possess to varying degrees. This perspective was used as a starting point to investigate whether the contributions of gender-typed characteristics can help to account for commonly observed gender differences in wayfinding (the ability to identify one’s current location and successfully navigate to an unseen location in the environment) favoring men. We further divided gender-typed characteristics into cognitive and personality characteristics to assess their separate influence on wayfinding and explored whether gender-typed characteristics predicted self-reported use of masculine wayfinding strategies (i.e., orientation strategies) and self-reported wayfinding competence. Participants were 452 college women and men in a southern U.S. public university. They completed the Gender-Stereotypic Characteristics questionnaire (Diekman and Eagly 2000), a social comparison questionnaire (created by the authors), a wayfinding strategy questionnaire (Lawton 1994), and a wayfinding competence questionnaire (Hegarty et al. 2002). For both men and women, higher masculine cognitive characteristics significantly correlated with greater use of orientation wayfinding strategies typical of men. For men, both higher masculine and feminine cognitive characteristics predicted better overall wayfinding competence whereas for women, only higher masculine cognitive characteristics predicted better overall wayfinding competence. For both men and women, higher feminine personality characteristics predicted poorer wayfinding competence. These results demonstrated the importance of considering cognitive and personality characteristics of masculinity and femininity in explaining individual differences in wayfinding.