How is the serial order of a verbal sequence coded? Some comparisons between models

Current models of verbal short-term memory (STM) propose various mechanisms for serial order. These include a gradient of activation over items, associations between items, and associations between items and their positions relative to the start or end of a sequence. We compared models using a variant of Hebb's procedure in which immediate serial recall of a sequence improves if the sequence is presented more than once. However, instead of repeating a complete sequence, we repeated different aspects of serial order information common to training lists and a subsequent test list. In Experiment 1, training lists repeated all the item-item pairings in the test list, with or without the position-item pairings in the test list. Substantial learning relative to a control condition was observed only when training lists repeated item-item pairs with position-item pairs, and position was defined relative to the start rather than end of a sequence. Experiment 2 attempted to analyse the basis of this learning effect further by repeating fragments of the test list during training, where fragments consisted of either isolated position-item pairings or clusters of both position-item and item-item pairings. Repetition of sequence fragments led to only weak learning effects. However, where learning was observed it was for specific position-item pairings. We conclude that positional cues play an important role in the coding of serial order in memory but that the information required to learn a sequence goes beyond position-item associations. We suggest that whereas STM for a novel sequence is based on positional cues, learning a sequence involves the development of some additional representation of the sequence as a whole.     

Communal versus individual learning of a math-estimation task: African American children and the culture of learning contexts

The authors compared the performance of 78 African American 5th-grade students who studied a math-estimation task in one of two learning contexts. Learning contexts differed in the degree to which they afforded the expression of communalism. ANCOVA confirmed that posttest performance was best for students who studied in the high communal-learning context. The findings support A. W. Boykin's (1994) contention that the cultural context of learning can be a critical mediator of children's performance.     

Pain modulation during drives through cold and hot virtual environments.

Evidence exists that virtual worlds reduce pain perception by providing distraction. However, there is no experimental study to show that the type of world used in virtual reality (VR) distraction influences pain perception. Therefore, we investigated whether pain triggered by heat or cold stimuli is modulated by "warm "or "cold " virtual environments and whether virtual worlds reduce pain perception more than does static picture presentation. We expected that cold worlds would reduce pain perception from heat stimuli, while warm environments would reduce pain perception from cold stimuli. Additionally, both virtual worlds should reduce pain perception in general. Heat and cold pain stimuli thresholds were assessed outside VR in 48 volunteers in a balanced crossover design. Participants completed three 4-minute assessment periods: virtual "walks " through (1) a winter and (2) an autumn landscape and static exposure to (3) a neutral landscape. During each period, five heat stimuli or three cold stimuli were delivered via a thermode on the participant's arm, and affective and sensory pain perceptions were rated. Then the thermode was changed to the other arm, and the procedure was repeated with the opposite pain stimuli (heat or cold). We found that both warm and cold virtual environments reduced pain intensity and unpleasantness for heat and cold pain stimuli when compared to the control condition. Since participants wore a head-mounted display (HMD) in both the control condition and VR, we concluded that the distracting value of virtual environments is not explained solely by excluding perception of the real world. Although VR reduced pain unpleasantness, we found no difference in efficacy between the types of virtual world used for each pain stimulus.     

Predicting Early Sexual Activity with Behavior Problems Exhibited at School Entry and in Early Adolescence

Youth who initiate sexual intercourse in early adolescence (age 11–14) experience multiple risks, including concurrent adjustment problems and unsafe sexual practices. The current study tested two models describing the links between childhood precursors, early adolescent risk factors, and adolescent sexual activity: a cumulative model and a meditational model. A longitudinal sample of 694 boys and girls from four geographical locations was utilized, with data collected from kindergarten through high school. Structural equation models revealed that, irrespective of gender or race, high rates of aggressive disruptive behaviors and attention problems at school entry increased risk for a constellation of problem behaviors in middle school (school maladjustment, antisocial activity, and substance use) which, in turn, promoted the early initiation of sexual activity. Implications are discussed for developmental models of early sexual activity and for prevention programming.

Perceived discrimination as worldview threat or worldview confirmation: implications for self-esteem

In 3 studies, the authors tested the hypothesis that discrimination targets' worldview moderates the impact of perceived discrimination on self-esteem among devalued groups. In Study 1, perceiving discrimination against the ingroup was negatively associated with self-esteem among Latino Americans who endorsed a meritocracy worldview (e.g., believed that individuals of any group can get ahead in America and that success stems from hard work) but was positively associated with self-esteem among those who rejected this worldview. Study 2 showed that exposure to discrimination against their ingroup (vs. a non-self-relevant group) led to lower self-esteem, greater feelings of personal vulnerability, and ingroup blame among Latino Americans who endorsed a meritocracy worldview but to higher self-esteem and decreased ingroup blame among Latino Americans who rejected it. Study 3 showed that compared with women informed that prejudice against their ingroup is pervasive, women informed that prejudice against their ingroup is rare had higher self-esteem if they endorsed a meritocracy worldview but lower self-esteem if they rejected this worldview. Findings support the idea that perceiving discrimination against one's ingroup threatens the worldview of individuals who believe that status in society is earned but confirms the worldview of individuals who do not.     

From "in the air" to "under the skin": cortisol responses to social identity threat

The authors examined women's neuroendocrine stress responses associated with sexism. They predicted that, when being evaluated by a man, women who chronically perceive more sexism would experience more stress unless the situation contained overt cues that sexism would not occur. The authors measured stress as the end product of the primary stress system linked to social evaluative threat-the hypothalamic-pituitary-adrenal cortical axis. In Study 1, female participants were rejected by a male confederate in favor of another male for sexist reasons or in favor of another female for merit-based reasons. In Study 2, female participants interacted with a male confederate who they learned held sexist attitudes or whose attitudes were unknown. Participants with higher chronic perceptions of sexism had higher cortisol, unless the situation contained cues that sexism was not possible. These results illustrate the powerful interactive effects of chronic perceptions of sexism and situational cues on women's stress reactivity.     

Early maturation of frequency-following responses to voice pitch in infants with normal hearing

Neural plasticity of pitch processing mechanisms at the human brainstem, as reflected by the scalp-recorded frequency-following response (FFR) to voice pitch, has been reported for normal-hearing adults. Characteristics and maturation of such a response during the first year of life have remained unclear. The purpose of this study was to examine the characteristics of FFR to voice pitch in normal-hearing infants and to make a direct comparison with adults using the same stimulus and recording parameters. 9 infants and 9 adults were recruited. A Chinese monosyllable that mimics the English vowel /i/ with a rising pitch was used to elicit the FFR to voice pitch. The results demonstrated that infant FFRs showed slightly larger Pitch Strength but comparable Frequency Error, Slope Error, and Tracking Accuracy to those obtained from adults. Early maturation of FFRs was also observed in the infants starting from 1 to 3 mo. of age.     

Physiological markers of challenge and threat mediate the effects of performance-based goals on performance

We predicted that adopting a performance-approach vs. performance-avoidance goal would lead to physiological responses characteristic of psychological states of challenge vs. threat appraisals, respectively. Furthermore, we predicted that these states would mediate the effects of goals on performance. Twenty-seven undergraduate females performed a task described as identifying either exceptionally strong performers (performance-approach goal) or exceptionally weak performers (performance-avoidance goal). Participants’ cardiovascular reactivity (CVR) was recorded while they performed the task. As predicted, participants in the performance-approach goal condition performed better on the task than did those in the performance-avoidance goal condition. Also as predicted, those in the former condition exhibited a challenge pattern of CVR whereas those in the latter condition exhibited a threat pattern of CVR. Furthermore, physiological responses mediated the effects of performance-based goals on performance.     

An Assessment of the Psychometric Properties of the Brief Sensation Seeking Scale for Children

Sensation seeking is a trait that predicts a wide range of real-life risk behavior, such as substance abuse and gambling problems. Sensation seeking is often assessed with the Sensation Seeking Scale. Several adaptations of this questionnaire have been made, for example, to abbreviate it and to make it suitable for children. However, studies on sensation seeking in children are scarce. The aim of this study was to investigate sensation seeking in children (N = 158, M age = 11.4 years). The Brief Sensation Seeking Scale for Children (BSSS–C) was translated into Dutch and psychometric properties were examined. Internal consistency was high, and the factor structure showed close resemblance with previous research. Test–retest and split-half reliabilities were acceptable, as was convergent validity with self-reported symptoms of psychopathology (attention problems and aggressive behavior). Construct validity was adequate, with more sensation seeking in boys than in girls. No effects of age were found. To sum up, sensation seeking can be measured in children in a valid and reliable way. The correlation of sensation seeking with high-risk behaviors emphasizes the importance of assessment early in development.     

When left means right: an explanation of the left cradling bias in terms of right hemisphere specializations

Previous research has indicated that 70-85% of women and girls show a bias to hold infants, or dolls, to the left side of their body. This bias is not matched in males (e.g. deChateau, Holmberg & Winberg, 1978; Todd, 1995). This study tests an explanation of cradling preferences in terms of hemispheric specialization for the perception of facial emotional expression. Thirty-two right-handed participants were given a behavioural test of lateralization and a cradling task. Females, but not males, who cradled a doll on the left side were found to have significantly higher laterality quotients than right cradlers. Results indicate that women cradle on the side of the body that is contralateral to the hemisphere dominant for face and emotion processing and suggest a possible explanation of gender differences in the incidence of cradling.