Stimulus repetition effects and the dimension-feature distinction in alternative targets

The negative repetition effect (NRE) refers to a poorer perception of the target in noise-same-as-target than in noise-alternative-target displays. Using the parenthesis as target and noise that are either identical or different in orientation, we tested predictions derived from a feature-specific inhibition model (Bjork & Murray, 1977) that explains the NRE as arising from inhibitory interactions among channels handling identical inputs. Contrary to our expectation of evidence for orientation-specific inhibition, a positive repetition effect (PRE) was observed. We also found a PRE for the dimension target sets whose stimuli differ only in orientation and an NRE for the feature target sets whose stimuli differ in the number of elements. Further experiments that systematically varied relationships between alternative targets indicate that these basic findings, termed the stimulus attributes effects, do not arise from pattern masking, perceptual strategies, or response bias.     

Cognition and metacognition at extreme altitudes on Mount Everest

The FACTRETRIEVAL2 test battery, which assesses both retrieval of general information from memory and metacognition about that retrieval, was administered to people before and after a recent expedition to Mount Everest and at extreme altitudes above 6,400 m (higher than any mountain in North America or Europe). The major findings were as follows: First, the same extreme altitudes already known to impair learning did not affect either accuracy or latency of retrieval, and this robustness of retrieval occurred for both recall and forced-choice recognition. Second, extreme altitude did affect metacognition: The climbers showed a decline in their feeling of knowing both while at extreme altitude and after returning to Kathmandu (i.e., both an effect and an aftereffect of extreme altitude). Third, extreme altitude had different effects than alcohol intoxication (previously assessed by Nelson. McSpadden, Fromme, & Marlatt, 1986). Alcohol intoxication affected retrieval without affecting metacognition, whereas extreme altitude affected metacognition without affecting retrieval; this different pattern for extreme altitude versus alcohol intoxication implies that (a) hypoxia does not always yield the same outcome as alcohol intoxication and (b) neither retrieval nor metacognition is strictly more sensitive than the other for detecting changes in independent variables.     

Do different metamemory judgments tap the same underlying aspects of memory?

We compared the predictions from several kinds of metamemory judgments (on the same set of items), both in terms of their predictive accuracy and in terms of the commonality of predictions. Undergraduates made judgments about the ease with which they could learn each item in a list (ease-of-learning judgments); then they learned every item, either to a minimal criterion of learning or with overlearning, and made judgments about how well they knew each item (judgments of knowing); finally, they returned 4 weeks later for a retention session and made feeling-of-knowing judgments on every time they could not recall, after which a recognition test assessed predictive accuracy. Ease-of-learning judgments had the least predictive accuracy. Surprisingly, however, the recognition of nonrecalled items was predicted equally well by judgments of knowing (made 4 weeks earlier) as by feeling-of-knowing judgments (made immediately prior to recognition). Moreover, those two kinds of judgments were only weakly correlated with each other, which implies that they do not tap memory in the same way.     

Adult sex typing of children's toys

A primary focus of this study was to determine whether adults use traditional sex-type standards when choosing toys for boys or girls. I also investigated whether an adult's sex or gender role influences this decision. College students were shown pictures of 74 toys, and were asked to indicate whether they would buy each toy for a boy or girl. Traditional sex-type ratings were found. In addition, male subjects sex-typed toys to a greater extent than female subjects. Subjects' gender role was unrelated to sex-type ratings. Subjects also judged whether each toy provided educational value, required activity, and encouraged cooperation. Toys rated as requiring activity were not considered educational, but many toys considered educational were also rated as encouraging cooperation. In addition, toys considered masculine were rated as requiring more activity than feminine toys.The author thanks Fran Rosati, Dawn Pillitteri, and Karen Molison for their help with data scoring.     

The effects of polydrug use with and without cocaine on mother-infant interaction at 3 and 6 months

The face-to-face interactions of 43 polydrug-with-cocaine-using mothers and their infants at 3 and 6 months were compared to 17 non-cocaine-but other-drug-using mothers and 21 mothers who used no drugs during their pregnancy. Coders blind to mothers' drug use status scored 3 min of face-to-face interactions for 16 measures of maternal and infant interactive behaviors. A principal component of 7 behaviors formed a measure of maternal attentiveness; a principal component of 5 behaviors formed a measure of mother-infant dyadic organization; and a principal component of 4 behaviors formed a measure of infant readiness to interact. A measure of maternal interruption was computed as the mean standard score of 3 additional interruptive behaviors. At 3 and 6 months, polydrug-with-cocaine-using mothers were less attentive to interactions, and polydrug-with-cocaine-using mothers and their infants engaged in fewer dyadic interactions than either non-cocaine or non-drug-using mothers. Compared to 3 months, polydrug-with-cocaine-using mothers at 6 months were less attentive to interactions and more frequently interrupted interactions by looking away, redirecting the infant, or withdrawing, whereas non-cocaine-using and non-drug- using mothers showed no change or an improvement in attentiveness to interactions and a decrease in interruptions. No differences emerged in the interactive behaviors of the infants of polydrug- with-cocaine-using, non-cocaine-using, or non-drug-using mothers. Cocaine use represents a significant risk for diminished parental attentiveness and responsiveness to infants and for diminished interactiveness in infants.     

Computational and reasoning abilities in arithmetic: Cross-generational change in China and the United States

A Chinese advantage over Americans was found for economically relevant computational and reasoning abilities in arithmetic for groups of 6th- and 12th-grade students matched or equated on general intelligence. No cross-national difference for computational or reasoning abilities was found for samples of older (60- to 80-year-old) Chinese and American adults equated on general intelligence. The pattern of change in arithmetical competencies across cohorts suggests that the Chinese advantage in 6th and 12th grade is due to a cross-generational decline in competencies in the United States and a cross-generational improvement in China.     

What is the pronunciation for -ough and the spelling for /u/? A database for computing feedforward and feedback consistency in English

Recent studies suggest that performance attendant on visual word perception is affected not only by feedforward inconsistency (i.e., multiple ways to pronounce a spelling) but also by feedback inconsistency (i.e., multiple ways to spell a pronunciation). In the present study, we provide a statistical analysis of these types of inconsistency for all monosyllabic English words. This database can be used as a tool for controlling, selecting, and constructing stimulus materials for psycholinguistic and neuropsychological research. Such large-scale statistical analyses are necessary devices for developing metrics of inconsistency, for generating hypotheses for psycholinguistic experiments, and for building models of word perception, speech perception, and spelling.     

Spline smoothing with model-based penalties

Nonparametric regression techniques, which estimate functions directly from noisy data rather than relying on specific parametric models, now play a central role in statistical analysis. We can improve the efficiency and other aspects of a nonparametric curve estimate by using prior knowledge about general features of the curve in the smoothing process. Spline smoothing is extended in this paper to express this prior knowledge in the form of a linear differential operator that annihilates a specified parametric model for the data. Roughness in the fitted function is defined in terms of the integrated square of this operator applied to the fitted function. A fastO(n) algorithm is outlined for this smart smoothing process. Illustrations are provided of where this technique proves useful.     

Internalizing and externalizing characteristics of sexually and/or physically abused children

This study evaluates the behavioral consequences of childhood abuse (sexual, physical, or both), with particular focus on prevalence of posttraumatic stress disorder (PTSD). Three abuse type groups and nonabused controls were contrasted on behavioral rating scales and on structured psychiatric interview data. The participants (109 abused children and 16 normal control children) were recruited from Arkansas Children’s Hospital and local agencies for abused children. As expected, proportionately more females than males were sexually abused. Overall, males were rated as more disturbed than females. Type of abuse did not consistently influence behavioral ratings. Externalizing scores were significantly higher than internalizing scores in all abused groups. PTSD was diagnosed in 50% of the abused children, with a higher rate for boys who had been sexually abused as opposed to physically abused only (58% versus 13%). The most frequent comorbid condition with PTSD was Separation Anxiety. Sexually abused boys were hospitalized for psychiatric treatment at a higher rate than were other abused children.