Psychology, Experimental

Source monitoring capabilities in children four, five, and six years of age classified along high and low inhibition abilities were investigated in three different conditions of source monitoring: reality monitoring, internal source monitoring, and external source monitoring. Specifically, children's misattribution errors in internal and reality source monitoring conditions with regard to their inhibition status was investigated. During one testing session, children were randomly assigned to the three source monitoring conditions and invited to participate in puzzle completion tasks. In the reality source monitoring condition, children and experimenters took turns placing the puzzle pieces on a puzzle board. In the internal source monitoring condition, children were requested to actually place half of the puzzle pieces of their choice and to pretend to place the other half on the board. In the external source monitoring condition, children were requested to watch two different experimenters taking turns placing puzzle pieces on the board. After a short retention interval, children were surprised with a puzzle piece recall test. Children's inhibition abilities were assessed with three different inhibition tasks during a subsequent testing session and consisted of a tapping test, Simon Says test, and response compatibility test. Median splits determined children's inhibition abilities as either high (efficient) or low (inefficient). Sets of analysis of variance tests compared participants' general recall performance abilities among the three conditions of source monitoring and evaluated participants' reality and internal performance abilities with regard to inhibition status. The first set of analyses indicated that children made the most recall errors in the external source monitoring condition and the fewest in the reality source monitoring condition. The second set of analyses revealed that 4-year-old boys, compared to 5- and 6-year-old boys, committed more errors toward the misattribution bias in the internal condition, while 4-year-old girls, compared to 5- and 6-year-old girls, committed more errors against the bias. The third set of analyses supported the hypothesis that inefficient inhibitors on the tapping task committed more errors toward the misattribution bias in the internal source monitoring condition than those in the reality condition.

Social context effects on young children's sex-typing were examined in two studies. In Study 1 sex-typed toy choices of 139 children aged 4 to 8 were assessed first for a solitary-play context, and then for three social contexts distinguished as to friendship status of a specified play partner (represented by a photo): best friend, acquaintance, and an unfamiliar peer. For each context, children selected preferred toys from photographs of a neutral toy paired with either a same- or opposite-sex toy. Results indicated social context effects for girls but not boys, in that girls tended to display more sex-typed toy choices in the solitary and best-friend than in the acquaintance or unfamiliar peer contexts. In general, however, girls approached same-sex toys less than boys, while both sexes avoided opposite-sex toys to a similar extent. In Study 2 subjects were 68 children aged 4 to 7. They were asked to imitate videotaped masculine, feminine, and neutral actions of a hand puppet. For different children, the puppet was designated (by name and photo display) as either a best friend or acquaintance, and it engaged in the sex-typed activities with either gender-congruent or incongruent affect (happy for same-sex actions and sad for opposite-sex actions, or the reverse). Friendship status and gender-affect congruency effects which varied with age level were evident for several memory measures. Incongruency promoted accurate imitative matching for the acquaintance context in younger children, and for the best-friend context in older children. In addition, best-friends' feminine actions were imitated more accurately than their masculine or neutral actions. Subject age and sex also interacted with activity gender type and gender-affect congruency to influence peer affect recall, with poorer recall of feminine-activity affect by boys in the incongruent condition. While social context had little impact upon boys' reported affect, girls' enjoyment was lower for masculine activity imitation in the best-friend congruent-affect condition. Overall, the two studies demonstrate that young children's gendered behaviors show considerable sensitivity to social context factors, and indicate the important influence of affective factors in early sex-typing.

This work examines contextual influences on processing of linguistic stimuli. The traditional (symbolic) models of context influences are reviewed and their shortcomings pointed out. The dynamical approach, recently emerging in the area of behavioral sciences, is suggested as a viable alternative. Two studies follow. In the first one we use the case of perception of ambiguous sentences to show that perception of linguistic stimuli is the outcome of an underlying dynamical process. Thus it may be better described in dynamical terms, employing notions such as multistability and differential coherence of patterns, than in the traditional, symbolic framework. The second study is an on-line investigation of contextual adaptation. We studied general category names embedded in neutral or biasing sentential contexts. The results obtained indicate that the initial lexical access is context independent. The relative availability of particular members of category suggests that the initial state is best captured by a multistable representation, which may be essential for the flexibility of linguistic processing. Contextual adaptation seems to occur later in the unfolding sentence. A more detailed investigation into the timing and nature of contextual adaptation suggests that this adaptation takes the form of rapid reorganization of conceptual information rather than just facilitation of relevant category members. The results of the studies presented have implications both for dynamical and psycholinguistic approaches. The main implication for the dynamical approach is the importance of using on-line methods in studies of perception. Dynamical studies that use off-line methods perhaps miss an important stage of processing: a transition from locally invariant to contextually congruent organization of information. For psycholinguistics the characterization of language processing as pattern formation has at least three major advantages: (1) capturing the timing of the processes allows for including distinctions between fast/slow, linear/nonlinear processing, (2) conceptualization of the initially available lexical information as a constraint on possible meanings rather than meaning itself allows for accounting for apparently contradictory psycholinguistic data, (3) adding the dimension of stability of the patterns generated during language processing makes possible new predictions regarding speed and variability of performance on various psycholinguistic tasks.

This study investigated figure/ground segregation based on both common movement ("common fate" for the Gestaltists) and perceived stationarity (nonmovement), i.e., a figure presented in two different locations and embedded in noise either appeared moving or stationary when it was perceptually segregated. The effect of differences in the duration of a figure (a three-dot line) in each location was studied in Experiment 1. A figure was presented for the same duration (duty cycle = 0.50) or for different durations (duty cycles of 0.25 and 0.75) in each location (the Temporal Symmetry and Asymmetry conditions, respectively). The figure always appeared to move when it was segregated from background noise (motion-based figure/ground segregation) for Temporal Symmetry. In contrast, figure/ground segregation could be based on the perception of stationarity as well as motion for Temporal Asymmetry. Thresholds (50%) were measured as the number of added noise dots that resulted in perceiving motion of the figure and for perceiving the figure itself. Additional results demonstrated that the figure was perceived in the location having the.75 duty cycle. It is proposed that higher energy in the 0-Hz frequency component in this location results in stationarity-based figure/ground segregation, whereas higher energy in time-varying frequency components underlies motion-based figure/ground segregation. In Experiment 2, hysteresis was observed in the Temporal Asymmetry condition in the transitions between perceived motion and stationarity and between perceived stationarity and noise. In the Temporal Symmetry condition, hysteresis was observed in the transition between perceived motion and noise. The presence of hysteresis indicates that perceived stationarity in the Temporal Asymmetry condition is not due to insufficient activation of motion detectors, but is a stable perceptual state based on mechanisms that are sensitive to 0-Hz energy and compete with motion-detecting mechanisms sensitive to energy in time-varying frequency components. Judgments of motion direction in Experiment 3 provided tentative evidence that both duration of the briefer frame and duty cycle influence perceived motion.

This project comprises a series of experiments investigating the role of prosody--the timing and intonation of an utterance--in syntactic disambiguation. Acoustic analyses isolated two parameters--main-clause verb segment and pause durations, and the pitch contour over the verb and the following phrase--that reliably predicted syntactic structure in two sets of temporarily ambiguous sentences. The manipulation of one of these parameters--verb and pause duration--resulted in increased processing load over the disambiguating region of sentences temporarily ambiguous between a direct object and an embedded clause syntactic structure (e.g., "John knew the answer by heart" vs. "John knew the answer was correct"). Also, differences in the prosodic contours associated with temporarily ambiguous "filler-gap" sentences determined whether or not a gap was posited during on-line sentence processing. These findings suggest that prosodic information is used early, perhaps immediately, to make informed on-line parsing decisions and support a model of sentence processing in which both lexical and prosodic information interact on-line to generate the syntactic representation of an utterance.

This experiment examined the impact of knowledge base and declarative metamemory knowledge on the acquisition of a reading comprehension strategy. Fourth- and fifth-grade boys who were poor readers were tested for their baseball knowledge and declarative metamemory knowledge. Those boys who were designated as baseball experts were included in the experiment. The boys were pretested for strategy use and comprehension, received two days of training in the use of the strategy, and then were later tested twice: once within 3 days of training, then again 2-3 weeks later. The boys were divided into four groups. The T-BB (training, baseball stories) group received training in the use of the strategy using baseball stories. The T-NB (training, nonbaseball) group received equivalent training but used nonbaseball sports stories. Two control groups received equal time with the experimenter and equal reading practice with either baseball or nonbaseball stories, but were not taught the strategy. Because there were no differences in the level of strategy use or comprehension of the two control groups they were later combined into one control group. The target strategy was the asking of "why" questions in response to facts in the text. The asking of "why" questions has been hypothesized to activate relevant schema which are then used to facilitate the memorization of new material. Poor readers often do not utilize their existing knowledge to process new information. Children who received training with baseball stories (T-BB) demonstrated greater strategy acquisition than both other groups when tested both 2-3 days later (near posttest), and also when tested 2-3 weeks later (distant posttest). Group membership (T-BB, T-NB, or Control) did not impact free or cued recall. Declarative metacognitive knowledge impacted strategy acquisition and recall. Higher-metacognitive children asked more "why" questions than did lower-metacognitive children, demonstrated greater free recall, and were more likely to benefit from the strategy training in terms of cued recall. An unexpected finding was that children in the T-BB group asked more "why" questions in response to nonbaseball rather than baseball stories. This was discussed in terms of an appropriate increase of monitoring by the children who were trained within their area of expertise. Overall, children recalled more of the baseball than the nonbaseball stories. While both training groups had significant correlations between strategy use and free recall at the distant posttest, indicating a recall benefit associated with strategy use, only T-BB children had significant correlations at the near posttest.

The dynamics of pattern formation and change are studied in a complex, multicomponent system, specifically the arms and legs of human subjects. Previous studies (Kelso & Jeka, in press) have demonstrated novel features in the coordinative dynamics of an arm-leg pair, including: (1) differential stability of coordinative modes produced by limbs moving in the same (S-mode) versus different (D-mode) directions; (2) a slow drift in relative phase preceding transitions from the D- to the S-mode; (3) preferred transition routes between patterns; and (4) spontaneous emergence of non 1:1 frequency- and phase-locked patterns, in addition to periods of relative coordination. These phenomena have been encompassed theoretically in a model of coupled oscillators which includes a symmetry-breaking term to represent the difference in the uncoupled frequencies of the arm and leg (Kelso et al., 1990). To test predictions of the (Kelso et al., 1990) model, the first of two studies was aimed at whether manipulation of the inherent biophysical differences between the arm and leg, through inertial loading, would be reflected in their coordinative dynamics. The results showed that loading the leg led to the highest percentage of: (1) D- to S-mode transitions in the down direction (i.e., with decreasing values of relative phase); and (2) transitions to phase wandering. Loading the arm led to: (1) an approximately equal number of transitions in either the up or down direction; and (2) very few transitions to phase wandering. The conclusion was that adding weight to the arm or leg was influential in minimizing or enhancing the coordinative asymmetry, respectively. A second study used the same loading conditions as Experiment 1 within a perturbation paradigm to study possible differences in relaxation time and perturbation-induced transitions, as additional measures of the asymmetry of the coordinative dynamics. Relaxation time and perturbation-induced transition pathways showed no effects of inertial loading. Pretransition relative phase showed a steady decrease when the leg was loaded and very little drift in the arm load condition. Pretransition relaxation time increased systematically with required frequency and relative phase variability, but only with perturbations in the up direction (i.e., increasing values of relative phase). These effects were consistent with model predictions and showed that asymmetric dynamics characterized the coordinative patterns of anatomically different components.

This research explored group differences according to giftedness and achievement in the acquisition and generalization of a strategy for solving analogies. A distinction was made between proximal and distal transfer, with the latter expected to differentiate between gifted and nongifted cognition. Underachievement in gifted children was expected to reflect either strategy deficits, or the absence of performance differences in a theoretically important cognitive skill (generalization) between the so-called "underachieving" gifted and other bright but nongifted children. 162 seventh and eighth graders were selected according to intelligence and achievement scores, academic program, and teacher opinion, and assigned to one of four groups: high achieving gifted, underachieving gifted, high achieving nongifted, and average achieving nongifted. Each child was seen individually for two sessions, and solved a total of five sets of ten multiple-choice analogies. The first session included two baseline trials (one verbal and one figural set), followed by training in the use of a strategy. The second session included a proximal transfer trial (same analogy type as used at training), and a distal transfer trial (analogies from the never-trained domain). All analogies were solved orally, and strategy use was determined from audio-recordings. The results showed that the high achieving gifted children were more spontaneously, frequently, and successfully strategic than the other three groups, as well as most accurate following the decision not to use a strategy. They were also the only group to show performance increases at distal transfer. In terms of gifted underachievement, there was evidence to support both hypotheses. The underachieving gifted children showed qualitative deficits in strategic functioning as compared to their high achieving gifted counterparts, and also tended to "look" like the high achieving nongifted group in their patterns of performance. These results were discussed in terms of the likelihood of subgroups of underachieving gifted children, and their implications for education and the identification of giftedness.

This study examined the hypothesis that both exposure to reading materials in the home and intrinsic motivation to read mediate the relationship between socioeconomic status and reading comprehension skills in adolescents. Data were derived from the Program for International Student Assessment 2000 dataset (PISA 2000). Six countries out of forty-three were chosen on the basis of country-level SES: two from the bottom 25th percentile (Thailand, Mexico), two at the 50th percentile (Austria, France), and two at the 75th percentile (Norway, United States). Data analysis was conducted on a total of 27,351 participants and 823 schools. Hierarchical linear modeling (HLM) analyses were conducted to examine predictors of reading comprehension skills. Follow-up analyses using logistic regression were conducted to predict group membership (i.e., poor vs. normal readers). Results support the idea that exposure to reading materials in the home mediates the relationship between SES and reading comprehension skills at the child level, regardless of the overall economic state of the country. This relationship did not hold when predicting at the school level. Intrinsic motivation to read was consistently a poor predictor.

The motion of an object may be perceived based on a change in location of either its surface or edges. By isolating the luminance changes produced by a moving object from the physical displacement of its surface and edges, it was found that a static object appears to move when the luminance changes are restricted to a narrow area adjacent to it. Therefore, changes in the luminance contrast of edges are sufficient for the perception of object motion. However, the existence of different motion signals based on luminance changes of edges and surfaces was confirmed by the occurrence of different motion percepts for the same stimulus configuration. As the width of the region which changed in luminance was increased, edge-based motion percepts were replaced by a surface-based motion percept. This study was primarily concerned with the interaction between the mechanisms that signal edge-based motion and surface-based motion. It was found that surface-based motion mechanisms inhibit edge-based motion mechanisms, even when the different motion patterns were in the same direction. Modulating the effects of this inhibition was facilitation between edge-based motion mechanisms when two sliding-edge motions were possible in the same direction. Less facilitation, and possibly inhibition, occurred when the sliding-edge motions were in the opposite compared with the same direction. Finally, there was even greater inhibition from surface-based motion mechanisms ado edge-based motion mechanisms when the different motion patterns were specified in the opposite compared with the same direction. It is concluded that much of the observed inhibition results from high-level perceptual processes that distinguish between whether particular luminance changes are caused by the disappearance and reappearance of one object or by the local movement of multiple objects. Assuming that jumping-object motion is perceived naturally when there is an interruption in the visual processing of a moving object, such as with blinking, the nature of the inhibition would serve to, reduce the inappropriate perception of motion for ether objects adjacent to the previously and newly occupied locations of the moving object.