The acquisition of bimanual coordination is mediated by anisotropic coupling between the hands

The present study was designed to test two predictions from the coupled oscillator model of multifrequency coordination. First, it was predicted that multifrequency tasks that match the inherent manual asymmetry (i.e., the preferred hand assigned to the faster tempo) would be easier to learn than tasks that do not match the inherent dynamics (i.e., the non-preferred hand assigned to the faster tempo). Second, in the latter case acquisition of the multifrequency coordination would involve a reorganisation of the coupling dynamics such that the faster hand would exert a greater influence on the slower hand than vice versa. Sixteen right-handed volunteers received extensive training on a 2:1 coordination pattern involving a bimanual forearm pronation-supination task. Participants were randomly assigned to one of two groups: 1L:2R in which the preferred right hand performed the higher frequency, or 2L:1R in which the non-preferred left hand performed the higher frequency. The dynamic stability of the patterns was assessed by the ability of participants to maintain the coordination pattern as movement frequency was increased. Changes in the directional coupling between the hands was assessed by transition pathways and lead-lag relationship evident in a 1:1 anti-phase frequency-scaled coordination task performed prior to and following three practice sessions of the 2:1 task. The predicted differential stability between the multifrequency patterns was evident in the initial acquisition sessions but by the end of training the two patterns evidenced equivalent stability. Unexpectedly, for both groups the fast hand displayed greater variability in amplitude and movement frequency than the slow hand perhaps reflecting anchoring afforded to the slow hand by synchronising movement endpoints with the auditory pacing metronome. Analysis of pre- to post-training changes to the coupling dynamics in the 1:1 anti-phase task support the hypothesis that acquisition of the 2L:1R pattern involved reorganisation of the inherent dynamics.     

A basis for bias in geographical judgments

To determine why North Americans tend to locate European cities south of North American cities at similar latitudes (Tversky, 1981), we had observers provide bearing estimates between cities in the U.S. and Europe. Earlier research using latitude estimates of these cities has indicated that each continent has several subjective regions (Friedman & Brown, 2000a). Participants judged cities from two subjectively northern regions (Milwaukee-Munich), two subjectively southern regions (Memphis-Lisbon), and the two "crossed" regions (Albuquerque-Geneva; Minneapolis-Rome). Estimates were biased only when cities from the subjectively northern regions of North America were paired with cities from the subjectively southern region of Europe. In contrast to the view that biases are derived from distorted or aligned map-like representations, the data provide evidence that the subjective representation of global geography is principally categorical. Biases in numerical location estimates of individual cities and in bearing estimates between city pairs are derived from plausible reasoning processes operating on the same categorical representations.     

Reply to Schumm's argument that ending the gay ban will morally "injure" some service members

Schumm does not explain why moral injuries that would ensue from serving alongside peers who utter the words "I am gay" warrant protection in federal law.     

Dimensionality of the Beck Youth Inventories With Child Psychiatric Outpatients

The Anxiety, Depression, Anger, Disruptive Behavior, and Self-Concept Inventories of the Beck Youth Inventories of Emotional and Social Impairment (J. S. Beck, A. S. Beck, & J. Jolly, 2001) were administered to 150 female and 150 male outpatients who were 7–12 years old and matched by sex as to whether they were diagnosed with anxiety, mood, adjustment, or attention-deficit and disruptive behavior disorders to determine whether each inventory represented distinct symptom dimensions. Horns parallel analyses (J. L. Horn, 1965) found that the Anxiety, Depression, and Disruptive Behavior Inventories were unidimensional, but that the Anger and Self-Concept Inventories were each composed of two underlying dimensions. Iterated principal-factor analyses indicated that the Anger Inventory represented Affective and Cognitive dimensions, whereas the Self-concept Inventory reflected Self-Esteem and Competency dimensions. However, the overall pattern of results was discussed as supporting the current practice of scoring each inventory as a summative scale for clinical assessment purposes.     

Response speeding mediates the contributions of cue familiarity and target retrievability to metamnemonic judgments

Metamnemonic judgments are influenced by the retrievability of the target memory in question, but also by the familiarity of the cue used to elicit such judgments. However, there have been few suggestions as to what factors mediate the influence of these different sources of information on metamnemonic judgments. In this experiment, I examined the interactions between prediction time pressure and variables that promote either cue familiarity or target retrievability. The data reveal that target retrievability plays a larger role than does cue familiarity in fostering predictions of future recall made under unpressured conditions, but that cue familiarity influences predictions that are speeded. This pattern is interpreted by analogy with recognition memory: Mnemonic evidence based on familiarity is more impervious to the demands of time pressure than are the products of deliberative retrieval. Several explanations for this effect are suggested.     

A cognitive tool to diagnose predominantly inattentive ADHD behavior

Poor performance on tests of reading comprehension could be the result of weak word-recognition skills, inconsistent attention (ADD), or a combination of the two. Identifying the source of the reading disability (RD) reliably has been difficult because inconsistent attention interferes with reading and weak word recognition skill makes attention wander. The situation is further complicated by the fact that there are no objective diagnostic tests for ADD (Breggin, 1998; Diller, 1998). We proposed a new model of differential diagnosis of ADHD-I/RD and field-tested its utility in two studies. The new diagnostic procedure utilizes intra-individual differences seen in the performance of at-risk learners on tasks related to reading that vary in the degree of sustained attention required for successful performance. The hypothesis is that children whose attention is inconsistent would perform more poorly on tests such as listening comprehension, which require sustained attention, than on tests such as reading comprehension, which are more tolerant of inattention. Such differences will not be seen in the test scores of children who have only a reading disability because their performance on reading tests is determined more by the difficulty level of the tests than by the sensitivity of the tests to attention. The validity of this new model was evaluated by determining the relationship between differences seen in the scores of tests that differ in their attention requirement and the degree of inconsistency in sustained attention as measured by Conners' CPT. The results of the two studies indicate this to be a viable approach. The results of the second study are presented in this report.     

A multiple-goal, multilevel model of feedback effects on the regulation of individual and team performance

When working as a member of a team, individuals must make decisions concerning the allocation of resources (e.g., effort) toward individual goals and team goals. As a result, individual and team goals, and feedback related to progress toward these goals, should be potent levers for affecting resource allocation decisions. This research develops a multilevel, multiple-goal model of individual and team regulatory processes that affect the allocation of resources across individual and team goals resulting in individual and team performance. On the basis of this model, predictions concerning the impact of individual and team performance feedback are examined empirically to evaluate the model and to understand the influence of feedback on regulatory processes and resource allocation. Two hundred thirty-seven participants were randomly formed into 79 teams of 3 that performed a simulated radar task that required teamwork. Results support the model and the predicted role of feedback in affecting the allocation of resources when individuals strive to accomplish both individual and team goals.     

Temporal coding in conditioned inhibition: analysis of associative structure of inhibition

Two experiments with rats as subjects were conducted to investigate the associative structure of temporal control of conditioned inhibition through posttraining manipulation of the training excitor-unconditioned stimulus (US) temporal relationship. Experiment 1 found that following simultaneous Pavlovian inhibition training (i.e., A --> US/XA-no US) in which a conditioned stimulus (CS A) was established as a delay excitor, maximal inhibition was observed on a summation test when CS X was compounded with a delay transfer CS. Furthermore, posttraining shifts in the A-US temporal relationship from delay to trace resulted in maximal inhibition of a trace transfer CS. Experiment 2 found complementary results to Experiment 1 with an A-US posttraining shift from serial to simultaneous. These results suggest that temporal control of inhibition is mediated by the training excitor-US temporal relationship.