Rapid error correction during human arm movements: evidence for central monitoring

Studies were made of rapid error correction movements in eight subjects performing a visually guided tracking task involving flexion-extension movements about the elbow. Subjects were required to minimize reaction times in this two-choice task. Errors in initial movement direction occurred in about 3% of the trials. Error correction times (time from initiation to reversal of movement in incorrect direction) ranged from 30-150 ms. The first sing of correction of the error movement was a suppression of the electromyographic (EMG) activity in the muscle producing the error movement. This suppression started as early as 20-40 ms after the initiation of the error-related EMG activity and as much as 50 ms before any overt sign of limb movement. The correction of the error movement was also accompanied by an increase in the drive to the muscle which moved the arm in the correct direction. This increased activity always occurred after the initiation of the error movement. it is concluded that the first step in the error correction, suppression of drive to the muscle producing the error movement, cannot be based on information from the moving limb. It is thus suggested that this earliest response to the error movement is based on central monitoring of the commands for movement.     

The effect of microlevel and macrolevel signaling on learning with 360° videos

The application of 360° videos raised the attention of educators and researchers, as it appears to be an approachable option to mediate complete environments in educational settings. However, challenges emerge from the perspective of educational psychology. Learning irrelevant cognitive strains might be imposed because it is necessary to navigate through spherical material. However, these potential downsides could be compensated for using signaling techniques. In a two (macrolevel vs. no macrolevel signaling) × two (microlevel vs. no microlevel signaling) factorial between-subjects design plus control group, 215 fifth-and sixth-grade students will watch a 360° video about visual and behavioral characteristics of animals. Learning outcomes, cognitive load, disorientation, and presence will be investigated. It is expected that macrolevel signaling will enhance learning and presence and reduce cognitive load and disorientation. Microlevel signaling will have comparable advantages, but these effects will be more pronounced when macrolevel signaling is implemented.     

Ingroup Versus Outgroup Perceptions of the Characteristics of High-Risk Youth: Negative Stereotyping1

Adolescents tend to categorize themselves and their peers into discrete ingroups and outgroups. A comparison of ingroup versus outgroup perceptions of the characteristics of high-risk youth was investigated. Based on current stereotype research, we examined the perspective that outgroup members would hold a more extreme stereotype of high-risk youth compared to the perceptions of ingroup members. A total of 955 7th- and 10th-grade southern California adolescents completed a questionnaire regarding the characteristics of their own peer group and a high-risk group. Support was obtained for an extremity of judgement effect. Outgroup youth perceived that their high-risk peers engaged in fewer school and nonschool low-risk activities, more high-risk activities, and greater drug use than did ingroup members. Outgroup members also held perceptions of high-risk youth as less likely to hold a white-collar job than did the ingroup members. The perceptions that adolescents have of these groups may play major roles in their own social behavior. The implications of these results for future tobacco use prevention programs are considered.     

Grading the ‘cultural literacy’ project

The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.     

A call for a pluralist epistemological understanding in the assessment and evaluation of counselling

The authors outline and posit the futility of the 'paradigm war' between reductionistic/positivistic and phenomenological/naturalistic philosophies within counselling evaluation, pointing out that the notion of such competition is itself based on positivist thinking. They trace attempts at creating a 'truce' in the war based on strict demarcation of territory. They conclude that in the longer term more might be gained by accepting the veracity of both philosophies and creating a pluralist model which will be more fully equipped to evaluate the human process of counselling.     

Referenzsemantik in der Partnermodellierung

How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.