Influence of Passive Rotation on the Intonation of the Voice

Seventy-two subjects were randomly drawn across grades K-2 and administered an instrument designed to measure developmental skills within seven skill area categories. A three-way ANOVA, fixed effects model, was used for data analysis. Subjects were blocked by eye color, sex, and grade level for the purpose of investigating the relationship between eye color and sex to self-paced and reactive behaviors. Significant differences were obtained on the main effect of eye color in five of the seven categories examined. There were three significant first order interactions (sex × eye color) and one three-way interaction. The findings support the hypothesis of Worthy that eye color is a dependable predictor of subjects' general behavioral competency area (self-paced or reactive) and adds considerable support for his thesis that self-paced and reactive behaviors are to some degree inherited.     

The Coding of Location

One prediction of the recent target hypothesis for movement control (MacNeilage, 1970; Russell, 1976) holds that location reproduction is not solely dependent upon stored kinesthetic information. Three experiments were performed to test this prediction by requiring the subject to reproduce the location with the limb opposite to the one used for criterion production. This switched-limb procedure was assumed to force the subject to rely upon more abstract information rather than the kinesthetic cues of the criterion movement. With movement direction invariant, switched-limb reproduction was equal to same-limb reproduction. The alteration of movement direction hampered switched-limb reproduction but same-limb reproduction was not greatly affected. These findings gave some support to the target hypothesis but suggested that the context of the movement may affect the potency of the location code. Implications of the switched-limb technique for future research were briefly discussed.     

Memory Drum Theory

Two experiments investigated the memory drum theory’s prediction (Henry & Rogers, 1960) that simple reaction time (SRT) increased with the complexity of the response to be initiated. Experiment 1 (N = 9) matched the Experiment 1, Group 1, SRT condition described by Henry and Rogers. Results of Experiment 1 replicated those of Henry and Rogers and indicated that the memory drum theory’s prediction of increased SRT as a function of increased complexity of response was tenable. Experiment 2 (N = 11) tested the effects of anatomical unit, extent, and target size on SRT, premotor time, and motor time. The results supported the contention that alternative explanations for SRT were possible. With complexity constant, increases in anatomical unit lead to increases in SRT, but only in the motor time component which indicated electromechanical rather than neuromotor program delays. It is proposed that the increased motor time could be explained by peripheral events such as the duration maximum torque must be applied by the agonist muscle(s) to generate the angular acceleration required to initiate rapid movement. SRT, premotor time, and motor time increased when target size was reduced from 6.35 cm to .79 cm. The increased premotor time could be a function of the determining of new equilibrium points for the elbow joint during response initiation. No effects on SRT were observed for extent.     

Work and Rest Variables in the Acquisition of Psychomotor Tracking Skill

College students (75 men, 75 women) matched in preliminary performance of 100 sec on the rotary pursuit apparatus were randomly assigned to five experimental groups. Their work/rest ratios, measured in seconds, were: 20/20, 30/30, 60/60, 90/90,120/120. All subjects received 30 min of total practice time after the matching trial. There was a significant practice effect and a significant practice x conditions interaction, but no main effect due to the cycles’ length or number. The decay rate of reactive inhibition (lr) is probably independent of its prior growth level; hence postrest residual lr is proportional to prerest accumulation. Partly because they generated lr in hypothetically greater amounts, women were significantly less proficient on the average than men, and sex interacted with practice. Although males had higher initial and final levels of ability than females, the two sexes’ acquisition curves showed the same rate parameters in our mathematical model.     

Target prototypicality moderates racial bias in the decision to shoot

Research shows that target race can influence the decision to shoot armed and unarmed Black and White males (e.g., Correll, Park, Judd, & Wittenbrink, 2002). To date, however, research has only examined category level effects by comparing average responses to Blacks and Whites. The current studies investigated whether target prototypicality influences the decision to shoot above and beyond the effect of race. Here, we replicated racial bias in shoot decisions and demonstrated that bias was moderated by target prototypicality. As target prototypicality increased, participants showed greater racial bias. Further, when targets were unprototypic, racial bias reversed (e.g., participants mistakenly shot more unarmed Whites than Blacks). Study 2 examined whether these effects were observed among police officers. Although police showed no racial bias on average, target prototypicality significantly influenced judgments. Across both studies, sensitivity to variability in Whites' prototypicality drove these effects, while variation in Black prototypicality did not affect participants' decisions.     

The representation of predictive force control and internal forward models: evidence from lesion studies and brain imaging

Force control on the basis of prediction avoids time delays from sensory feedback during motor performance. Thus, self-produced loads arising from gravitational and inertial forces during object manipulation can be compensated for by simultaneous anticipatory changes in grip force. It has been suggested that internal forward models predict the consequences of our movements, so that grip force can be programmed in anticipation of movement-induced loads. The cerebellum has been proposed as the anatomical correlate of such internal models. Here, we present behavioural data from patients with cerebellar damage and data from brain imaging in healthy subjects further elucidating the role of the cerebellum in predictive force control. Patients with cerebellar damage exhibited clear deficits in the coupling between grip force and load. A positron-emission-tomography (PET) paradigm that separated the process of the grip force/load coupling from the isolated production of similar grip forces and loads was developed. Interaction and conjunction analyses revealed a strong activation peak in the ipsilateral posterior cerebellum particularly devoted to the predictive coupling between grip force and load. Both approaches clearly demonstrate that the cerebellum plays a major role in force prediction that cannot be compensated for by other sensorimotor structures in case of cerebellar disease. However, evidence suggests that also extra-cerebellar structures may significantly contribute to predictive force control: (1) grip force/load coupling may also be impaired after cerebral and peripheral sensorimotor lesions, (2) a coupling-related activation outside the cerebellum was observed in our PET study, and (3) the scaling of the grip force level and the dynamic grip force coupling are dissociable aspects of grip force control.     

Dissociation of Bimanual Responses With the Simon Effect: On the Nonunitization of Bimanual Responses

The authors examined whether responses of the 2 hands were completely unitized when participants (N = 36) produced bimanual responses to lateralized targets in a Simon-type paradigm. Their primary aim was to investigate whether lateralized stimuli differentially influence the response dynamics of the 2 hands. Simon effects were obtained in reaction time and force; components of the bimanual response by the hand on the same side as the lateralized stimulus were more forceful than were those of the other hand. Also, Simon effects were larger when the lateralized target appeared alone than when it was accompanied by a distractor on the other side of the display. Finally, responses of the 2 hands were correlated most strongly when stimulus displays were symmetrical. The authors conclude that bimanual responses are strongly coupled, but not perfectly so.     

Delinquent Development in Dutch Childhood Arrestees: Developmental Trajectories,Risk Factors and Co-morbidity with Adverse Outcomes during Adolescence

Heterogeneity of re-offending patterns was studied in a group of 287 male early onset offenders who were first arrested before age 12. By combining data on the frequency and severity of offending as registered by the police over a 5-year follow-up period, three delinquent trajectories were identified; low, escalating, and high level re-offenders. Predicting group membership by individual and environmental characteristics known to the police at the time of the first arrest proved difficult. Compared to low level re-offenders, escalators were older and more often came from disadvantaged neighborhoods. High level re-offenders were also older at onset, more often had a non-Western ethnic background, and initially committed more vandalism. Furthermore, at the first police encounter, the police reacted more severely towards those who later became high level re-offenders. Finally, high and escalating re-offenders more often had other adverse outcomes, such as criminal victimization and Child Welfare Agency involvement.

Jeopardy Not Bonus Status for African American Women in the Work Force: Why Does the Myth of Advantage Persist?

African American women in the United States have a long history of employment outside of their homes. Their experiences are unique from other groups of majority and minority men and women due to the interaction of race, gender, and class. Despite long-standing and continuing struggles against discrimination, harassment, low pay, tokenism, and stereotypes, a myth that African American women enjoy a bonus or advantaged status in the work force has developed and persisted. In this article, Black women's work force experiences are examined from a social constructionist framework, misperceptions of Black women are critiqued, explanations are developed that explain the unique status of African American women and recommendations are proposed to eradicate the discrimination and marginal status that Black women have endured in the work force.     

准备状态对反应抑制的影响

从事件因素和时间因素两个方面探讨了准备状态对反应抑制的影响。事件准备可降低反应模式的不确定性 ,而时间准备则与降低反应时间的不确定性有关。线索、反应概率以及刺激呈现时间等因素不仅导致反应时间出现变化 ,还可引起反应力、心跳间期以及LRP和CNV等脑电指标发生变化。传统的反应抑制研究以反应时为指标 ,不能揭示反应抑制的内部过程 ,而心理生理学方法能弥补这一缺陷。生理指标与行为指标的结合 ,以及生理指标之间的结合 ,可更有效地探讨准备状态对反应抑制的效应。