Coordinating Actions

The motor system composes complex actions by combining simpler submovements. This presumably involves sharing information about the progress of one submovement with the centres controlling another submovement, to ensure that the second happens in an appropriate relation to the first. This process is called coordination. In this paper Idiscuss evidence that coordinating actions indeed involves an active process of sharing information about the current state of movements. Coordination appears to be qualitatively different from the process of reacting to external stimuli. This may reflect the importance of predictive representations in coordination. Finally, the processes underlying coordination appear to be organized in a response-specific fashion, as a number of relatively independent circuits. The development and tuning of these circuits may, in part, be what makes an action "skilled".     

BEWILDERMENT AND THEREAFTER: Some Reflections in Response to Lee Yearley

The following reflections were originally an oral response to issues raised in Lee Yearley's presentation in May 2009 at Harvard Divinity School. As written here, they follow upon his oral and now written comments, highlighting key issues and points for development, drawing on this respondent's expertise in comparative and Hindu studies.     

Serial pattern learning by event observation.

Serial pattern learning was investigated in a variation of the task introduced by Nissen and Bullemer (1987). We presented an asterisk at 1 of 4 spatial locations on each trial, and Ss either responded with a keypress or observed the event. The first 4 blocks contained 10 repetitions of a 10- or 16-element pattern, and the 5th block contained a random sequence. The difference in response time on the 5th random block and the previous patterned block served as an indirect measure of pattern learning. A direct measure was obtained in a final test block in which Ss predicted the next asterisk position. Equivalent learning occurred for responding and observing with indirect measures, but observation was superior with direct measures. These findings indicate that knowledge of serial order can develop through simple perceptual experience, and this is more available to deliberate recall than is knowledge acquired while responding.     

A cascade of rejection and appearance preoccupation: Adolescents’ body dysmorphic symptoms and appearance rejection sensitivity over 4 years

Adolescence is a high-risk period for body image disturbance and appearance concerns. In a cascade model, we examined interrelations of body dysmorphic symptoms (BDS) with appearance rejection sensitivity (ARS) and tested gender moderation. Participants were 397 Australian adolescents (T1 Mage = 11.7, SD = 0.91; 56% girls) who completed six surveys over 4 years. In a random-intercept cross-lag model, two (of five possible) paths showed ARS predicted higher subsequent BDS, and three (of five possible) paths showed BDS predicted higher subsequent ARS. Girls reported more BDS and ARS than boys, and random intercepts of BDS and ARS were correlated with the correlation stronger in girls than boys. Cross-lag BDD-ARS associations over the six waves were not significantly moderated by gender. Overall, girls are at higher risk of appearance concerns than boys, but BDD-ARS cascade effects do not differ between girls and boys.     

Hearing a Still-Ticking Bomb Argument: A Reply to Bufacchi and Arrigo

My aim in this paper is to demonstrate that the recent anti-Ticking Bomb argument offered by Bufacchi and Arrigo is unsuccessful. To adequately refute the Ticking Bomb strategy, I claim, requires carefully addressing both policy questions and questions involving exceptional conduct.