A Speeded Item Response Model with Gradual Process Change

An item response theory model for dealing with test speededness is proposed. The model consists of two random processes, a problem solving process and a random guessing process, with the random guessing gradually taking over from the problem solving process. The involved change point and change rate are considered random parameters in order to model examinee differences in both respects. The proposed model is evaluated on simulated data and in a case study. The research reported in this paper was supported by IAP P5/24 and GOA/2005/04, both awarded to Paul De Boeck and Iven Van Mechelen, and by IAP P6/03, awarded to Iven Van Mechelen. Yuri Goegebeur’s research was supported by a grant of the Danish Natural Science Research Council.     

Teleo‐functional constraints on preschool children's reasoning about living things

These studies explore the degree to which preschool children employ teleological‐functional reasoning – reasoning based on the assumption of function and design – when making inferences about animal behavior. Using a triad induction method, Study 1 examined whether a sensitivity to biological function would lead children to overlook overall similarity and instead attend to relevant functional cues (in the presence of overall dissimilarity), as a basis for generalizing behavioral properties to unfamiliar animals. It found that, between 3 and 4 years of age, children, with increasing consistency, attend to functional features rather than overall similarity when drawing inferences about animal behavior. Children's ability to describe the relevance of functional adaptations to animal behavior also increased with age. Study 2 explored whether Study 1 findings might result from stimulus biases in favor of the function‐based choice. It found that children's attention shifted from functional features to overall similarity when generalizing labels rather than behaviors with the same triads. These results are discussed in relation to the development of biological knowledge.     

Memory, Anaphora, and Content Preservation

Tyler Burge defends the idea that memory preserves beliefswith their justifications, so that memory's role in inferenceadds no new justificatory demands. Against Burge's view,Christensen and Kornblith argue that memory is reconstructiveand so introduces an element of a posteriori justificationinto every inference. I argue that Burge is right,memory does preserve content, but to defend this viewwe need to specify a preservative mechanism. Toward thatend, I develop the idea that there is something worthcalling anaphoric thinking, which preserves content inBurge's sense of ``content preservation.' I providea model on which anaphoric thought is a fundamentalfeature of cognitive architecture, consequentlyrejecting the idea that there are mental pronounsin a Language of Thought. Since preservativememory is a matter of anaphoric thinking, thereare limits on the analogy of memory and testimony.     

The Traditional Explanation for Resistance Versus Attitude Accessibility

This investigation compared the traditional explanation for the way inoculation confers resistance to influence with an alternative rationale for resistance based on attitude accessibility. Four hundred forty‐three participants took part in the investigation in four phases spanning 54 days. The combined multiple regression and structural equation modeling results suggest that the traditional and alternative explanations for the way that inoculation confers resistance involve separate processes; counterarguing and accessibility appear to be distinct tracks en route to resistance, but the two explanations also are overlapping processes in which elicited threat plays an integral role.     

Gender and developmental patterns of affect, belief, and behavior in simulated injury events

This study examined the hypothesis drawn from epidemiological data that beliefs and affective reactions of male second, fifth, and eighth graders, undergraduates, and adults in response to a series of four simulated bicycle collisions would show decreased expectation and avoidance of injury in comparison to females. This study also contrasted two additional hypotheses, one suggesting an invincibility belief in teenagers, producing a curvilinear age trend, with risky cognitions increasing from second grade, peaking at eighth grade, and then decreasing in adulthood. The other hypothesis suggested that with exposure, risky beliefs increased linearly, due to desensitization to cues of risk. As predicted, female participants did expect more fear and pain, and less exhilaration, and braked sooner after seeing the hazard than male participants. Linear rather than curvilinear age patterns emerged across films, revealing that the youngest participants anticipated more fear and less exhilaration than older participants. These results parallel developmental trends in which females and younger participants who anticipate more serious consequences are at lower risk for bicycle injury than are males, older children, and adolescents. Limitations of this analogue study and potential questions for both future research and the application of injury prevention techniques are explored.     

A RAPID METHOD FOR EVALUATING THE NECESSITY FOR BOTH A BEHAVIORAL INTERVENTION AND METHYLPHENIDATE

We examined the effects of a behavioral intervention and methylphenidate (MPH) on inappropriate behavior and sleep disturbance displayed by a 6-year-old boy who had been diagnosed with attention deficit hyperactivity disorder. Results showed that the behavioral intervention was effective in reducing inappropriate behaviors to near-zero levels regardless of the presence or absence of MPH.     

Vision following extended congenital blindness

Animal studies suggest that early visual deprivation can cause permanent functional blindness. However, few human data on this issue exist. Given enough time for recovery, can a person gain visual skills after several years of congenital blindness? In India, we recently had an unusual opportunity to work with an individual whose case history sheds light on this question. S.R.D. was born blind, and remained so until age 12. She then underwent surgery for the removal of dense congenital cataracts. We evaluated her performance on an extensive battery of visual tasks 20 years after surgery. We found that although S.R.D.'s acuity is compromised, she is proficient on mid- and high-level visual tasks. These results suggest that the human brain retains an impressive capacity for visual learning well into late childhood. They have implications for current conceptions of cortical plasticity and provide an argument for treating congenital blindness even in older children.