The author considers a latent trait model for the response time on a (set of) pure speed test(s), the multiplicative gamma model (MGM), which is based on the assumption that the test response times are approximately gamma distributed, with known index parameters and scale parameters depending on subject ability and test difficulty parameters. Like…

Ideomotor (IM) theory suggests that observing someone else perform an action activates an internal motor representation of that behaviour within the observer. Evidence supporting the case for an ideomotor theory of imitation has come from studies that show imitative responses to be faster than the same behavioural measures performed in response to…

Objective: The present article tests the hypothesis of a sustained attention deficit in children and adults suffering from ADHD. Method: Vigilance and sustained attention of 52 children with ADHD and 38 adults with ADHD were assessed using a computerized vigilance task. Furthermore, the attentional performance of healthy children (N = 52) and…

Fourteen right-handed stutterers and 14 normal speakers responded to monaurally presented stimuli with their right and left hands. Results suggested a bilateral model of neurolinguistic organization for stutterers in which both hemispheres must participate simultaneously in the decoding process. (Author/DB)

The performance of 10 mildly mentally retarded adults on recognition memory tasks in a fixed-set and varied-set procedure was compared with that of nonretarded control subjects. Results suggest that retarded adults use different processing strategies in the two procedures and that rate of processing increases with increasing mental age. (Author/CL)

This study examined the effects of .5-, 1.0- and 5.0-second interresponse intervals on children's lever-pulling responses following success and failure on a ball tower task. (WY)

Based on PhD thesis submitted to the University of Iowa.

The authors suggest that one approach to the clarification of the nature and extent of cognitive process impairments in the mentally retarded and, specifically, the involvement of structural and control process parameters is via an examination of those processes underlying the speed-accuracy operating characteristics of retarded Ss. (Author/SW)

Effective starting techniques for base running are described. (JD)

A comparison of 12 persons with Parkinson's disease (PD), 12 with Alzheimer's disease (AD), and 12 in a control group on a memory scanning task found some slow scanning speed in PD patients. Despite normal scanning speed, most AD patients required highly structured instructions to complete the task, and many remained unable to do so. (SK)

Notes that variety of reaction time measures have been developed and studied as correlates of intelligence. Describes several of most widely used reaction time tests and reports summaries of their correlations with intelligence. Describes model that attempts to account for relationship between speed-of-processing and intelligence in terms of…

Discusses two forms of separability of item and person parameters in the context of response time models. The first is "separate sufficiency," and the second is "ranking independence." For each form a theorem stating sufficient conditions is proved. The two forms are shown to include several cases of models from psychometric…

Research is reviewed to show that the weakness of the reaction time slope parameter (b) of the Hick function x IQ correlation is mainly attributable to statistical artifacts that suppress the parameter's correlation with any other variables, such as the intercept and IQ. Conditions that reduce this suppression are reviewed. (SLD)