Despite its avowed goal of understanding individual behavior, the field of behavior analysis has largely ignored the determinants of consistent differences in level of performance among individuals. The present article discusses major findings in the study of individual differences in intelligence from the conceptual framework of a functional…

Increased variability in reaction time (RT) has been proposed as a cardinal feature of attention deficit hyperactivity disorder (ADHD). Increased variability during sustained attention tasks may reflect inefficient fronto-striatal and fronto-parietal circuitry; activity within these circuits is modulated by the catecholamines. A disruption to…

Relatively little is known about the functional development of verbal and nonverbal working memory during adolescence. Behavioral studies have demonstrated that WM capacity increases with age, yet relatively few studies have assessed the relationship between brain-activity and age-related changes in WM capacity, especially as it differs across…

A high prevalence of deficits in explicit learning has been reported for schizophrenic patients, but it is less clear whether these patients are impaired in implicit learning. Deficits in implicit learning indicative of a fronto-striatal dysfunction have been reported using a serial reaction-time task (SRT), but the impact of typical neuroleptic…

A central question in online human sentence comprehension is, "How are linguistic relations established between different parts of a sentence?" Previous work has shown that this dependency resolution process can be computationally expensive, but the underlying reasons for this are still unclear. This article argues that dependency…

The ability to report the temporal order of 2 tactile stimuli (1 applied to each hand) has been shown to decline when the arms are crossed over compared with when they are uncrossed. However, these effects have only been measured when temporal order was reported by stimulus location. It is unknown whether this spatial manipulation of the body…

This study demonstrated effects of age, education, and sex on complex reaction time in a large national sample (N = 3,616) with a wide range in age (32-85) and education. Participants completed speeded auditory tasks (from the MIDUS [Midlife in the U.S.] Stop and Go Switch Task) by telephone. Complexity ranged from a simple repeated task to an…

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)