Tense and syntactic processes in agrammatic speech

This study focuses on inflectional errors in a group of eight, English-speaking people with agrammatism. Subjects were required to provide inflected verbs in declarative sentences and construct negative sentences. The errors made by these speakers are considered in terms of whether they resemble the errors made by children at the Optional Infinitive Stage. Results confirm that the errors differ from those made by children and that a different explanation is required. Explanations offered by Borer and Rohrbacher (1997) and by Friedmann and Grodzinsky (2000) are discussed but are considered inadequate to deal with our data. It is proposed that agrammatic speakers have problems with the implementation of grammar and particularly with syntactic processes such as feature-checking.     

Age and skilled performance: contributions of working memory and processing speed

In this study, we examined the interrelationships among age, working memory (WM), processing speed, and the development of skilled performance. Younger (M=20.5) and older (M=68.9) adults were trained on an alphabet arithmetic task (Haider & Frensch, 1996) administered across three consecutive days. Although older adults were slower than younger adults, both age groups' response latencies decreased as a result of practice. Contrary to expectations, WM and processing speed were significantly correlated with performance late in training. Partial correlations suggested that age differences in performance at the end of training were mediated by individual differences in cognitive processing speed.     

The reliability and validity of the psychopathy checklist: youth version (PCL:YV) in nonincarcerated adolescent males

Current knowledge about the validity of the psychopathy syndrome in youth is limited largely to studies relying on parent-teacher rating scales or slight modifications of adult measures. Recently, the Psychopathy Checklist: Youth Version (PCL:YV) was designed for use with adolescents. However, most studies that have used this measure examined incarcerated males and addressed only validity criteria related to antisocial behavior. We investigated the generality and construct validity of the psychopathy syndrome in an adolescent sample by assessing 115 adolescent males on probation with the PCL:YV. Reliability of measurement was high. PCL:YV ratings predicted not only antisocial behaviour but also other indices of childhood psychopathology, interpersonal behaviors associated with adult psychopathy, and a lack of attachment to parents. These findings suggest that the PCL:YV identifies a syndrome in adolescence consistent with theory and research on adult males.     

Concordance of self- and informant ratings of adults' current and childhood attention-deficit/hyperactivity disorder symptoms

Self-informant rating concordance for attention-deficit/hyperactivity disorder (ADHD) symptoms was assessed in 281 adults at the subscale (Inattention, Hyperactivity-Impulsivity) and individual symptom levels. Potential demographic, diagnostic, and informant identity moderators were also investigated. Concordance levels were similar for current and childhood symptoms. Although moderate positive correlations were found between self- and informant ratings on both subscales, informants endorsed more significant inattentive symptom severity. Kappa coefficients were variable, suggesting low concordance for certain symptoms. Sex and ADHD diagnosis moderated concordance, although effect sizes were small. These results have implications for the use of behavior rating scales in diagnosing ADHD, raise questions about the validity of self- and informant ratings, and support the need to investigate individual-differences variables that may impact concordance.     

A field examination of two measures of work motivation as predictors of leaders' influence tactics

The authors tested 2 motivation measures, the Motivation Sources Inventory (MSI; J. E. Barbuto & R. W. Scholl, 1998) and the Job Choice Decision-Making Exercise (A. M. Harrell & M. J. Stahl, 1981) as predictors of leaders' influence tactics. The authors sampled 219 leader-member dyads from a variety of organizations and communities throughout the central United States. Results strongly favored the MSI as a predictor of influence tactics. Limitations of the study include low power of relationships, sample size as limited by the research design, and education levels of participants. Future researchers should use larger and more diverse samples and test other relevant antecedents of leaders' behaviors.     

Stimulus modality and verbal learning performance in normal aging

The present study investigated the effects of modality presentation on the verbal learning performance of 26 older adults and 26 younger cohorts. A multitrial free-recall paradigm was implemented incorporating three modalities: Auditory, Visual, and simultaneous Auditory plus Visual. Older subjects learned fewer words than younger subjects but their rate of learning was similar to that of the younger group. The visual presentation of objects (with or without the simultaneous auditory presentation of names) resulted in better learning, recall, and retrieval of information than the auditory presentation alone.     

Addressees' needs influence speakers' early syntactic choices

A current debate in psycholinguistics concerns how speakers take addressees' knowledge or needs into account during the packaging of utterances. In retelling stories, speakers are more likely to mention atypical instruments than easily inferrable, typical instruments; in a seminal study, Brown and Dell (1987) suggested that this is not an adjustment to addressees but is simply easiest for speakers. They concluded that manipulating addressees' knowledge did not affect speakers' mention of instruments. However, their addressees were confederates who heard the same stories repeatedly. We had speakers retell stories to naive addressees who either saw or did not see a picture illustrating the main action and instrument. When addressees lacked pictures, speakers were more likely to mention atypical instruments, to mention them early (within the same clause as the action verb), and to mark atypical instruments as indefinite. This suggests that with visual copresence, speakers can take addressees' knowledge into account in early syntactic choices.     

Varieties of preschool hyperactivity: multiple pathways from risk to disorder

In this paper we examine the characteristics of preschool attention deficit hyperactivity disorder (ADHD) from both mental disorder and developmental psychopathology points of view. The equivalence of preschool and school-aged hyperactivity as a behavioral dimension is highlighted together with the potential value of extending the use of the ADHD diagnostic category to the preschool period where these behaviours take an extreme and impairing form (assuming age appropriate diagnostic items and thresholds can be developed). At the same time, the importance of identifying pathways between risk and later ADHD is emphasized. Developmental discontinuity and heterogeneity are identified as major characteristics of these pathways. We argue that models that distinguish among different developmental types of early-emerging problems are needed. An illustrative taxonomy of four developmental pathways implicating preschool hyperactivity is presented to provide a framework for future research.     

Reconsolidation after remembering an odor-reward association requires NMDA receptors

A rapidly learned odor discrimination task based on spontaneous foraging behavior of the rat was used to evaluate the role of N-methyl-D-aspartate (NMDA) receptors (NMDARs) in ongoing memory consolidation. Rats were trained in a single session to discriminate among three odors, one of which was associated with palatable food reward. Previous experiments showed that the NMDAR antagonist DL-APV induced amnesia for this task when injected immediately after training. In the present study, memory was reactivated 24 h after training by exposure to the rewarded odor within the experimental context after which rats received an intracerebroventricular injection of APV. Combined reactivation-drug treatment induced profound amnesia when tested 48 h later. Animals receiving drug alone, in absence of reactivation, showed perfect retention. It is concluded that NMDARs support a consolidation process taking place after memory reactivation.