Ordinal position learning and remote anticipation

Rats were runway trained on each of two 3-trial series of reward outcomes. The series are labeled XNY and ZNN, for which X represents a trial that was rewarded with Noyes pellets and N represents a trial that ended with no reward. Units of distinctively flavored breakfast cereals served as reward on trials labeled Y and Z. One group (Floor) had each series occur with a correlated runway floor, either smooth and black or rough and white. For a second group (Memory), the floor cue was uncorrelated with series. Animals in both groups learned to approach the goal rapidly on the 1st trials of the 2 series and slowly on the 2nd trials, but only Group Floor learned to differentiate the 3rd trials of the series. These results recommend a view of serial learning that emphasizes the role played by information about the ordinal position of series items.     

Developmental changes in children's abilities to share and allocate attention in a dual task

Characterizing developmental changes in children's dual-task performance has been problematic because differences in divided attention abilities are easily confounded with differences in overall capacity. Two experiments showed that after individual differences in children's capacity for single-task performance were controlled for, age differences between second- (M = 8.1 years) and fifth-grade (M = 11.1 years) children did not exist in dual-task performance when tasks were of equal priority. However, when tasks had different priorities, only fifth-grade children could differentially allocate attention in the dual task. Results are discussed within the coordination hypothesis framework (see A. F. Kramer & J. L. Larish, 1996), which suggests that changes in dual-task performance with aging are due to changes in the ability to coordinate and control the allocation of attention. It is argued that linking the investigations of children's attention with research on attention and aging provides both methodological and theoretical benefits.     

Tall is typical: Central tendency, ideal dimensions, and graded category structure among tree experts and novices

Many accounts of categorization equate goodness-of-example with central tendency for common taxonomic categories; the best examples of a category are average members--those that are most similar to most other category members. In the present study, we asked 24 tree experts and 20 novices to rate goodness-of-example for a sample of 48 trees and found (1) that the internal structure of the category tree differed between novices and experts and (2) that central tendency did not determine goodness-of-example ratings for either group. For novices, familiarity determined goodness-of-example ratings. For experts, the "ideal" dimensions of height and weediness, rather than average similarity to other trees, were the primary predictors of goodness-of-example ratings for experts. The best examples of tree were not species of average height, but of extreme height. The worst examples were the weediest trees. We also found systematic differences in predictors of goodness-of-example as a function of type of expertise. We argue that the internal structure of taxonomic categories can be shaped by goal-related experience and is not necessarily a reflection of the attributional structure of the environment. Implications for models of category structure and category learning are discussed.     

Factor structure of the Eyberg Child Behavior Inventory: a parent rating scale of Oppositional Defiant Behavior Toward Adults, Inattentive Behavior, and Conduct Problem Behavior

Used the Eyberg Child Behavior Inventory (ECBI) to measure disruptive behavior problems in children and adolescents. A controversy exists, however, on the dimensional structure of the ECBI. To evaluate this issue, an exploratory factor analysis was first performed on a sample of 1,263 children and adolescents. This analysis identified 3 meaningful factors (i.e., Oppositional Defiant Behavior Toward Adults, Inattentive Behavior and Conduct Problem Behavior) and a fourth, poorly defined factor. A confirmatory factor analysis (CFA) evaluated the fit of the 3 meaningful factors in a second sample of 1,264 children and adolescents. The 3-factor model with 2 correlated errors provided a excellent fit. This 3-factor model also provided a significantly better fit than 2- and 1-factor models. Multiple group CFA indicated that the factor pattern, item-factor loadings, factor correlations, and correlated errors were equivalent across the samples. The CFA on sex yielded similar results. Initial normative information is presented for boys (n = 1,322) and girls (n = 1,205) within 4 age ranges (i.e., 2-5, 6-9, 10-13, 14-17) for the 3 factors. The use of these 3 factors, especially Oppositional Defiant Behavior and Conduct Problem Behavior, should make the ECBI more useful as a screening and outcome measure.     

Behavioral versus Behavioral and Pharmacological Treatment in ADHD Children Attending a Summer Treatment Program

As part of the behavioral treatment in the Multimodal Treatment Study of Children with ADHD (MTA), children participated in an intensive summer treatment program (STP). This study examined the differences between 57 children in the combined treatment (Comb) group, who were medicated, and 60 children in the behavioral treatment (Beh) group, who were unmedicated throughout the STP. Comb children were significantly better than Beh on 5 measures: rule following, good sportsmanship, peer negative nominations, and STP teacher posttreatment ratings of inattention/overactivity. Groups did not differ on any of the other 30 measures, and responded similarly to the STP over time. Comparisons to normative data revealed that Comb children were more likely to fall within the normative range on 6 measures. The differences between these results and the main MTA results, in which Comb was always superior to Beh, are discussed in terms of the relative intensity of combined treatments. The implications for future studies of pharmacological and behavioral treatment for ADHD are discussed.     

The category access measure of relational processing

Increases in category access (CA) and items recalled per category (IPC) are associated with increases in relational and item-specific processing, respectively. However, it has also been shown that CA increases as recall level increases and that CA scores following relational processing are actually below CA scores for randomly recalled items. These results prompted M. D. Murphy (1979) to suggest that, after adjusting for recall-level differences, relational processing decreases CA scores. Results of Experiment 1, along with a reanalysis of previously published data, showed that relational processing produces lower CA scores than purely item-specific processing (or random recall), but an increase in relational processing produces an increase in CA scores even when the CA and IPC scores are adjusted for recall-level differences. These results suggest a curvilinear relationship between relational processing and CA scores.     

Problem of item overlap between the psychopathy screening device and attention deficit hyperactivity disorder, oppositional defiant disorder, and conduct disorder rating scales

Content validity requires a clear definition of the construct of interest and the delineation of the construct from similar constructs. Content validity also requires that the items be representative of the construct as well as specific to the construct. An examination of the items on the Psychopathy Screening Device (PSD), a parent- and teacher-rating scale of childhood psychopathy, indicates significant overlap with the symptoms and associated features of attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD). The failure of the PSD to have unique items results in poor discriminant validity with ADHD, ODD, and CD rating scales. More careful attention to content validation guidelines is required to develop a more useful measure of childhood psychopathy.     

Retrieval-induced forgetting: Evidence for a recall-specific mechanism

Previous work has shown that recalling information from long-term memory can impair the long-term retention of related representations—a phenomenon known as retrieval-induced forgetting (Anderson, Bjork, & Bjork, 1994). We report an experiment in which the question of whether retrieval is necessary to induce this form of impairment was examined. All the subjects studied six members from each of eight taxonomic categories (e.g.,fruit orange). In the competitive practice condition, the subjects practiced recalling three of the six members, using category-stem cues (e.g.,fruit or____). In the noncompetitive practice condition, the subjects were reexposed to these same members for the same number of repetitions but were asked to recall the category name by using the exemplar and a stem as cues (e.g.,fr____orange). Despite significant and comparable facilitation of practiced items in both conditions, only the competitive practice subjects were impaired in their ability to recall the nonpracticed members on a delayed cued-recall test. These findings argue that retrieval-induced forgetting is not caused by increased competition arising from the strengthening of practiced items, but by inhibitory processes specific to the situation of recall.