Time judgments in global temporal contexts

With three experiments, we examined the effects of global temporal context on time judgments as gauged by constant errors (CEs) and estimates of a preferred period (P). In Experiment 1, participants in seven different conditions listened to sequences of a given rate (with interonset intervals ranging from 200 to 800 msec) and judged the relative duration of a final (comparison) time interval. No P emerged. In Experiments 2 and 3, we embedded the same rates in different global (session) contexts that varied according to (1) mean session rate, (2) standard deviation, (3) range, and (4) number of different rates in a session. Evidence from CEs indicated that P varied primarily as a function of mean session rate and range of tempi. The best predictor of errors involved a measure termed relative range (RR = range/mean session rate). A general algorithm incorporating RR successfully predicts P, and the implications of this algorithm are discussed.     

Boundary extension: the role of magnification, object size, context, and binocular information

Boundary extension is a tendency to remember close-up scenes as if they extended beyond the occluding boundaries. The authors explored the contributing factors using brief retention intervals and computer-generated images. Boundary extension turns out to be more complex than previously thought and is not linked to the effects of image magnification and field-of-view changes. Although this is consistent with the idea that boundary extension is the product of the activation of a mental schema that provides information of what is likely to exist outside the picture boundaries, the authors also found that properties of the object at the center of the picture can affect boundary extension independently of the information at the boundaries. In a test of boundary extension using stereograms, the effect does not seem to depend on amount of perceived depth, suggesting a weaker link to perception of space than previously hypothesized.     

Influence of swing leg movement on running stability

The aim of this study was to investigate the role of the swing leg movement on running stability. A simple model was used describing a forward hopping motion. The model consisted of two sub-models, namely a spring-mass system for the stance phase and a functional control model for the swing phase (represented by a passive or actively driven pendulum). To verify the main simulation results, an experimental study on treadmill running was performed. The results of the model indicated that for certain running speeds and pendulum lengths, the behavior of the mechanical system was stable. The following characteristic dependencies between the model parameters were observed. (1) Pendulum length and hip muscle activity determined running height and therefore swing duration. (2) Horizontal velocity was inversely related to leg angle of attack. Increased speed corresponded to flatter leg angles at touch-down, which is in agreement with experimental studies and previous predictions of spring-mass running. It was shown that a biologically motivated control approach with oscillating leg movements is well capable of generating stable hopping movements. Due to its simplicity, however, the monopedal model failed to explain more detailed mechanisms like the swing-leg to stance-leg interaction or the functional role of the leg segmentation. This simple model is therefore considered as a functional mechanical template for legged locomotion, which could help to build more elaborate models in the future.     

Study repetition and the rejection of conjunction lures

Four experiments were conducted to provide further support for a dual-process approach to conjunction errors in recognition memory over a single-process approach. In Experiments 1, 2a, and 2b study words were repeated once (2 presentations) or several times (8 or 16 presentations), and a response signal delay (RSD) was manipulated (short vs long). Short RSD groups produced lower hit rates but higher conjunction error rates compared to long RSD groups. Repetition effects on conjunction errors occurred for short RSD but not long RSD groups. In Experiment 3, additional judgements on new items were solicited to show that the "null" effects for long RSD groups in the earlier experiments were, in fact, illusory. Together, the experiments provide evidence for recollection-based rejections of conjunction lures and support a dual-process theory of recognition memory over a single-process model.     

A dynamic developmental theory of attention-deficit/hyperactivity disorder (ADHD) predominantly hyperactive/impulsive and combined subtypes

Attention-deficit/hyperactivity disorder (ADHD) is currently defined as a cognitive/behavioral developmental disorder where all clinical criteria are behavioral. Inattentiveness, overactivity, and impulsiveness are presently regarded as the main clinical symptoms. The dynamic developmental behavioral theory is based on the hypothesis that altered dopaminergic function plays a pivotal role by failing to modulate nondopaminergic (primarily glutamate and GABA) signal transmission appropriately. A hypofunctioning mesolimbic dopamine branch produces altered reinforcement of behavior and deficient extinction of previously reinforced behavior. This gives rise to delay aversion, development of hyperactivity in novel situations, impulsiveness, deficient sustained attention, increased behavioral variability, and failure to "inhibit" responses ("disinhibition"). A hypofunctioning mesocortical dopamine branch will cause attention response deficiencies (deficient orienting responses, impaired saccadic eye movements, and poorer attention responses toward a target) and poor behavioral planning (poor executive functions). A hypofunctioning nigrostriatal dopamine branch will cause impaired modulation of motor functions and deficient nondeclarative habit learning and memory. These impairments will give rise to apparent developmental delay, clumsiness, neurological "soft signs," and a "failure to inhibit" responses when quick reactions are required. Hypofunctioning dopamine branches represent the main individual predispositions in the present theory. The theory predicts that behavior and symptoms in ADHD result from the interplay between individual predispositions and the surroundings. The exact ADHD symptoms at a particular time in life will vary and be influenced by factors having positive or negative effects on symptom development. Altered or deficient learning and motor functions will produce special needs for optimal parenting and societal styles. Medication will to some degree normalize the underlying dopamine dysfunction and reduce the special needs of these children. The theory describes how individual predispositions interact with these conditions to produce behavioral, emotional, and cognitive effects that can turn into relatively stable behavioral patterns.     

An examination of three sets of MMPI-2 personality disorder scales

Three sets of personality disorder scales (PD scales) can be scored for the MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989). Two sets (Levitt & Gotts, 1995; Morey, Waugh, & Blashfield, 1985) are derived from the MMPI (Hathaway & McKinley, 1983), and a third set (Somwaru & Ben-Porath, 1995) is based on the MMPI-2. There is no validity research for the Levitt and Gotts scale, and limited validity research is available for the Somwaru and Ben-Porath scales. There is a large body of research suggesting that the Morey et al. scales have good to excellent convergent validity when compared to a variety of other measures of personality disorders. Since the Morey et al. scales have established validity, there is a question if additional sets of PD scales are needed. The primary purpose of this research was to determine if the PD scales developed by Levitt and Gotts and those developed by Somwaru and Ben-Porath contribute incrementally to the scales developed by Morey et al. in predicting corresponding scales on the MCMI-II (Millon, 1987). In a sample of 494 individuals evaluated at an Army medical center, a hierarchical regression analysis demonstrated that the Somwaru and Ben-Porath Borderline, Antisocial, and Schizoid PD scales and the Levitt and Gotts Narcissistic and Histrionic scales contributed significantly and meaningfully to the Morey et al. scales in predicting the corresponding MCMI-II (Millon, 1987) scale. However, only the Somwaru and Ben-Porath scales demonstrated acceptable internal consistency and convergent validity.     

Implementation of a comprehensive schoolwide behavioral intervention: The ABC program

The Academic and Behavioral Competencies (ABC) Program, a schoolwide program to reduce classroom disruption and encourage rule following, academic task completion, and homework completion, is described. The program was initially developed and implemented in an elementary school with a high-risk population. Data from teachers, parents, and children indicate high levels of satisfaction with the program. In addition, unobtrusive measures of program impact, reported as reductions in referrals to the principal's office, suspensions, and increases in homework completion rates relative to the year prior to implementation of the program, suggest a preliminary positive impact of the program. A replication is reported for another school district, with teacher evaluations of satisfaction and effectiveness reported, supporting the flexibility and adaptability of the program. Although the present article does not constitute a systematic evaluation of the ABC Program, it presents preliminary data on the process of implementation and stakeholder satisfaction.     

Women's exposure to thin-and-beautiful media images: body image effects of media-ideal internalization and impact-reduction interventions

Exposure to media images of thin-and-beautiful women negatively affects the body image and mood states of young women. However, not all women are equally susceptible to these effects. The present experimental investigation with 123 young college women evaluated the moderating effects of the extent of internalization of media ideals. It also examined the preventative impact of two brief interventions (i.e., media literacy information with and without a dissonance-induction procedure). Results indicated that relative to a control group, the exposure to thin-and-beautiful media images adversely influenced the state body image of participants with high internalization levels. Media-literacy psychoeducation prior to the media exposure prevented this adverse effect. Adding a pre-exposure dissonance-induction procedure did not significantly enhance the preventative effects relative to psychoeducation alone. These results and their implications for the treatment and prevention of body image disturbances are discussed in the context of the empirical literature on the media's effects on body image.     

When does word meaning affect immediate serial recall in semantic dementia?

Patients with semantic dementia can show superior immediate recall of words that they still understand relatively well, as compared with more semantically degraded words, suggesting that conceptual knowledge makes a major contribution to phonological short-term memory. However, a number of studies have failed to show such a recall difference, challenging this view. We examined the effect of several methodological factors on the recall of known and degraded words in 4 patients with semantic dementia, in order to investigate possible reasons for this discrepancy. In general, our patients did exhibit poorer recall of the degraded words and made more phonological errors on these items. In addition, set size affected the magnitude of the recall advantage for known words. This finding suggests that semantic degradation influenced the rate of learning in the immediate recall task when the same items were presented repeatedly. The methods used to select known and degraded items also impacted on the recall difference. List length, however, did not affect the advantage for known words. The coherence of items in phonological short-term memory was affected by their semantic status, but not by the length of the material to be retained. The implications of these findings for the role of semantic and phonological representations in verbal short-term memory are discussed.