Tangible pictures: viewpoint effects and linear perspective in visually impaired people

Perception of raised-line pictures in blindfolded-sighted, congenitally blind, late-blind, and low-vision subjects was studied in a series of experiments. The major aim of the study was to examine the value of perspective drawings for haptic pictures and visually impaired individuals. In experiment 1, subjects felt two wooden boards joined at 45 degrees, 90 degrees, or 135 degrees, and were instructed to pick the correct perspective drawing from among four choices. The first experiment on perspective found a significant effect of visual status, with much higher performance by the low-vision subjects. Mean performance for the congenitally blind subjects was not significantly different from that of the late-blind and blindfolded-sighted subjects. In a further experiment, blindfolded subjects drew tangible pictures of three-dimensional (3-D) geometric solids, and then engaged in a matching task. Counter to expectations, performance was not impaired for the 3-D drawings as compared with the frontal viewpoints. Subjects were also especially fast and more accurate when matching top views. Experiment 5 showed that top views were easiest for all of the visually impaired subjects, including those who were congenitally blind. Experiment 5 yielded higher performance for 3-D than frontal viewpoints. The results of all of the experiments were consistent with the idea that visual experience is not necessary for understanding perspective drawings of geometrical objects.     

Relations among children's perceptions of maternal behavior,attributional styles,and behavioral symptomatology in maltreated children

This investigation examined relations among perceptions of mothers, attributional style, and counselor-rated behavior problems in 187 school age children (88 maltreated, 99 nonmaltreated). Hypotheses regarding the presence of higher levels of internalizing and externalizing behavior problems in maltreated children were confirmed. Attributional style was found to function as a moderator of externalizing behavior problems, suggesting that attributional style exerts a protective role against the harmful effect of child maltreatment. Perceptions of mothers were found to operate as a mediator of both internalizing and externalizing symptomatology, with maltreated children with less positive perceptions of their mothers exhibiting greater internalizing and externalizing behavior problems. These findings advance knowledge of how cognitive processes contribute to behavior problems in maltreated children and possess implications for prevention and intervention efforts.     

Medical burden, cerebrovascular disease, and cognitive impairment in geriatric depression: modeling the relationships with the CART analysis

Herein, the background information reflecting roles of medical burden, cerebrovascular disease and risk factors, and cognitive impairment in geriatric depression are reviewed. The authors then propose a nonparametric statistical approach to the data analysis of multiple putative causal variables for late-life depression, the Classification and Regression Tree Analysis. This analysis presents a useful approach to modeling nonlinear relationships and interactions among variables measuring physical and mental health, as well as magnetic resonance imaging and cognitive measures in depressed elderly. This method uncovers the existing interactions among multiple predictor variables, and provide thresholds for each variable, at which its predictive power becomes statistically significant. It presents a "hierarchy" of the predictors in a form of a decision tree by finding the best combination of predictors of an outcome. The authors present two models based on demographic variables, measures of vascular and nonvascular medical burden, neuroimaging indices, the Mini-Mental State Examination score, and neuropsychological test scores of 81 elderly depressed subjects. Cognitive tests of verbal fluency and executive function are identified as the best predictors of depression, followed by the frontal lobe volume and Mini-Mental State Examination. The authors observed that an interaction between frontal lobe volume, total lesion volume, and medical burden was predictive of depression.     

Subcellular interactions between parallel fibre and climbing fibre signals in purkinje cells predict sensitivity of classical conditioning to interstimulus interval

Classical conditioning of the nictitating membrane response requires a specific temporal interval between conditioned stimulus and unconditioned stimulus, and produces an incrase in Protein Kinase C (PKC) activation in Purkinje cells. To evaluate whether biochemical interactions within the Purkinje cell may explain the temporal sensitivity, a model of PKC activation byCa ²⁺, diacylglycerol (DAG), and arachidonic acid (AA) is developed.Ca ²⁺ elevation is due to CF stimulation and IP3 inducedCa ²⁺ release (IICR). DAG andIP ₃ result from PF stimulation, while AA results from phospholipase A2 (PLA ₂). Simulations predict increased PKC activation when PF stimulation precedes CF stimulation by 0.1 to 3 s. The sensitivity of IICR to the temporal relation between PF and CF stimulation, together with the buffering system of Purkinje cells, significantly contribute to the temporal sensitivity.     

When fit indices and residuals are incompatible

Standard chi-square-based fit indices for factor analysis and related models have a little known property: They are more sensitive to misfit when unique variances are small than when they are large. Consequently, very small correlation residuals indicating excellent fit can be accompanied by indications of bad fit by the fit indices when unique variances are small. An empirical example of this incompatibility between residuals and fit indices is provided. For illustrative purposes, an artificial example is provided that yields exactly the same correlation residuals as the empirical example but has larger unique variances. For this example, the fit indices indicate excellent fit. A theoretical explanation for this phenomenon is provided using relationships between unique variances and eigenvalues of the fitted correlation matrix.     

Inventory of Interpersonal Problems Personality Disorder scales: operating characteristics and confirmatory factor analysis in nonclinical samples

Research involving clinical samples has demonstrated the utility of a 28-item personality disorder (PD) screening measure (Inventory of Interpersonal Problems--Personality Disorder scale [IIP-PD]) culled from the IIP in the prediction of the presence or absence of a PD (Pilkonis, Kim, Proietti, & Barkham, 1996). This article extends these diagnostic efficiency findings to nonclinical samples and presents additional data regarding the factor structure of the 28 IIP-PD items. Diagnostic efficiency statistics for the IIP-PD scale, calculated using both interview and self-report methods, support the utility of the IIP-PD scale as a screening tool for the presence or absence of a PD. High specificity estimates indicate that individuals who do not exceed Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) symptom thresholds rarely exceed the IIP-PD cutoff. Furthermore, a high negative predictive power (NPP) estimate derived using an interview-based diagnostic standard suggests that the IIP-PD scale accurately screens out individuals who do not have a PD. Finally, cross-validated confirmatory factor-analytic results involving items composing the 5 IIP PD subscales identified in previous research (Kim, Pilkonis, & Barkham, 1997) suggest that a measurement model with a single second-order factor (general PD) and 5 first-order factors (one representing each PD subscale) provided the best fit to the observed data compared to 2 other competing models.     

Patterns of comprehension and production of nouns and verbs in agrammatism: implications for lexical organization

This study examined the relationship between verb retrieval and verb-argument-structure properties in seven agrammatic aphasic patients using tasks requiring access to the verb's lexicon for both comprehension- and productionlike processes. Results showed intact comprehension of both nouns and verbs and noun naming, but impaired naming of verbs. Subjects also demonstrated near-normal performance on a grammaticality judgment task involving verb-argument-structure violations but were impaired in categorizing verbs by type (based on number of obligatory arguments). In both naming and categorization conditions, a hierarchy of verb difficulty emerged. Subjects were more accurate in naming/categorizing one-place verbs than two-place verbs and more accurate in naming/categorizing two-place verbs than three-place verbs. The pattern of selective impairment in lexical access/retrieval supports the hypothesis that one dimension of normal lexical organization is by form class. The results also suggest that no necessary relationship exists between production difficulties and comprehension of nouns/verbs in agrammatism. Further, the performance pattern noted supports the claim that verb-argument-structure properties, an important component of the verb lexicon, influence verb production at the single-word and at the sentence level. Subjects' performance on different tasks suggests that the locus of breakdown in the verb-retrieval processes for productionlike tasks may be in accessing information at the lemma level of representation as per Bock's model (1995) of sentence production.     

How the quality of third parties' settlement solutions is affected by the relationship between negotiators

Observers watched videotapes of people negotiating. In half of the videotapes, the negotiators had a negative relationship; in the other half, the negotiators had a positive relationship. Some observers believed that the relationship was a genuine reflection of how the parties felt about one another; others were told that the behavior of negotiators was strategic (i.e., used by parties to gain advantage). Following the tape, observers recommended a settlement. Observers' suggestions were most efficient when the negotiators' relationship was positive and genuine; observers proposed significantly worse solutions when negotiators' relationships were negative and genuine. The authors advise mediators to focus on the issues rather than the emotional tone and to avoid the correspondence bias when observing conflicts among parties with negative relationships.