Attending to a misoriented word causes the eyeball to rotate in the head

Torsional eye movements are triggered by head tilt and a rotating visual field. We examined whether attention to a misoriented form could also induce torsion. Thirty-six observers viewed an adapting field containing a bright vertical Une, and then they viewed a display that was composed of two misoriented words (one rotated clockwise, the other counterclockwise, by 15°, 30°, or 45°). The subjects were instructed to attend to one of the words. The subjects’ adjustments of a reference line to match the tilt of the afterimage showed that attention to a misoriented word produces torsional eye movement (verified with direct measurements on 4 additional subjects). This eye movement reduces the retinal misorientation of the word by about 1°. The results of this study reinforce the linkage between selective attention and eye movements and may provide a useful tool for dissecting different forms of “mental rotation” and other adjustments in internal reference frames. Apparent-motion displays confirming that the eye rotated in the head may be downloaded from www.psychonomic.org/archive.     

From fear to love: individual differences in implicit spider associations

The Implicit Association Test (IAT) was used to investigate automatic fear associations in fear of spiders. Fear associations toward spiders were measured among spider fearful and nonfearful participants (Experiment 1) as well as among nonfearfuls and spider enthusiasts (Experiment 2). It was shown that the IAT is sensitive to personal automatic fear associations and therefore distinguishes between high-fearful, nonfearful, and enthusiastic participants. Moreover, implicit spider associations measured by the IAT predicted avoidance behavior beyond self-reports. The results of Experiment 2 provide additional support for the argument that implicit spider associations are different from general stereotypes or knowledge about spiders.     

Effectiveness of dialectical behaviour therapy for borderline personality disorder in an inpatient setting

This study evaluates the effectiveness of dialectical behaviour therapy (DBT) for borderline personality disorder (BPD) in an unselected, comorbid population seeking 3-month inpatient treatment. We studied 50 consecutively admitted individuals (44 women, six men) with BPD as defined by DSM-IV at three time points (at admission, at discharge, and at the 15-month follow-up). For the clinical diagnoses, we used the Structured Clinical Interview for DSM-IV (SCID) and compared the frequencies of comorbid axis I and axis II disorders at admission and at the 15-month follow-up. Overall, participants showed a high degree of comorbidity. Psychopathology was significantly reduced at post-treatment and at follow-up. Effect sizes for outcome measures were within the range of those of previous studies. Our findings support the notion that the results of the DBT efficacy research can be generalized to an inpatient setting and to patients with BPD disorder with high comorbidity.     

Agreement and movement: a syntactic analysis of attraction

This paper links experimental psycholinguistics and theoretical syntax in the study of subject-verb agreement. Three experiments of elicited spoken production making use of specific characteristics of Italian and French are presented. They manipulate and examine its impact on the occurrence of 'attraction' errors (i.e. incorrect agreement with a word that is not the subject of the sentence). Experiment 1 (in Italian) shows that subject modifiers do not trigger attraction errors in free inverted VS (Verb Subject) structures, although attraction was found in VS interrogatives in English (Vigliocco, G., & Nicol, J. (1998). Separating hierarchical relations and word order in language production. Is proximity concord syntactic or linear? Cognition, 13-29) In Experiment 2 (in French), we report stronger attraction with preverbal clitic object pronouns than with subject modifiers. Experiment 3 (in French) shows that displaced direct objects in the cleft construction trigger attraction effects, in spite of the fact that the object does not intervene between the subject and the verb in the surface word order (OSV). Moreover, attraction is stronger in structures with subject-verb inversion (...). These observations are shown to be naturally interpretable through the tools of formal syntax, as elaborated within the Principles and Parameters/Minimalist tradition. Three important constructs are discussed: (1) the hierarchical representation of the sentence during syntactic construction, and the role of intermediate positions by which words transit when they move; (2) the role of specific hierarchical (c-command) but also linear (precedence) relations; and (3) the possibility that agreement involves two functionally distinct components. A gradient of computational complexity in agreement is presented which relates empirical evidence to these theoretical constructs.     

Early changes in muscle activation patterns of toddlers during walking

Early locomotor behavior has been the focus of considerable attention by developmentalists over several decades. Few studies have addressed explicitly patterns of muscle activity that underlie this coordination pattern. Our purposes were to illustrate a method to determine objectively the onset and offset of muscle firings during early walking and to investigate the emergence of patterns of activation of the core locomotor muscles. We tested eight toddlers as they walked overground at walking onset (max. of 3-6 independent steps) and after three months of walking experience. Surface electrodes monitored activity of the gastrocnemius, tibialis anterior, quadriceps, and hamstrings. We reduced EMG signals to a frame-by-frame designation of "on-off," followed by muscle state and co-contraction analyses, and probability distributions for each muscle's activity across multiple cycles. Our results clearly show that at walking onset muscle activity was highly variable with few, if any, muscles showing recurring patterns of behavior, within or among toddlers. Variability and co-activation decreased with walking experience but remained inconsistent, in contrast to the significant increase in stability shown for joint coordination and endpoint (foot placement) parameters. We propose this trend emerges because of the high number of options (muscle combinations) available. Toddlers learn first to marshal sufficient force to balance and make forward progress but slowly discover how to optimize these resources.     

On how to be unpredictable: evidence from the voluntary task-switching paradigm

The voluntary task-switching paradigm requires subjects to select randomly between tasks and promises to provide a window into executive task selection independent of exogenous influences present in standard task-switching situations. We show here that the degree to which subjects perseverate on tasks across trials captures unique individual differences variance, but also that the switch rate is under strong stimulus-driven control: "Voluntary" switches are much more frequent when the stimulus changes than when it repeats. Most important, we show that individuals whose no-switch trials are selectively slowed exhibit less perseveration and stimulus-driven effects (and thus more voluntary selection) than individuals whose no-switch trials do not show this slowing. We suggest that selective slowing indicates a strategy of treating trials as discrete events--possibly through inhibition of the preceding task set. These results not only demonstrate massive nonvoluntary influences on voluntary selection that are largely untapped by standard task-switching measures, but also show how such influences can be counteracted through strategic adaptations.     

Attention and eye movements in reading: inhibition of return predicts the size of regressive saccades

A spatial cuing task was used to identify two types of readers, those with a relatively fast and those with a relatively slow buildup of inhibition of return (IOR). Backward-directed eye movements (regressions) during sentence reading were then examined as a function of the two IOR types. The results revealed that readers with fast IOR executed larger regressions than readers with slow IOR, as they directed the eyes away from the most recently attended area of text. Forward-directed eye movements (saccades), by contrast, were not a function of IOR type. Ease of sentence comprehension influenced the size of regressions, but this effect was also independent of IOR type. Multiple mechanisms of spatial attention, including IOR, bias eye movements toward upcoming words in the text during reading.     

Changes in step variability of new walkers with typical development and with Down syndrome

Models of human gait are based on adult locomotion. C. E. Bauby and A. D. Kuo (2000) proposed that adults rely on passive mechanisms at the spinal level to control motion in the anteroposterior direction and rely on direct monitoring of postural control in the lateral direction. The authors' purpose in this study was to determine if that model applies to control at the onset of walking in typically developing toddlers (n = 9) and in toddlers with Down syndrome (n = 6). Their longitudinal data suggested that toddlers control gait in a distinctly different manner than adults do. An adult pattern of control emerges with experience. In addition, the effect of experience on the emergence of that pattern is magnified by task-specific early intervention. The present data support the emergence and discovery of efficient patterns of control in this fundamental human behavior.     

Semantic inhibition of return is the exception rather than the rule

Inhibition of return (IOR) has recently been reported for lexical/semantic categories (see, e.g., Fuentes, Vivas, & Humphreys, 1999). The present research examines the impact on semantic IOR of three components: item repetition, item heterogeneity, and spatial variability. Experiments 1 and 2 indicate that lexical/semantic IOR occurs only after extensive repetition. Experiment 2 also shows that semantic IOR is independent of spatial variability. Experiments 3 through 5 show facilitatory rather than inhibitory effects when the item pool is heterogeneous. The results support an episodic account of semantic IOR, according to which inhibitory effects accumulate with massive repetition of homogeneous items.