Prioritization of new objects in real-world scenes: evidence from eye movements

The authors examined the prioritization of abruptly appearing objects in real-world scenes by measuring the eyes' propensity to be directed to the new object. New objects were fixated more often than chance whether they appeared during fixations (transient onsets) or saccades (nontransient onsets). However, onsets that appeared during fixations were fixated sooner and more often than those coincident with saccades. Prioritization of onsets during saccades, but not fixations, were affected by manipulations of memory: Reducing scene viewing time prior to the onset eliminated prioritization, whereas prior study of the scenes increased prioritization. Transient objects draw attention quickly and do not depend on memory, but without a transient signal, new objects are prioritized over several saccades as memory is used to explicitly identify the change. These effects were not modulated by observers' expectations concerning the appearance of new objects, suggesting the prioritization of a transient is automatic and that memory-guided prioritization is implicit.     

Preview search and contextual cuing

We investigated the effect of contextual cuing (M. M. Chun & Y. Jiang, 1998) within the preview paradigm (D. G. Watson & G. W. Humphreys, 1997). Contextual cuing was shown with a 10-item letter search but not with more crowded 20-item displays. However, contextual learning did occur in a preview procedure in which 10 preview items were followed by 10 new items. Repeating the new items alone did not generate contextual learning, but repeating the preview items alone did, as long as they had a consistent spatial relation with the target. This was not merely due to the onset of the preview items being associated with the target location. No learning effect took place with a preview of homogeneous items that competed less for selection with new stimuli. The results provide evidence for old items being processed in preview search and providing a context for subsequent search of new items.     

Hierarchical organisation of neuro-anatomical constraints in interlimb coordination

Based on the observation that bimanual finger tapping movements tend toward mirror symmetry with respect to the body midline, despite the synchronous activation of non-homologous muscles, F. Mechsner, D. Kerzel, G. Knoblich, and W. Prinz (2001) [Perceptual basis of bimanual coordination. Nature, 414, 69-73] suggested that the basis of rhythmic coordination is purely spatial/perceptual in nature, and independent of the neuro-anatomical constraints of the motor system. To investigate this issue further, we employed a four finger tapping task similar to that used by F. Mechsner and G. Knoblich (2004) [Do muscle matter in bimanual coordination? Journal of Experimental Psychology: Human Perception and Performance, 30, 490-503] in which six male participants were required to alternately tap combinations of adjacent pairs of index (I), middle (M) and ring (R) fingers of each hand in time with an auditory metronome. The metronome pace increased continuously from 1 Hz to 3 Hz over the course of a 30-s trial. Each participant performed three blocks of trials in which finger combination for each hand (IM or MR) and mode of coordination (mirror or parallel) were presented in random order. Within each block, the right hand was placed in one of three orientations; prone, neutral and supine. The order of blocks was counterbalanced across the six participants. The left hand maintained a prone position throughout the experiment. On the basis of discrete relative phase analyses between synchronised taps, the time at which the initial mode of coordination was lost was determined for each trial. When the right hand was prone, transitions occurred only from parallel symmetry to mirror symmetry, regardless of finger combination. In contrast, when the right hand was supine, transitions occurred only from mirror symmetry to parallel but no transitions were observed in the opposite direction. In the right hand neutral condition, mirror and parallel symmetry are insufficient to describe the modes of coordination since the hands are oriented orthogonally. When defined anatomically, however, the results in each of the three right hand orientations are consistent. That is, synchronisation of finger tapping is determined by a hierarchy of control of individual fingers based on their intrinsic neuro-mechanical properties rather than on the basis of their spatial orientation.     

Bi-phasic hitting with constraints on impact velocity and temporal precision

The aim of the experiment was to investigate how bi-phasic hitting movements are organized to comply with both impact and temporal precision constraints. 'Bi-phasic' refers to a sequential movement with a preparatory movement away from the interception location followed by a strike phase. The interception location was fixed, as the motion of the hitting device was constrained to follow a straight path orthogonal to that of the approaching balls. We manipulated the required temporal precision by projecting balls with different constant approach speeds (1, 1.5, and 2m/s). Different impact constraints were imposed by instructing participants first to simply hit the ball and subsequently to hit the ball to a designated target area located either 55 or 105 cm away from the interception location. We determined several kinematic variables and used Principal Component Factor Analysis to classify these variables. The analysis revealed two independent factors: a 'velocity' factor (formed by impact velocity, peak velocity of the preparatory phase, peak velocity of the strike phase, and amplitude of the strike) and a 'timing' factor (formed by onset of the preparatory phase, moment of peak velocity of the preparatory phase, and onset of the strike phase). The 'velocity' factor scaled significantly with the required impact constraint and the 'timing' factor scaled significantly with ball speed.     

Development of upper limb proprioceptive accuracy in children and adolescents

This study was designed to determine differences in the proprioceptively guided movements of children (8-10 years) and adolescents (16-18 years). Participants were blindfolded and asked to actively match passively determined target positions of the elbow joint under three matching conditions. Overall, children were less accurate than adolescents in all matching tasks and utilized different kinematic strategies for making the matching movements. Specifically, children made larger absolute errors and utilized matching movements which, compared to adolescents, were of shorter duration and less irregular in terms of their velocity profiles. An assessment of limb asymmetry was also performed revealing a non-dominant arm matching advantage but only for children and only in the task requiring interhemispheric transfer of a memory-based model of limb position. The proprioceptive differences observed in this study are likely the result of experience-driven refinement in the utilization of somatosensory feedback throughout childhood and into adolescence.     

Studies of Work: Achieving Hybrid Disciplines in IT Design and Management Studies

We explore the relationship between ethnomethodology (EM), ethnography and the needs of managers and designers in industry, considering both ethnomethodological and industrial criteria of adequacy and explicating their relationship through the concept of “audience.” We examine a range of studies in this light, with a view to their possible candidacy as hybrid studies and identify three types of application of EM studies of work: market research, design, and business improvement. Application in the first of these fields we dub “anthropological,” in that it consists in studying and reporting back on the ways of exotic people (customers). This is the application most commonly found in studies of computer supported co-operative work (CSCW). A second CSCW application, “technomethodology,” involves the introduction of EM concepts into the design process. A further application, dubbed “holding-up-a-mirror,” involves reporting back to members of a setting upon their own activities. We argue that technomethodology and holding-up-a-mirror both offer the possibility of creating hybrid disciplines. We consider the objection that improvement and design involve the introduction of value judgements that threaten the practice of EM indifference, arguing that action research can serve as a guarantee of unique adequacy (UA) by testing the researcher’s understanding as analysis in action in the setting. Furthermore, the standard of reporting required by the UA criterion contributes to the effectiveness of proposed solutions.     

Does retrieval fluency contribute to the underconfidence-with-practice effect?

Judgments of learning (JOLs) made during multiple study-test trials underestimate increases in recall performance across those trials, an effect that has been dubbed the underconfidence-with-practice (UWP) effect. In 3 experiments, the authors examined the contribution of retrieval fluency to the UWP effect for immediate and delayed JOLs. The UWP effect was demonstrated with reliable underconfidence on Trial 2 occurring for both kinds of JOL. However, in contrast to a retrieval-fluency hypothesis, fine-grained analyses indicated that the reliance of JOLs on retrieval fluency contributed minimally to the UWP effect. Our discussion focuses on the status of the retrieval-fluency hypothesis for the UWP effect.     

Eye gaze and individual differences consistent with learned attention in associative blocking and highlighting

The associative learning effects called blocking and highlighting have previously been explained by covert learned attention, but evidence for learned attention has been indirect, via models of response choice. The present research reports results from eye tracking consistent with the attentional hypothesis: Gaze duration is diminished for blocked cues and augmented for highlighted cues. If degree of attentional learning varies across individuals but is relatively stable within individuals, then the magnitude of blocking and highlighting should covary across individuals. This predicted correlation is obtained for both choice and eye gaze. A connectionist model that implements attentional learning is shown to fit the data and account for individual differences by variation in its attentional parameters.     

Cross-Cultural Reactions to Academic Sexual Harassment: Effects of Individualist vs. Collectivist Culture and Gender of Participants

Male and female university students from the United States, Canada, Germany, the Netherlands, Ecuador, Pakistan, the Philippines, Taiwan, and Turkey read a standardized scenario in which a male professor was accused of sexually harassing a female graduate student. Respondents from individualist countries judged the professor to be guilty of sexual harassment more often than did those from collectivist countries. Women rendered significantly more guilty judgments and assigned more severe punishments to the accused professor than did men. Implications for the individualist–collectivist classification system and cross-cultural research are discussed.     

Beyond heritability: neurotransmitter genes differentially modulate visuospatial attention and working memory

A cued, visuospatial attention task and a working memory task were administered to 89 healthy adults genotyped for a T-to-C polymorphism in CHRNA4, a nicotinic receptor subunit gene. Increasing gene dose of the C allele of the CHRNA4 gene (i.e., no C alleles, one C allele, two C alleles) was associated with increased reaction time (RT) benefits of valid attentional cuing and reduced RT costs of invalid cues, but was not associated with working memory performance. In a second experiment, 103 healthy persons were genotyped for a G-to-A polymorphism of the dopamine beta-hydroxylase (DBH) gene. Increasing gene dose of the G allele of the DBH gene was associated with increased working memory accuracy at a high memory load. However, there was no consistent association between the DBH gene and visuospatial attention. Thus, a double dissociation was observed, with visuospatial attention associated with CHRNA4 but not the DBH gene and, conversely, working memory associated with the DBH gene but not CHRNA4. The results show that normal allelic variations in single neurotransmitter genes modulate individual differences in processing components of cognitive functions in healthy individuals.