Infant temperament and information processing in a visual categorization task

This study investigates the relation between temperament and information processing in 7-month-old infants. Infant temperament was assessed on multiple dimensions, using mothers' ratings on the Infant Behavior Questionnaire (IBQ). Information processing was measured during a paired-comparison visual categorization task. Infants (N=50) were familiarized with five different pairs of visual stimuli from one category, followed by two test trials, each contrasting a novel familiar-category item with a novel out-of-category item (animals vs. vehicles). Drop-out rate in this task was within a normal range (21%). No differences in temperament were found between completers and non-completers, but high reactivity to novelty and low motor activity were positively correlated with the strength of infants' familiarization response. Group comparisons between infants scoring high and low on these two dimensions of temperament confirmed this general finding: infants high on distress to novelty and low on motor activity showed stronger familiarization responses. Furthermore, infants scoring low on motor activity showed a stronger categorization response than highly active infants. This study provides evidence that performance in a cognitive categorization task and dimensions of infant temperament are systematically related during the second half of the first year of life. Implications for cognitive research with infants of this age-range will be discussed.     

Automatic letter priming in an alphabetic decision task

An alphabetic decision task was used to study effects of form priming on letter recognition at very short prime durations (20 to 80 msec). The task required subjects to decide whether a stimulus was a letter or a nonletter. Experiment 1 showed clear facilitatory effects of primes being either physically or nominally identical to the targets, with a stable advantage for the former. Experiment 2 demonstrated that uppercase letters are classified more rapidly as letters (vs. non-letters) when they are preceded by a briefly exposed, forward- and backward-masked, visually similar uppercase letter than when they are preceded by a visually dissimilar uppercase letter. Finally, Experiment 3 demonstrated that nominally identical and visually similar primes facilitate processing more than do nominally identical, visually dissimilar primes. The alphabetic decision task proved to produce sensitive and stable priming effects at the feature, letter, and response-choice level. The present results on letter-letter priming thus constitute a solid data base against which to evaluate other priming effects, such as word-letter priming. The results are discussed in light of current activation models of letter and word recognition and are compared with data simulated by the interactive activation model (McClelland & Rumelhart, 1981).     

Performing a secondary executive task with affective stimuli interferes with decision making under risk conditions

Previous studies demonstrated that executive functions are crucial for advantageous decision making under risk and that therefore decision making is disrupted when working memory capacity is demanded while working on a decision task. While some studies also showed that emotions can affect decision making under risk, it is unclear how affective processing and executive functions predict decision-making performance in interaction. The current experimental study used a between-subjects design to examine whether affective pictures (positive and negative pictures compared to neutral pictures), included in a parallel executive task (working memory 2-back task), have an impact on decision making under risk as assessed by the Game of Dice Task (GDT). Moreover, the performance GDT plus 2-back task was compared to the performance in the GDT without any additional task (GDT solely). The results show that the performance in the GDT differed between groups (positive, negative, neutral, and GDT solely). The groups with affective pictures, especially those with positive pictures in the 2-back task, showed more disadvantageous decisions in the GDT than the groups with neutral pictures and the group performing the GDT without any additional task. However, executive functions moderated the effect of the affective pictures. Regardless of affective influence, subjects with good executive functions performed advantageously in the GDT. These findings support the assumption that executive functions and emotional processing interact in predicting decision making under risk.     

Hemispheric specialization for word classes with visual presentations and lexical decision task

In the present paper we study the possible RH capabilities for the processing of adjectives and verbs of high frequency and medium imagery using a lexical decision task and a horizontal display. In the analysis of both RTs and mean errors, a RVF advantage is obtained. The interaction VF x Word Class did not reach significance. Therefore, we did not find evidence of differences in the visual-field effect for any syntactic class. These results support a LH superiority for the processing of both adjectives and verbs. For the nonword conditions (pseudoverbs and pseudoadjectives), no visual field differences were observed in either group. Methodological aspects are also discussed.     

The impact of task complexity on information use in multi-attribute decision making

This study presents a process analysis of multi-attribute decision making. The decision problems concerned the selection of the most suitable candidate for a job opening. The problems varied in terms of complexity, i.e. the number of candidates and the number of attributes used to describe these alternatives. Results show that with an increasing number of alternatives, subjects (N = 48) used fewer attributes for the evaluation of alternatives, and made, on average, less references to the alternatives. The type of judgment most often used was absolute dimensional (comparison of an attribute to an absolute standard) and was used more often at the beginning than toward the end of the decision process. Overall, judgments were predominantly positive. The percentage of positive judgments decreased with increasing complexity, and toward the end of the decision process. Significantly more judgments, particularly positive ones, concerned the finally chosen alternative as compared to the rest of the alternatives. Finally, analysis of subjects' usage of decision rules revealed that increasing the number of alternatives resulted in an increasing use of elimination strategies. Implications of these findings for the design of decision aids will be discussed.     

Effects of visual information and task constraints on intersegmental coordination in playground swinging

The authors investigated how and to what extent visual information and associated task constraints are negotiated in the coordinative structure of playground swinging. Participants (N = 20) were invited to pump a swing from rest to a prescribed maximal amplitude under 4 conditions: normal vision, no vision, and 2 visual conditions involving explicit phasing constraints. In the latter conditions, participants were presented with a flow pattern consisting of a periodically expanding and contracting optical structure. They were instructed to phase the swing motion so that the forward turning point coincided with either the maximal size (enhanced optical flow) or the minimal size (reduced optical flow) of the presented flow pattern. Removal of visual information clearly influenced the swinging behavior, in that intersegmental coordination became more stereotyped, reflecting a general stiffening of the swinger. The conditions involving explicit phasing requirements also affected the coordination, but in an opposite way: The coordination became less stereotyped. The two phasing instructions had differential effects: The intersegmental coordination deviated more from normal swinging (i.e., without phasing constraints) when optical flow was enhanced than when it was reduced. Collectively, those findings show that visual information plays a formative role in the coordinative structure of swinging, in that variations of visual information and task constraints were accompanied by subtle yet noticeable changes in intersegmental coordination.     

The role of visual information in control of a constrained locomotor task

The nature of visually guided locomotion was examined in an experiment where subjects had to walk to targets under various conditions. Target distance was manipulated so that subjects had to (a) lengthen their paces in order to hit the target; (b) shorten their paces; (c) make no adjustments to their standard pace length at all. They did this under four visual conditions: (a) normal vision; (b) with vision restricted to a "snapshot" each time the foot that was to be placed on the target was on the ground; (c) with a snapshot each time the foot to be placed was in the swing phase; and (d) no vision after departure fro the target. The results show that the subjects succeed in reaching the target in most cases. However, the smoothness and fluidity of their movements vary significantly between conditions. Under normal vision or where visual snapshots are delivered when the pointing foot is on the ground, locomotion is smoothly regulated as the subjects approach the target. where snapshots are delivered when the pointing foot is in the swing phase, regulation becomes clumsy and ill coordinated. Where no vision is available at all during the approach, adjustments are made, but these are least coordinated of all. The results show that well-coordinated visual regulation does not require continuous visual guidance but depends on intermittent information being available at the appropriate times in the action sequence. Such timing is often more important than the total amount of information that is available for guidance.     

Masked constituent letter priming in an alphabetic decision task

Abstract

The experiments presented here were designed to test whether the prior presentation of a letter in a word, nonword or a string of Xs facilitates the subsequent identification of this letter. Using briefly presented masked primes, clear facilitatory constituent priming effects were obtained in an alphabetic decision task (letter/non-letter classification) when prime letters were flanked by Xs, but the effects disappeared or were greatly reduced when the prime letter formed part of a consonant array (nonword primes). Evidence for word-letter constituent priming was also obtained but almost only for word-initial letten. These facilitatory constituent priming effects were strongest when the target letter was embedded in a string of hash marks and occupied the same relative position in this string as the prime letter in the prime string. The mediating role of letter representations in word recognition and the position-specific coding of character arrays are discussed in the light of these results.     

Leader‐driven distortion of probability and payoff information affects choices between risky prospects

Research indicating that decision makers often distort new information to favor nascent preferences has focused primarily on riskless choice rather than risky choice. In addition, the critical assumption that information distortion mediates the link between the initially preferred alternative and the final choice has not been tested in a compelling manner. In an experiment designed to fill these gaps, participants made six choices involving pairs of hypothetical three‐outcome monetary gambles. We manipulated initial preferences by varying the order in which gamble features were presented. Multilevel regressions indicated that participants distorted their evaluations of precise probabilities and payoffs in the direction of their emerging preferences and that they used their biased evaluations to update those preferences. As expected, information distortion mediated the effect of initial preferences on final choices and final preference strength. In a follow‐up experiment, we compared a standard measure of information distortion (based on comparisons to mean ratings in a no‐choice control task) to a more personalized measure (based on participants' own ratings in the control task) and found the mean‐based measure to be superior for the probability and payoff information in question. Other findings in Experiment 2 corroborated the results of Experiment 1. In both studies, the distortion of quantitative inputs in a simple task highlights the non‐normative circularity of the choice process. Copyright © 2010 John Wiley & Sons, Ltd.     

Reasoning and mathematical skills contribute to normatively superior decision making under risk: evidence from the game of dice task

In this study, we assessed to what extent reasoning improves performance in decision making under risk in a laboratory gambling task (Game of Dice Task-Double, GDT-D). We also investigated to what degree individuals with above average mathematical competence decide better than those with average mathematical competence. Eighty-five participants performed the GDT-D and several numerical tasks. Forty-two individuals were asked to calculate the probabilities and the outcomes associated with the different options of the GDT-D before performing it. The other 43 individuals performed the GDT-D at the beginning of the test session. Both reasoning and mathematical competence had a positive effect on decision making. Different measures of mathematical competence correlated with advantageous performance in decision making. Results suggest that decision making under explicit risk conditions improves when individuals are encouraged to reflect about the contingencies of a decision situation. Interventions based on numerical reasoning may also be useful for patients with difficulties in decision making.     

Spatial probability as an attentional cue in visual search

We investigated the role of spatial probabilities in target location during participants' performance of a visual search task. Experiments 1 and 2 demonstrated that spatial probabilities could serve as a powerful attentional bias that produced faster detection of targets in high-probability locations than of those in low- or random-probability locations. The effect could not be explained by repetition priming alone. Moreover, responses to targets in low-probability locations were slowed only when a distractor was present in the high-probability location. In Experiments 3-5, we compared the effects of spatial probability with an explicit endogenous cue and a salient exogenous cue. Facilitation due to spatial probability was independent of any benefit afforded by the explicit endogenous cue but interacted with the salient exogenous cue, such that the exogenous cue validity effect was compressed for targets in the high-probability location. Together, these results suggest that the spatial probabilities governing target location constitute a potent bias of visual processing and, as such, can be considered an attentional cue that differs from both typical explicit endogenous and salient exogenous cues.     

Developmental differences in the use of visual information during a continuous bimanual coordination task

The authors examined the influence of different amounts of visual information when children 4 (CH4), 6 (CH6), and 8 (CH8) years of age, and adults (n = 12 in each group) performed a steady-state bimanual circle-drawing coordination task at self-selected speeds. All participants maintained in-phase coordination, but different strategies for maintaining the pattern emerged. A predictable relationship between variability and age was not observed, in that the CH8 group was not necessarily more consistent than the CH6 and CH4 groups. The authors conclude that children are transitioning from dependence on kinesthetic feedback to reliance on visual feedback around age 8, as suggested by L. Hay, C. Bard, M. Fleury, and N. Teasdale (1991; L. Hay, M. Fleury, C. Bard, & N. Teasdale, 1994; L. Hay & C. Redon, 1997), and that future studies are needed to further explore visual and kinesthetic feedback as potential control parameters during coordination tasks in developing children.     

Comparison of schizophrenics and normals on a visual search task.

The response times of 16 paranoids, 16 nonparanoids and 16 normals were compared on a search task which required subjects to identify target letters embedded in displays of varying numbers of non-targets. The rate on increase in response times with increased numbers of letters displayed was not markedly different for the various groups, although a derived measure of decision and response-selection time indicated that normals selected responses more rapidly. When compared with normals, schizophrenics seemed to experience more difficulty in response selection and decision than in processing visual stimulus information.     

Interpreting visual preferences in the visual paired-comparison task

Performance on the visual paired-comparison (VPC) task has typically been interpreted with E. Sokolov's (1963) comparator model of the orienting response; novelty preferences are interpreted as evidence of retention, whereas null preferences are interpreted as evidence of forgetting. Here the authors capitalized on the verbal nature of human adults to clarify the interpretation of visual preferences in VPC performance. In 2 experiments, adults were tested on either the VPC task or a forced-choice recognition task after delays of 3 min to 12 months. In Experiment 1, adults tested on the VPC task exhibited novelty preferences after short delays, null preferences after intermediate delays, and familiarity preferences after long delays. In Experiment 2, adults tested on the forced-choice recognition task exhibited high levels of accuracy irrespective of delay, but the latency with which they recognized the stimuli increased systematically over the retention interval. These data are inconsistent with a simple Sokolovian interpretation of VPC performance and instead suggest that memory may be expressed as a novelty preference, null preference, or familiarity preference depending on the accessibility of the representation.