Knowledge that Transforms

Stereopsis is the perception of depth generated from differences between the two eyes' views of a single image; this difference is termed disparity. When artists learn to draw, they are often instructed to close one eye; this defeats stereopsis and makes monocular depth cues—such as perspective, occlusion, and shading—more apparent. In this study, we tested the hypothesis that poor stereopsis might therefore be an asset to someone whose goal is to represent the three-dimensional world on two-dimensional surfaces (Livingstone & Conway, 2004).

Sensory information must be processed selectively in order to represent the world and guide behavior. How does such selection occur? Here we consider two alternative classes of selection mechanisms: In blocking, unattended stimuli are blocked entirely from access to downstream processes, and in attenuation, unattended stimuli are reduced in strength but if strong enough can still access downstream processes. Existing evidence as to whether blocking or attenuation is a more accurate model of human performance is mixed. Capitalizing on a general distinction between blocking and attenuation-blocking cannot be overcome by strong stimuli, whereas attenuation can-we measured how attention interacted with the strength of stimuli in two spatial selection paradigms, spatial filtering and spatial monitoring. The evidence was consistent with blocking for the filtering paradigm and with attenuation for the monitoring paradigm. This approach provides a general measure of the fate of unattended stimuli.

Psychological Science http://pss.sagepub.com/ Ego Threat and Intergroup Bias : A Test of Motivated-Activation Versus Self-Regulatory Accounts Thomas J. Allen and Jeffrey W. Sherman Psychological Science 2011 22: 331 originally published online 11 February 2011 DOI: 10.1177/0956797611399291 The online version of this article can be found at: http://pss.sagepub.com/content/22/3/331 Published by: http://www.sagepublications.com On behalf of: Association for Psychological Science Additional services and information for Psychological Science can be found at: Email Alerts: http://pss.sagepub.com/cgi/alerts Subscriptions: http://pss.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav Downloaded from pss.sagepub.com at UNIV CALIFORNIA DAVIS on August 9, 2011

Salience and satisfaction are important factors in determining the comparisons that people make. We hypothesized that people make salient comparisons first, and then make satisfying comparisons only if salient comparisons leave them unsatisfied. This hypothesis suggests an asymmetry between winning and losing. For winners, comparison with a salient alternative (i.e., losing) brings satisfaction. Therefore, winners should be sensitive only to the relative value of their outcomes. For losers, comparison with a salient alternative (i.e., winning) brings little satisfaction. Therefore, losers should be drawn to compare outcomes with additional standards, which should make them sensitive to both relative and absolute values of their outcomes. In Experiment 1, participants won one of two cash prizes on a scratch-off ticket. Winners were sensitive to the relative value of their prizes, whereas losers were sensitive to both the relative and the absolute values of their prizes. In Experiment 2, losers were sensitive to the absolute value of their prize only when they had sufficient cognitive resources to engage in effortful comparison.

Even in the presence of irrelevant stimuli, word production is a highly accurate and fluent process. But how do speakers prevent themselves from naming the wrong things? One possibility is that an attentional system inhibits task-irrelevant representations. Alternatively, a verbal self-monitoring system might check speech for accuracy and remove errors stemming from irrelevant information. Because self-monitoring is sensitive to social appropriateness, taboo errors should be intercepted more than neutral errors are. To prevent embarrassment, speakers might also speak more slowly when confronted with taboo distractors. Our results from two experiments are consistent with the self-monitoring account: Examining picture-naming speed (Experiment 1) and accuracy (Experiment 2), we found fewer naming errors but longer picture-naming latencies for pictures presented with taboo distractors than for pictures presented with neutral distractors. These results suggest that when intrusions of irrelevant words are highly undesirable, speakers do not simply inhibit these words: Rather, the language-production system adjusts itself to the context and filters out the undesirable words.

Probability matching is the tendency to match choice probabilities to outcome probabilities in a binary prediction task. This tendency is a long-standing puzzle in the study of decision making under risk and uncertainty, because always predicting the more probable outcome across a series of trials (maximizing) would yield greater predictive accuracy and payoffs. In three experiments, we tied the predominance of probability matching over maximizing to a generally adaptive cognitive operation that generates expectations regarding the aggregate outcomes of an upcoming sequence of events. Under conditions designed to diminish the generation or perceived applicability of such expectations, we found that the frequency of probability-matching behavior dropped substantially and maximizing became the norm.

Visual pattern processing becomes increasingly complex along the ventral pathway, from the low-level coding of local orientation in the primary visual cortex to the high-level coding of face identity in temporal visual areas. Previous research using pattern aftereffects as a psychophysical tool to measure activation of adaptive feature coding has suggested that awareness is relatively unimportant for the coding of orientation, but awareness is crucial for the coding of face identity. We investigated where along the ventral visual pathway awareness becomes crucial for pattern coding. Monoptic masking, which interferes with neural spiking activity in low-level processing while preserving awareness of the adaptor, eliminated open-curvature aftereffects but preserved closed-curvature aftereffects. In contrast, dichoptic masking, which spares spiking activity in low-level processing while wiping out awareness, preserved open-curvature aftereffects but eliminated closed-curvature aftereffects. This double dissociation suggests that adaptive coding of open and closed curvatures straddles the divide between weakly and strongly awareness-dependent pattern coding.

The visual system groups elements within the visual field that are physically separated yet similar to each other. Although grouping processes have been intensely studied for a century, the mechanisms of grouping remain elusive. We propose that a primary mechanism for grouping by common fate is attentional selection of a direction of motion. A unique prediction follows from this account: that the visual system must be limited to forming only a single common-fate group at a time, and that attempts to find a particular common-fate group among other groups, or among nongroups, should therefore be highly inefficient. We show that this is true in searches for vertically oriented groups of moving dots among horizontally oriented groups (Experiment 1) and in searches for motion-linked groups among nonlinked objects (Experiment 2). Feature selection may limit the visual system to the construction of only one common-fate group at a time, and thus the experience of simultaneous grouping may be an illusion.

A major debate in the study of word learning centers on the extension of categories to new items. The rational approach assumes that learners make structured inferences about category membership, whereas the mechanistic approach emphasizes the attentional and memory processes that form the basis of generalization behaviors. Recent support for the rational view comes from observations of the suspicious-coincidence effect: People generalize category membership narrowly when presented with three subordinate-level exemplars that share the same label and generalize category membership broadly when presented with one exemplar. Across three experiments, we examined the mechanistic basis of this effect. Results showed that the presentation of multiple subordinate-level exemplars led to narrow generalization only when the exemplars were presented simultaneously, even when the number of exemplars was increased from three to six. These data demonstrate that the suspicious-coincidence effect is firmly grounded in the general cognitive processes of attention, memory, and visual comparison.

Visceral states are known to reduce the ability to exert self-control. In the current research, we investigated how self-control is affected by a visceral factor associated with inhibition rather than with approach: bladder control. We designed four studies to test the hypothesis that inhibitory signals are not domain-specific but can spill over to unrelated domains, resulting in increased impulse control in the behavioral domain. In Study 1, participants' urination urgency correlated with performance on color-naming but not word-meaning trials of a Stroop task. In Studies 2 and 3, we found that higher levels of bladder pressure resulted in an increased ability to resist impulsive choices in monetary decision making. We found that inhibitory spillover effects are moderated by sensitivity of the Behavioral Inhibition System (Study 3) and can be induced by exogenous cues (Study 4). Implications for inhibition and impulse-control theories are discussed.