A general mechanism for decision-making in the human brain?

A new fMRI study by Heekeren and colleagues suggests that left dorsolateral prefrontal cortex (DLPFC) contains a region that integrates sensory evidence supporting perceptual decisions. DLPFC meets two criteria posited by Heekeren et al. for such a region: (1) its activity is correlated in time with the output of sensory areas of the visual cortex measured simultaneously, and (2) as expected of an integrator, its activity is greater on trials for which the sensory evidence is substantial than on trials for which the sensory evidence is weak. Complementary experiments in humans and monkeys now offer a realistic hope of elucidating decision-making networks in the primate brain.     

Visual marking and the perception of salience in visual search

In the present study, the gap paradigm originally developed by Watson and Humphreys (1997) was used to investigate whether the process of visual marking can influence the perceptual salience of a target in visual search. Consistent with previous studies (Watson & Humphreys, 1997), the results showed that search was not affected by the presence of the preceding distractors when the target was relatively low in salience. This finding suggests that visual marking can increase the efficiency of visual search by decreasing the size of the search set. However, more important, the results also showed that search was affected by the presence of the preceding distractors when the target was relatively high in salience. This finding suggests that visual marking may be limited in its ability to increase the perceptual salience of the target. Together, the results of the present study suggest that the effectiveness of visual marking may vary as a function of search context.     

Inhibition of return at multiple locations in visual search: When you see it and when you don't

Using a novel sequential task, Danziger, Kingstone, and Snyder (1998) provided conclusive evidence that inhibition of return (IOR) can co-occur at multiple non-contiguous locations. They argued that their findings depended crucially on the allocation of attention to cued locations. Specifically, they hypothesized that because subjects could not predict whether an onset event was a target or a non-target, all onset events had to be attended. As a result, non-targets were tagged with inhibition. The present study tested this hypothesis by manipulating whether target onset was predictable or not. In support of Danziger et al., three experiments revealed that multiple IOR was only observed when attention had to be directed to the cued locations. Interestingly, when attention did not need to be allocated to the cued locations, and multiple IOR was abolished, an IOR effect was still observed at the most recently cued location. Two possible accounts for this single IOR effect were presented for future investigation. One account attributes the effect to motor-based inhibition as hypothesized by Klein and Taylor (1994). The alternative account attributes the effect to weak attentional capture by a peripheral cue. Together the data support the view that multiple IOR is an attentional phenomenon and, as hypothesized by Tipper, Weaver, and Watson (1996), its presence or absence is largely under the control of the observer.     

Alcohol Affects Emotion Through Cognition

Determining how cognition and emotion interact is pivotal to an understanding of human behavior and its disorders. Available data suggest that changes in emotional reactivity and behavior associated with drinking are intertwined with alcohol's effects on cognitive processing. In the study reported here, we demonstrated that alcohol dampens anticipatory fear and response inhibition in human participants not by directly suppressing subcortical emotion centers, as posited by traditional tension-reduction theories, but instead by impairing cognitive-processing capacity. During intoxication, reductions in fear response (assessed via startle potentiation) occurred only under dual-stimulus conditions, and coincided with reduced attentional processing of threat cues as evidenced by brain response (assessed via P3 event-related potentials). The results are consistent with higher cortical mediation of alcohol's effects on fear, and illustrate more broadly how disruption of a cognitive process can lead to alterations in emotional reactivity and adaptive behavior.     

Interpersonal leveling,independence, and self‐enhancement: a comparison between Denmark and the US,and a relational practice framework for cultural psychology

We argue that the relational model that people use for organizing specific social interactions in any culture determines whether people self‐enhance. Self‐enhancement is not a functional consequence of the (independent or interdependent) cultural model of self. Across three studies, Danes self‐enhanced considerably less than did Americans but were more independent on the Twenty Statements Test, made more individual attributions about social life, made more autonomous scenario choices, and were more independent on the self‐construal scale. Public modesty did not account for these Danish‐American differences in self‐enhancement. However, Danes practiced interpersonal leveling, preferring equality of outcome more than did Americans. This leveling strongly and inversely predicted self‐enhancement within both cultures and mediated Danish‐American differences in self‐enhancement. In contrast, no independence measure systematically predicted self‐enhancement within both cultures nor mediated the cultural differences in self‐enhancement. This dissociation of independence and self‐enhancement demonstrates that self‐enhancing downward social comparisons are not functionally necessary for an independent concept of self. We conclude that social relationships, not the model of the self, mediate the mutual constitution of psyche and culture. Copyright © 2006 John Wiley & Sons, Ltd.     

Feature and conjunction effects in recognition memory: Toward specifying familiarity for compound words

In three experiments, we evaluated potential sources of familiarity in the production of feature and conjunction errors with both word (Experiments 1 and 3) and nonword (Experiment 2) stimuli and related this work to various dual-process models of memory. The contributions of letter, syllable, lexical morpheme, and conceptual information were considered. Lexical morpheme information was consistently more potent than syllable information in leading to feature and conjunction errors across Experiments 1 and 2, and a word length explanation did not account for this consistent finding. In addition, there was no impact of conceptual information on these errors (Experiments 1-3). The results support a familiarity-based interpretation of feature and conjunction errors and a lexical morpheme basis for the familiarity in compound words. In order to be more comprehensive, memory models may need to account for a lexical morpheme source of familiarity.     

Predictability influences stopping and response control

Using a continuous tracking task, the authors examined whether stopping is resistant to expectancies as well as whether it is a representative measure of response control. Participants controlled the speed of a moving marker by continuously adjusting their response force. Participants stopped their ongoing tracking in response to auditory signals on 25%, 50%, 75%, or 100% of trials. Stopping was contrasted with accelerating, in which participants accelerated the marker in response to the signals. In Experiment 1, on each trial participants either stopped or accelerated, allowing a trade-off between the two. In Experiments 2 and 3, participants only stopped or only accelerated, thus decreasing the likelihood of a trade-off. When a trade-off was possible, stopping was resistant to expectancies. However, with little or no trade-off, expectancies influenced stopping and accelerating similarly. These findings contrast with the established view that stopping is insensitive to expectancies. In addition, when trade-offs are prevented, these results confirm that stopping is representative of other response adjustment measures.     

Getting over "the problem of other minds": communication in context

Theories of communication often assume that communication has a single, essential form or telos, the culmination of a one-track developmental process where precursors eventually give rise to the real thing. At one time, this essence of communication was identified with linguistic competence, whereas now it is largely defined in terms of "Theory of Mind." But the fundamental problem with "Theory of Mind" is the very problem it pretends to solve: "the problem of other minds."That problem, as formulated, is insoluble, even with the aid of theory or innate modules. In this article, we reject the superficial depth psychology of "Theory of Mind" in favour of a breadth psychology based on context.     

Alive communication

The purpose of this paper is to propose a theoretical model, based on a dynamic systems perspective and the metaphor of aliveness in communication. Traditional concepts and methods for the study of communication are relatively static and based on the metaphor of signal and response. These traditional methods lend themselves to relatively simplified measures of frequencies and durations, sequences and co-occurrences: a model of objectified communication. The concept of alive communication focuses on the dynamically changing aspects of communication using three related components: coregulation, ordinary variability, and innovation. Like living organisms, alive communication develops over time as it forms dynamically stable patterns. Aliveness can be applied to communication at any age, in any species, between species, in any form including time-delayed practices using written symbols, and with non-living objects. The model provides a tool for evaluating the "life-likeness" of communication with animate and inanimate objects and robotic devices, and for assessing and treating communicative difficulties--in which aliveness is missing--within and between dyads/families.