Consistency effects between objects in scenes

How does context influence the perception of objects in scenes? Objects appear in a given setting with surrounding objects. Do objects in scenes exert contextual influences on each other? Do these influences interact with background consistency? In three experiments, we investigated the role of object-to-object context on object and scene perception. Objects (Experiments 1 and 3) and backgrounds (Experiment 2) were reported more accurately when the objects and their settings were consistent than when they were inconsistent, regardless of the number of foreground objects. In Experiment 3, related objects (from the same setting) were reported more accurately than were unrelated objects (from different settings), independently of consistency with the background. Consistent with an interactive model of scene processing, both object-to-object context and object-background context affect object perception.     

Impact and the art of motivation maintenance: The effects of contact with beneficiaries on persistence behavior

We tested the hypothesis that employees are willing to maintain their motivation when their work is relationally designed to provide opportunities for respectful contact with the beneficiaries of their efforts. In Experiment 1, a longitudinal field experiment in a fundraising organization, callers in an intervention group briefly interacted with a beneficiary; callers in two control groups read a letter from the beneficiary and discussed it amongst themselves or had no exposure to him. One month later, the intervention group displayed significantly greater persistence and job performance than the control groups. The intervention group increased significantly in persistence (142% more phone time) and job performance (171% more money raised); the control groups did not. Experiments 2 and 3 used a laboratory editing task to examine mediating mechanisms and boundary conditions. In Experiment 2, respectful contact with beneficiaries increased persistence, mediated by perceived impact. In Experiment 3, mere contact with beneficiaries and task significance interacted to increase persistence, mediated by affective commitment to beneficiaries. Implications for job design and work motivation are discussed.     

Assessment of age-related changes in inhibition and binding using eye movement monitoring

Age-related memory deficits may result from attending to too much information (inhibition deficit) and/or storing too little information (binding deficit). The present study evaluated the inhibition and binding accounts by exploiting a situation in which deficits of inhibition should benefit relational memory binding. Older adults directed more viewing toward abrupt onsets in scenes compared with younger adults under instructions to ignore any such onsets, providing evidence for age-related inhibitory deficits, which were ameliorated with additional practice. Subsequently, objects that served as abrupt onsets underwent changes in their spatial relations. Despite successful inhibition of the onsets, eye movements of younger adults were attracted to manipulated objects. In contrast, the eye movements of older adults, who directed more viewing to the late onsets compared with younger adults, were not attracted toward manipulated regions. Similar differences between younger and older adults in viewing of manipulated regions were observed under free viewing conditions. These findings provide evidence for concurrent inhibition and binding deficits in older adults and demonstrate that age-related declines in inhibitory processing do not lead to enhanced relational memory for extraneous information.     

Arousal at encoding,arousal at retrieval,interviewer support,and children's memory for a mild stressor

The relations among children's physiological arousal at encoding and retrieval, interviewer‐provided social support and children's memory for a mild stressor were examined in 109 five‐ and six‐year‐olds. The children came to a research laboratory and watched a fear eliciting video clip. A week later, their memory for the video clip was tested by either a supportive or nonsupportive interviewer. While watching the video and completing the memory interview, children's heart rate was monitored. Increased heart rate at encoding was associated with fewer incorrect responses. In contrast, increased heart rate at retrieval was associated with poorer memory, but only when the interviewer was nonsupportive. Heart rate was unrelated to memory when the interviewer was supportive. Results suggest that arousal at encoding and retrieval have different implications for children's memory for a mild stressor, particularly in nonsupportive interview contexts. Copyright © 2006 John Wiley & Sons, Ltd.     

Dissemination of psychoactive substance information by innovative drug users.

Internet-based drug information may be relayed by innovative drug users, a group of individuals who use the web to learn about a new drug, experiment with that substance, and then disseminate their knowledge and experiences to others. We investigated the mechanisms adopted by innovative drug-using adolescents to distribute Internet drug information and experiences to peers, the size and geographic distribution of the receiving group, and the age at which innovative drug users began to disseminate drug information. Method: Cross-sectional survey of adolescents recruited by a respondent-driven sampling method. Of 18 innovative drug users, 17 reported using instant messaging (IM) to disseminate drug information and experiences to peers. The average age at which respondents adopted IM for this purpose was 16 years. Fifteen of 17 described using a distribution list with as many as 200 individuals who received only drug information. Ten respondents instant messaged drug information to online peers greater than 250 miles distant; nine respondents attached links to online drug resources (including www.erowid.org). This study has identified that IM plays an important role in the dissemination of Internet-based drug information by individual innovative drug users into larger social networks. Pediatricians should consider assessing IM use in drug abuse evaluations and recommending that parents of children with drug abuse problems should consider suspending IM services as a means of truncating the delivery of reinforcing drug information.     

RESPONSE ALLOCATION IN CONCURRENT CHAINS WHEN TERMINAL‐LINK DELAYS FOLLOW AN ASCENDING AND DESCENDING SERIES

Eight pigeons were trained in a concurrent‐chains procedure in which the terminal‐link immediacy ratio followed an ascending or descending series. Across sessions, one terminal‐link delay changed from 2 s to 32 s to 2 s or from 32 s to 2 s to 32 s, while the other was always 8 s. For all pigeons, response allocation tracked changes in delay and was biased towards the 8‐s alternative on the descending series, indicating a hysteresis effect, and was more sensitive to changes in the terminal‐link delay ratio for relatively long (> 8 s) than short (< 8 s) delays. Both the hysteresis and effect of delay duration were predicted by an extended version of Grace and McLean's (2006) decision model. The extended decision model provided an overall better account of the results than a simple linear‐operator model (Grace, 2002), and holds promise for an integrated account of choice in concurrent chains for both acquisition and steady‐state conditions.     

Does valence matter? Effects of negativity on children’s early understanding of the truth and lies

Early deceptive behavior often involves acts of wrongdoings on the part of children. As a result, it has often been assumed, although not tested directly, that children are better at identifying lies about wrongdoing than lies about other activities. We tested this assumption in two studies. In Study 1, 67 3- to 5-year-olds viewed vignettes in which a character truthfully or falsely claimed to have committed a good or bad act. Children were biased to label claims that the character had committed a good act as the truth and claims that the character had committed a bad act as lies. In Study 2, 51 4- to 6-year-olds viewed vignettes in which characters either admitted or denied committing a good or bad act. Children were better at identifying truth-tellers and liars when the acts were good. Results suggest that young children initially overgeneralize the concept of lie to include all negative acts and the concept of the truth to include all good acts and only gradually make a distinction between act valence and honesty. As a result, including wrongdoing in scenarios to test children's early understanding of the meaning of lying is likely to underestimate children's abilities.     

Resistance to change and preference for variable versus fixed response sequences

In Experiment 1, 4 pigeons were trained on a multiple chain schedule in which the initial link was a variable-interval (VI) 20-s schedule signalled by a red or green center key, and terminal links required four responses made to the left (L) and/or right (R) keys. In the REPEAT component, signalled by red keylights, only LRLR terminal-link response sequences were reinforced, while in the VARY component, signalled by green keylights, terminal-link response sequences were reinforced if they satisfied a variability criterion. The reinforcer rate for both components was equated by adjusting the reinforcer probability for correct REPEAT sequences across sessions. Results showed that initial- and terminal-link responding in the VARY component was generally more resistant to prefeeding, extinction, and response-independent food than responding in the REPEAT component. In Experiment 2, the REPEAT and VARY contingencies were arranged as terminal links of a concurrent chain and the relative reinforcer rate was manipulated across conditions. For all pigeons, initial-link response allocation was biased toward the alternative associated with the VARY terminal link. These results replicate previous reports that operant variation is more resistant to change than operant repetition (Doughty & Lattal, 2001), and show that variation is preferred to repetition with reinforcer-related variables controlled. Behavioral momentum theory (Nevin & Grace, 2000) predicts the covariation of preference and resistance to change in Experiments 1 and 2, but does not explain why these aspects of behavior should depend on contingencies that require repetition or variation.