Chunking versus foraging search patterns by rats in the hierarchically baited radial maze

Rats were exposed to a radial maze containing six black smooth arms and six wire-grid-covered arms and a striped 'exit arm' in experiment 1. The probability of a black or grid arm being baited (5/6 vs 1/6) with sunflower seeds was associated with its proximal cue for some rats (the Relevant Arm Cue group) but not for others (the Irrelevant Arm Cue group). All rats could terminate a trial and receive a highly preferred morsel of apple by entering the exit arm only after having sampled all six seed-baited arms. Relevant Arm Cue rats usually chose some arms from the more densely baited set before choosing an arm from the less densely baited set and made fewer reentries than Irrelevant Arm Cue rats. Although such clustered, higher choice accuracy in the Relevant Arm Cue group corresponds to human clustered, better recall of verbal items from lists hierarchically organized by categories, these rats did not similarly exhaustively retrieve items (arm locations). That is, when required to terminate a trial by entering the 'exit' arm for an apple morsel after having sampled all seed-baited arms, both groups were equally unable to withhold making nonrewarded premature exits. This nonexhaustive foraging search pattern was maintained in the next two experiments in which the radial maze was reduced to three black and three grid arms along with the striped 'exit' arm and in which black and grid arm cues were paired with number of seeds (eight or one) in an arm for Relevant Arm Cue rats. Although Relevant Arm Cue rats displayed perfect clustering by entering all eight-seeded arms before a one-seeded arm, they made more premature exits and reentries into eight-seeded arms in experiment 2 or when forced to enter all eight-seeded arms in experiment 3 than did Irrelevant Arm Cue rats. These foraging tendencies prevent accurate estimations of the amount of information (i.e., arm locations) rats can 'chunk'. Electronic Publication     

The impact of character attribution on composite production: A real world effect?

Facial memory draws upon both veridical detail and beliefs based upon prior knowledge and stereotypes. Shepherd, Ellis, McMurran, and Davies (1978) demonstrated that subjects' perception and subsequent reconstruction of a face using the “Photofit” kit was significantly influenced by whether they believed the person to be a multiple murderer or a local hero. The current study explored whether similar effects would occur when the face involved was one of four male celebrities about which subjects held pronounced positive or negative views and where reconstruction was accomplished using the computerised “E-fit” composite system. Semantic differential ratings showed significant influences of liking on subjects' perception and reconstruction of the faces involved, though the pattern of effects was not always readily predictable. Liking also influenced accuracy of reconstruction; ranking and naming data showed that the best composites were made by subjects who disliked the target and made their reconstructions with the aid of a photograph.     

The impact of character attribution on composite production: A real world effect?

Facial memory draws upon both veridical detail and beliefs based upon prior knowledge and stereotypes. Shepherd, Ellis, McMurran, and Davies (1978) demonstrated that subjects' perception and subsequent reconstruction of a face using the “Photofit” kit was significantly influenced by whether they believed the person to be a multiple murderer or a local hero. The current study explored whether similar effects would occur when the face involved was one of four male celebrities about which subjects held pronounced positive or negative views and where reconstruction was accomplished using the computerised “E-fit” composite system. Semantic differential ratings showed significant influences of liking on subjects' perception and reconstruction of the faces involved, though the pattern of effects was not always readily predictable. Liking also influenced accuracy of reconstruction; ranking and naming data showed that the best composites were made by subjects who disliked the target and made their reconstructions with the aid of a photograph.     

Exposure to Media Images of Female Attractiveness and Concern with Body Weight Among Young Women1

Despite the popular belief that the thinstandard of female attractiveness currently presented inthe media is a primary contributor to the high level ofconcern with body weight among women, experimental studies have not shown that exposure to mediaimages increases women's weight concern. Threeexperiments are reported demonstrating that exposure tomedia images does often result in increased weightconcern among women, but that body dissatisfaction, astable personality characteristic, is a moderator ofvulnerability to this effect. Although most womenreported higher weight concern when exposed to media vs. neutral images, women with low initial bodydissatisfaction did not. In addition, this researchsuggests that negative effects on weight concern mayresult from even passive exposure to media images, but that exposure to realistic attractivenessis less likely to cause increased weight concern. Theethnicity of the participants in these studies reflectedthat of the local population, with over 90% white. The nonwhite participants primarily belonged toone of the following groups; Asian, Pacific Islander,Latino.     

Effects of High-Probability Request Sequences on Preschoolers' Compliance and Disruptive Behavior

A high-probability request sequence was implemented with three preschool children with developmental delays within their classroom during typical activities. A multiple baseline design across subjects was used to evaluate the effects of the high-probability request sequence on compliant responding to low-probability requests and the occurrence of disruptive behavior. Results of the study indicate that the use of the high-probability request sequence was effective in increasing compliant responding to low-probability requests delivered by two different trainers for all children. No increases in disruptive behavior were noted as a result of using the high-probability request sequence. When the high-probability request sequence was withdrawn, compliant responding to low-probability requests was maintained for all children across time and in different settings.     

Negative Affectivity, Social Support, and the Prediction of Depression and Distress

ABSTRACT In the work we present in this article, we examined the contaminating effects of trait negative affectivity (TNA) on the relations between social support and psychological distress among college undergraduates. In the first study, it was suspected that controlling for TNA would substantially alter the associations between social support (as measured by the Social Provisions Scale) and depression at the initial assessment and later with negative mood prior to a course examination. Actual results from cross-sectional hierarchical regression analyses revealed that controlling for TNA reduced-but did not nullify-associations between reassurance of worth support and depression. TNA did not mediate the relation of reliable alliance support to state NA measured 2 weeks later prior to a course examination. Finally, a second study controlling for TNA found reassurance of worth support remained a significant prospective predictor of depression during the week of final examinations. Results are integrated with theoretical and measurement issues in social support research.     

Positive crossover: Parent perceived partner responsiveness and health of youth with asthma

Romantic relationship functioning has implications that extend beyond the romantic dyad. This study tests whether a key positive aspect of relationships, perceived partner responsiveness, can cross over from parents' romantic relationships to children's health and well-being via parenting behavior. In a sample of 112 youth with asthma and their primary caregivers, when caregivers perceived higher partner responsiveness in their romantic relationship, youth experienced improved self-reported asthma symptoms, pulmonary functioning, and positive affect. The associations were robust while controlling for parents' relationship conflict and other relevant covariates, except for the pulmonary functioning outcome, which was instead predicted by parents' conflict. However, parenting behavior (i.e., positive and negative parenting) did not appear to mediate these links. This work highlights the importance of positive romantic relationship processes for youth health and well-being, emphasizing the relevance of clinical intervention work and the need to continue investigating mechanisms through which these processes may be linked.     

Cognitive Behavioral Treatment of PTSD with Comorbid Panic Attacks

Many individuals that experience traumatic events such as sexual and physical assault develop posttraumatic stress disorder (PTSD). More recently, research has indicated that a significant proportion of PTSD sufferers may also have comorbid panic attacks. Although there are several effective treatments that focus on alleviating PTSD symptoms, until now there were no treatments that focused on also treating comorbid panic attacks. Multiple channel exposure therapy (M-CET) is the first treatment developed to specifically treat comorbid PTSD and panic attacks. It is also unique in that it has been used to treat women who have multiple trauma histories as well as a wide range of different types of traumatic event exposure in a group format. This treatment is described in a session by session format and special considerations in implementing the treatment are discussed.